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Foundation Systems for High-Rise Structures

Rolf Katzenbach, Steffen Leppla, Deepankar Choudhury

Spread foundations

Publication details https://www.routledgehandbooks.com/doi/10.1201/9781315368870-4 Rolf Katzenbach, Steffen Leppla, Deepankar Choudhury Published online on: 15 Aug 2016

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– SINGLE AND STRIP FOUNDATIONS STRIP AND SINGLE Cyclic freezing and unfreezing and Cyclic freezing Maceration water by drifty density bulk of the Reduction Leaching 3 ]. 3 Figure 3.1 27 - -

Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 28 dents have to be analyzed [ have analyzed dents to be in explained is of spread foundations issue This considered. is subsoil of the behavior material arigid-plastic (ULS), state limit ultimate of the design the for contrast, In considered. is subsoil of behavior the material elastic linear a (SLS), state limit stability of the analysis For the ULS. the and SLS the of analysis geotechnical for the used are models Two theoretical different 3.3.1 3.3 phase. construction the during supervised and precisely planned to be has joints settlement and joints expansion joints, oftion construction installa the case, any In limited. to be has concrete of the width crack the conditions, Toor weather to repel ments. influx prevent groundwater avoid reinforce can shear haunches concrete or arranging slab thickness the (concentrated loads). punching Increasing on the as well as moment, [ water influx layers) (e.g., bitumen system to prevent ground sealing additional an with combination or in trough, white of aso-called apart as used be can tions founda Raft have homogenized. to be construction the and subsoil of the deformations the and dense is load grid the when used are foundations Raft 3.2 Figure 3.1

According to the technical standards and regulations, the following inci following the regulations, and standards technical to the According bending on the slab depends reinforcedconcrete of the thickness The Figure 3.2 • •

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation RAFT FOUNDATIONS RAFT GEOTECHNICAL ANALYSIS Sliding Overall stability

Basics

Single and strip foundation. strip and Single . 4 – 7 ]. 8 – 11 ]: - - - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 available[ are procedures calculation following The of spread foundations. analysis the for basis the is pressure contact of the distribution of the knowledge The 3.3.2 [ settlements harmful and failure against of safety analysis the account into take tablevalues standard The table values. of standard basis done on the be can spread foundations [ considered to be has mechanisms) complex rupture circles, (slip mechanism failure possible Every necessary. is slope failure ofsis the Figure 3.2 In simple cases and under certain conditions, the geotechnical analysis of analysis geotechnical the conditions, certain under and cases simple In analy an of embankments, area the in located are spread foundations If • • • • • • •

d. b. a. Unacceptable vibrations Unacceptable of frost aresult as uplift Large settlements Large movement of foundation aresult as failure Structural compressing Punching, structure and of soil failure Collective failure Base c. e.

Distribution of the contact pressure contact the of Distribution

Load-settlement curve for spread foundations. spread for curve Load-settlement Numerical methods, for example, finite element method element finite for example, methods, Numerical method modulus Stiffness method modulus reaction Subgrade method trapeze Stress [ to Boussinesq according foundations rigid under pressure contact of the Distribution 15 Se ttlement , 16 ]. Se rv be linear el as A s iceability limitstate(S ppr sume ha 10 vior ox ]. d scop imatel as tic material y e with 17 ] LS ) (U ultimate limitstat to theth Limit loadaccordin LS ) Load eo ry Spread foundations Spread P ofth e e g 12 – 14 ].

29 - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 only in simple cases. simple in only applicable is method This foundation. the under subsoil the in processes of transfer because arise cannot which foundation, of the edge at the tensions large infinitely (a) theoretically to offers Boussinesq according 30 increasing load, the constant settlements under the foundation increase increase foundation the under settlements constant the load, increasing an load. With on the depending moment, of the curve the and pressure, side. unsafe on the results to leads pressure contact of the distribution of aconstant assumption the SLS, of the For analysis ULS. of the side for analysis safe on the to results place. not take will pressure contact of the A redistribution capacity, punching. for example, load-bearing internal of the excess in failure. to abase leads which foundation the of center to the pressure contact (c) the of the load to aredistribution leads case In hinge. plastic of the capacity rotation on the depends foundation of the capacity bearing the case this In pressure. contact of the tribution aredis causes which foundation the inside hinge load to aplastic leads (b) the case In may occur. mechanisms failure different two capacity ing poorly. exploited is load approaches the capacity bear to the When bearing Figure 3.3 [ soil sub of the stability load the and relation between the as well as foundation considered. be can subsoil of behavior the material nonlinear the well as structure of the stiffness the because analysis by numerical given is pressure contact of the distribution realistic The most analysis. the for sufficient usually are methods These below aspread foundation. pressure contact of the distribution the mine pressure. contact of the distribution realistic most to the leads method modulus stiffness The trough. settlement load to a leads Auniform springs. of connected asystem with half-space elastic an as considered is subsoil the method, modulus stiffness the Using trough. no settlement with settlement load to auniform leads A uniform springs. of independent asystem as considered is subsoil the lus method, modu reaction subgrade the Using foundations. raft and strip, single, for used be big.can It is depth foundation (d) the if method suitable, are depths. foundation small and foundations approach small using when auseful is method trapeze stress of the aconsequence as pressure contact of the distribution The assumed. of stresses distribution alinear only is

The distribution of the contact pressure under rigid foundations foundations rigid under pressure contact of the distribution The Figure 3.4 leads pressure contact of the distribution of aconstant assumption The follows failing a brittle ductility, no sufficient has foundation the If of the stiffness on the depends pressure contact of the distribution The (a) methods to (d) calculation approximatesolutions to deter The are modulus (c) method stiffness modulus the and reaction subgrade The (b), there method because trapeze stress the is procedure simplest The Foundation Systems for High-Rise Structures High-Rise for Systems Foundation 18 ]. The potential distributions of the contact pressure are shown in in shown are pressure contact of the distributions potential ]. The . Case (a) shows the distribution of the contact pressure when the the when pressure (a) contact of the . Case distribution shows the shows the settlement trough, the distribution of the contact contact of the distribution the trough, settlement shows the - - - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 of the subsoil, needs to be analyzed. to be needs subsoil, of the stiffness to the stiffness structure of the proportion on the depends which pressure, contact the force variable, internal of the determination For the 3.3.2.1 load. the under concentrated are moments bending The foundation. of the center to the shifted is border area, the in centrated con is which pressure, contact the time, same center. the the At in strongly Figure 3.3

System rigidity System Heidelberg, Germany, 1471–1490, Germany, 2012.) Heidelberg, Bauingenieure:Technik,für und Organisation Wirtschaftlichkeit al., et Katzenbach, (From failure. Base (c) foundation; the in hinge (b) Plastic soil; the and foundation the of behavior (a) Elastic foundations. single under pressure contact the of Distribution (b (a) (c) ) Baugrund-Tragwerk-Interaktion. Handbuch Handbuch Baugrund-Tragwerk-Interaktion. Spread foundations Spread . Springer-Verlag,

31 - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 32 Figure 3.4

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation

Heidelberg, Germany, 1471–1490, Germany, 2012.) Heidelberg, Technik, Bauingenieure: für und Organisation Wirtschaftlichkeit al., et Katzenbach, (From moment. (c) bending pressure; (b) contact (a) Deformation; loading. its of dependency in foundation asingle of stresses and deformations of progression Qualitative (b (a) (c) M ) σ S 0.25 P 0.75 P 0.25 P 1.0 P Baugrund-Tragwerk-Interaktion. Handbuch 0.25 P 1.0 P 0.75 P 1.0 P 0.5 P 0.5 P 0.5 P 0.75 P . Springer-Verlag, Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 E material building of the of modulus elasticity the and l, length the h, component height by the determined is It to Equation 3.2. according in stated is ferentiation dif The (Equation 3.1). foundation the and structure the between actions inter of the to avalueassessment Kany, is for the which Kaccording rigidity system the by defined is foundations rigid and limp between differentiation arises stresses edge high with pressure contact bution of the distri anonlinear foundations For rigid load to distribution. the respondents Figure 3.5 ( half-space isotropic elastic the in founded where: For limp spread foundations, the distribution of the contact pressure cor pressure contact of the distribution the spread foundations, For limp

K K E E I h b B B l (a) s = =

Distribution of the contact pressure for limp (a) and rigid (b) spread foundations. (b) spread (a) rigid and limp for pressure contact the of Distribution structur Eb ======subsoi EI s K 0.001 K Table 3.1 modulus of elasticity of the structure [kN/m structure of the of modulus elasticity height of the spread foundation [m] spread foundation of the height [kN/m subsoil of modulus the oedometric [m spread foundation of the moment of inertia geometrical length of the spread foundation [m] spread foundation of the length [m] spread foundation of the width BB ⋅ ⋅ < ≥ ⋅ 0.001 0.1 l 3 ls ≤ es = K tiffn

E (K <0.001) tiffn Eb Differentiation between limp and rigid foundations rigid and limp between Differentiation < B s 0.1 ⋅ ⋅ Table 3.1 es bh es 12 s ⋅ ⋅ s l 3 3

= 12 1 [ 16 ⋅⋅ Limp foundation Intermediate area Rigid foundation E E , B 21 s    ]. The system rigidity K is determined determined Kis rigidity system ]. The (b h l )    Figure 3.6 3

(K ) [ Spread foundations Spread ≥ 2 16 0.1) ] 2 – ] 20 ( Figure 3.5 ]: B , which is is , which ). The ). The (3.2) (3.1)

4 ] 33 - - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 behavior with big edge stresses stresses big edge with behavior nonlinear astrong has pressure contact of the distribution The forms. their center. the from outward at radius is 0.845 of the point teristic charac the spread foundations, center. the For from circular outward width at is 0.74 foundations half- of the for rectangular point characteristic The spread foundation of arigid settlement the as same the is point cases. special in only considered is construction rising of the rigidity The building. of the rigidity to the consider componentused is foundation the 34 Figure 3.7 with accordance Kin rigidity have asystem Figure 3.6

Regardless of the load position and size, rigid spread foundations keep keep spread foundations rigid size, load and of position the Regardless (K spread foundations For limp of rigidity the only normally of spread foundations, calculation For the Circular spread foundations with a component height h and a diameter d a diameter hand a component height with spread foundations Circular Foundation Systems for High-Rise Structures High-Rise for Systems Foundation K foundatio of alimpspread Se =⋅

ttlement 12 Characteristic point of a rectangular spread foundation. spread arectangular of point Characteristic Dimensions for determining the rigidity of the system. the of rigidity the determining for Dimensions 1 E E n B S cu ⋅ h    rv d h e    3

2 b ( Figure 3.5 < 0.001), the settlement at the characteristic 0.001), characteristic at the settlement the b 0.74 ). . 2 b σ l 0 = foundatio of ari Se po Charac ttlement cons in t gi ta te d spread nt ristic n ( cu Figure 3.7 rv e (3.3) ). - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 that are “on the safe side” become necessary. side” “on are safe become that the assumptions conservative or sufficient studies more detailed Otherwise, [ method trapeze stress the or with to Boussinesq, according mined deter be can pressure contact of the distribution the abig thickness, with [ equations following the enhanced Borowicka e, eccentricity an with by Equation 3.4 given bis awidth with [ cases simple in spread foundations for rigid used be can that developed equations 1885, year the in Boussinesq half-space, isotropic elastic an as modeled is subsoil the that assumption on the Based 3.3.2.2 Figure 3.8

For rigid spread foundations, single foundations, and strip foundations foundations strip and foundations, single spread foundations, For rigid The distribution of the contact pressure under a rigid strip foundation foundation strip arigid under pressure contact of the distribution The σ e e 0 ≤= >=

=

b b 4 4 rigid foundations according to Boussinesq according foundations rigid under pressure contact the of Distribution Boussinesq. to according foundations rigid under pressure contact the of Distribution 2V : , π σ σ ⋅ ⋅ b 0 0 ⋅ 2V 2V π π 1 ⋅ ⋅ ⋅ ⋅ 1 − b b ξ ⋅ ⋅ 2 14 σ 1 0 1 +⋅ ∞∞ + wher − () 1 ξ ξ − 1 1 2 e ξ 2 b e b 2 ⋅ ξ wher ξ

= V z 2x e b ⋅ ( 2 b ξ Figure 3.8

1 = 2x 2b +− 17 − b4 ). For an eccentric load ). eccentric For an ]. 4e Spread foundations Spread e

x 22 (3.5) (3.6) (3.4)

16 ]: 35 ]. - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 determine the distribution of the contact pressure of an arbitrarily spread arbitrarily of an pressure contact of the distribution the determine To directions. in opposite value point but same the and of influence line have same the pressures contact the and forces of the resultant The force. plane. remain cross-sections the that stating of Bernoulli assumption on the based are considerations All possible. notis immediately due to plasticization peaks of stress reduction of the detection The possible. theoretically are stresses edge Even large for calculation. behaviour elastic linear with simplified is respectively. Subsoil interactions, subsoil or the 36 conditions conditions principles. of elastostatic theory beam on the based is method trapeze stress The pressure. contact of the distribution the to determine the oldest and is it method, defined astatically is method trapeze stress The 3.3.2.3 [ foundations of the center to the shift stresses the and foundations of the edges at the plasticizes subsoil The occur. cannot stresses peak these subsoil, of the strength shear by the capacity, imposed bearing ultimate the using determined be can pressure contact the Figure 3.9

The force V is the resultant of the applied load, self-weight and buoyancy buoyancy and applied self-weight load, of the resultant the force Vis The The distribution of the contact pressure is determined by the equilibrium equilibrium by the determined is pressure contact of the distribution The Due to arise. stresses large infinitely of spread edge foundations, the At of distribution the spread foundations, rigid rectangular and For circular Foundation Systems for High-Rise Structures High-Rise for Systems Foundation σ 0

= Stress trapeze method centric loads on elastic isotropic half-space isotropic elastic on loads centric of aresult as foundations rigid under pressure contact the of Distribution π b b 2 2 2 Σ ⋅ Rectangular foundation V and V and a ⋅ b ⋅ 2 a  11 Σ V −⋅ M, without considering deformations of the building building of the deformations considering without M, V y 4 2 ab ⋅ ⋅ V x 2 a 22  x − 2 ⋅ y Figure 3.9 σ 0 Circular foundation = 2 R ⋅ π V1 R V . R V 2 ⋅ r 1 − R r 2 23 ]. Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4

subface, the torques M the subface, of the of gravity center at the force Vacts resultant the If Equation 3.8. subface of( the of gravity center the with corresponds point zero where the used, is system coordinate rectangular arbitrarily an of coordinates, axes Equation 3.7 For the foundation, used. is Figure 3.10 centrifugal moment I moment centrifugal with conjunction in equation following to the according performed is pressure contact maximum of the determination the not and applicable, are 3.9 through Equations 3.7 case, this In gap occurs. open An superstructure. subsoil- system by not the absorbed are which occur, stresses tensile to Equation 3.9. according pressure contact the If the x- and the y-axis are the main axes of the coordinate system, the the system, coordinate of the axes main the are y-axis x- the the and If If the eccentricity of the resulting forces V is too large, theoretically theoretically large, too Vis forces resulting of the eccentricity the If σµ σ σ σ Table 3.2 0, 0 0 0 ma =+ = =+

x V V V A A A Coordinate system for the contact pressure (stress trapeze method). trapeze (stress pressure contact the for system Coordinate =⋅

M MI : I V A y y yx II xy ⋅−

⋅+ x ⋅− x xy M MI x I

I

x = = xy x xx A 0. Equation 3.7 is simplified to the following the following to 3.7 simplified is 0. Equation M 2 ⋅ ⋅ y y

y

= ⋅+ x 0. The result is a constant distribution of distribution aconstant is result The 0. S MI y y xy II e xy x ⋅− ⋅− Figure 3.10 V e y MI I xy yx 2 ⋅ y ⋅ ) [ Spread foundations Spread y x 24

]. (3.10) (3.7) (3.8) (3.9)

37 Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 38

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation

Table 3.2 Coefficients μ for determining the maximum of the soil contact pressure 0.32 3.70 3.93 4.17 4.43 4.70 4.99 0.30 3.33 3.54 3.75 3.98 4.23 4.49 4.78 5.09 5.43 0.28 3.03 3.22 3.41 3.62 3.84 4.08 4.35 4.63 4.94 5.28 5.66 0.26 2.78 2.95 3.13 3.32 3.52 3.74 3.98 4.24 4.53 4.84 5.19 5.57 0.24 2.56 2.72 2.88 3.06 3.25 3.46 3.68 3.92 4.18 4.47 4.79 5.15 5.55 0.22 2.38 2.53 2.68 2.84 3.02 3.20 3.41 3.64 3.88 4.15 4.44 4.77 5.15 5.57 0.20 2.22 2.36 2.50 2.66 2.82 2.99 3.18 3.39 3.62 3.86 4.14 4.44 4.79 5.19 5.66 0.18 2.08 2.21 2.35 2.49 2.64 2.80 2.98 3.17 3.38 3.61 3.86 4.15 4.47 4.84 5.28 0.16 1.96 2.08 2.21 2.34 2.48 2.63 2.80 2.97 3.17 3.38 3.62 3.88 4.18 4.53 4.94 5.43 0.14 1.84 1.96 2.08 2.21 2.34 2.48 2.63 2.79 2.97 3.17 3.39 3.64 3.92 4.24 4.63 5.09 0.12 1.72 1.84 1.96 2.08 2.21 2.34 2.48 2.63 2.80 2.98 3.18 3.41 3.68 3.98 4.35 4.78 0.10 1.60 1.72 1.84 1.96 2.08 2.21 2.34 2.48 2.63 2.80 2.99 3.20 3.46 3.74 4.08 4.49 4.99 0.08 1.48 1.60 1.72 1.84 1.96 2.08 2.21 2.34 2.48 2.64 2.82 3.02 3.25 3.52 3.84 4.23 4.70 0.06 1.36 1.48 1.60 1.72 1.84 1.96 2.08 2.21 2.34 2.49 2.66 2.84 3.06 3.32 3.62 3.98 4.43 0.04 1.24 1.36 1.48 1.60 1.72 1.84 1.96 2.08 2.21 2.35 2.50 2.68 2.88 3.13 3.41 3.75 4.17 0.02 1.12 1.24 1.36 1.48 1.60 1.72 1.84 1.96 2.08 2.21 2.36 2.53 2.72 2.95 3.22 3.54 3.93 0.00 1.00 1.12 1.24 1.36 1.48 1.60 1.72 1.84 1.96 2.08 2.22 2.38 2.56 2.78 3.03 3.33 3.70 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 0.20 0.22 0.24 0.26 0.28 0.30 0.32

eb/b Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 E stiffness ing of Winkler. half-space on the founded is b, which width the with tion founda strip and elastic long infinitely arbitrary, moment for an bending design of railwaytracks. design [ by Winkler century nineteenth the in formulated of was shape change the relation with in reaction subgrade prepared The method. modulus reaction the subgrade using by time first for the account into wastaken structure and soil between interaction an Historically, 3.3.2.4 Figure 3.11 where: pressure contact the where at point any model, aspring is of Winkler, half-space springs. vertical free-movable independent, the between interactions not the consider does approach behavior subsoil cal for the mechani linear due to the aspring as interpreted be can modulus reaction of proportionality k

The curve of the bending moment of the strip foundation with the bend the with foundation strip moment of the bending of the curve The of the curve the to theory, itdescribe possible is beam-bending the Using According to Winkler According The double differentiation of Equation 3.12 results in of Equation 3.12 results double differentiation The σ

Mx σ dM k 0s 2 s 0 dx s () ()

xk Subgrade reaction modulus method modulus reaction Subgrade

σ 2 (x = = = Spring model for the subgrade reaction modulus method. 0 =− is proportional to the settlement s(Equation 3.11). settlement to the proportional is constant The =⋅ subgrade reaction modulus [kN/m modulus reaction subgrade [kN/m pressure contact settlement [m] settlement ) =− b EI

× b qx sx ⋅⋅ I is given by given I is () () s ds is called the subgrade reaction modulus. The subgrade The subgrade modulus. reaction subgrade the called is

dx =− 2 (x , 2 EI the elastic model of the subsoil, which is also called called also is which subsoil, of model the elastic the ) B

⋅⋅ V 1 ds dx 4 (x 4 V 2 ) ] 2

( Figure 3.11 V 3 3 ] 25 ). However, this method ). method However, this Sp be El ]. It was created for the for the ]. wascreated It Spread foundations Spread as am ring tic s (3.12) (3.13) 3.11

39 - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 strip foundation, the distribution of the contact pressure pressure contact of the distribution the foundation, strip long 3.16 infinite solved. For be an can Equation conditions, boundary of s(x), 3.16 Equation of elimination number the and For follows. alarge 40 ( spread foundation the beside settlements it notto determine is possible method, modulus reaction subgrade the With distances. column large of with slender, spread foundations relatively limp able calculation for the suit mainly therefore is It pressures. contact of neighboring influence following parameters: to 3.19. Equations 3.17 according through result forces shear of the moment M(x), distribution the bending ofand tion the

described by Figure 3.12

The action q(x) corresponds to the contact pressure pressure q(x) contact to the action corresponds The The subgrade reaction modulus method does not take into account the the account into not take does method modulus reaction subgrade The on the depends It parameter. not is asoil modulus reaction subgrade The With the elastic length L given as Lgiven length elastic the With • • •

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation Qx qx L M(x) σ dM Dimensions of the spread foundation of the Dimensions compressible oflayer the Thickness subsoil of modulus the Oedometric 0 () 4 dx = () =+ 4 44 (x 2b =− = 4E =± ⋅⋅ ) kb ⋅⋅ V VL ). += s σ 4 ⋅ V B 2 0s ⋅ 4M L () ⋅⋅ xb I ⋅⋅ L ⋅⋅ ec ec ec

− (x − ⋅= − L x L x L x )       os −⋅ 0 os os ks L x

L x L x

() − xb si si n ⋅= n L x L x      

EI

B ⋅⋅ ds dx 4 (x 4 )

σ 0 σ (x), which can be (x), be can which 0 (x), distribu the (3.15) (3.19) (3.17) (3.16) (3.18) (3.14) - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 Figure 3.13 7. EC regulations technical valid currently the to according defined are of spread foundations ability service and for stability analysis geotechnical the section following the In 3.3.3 behavior. mechanical soil basic this consider computer programs Powerful reality. in not occur do peaks stress these subsoil, of the effect plasticizing to the Due tion. the spread founda edge of the at result peaks stress large infinite retically of equations. system indeterminate statically for the available solutions are no closed cases, For most computer programs. using examined normally are conditions boundary geometric and load situations method. modulus stiffness to the according dation arise. deformations same The trough. settlement modeled isotropic elastic, linear moment of the bending the with linked is spread foundation modeled elastic linear moment of the bending the method, modulus stiffness the In [ spread foundation of the point arbitrary of an settlement on the considered is pressures of adjacentcontact influence the because method, modulus reaction subgrade the than more accurately interaction structure to Ohde (1942) soil– the according method modulus describes stiffness The 3.3.2.5 Figure 3.12 The assumption of infinite elastic subsoil has the consequence that theo that consequence the has subsoil elastic of infinite assumption The complex with spread foundations practice, engineering geotechnical In Figure 3.13

Geotechnical analysis Geotechnical

Stiffness modulus method

method. modulus reaction subgrade the to according settlements the of Distribution Distribution of the settlements according to the stiffness modulus method. modulus stiffness the to according settlements the of Distribution represents the distribution of the settlement of aspread foun settlement of the distribution the represents V V Se Se ttlemen ttlemen Spread foundations Spread ts ts 19 ,

26 41 ]. - - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 42 the analysis of the limitation of the open gap, which is defined for the for defined is gap, open which of the limitation of the analysis the foundation. spread the of lower of moves the center edge surface to the tilting the strength, shear decreasing and rigidity a decreasing With subsoil. of the strength shear to Equation 3.22: according estimated is action value stabilizing of the design the and Equation 3.21, foundation: the spread edge of the edge at tilting on afictional based compared are forces stabilizing and destabilizing The mechanics. body rigid of the on aprinciple based is of overturning because of loss balance against spread foundation. of the lowerover surface entire the compressive a stress creates width core first the force in aresulting Thus, [ in approach described is gap. open This an with part asmall only has spread foundation of the lower the surface that means That core width. second the into forces of the resultant wasdone by the applying turning of over because of loss balance against Up to of now, safety analysis the 3.3.3.1

The analysis of the stability includes stability of the analysis The Therefore, this analysis itself is not sufficient. It was complementedIt by was not is sufficient. itself analysis this Therefore, the and rigidity on the depends edge tilting of the position the reality, In to according estimated force is value destabilizing of the design The of safety analysis the regulations, technical current to the According includes serviceability of the analysis The • • • • • • •

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation EE EE EE Analysis of settlements and differential settlements differential and of settlements Analysis displacements horizontal of Analysis gap open of the limitation the and rotation foundation of the Analysis buoyancy against of safety Analysis failure base against of safety Analysis sliding against of safety Analysis of overturning because of loss balance against of safety Analysis stb, ds ds

t,d t, ds ds balance because of overturning of loss against safety of Analysis ≤ =⋅ =⋅ G,dst,k tb tb ,d ,k

γ G,stb γγ G,dst

+⋅ E Q, ds t, kQ ,dst

27 (3.20) (3.22) (3.21) , 28 ]. - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 cases:

3.3.3.2 ( corewidth second applied the into to be loads has variable force of the the resultant and width core first applied the into to be loads has manent to According state. limit serviceability where: horizontal displacements. the regarding verified to be has state limit serviceability the considered, is pressure passive earth the If pressure. passive earth and of resistance slide consisting resistance, total the than havespread smaller foundation to be of the lower to the surface parallel forces The to Equation 3.23. according calculated is GEO-2) state (limit sliding against of safety analysis The

Figure 3.21 The sliding resistance is determined according to the three following following three to the according determined is resistance sliding The •

•

HR fully consolidated subsoil: fully subjacent, the in and spread foundation the gap between the in Sliding where: example, in the arrangement of a foundation cut-off: of afoundation arrangement the in example, for soil, consolidated fully the through gap passes the when Sliding where: R R dd

R R d d ≤+ Analysis of safety against sliding against safety of Analysis

φ′ δ

V = p, V d = d k = k Vt Vt

= ). k k γ R γ R R, ⋅ϕ spread foundation [°] foundation spread = = = = γ ⋅δ R R, k R, h an p, characteristic friction angle for the subsoil under the the under subsoil for the angle friction characteristic [kN] loadings value vertical of the characteristic [°] friction of base value angle of the characteristic [kN] loadings value vertical of the characteristic an h p, γ h k d R,

h ′ +A

⋅ c ′

[ 10 ], the resultant force of the per force of the resultant ], the Spread foundations Spread (3.25) (3.23) (3.24)

43 - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 of the bearing capacity R capacity bearing of the value design the if guaranteed is failure base against of safety analysis The 3.3.3.3 foundation. of the phase service the and construction the in sible stages pos all during exists pressure earth passivethe whether verified it be must Basically, pressure. to 50% passive earth possible of the limited should be pressure passive earth the deformations, to horizontal Due enough. deep φ′ friction of base value angle of the characteristic the angle friction friction of base angle of the in shown is of aspread foundation failure bearing be factorized with the bearing capacity factors N factors capacity bearing the with factorized be cohesionc the and foundation the dof depth embedment the foundation, bof the width the considers capacity [ state deformation plane plastic, in ideal capacity bearing the of figure failure of the moment equilibrium the V 44

R [ standard tal inciden the in found be can information Detailed spread foundation. of the depth embedment the and dimensions (density, the parameters), ties shear d n,k . The characteristic value of the angle of base friction should be should be friction of base value angle of the characteristic . The

A passive earth pressure can be considered if the spread foundation is is spread foundation the if considered be can pressure A passive earth concreted are that For spread foundations The resistance of the bearing capacity is determined by the soil proper soil by the determined is capacity bearing of the resistance The . R

• is calculated analytically with a trinomial equation, which is based on based is which equation, atrinomial with analytically calculated is

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation R d where: Sliding on water-saturated subsoil due to very quick loading: quick due to very subsoil on water-saturated Sliding R is calculated according to Equation 3.27. The principle scheme of a scheme to Equation 3.27.principle The according calculated is d

d = Analysis of safety against base failure base against safety of Analysis

= R c A γ c A ′ R, Ac u n,

γ

v k R, ⋅ 29 φ′ = = h = soil [kN/m soil =

u area of the load transmission [m load of transmission the area characteristic value of the cohesion of the subsoil [kN/m subsoil value cohesionof of the the characteristic Area of the load transmission [m load of transmission the Area Characteristic value of the undrained cohesion of the sub cohesionof the value undrained of the Characteristic of the soil. For prefabricated spread foundation elements elements spread Forfoundation prefabricated soil. of the , 30

]. The characteristic resistance of the bearing capacity capacity bearing of the resistance characteristic ]. The d 2 is bigger than the design value of the active force value active of the design the than bigger is ] δ is the same as the characteristic value of the characteristic the as same the is 31 ′ of the subsoil. All three aspects have to aspects three All subsoil. of the ]. The trinomial equation of the bearing bearing of equation the trinomial ]. The in situ in 2 b 2 ] , N Figure 3.14 , the characteristic value characteristic , the ] δ d should be set to 2/3 to 2/3 set should be , and N , and c . : δ

≤ (3.26) (3.27) 35°. 2 - - ] - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 following boundary conditions: level. The density density level. The Figure 3.14 foundation level. The bearing capacity factors N factors capacity bearing level. The foundation Table 3.3 subsoil of the of friction angle on the where: The parameters of the bearing capacity factors N factors capacity bearing of the parameters The The density density The • • • • •

Ra NN NN NN Basic values of the bearing capacity factors: N factors: capacity bearing of values the Basic Parameters for the base inclination: inclination: base for the Parameters inclination: for landscape Parameters i for load inclination: Parameter parameters: Shape n, dd bb cc k2 =⋅ =⋅ =⋅

= . Rankine-zone of the failure body; 8, Prandtl-zone of the failure body. failure the of Prandtl-zone 8, body; failure the of Rankine-zone friction of angle the on depends form the surface, sliding 5, floor; cellar 4, pressure; contact ing result 3, area; 2, wall; 1, Reinforced foundation strip of a figure failure Bearing ′ 0c 0b ⋅ 0d bb γ vi ′ vi vi 1 ⋅ describes the density of the subsoil above the foundation above foundation subsoil ofthe the density the describes 2 () ⋅⋅ γγ ⋅⋅ ⋅⋅ cc γ 3 bb dd 7 2 ⋅⋅ describes the density of the subsoil underneath the the underneath subsoil of the density the describes λξ λξ λξ ′ ⋅+ ⋅ Nd ⋅ ⋅ ν b c b b1 , b d φ ν ; 6, passive Rankine-zone of the failure body; 7, body; active failure the of Rankine-zone passive ; 6, d , ν c 8 γ γ ⋅+ 2 1 Nc , ϕ dc b , c , i φ 1 d ’ and are calculated according to according calculated are ’ and , i 5 ′ ξ ⋅ b c λ N , b ξ , 4 d , λ 6

d ξ b , c , N λ c b0 d Spread foundations Spread , N , and N , and b0 , N d0

, N d d0 c , N c0 consider the the consider c0 depend depend (3.28)

45 - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 parameters i parameters area. 20% whole of base the than not bigger are parts open the if analysis, for the used may be dimensions external the parts, a is applied, a dimensions of reduced gravity. center the The in to load be has resulting The in summarized are parameters shape applicable the geometry, standard For the spread foundation. sions of the 46 where where strip foundation foundation strip angle by the determined is forces acting oftion the in shown is load for inclination the eters in shown is load inclination ′ and b and

If eccentric forces have to be considered the base area has to be reduced. reduced. to be has area base havethe considered forces to be eccentric If The shape parameters parameters shape The Forces T Forces Foundation Systems for High-Rise Structures High-Rise for Systems Foundation bb aa mm ′ ′ =− =− m =+ ′ a are calculated according to Equations 3.29 and 3.30. Basically Basically 3.30. and to Equations 3.29 according calculated are Rectangle Strip Floor plan Table 3.4 Square/Circle = a k 2e that are parallel to the foundation level are considered by the by the considered level are foundation to the parallel are that 2e ⋅⋅ b > Table 3.3 (N Foundation widthN 2 1 co , i b a and + a + b d0 d sm

, i

–1) tan b a b 2 a ω ωω ′

′ ′ ′ c for the load inclination. The definition of the angle of the of angle the of definition The load for inclination. the

Shape parameters and and =

90°. Basic values of the bearing capacity factors capacity bearing the of values Basic ′

φ b > 10 m − b si ν b 0.7 1.0 b ′ n ν , respectively. For spread foundations with open open , respectively. with For spread foundations . , 3 = b0 b Figure 3.15 2 ν ⋅ d b 1 2 a , ′ ′

ta + + Foundation depth ν n c 1 b a b a take into account the geometric dimen geometric the account into take 2 1 + ν ′ ′ ′ ′   

i + b 45 a Table 3.4 1.0 ′ ′

ν sin ⋅ d si + . The determination of the param determination . The n

φ ϕ 2 ϕ Tables 3.5    ⋅ e ν v v πϕ N dd dd c ⋅ N N ( . ta ⋅− ⋅− d0 n N N φ 1.0 d0 d0

≠ − − 0 0 1 1 0) Cohesion and and 1 1 ω N ( ta d0 Figure 3.16 10 ν n +⋅ c 3.6 − ϕ ( 1 φ 1.2 1.0 N . 2

. The orienta . The c0 = 0) b a ′ ′ ). For a (3.30) (3.29) (3.31) - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 Figure 3.16 in shown is inclination for landscape parameters of the determination The slope edge. to the parallel to be has foundation of the axis longitudinal the and subsoil β slope inclination on the depend parameters The inclination. for landscape Figure 3.15 . The slope inclination has to be less than the angle of friction of friction angle the than less to be has slope inclination . The δ Direction δ Table 3.5 An inclination of the landscape is considered by the parameters parameters by the considered is landscape of the inclination An

δ < > ( SS 0 0 + )

Definition of the angle of the load inclination. load the of angle the of Definition Angle Angle Parameter i Not necessary, becauseof Table 3.6 Figure 3.17 co s. δδ ω ⋅⋅ for an oblique acting load. acting oblique an for (1 – tan () 10 γ

1 − Parameter i . b' d i for load inclination if if inclination load for 04 i b and

δ i b ) m 06 + .. Table 3.7 1 40 +⋅ T i of the load inclination if if inclination load the of k 028 ω δ ϕ φ (–) δ

= 0 . co φ′ s. δδ 1.0

> i ⋅⋅ d () 10 0 γ (1 – tan 1 − . d 05 0244 i .. d a' + δ φ′ ) 05 m Spread foundations Spread

= 00 i 0 c .. 1 30 − + Ac 04 T ′ ϕ k ⋅ iN dd N ⋅− φ′ λ d0 b i of the of the c , 0 − λ 1

d 1 , 47 λ c

Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 48 Figure 3.17 is as follows. The weighting resistance. failure the shear on influence to their according weighted may be parameters soil individual the case, this average.tic In arithme 5° of the more than do not vary of friction angles individual the of values the if averaged parameters soil with to calculate permissible is layer. one soil it in formed For is layeredconditions, soil surface sliding have investigated. to be bodies failure of both doubt, cases In opposite direction. the in forms body failure inclination base of the angle The forces. horizontal the inclination in shown is inclination base oftion the inclination base the and subsoil the ( inclination base

The base inclination is considered by the parameters parameters by the considered is inclination base The The direct application of the defined equations is only possible if the if possible is only equations defined applicationof the direct The Foundation Systems for High-Rise Structures High-Rise for Systems Foundation

Eccentric, oblique loaded strip foundation on aslope. on foundation strip loaded oblique Eccentric, φ φ Table 3.8 Case φ φ Table 3.7 Case

α = >

is positive, if the failure body forms out in the direction of direction the out in forms body failure the if positive, is = > 0 0 0 0

Table 3.8

Coefficient Coefficient (1 – 0.5 tan Parameters Parameters e − 0.045 — — λ ξ · b b

α

·

tan ), which depend on the angle of friction of friction angle on the depend ), which β ξ φ ) δ i b b' λ of the base inclination 6 ( i T e for landscape inclination for landscape + b k ) (1 – tan N k α e of the spread foundation. The defini The spread foundation. of the − 1.0 λ 0.045 d Figure 3.18 1.0 β ξ ) · d

1,9 α

·

tan φ Ne d0 ⋅ 1 – . The angle of the base base of the angle . The β − N 0.4 tan e 0 1 . − d0 0349 λ − d 0.045 c 0.0068 − α ⋅⋅ βϕ 1 is negative, if the the if negative, is ξ tan · c

ξ β α

b ·

, tan − α ξ φ 1 d , ξ c for the for the φ ’ of - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 3.42 have applied. to be through 3.39 Figure 3.19 ( 3.38 through 3.32 Equation to body according the failure to define recommended φ Figure 3.18 . To determine whether the failure body has more than one layer, more itthan is has body failure the . To whether determine Authoritative for the sliding surface is the average of the angle of friction of friction average the angle is of the surface sliding forAuthoritative the • •

ϑ failure body failure of the area cross-section the layers in individual of the percentage the average to related the cohesionare and of friction average angle The body failure of the area cross-section the layers in individual of the percentage to related the is average density The 1 α =°

45 Determination of the failure body. failure the of Determination Angle of the base inclination inclination base the of Angle −− T Figure 3.19 δ k ϕ 22 ϑ N N 3 k h,k () b N εβ 1 k + ϑ b 2 r 2 α ). For simple cases ( ). For simple cases

( ν z + ) ϑ 1 r 1 α . γ 1 γ α 2

l , = ϕ , c d

β

=

Spread foundations Spread δ

= 0), the Equations 0), Equations the β d (3.32)

49 Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 and the parameters parameters the and

where: where: 50 where

failure. base regarding capacity bearing of the analysis with calculation ( ered

For spread foundations at slopes, the foundation depth d depth foundation the at slopes, For spread foundations Foundation Systems for High-Rise Structures High-Rise for Systems Foundation dd ν= ϑϑ ϑ lr να ϑ ϑ r rr rb 12 2 2 ′ = Figure 3.20 1 3 23 2 =° =⋅ = = =+ si =° =° =° == si 180 90 1 n 2c n 45 45 45 ⋅ ε ′ ⋅° co ° ⋅ 2 ε e co

1 0. os =− 0.0175 s( − ++ −− +− =− co 8s 45 ss ϑ    ϕ 2 α ϕ 22 ϕ 22 ⋅⋅ s b 1 45 si si °+ ϕ β ⋅⋅ ⋅+

′ si νϕ si + ). In addition, it is necessary to carry out acomparative to carry it necessary is addition, ). In si n n

ta β = n n ta in ϕ δ ϕ n () () n + ϕ ϕ β εδ 2 εδ 0 and d 0 and −− ) λ n () ϑ 2 2 ϑϑ b

ϕ 2 β ϑϑ

3 , − − 23 12

   λ d

,

λ ′ c

for landscape inclination have consid to be inclination for landscape

= d. The smaller resistance is the basis of the of the basis the is resistance smaller The d. ′ (Equation 3.43) (Equation 3.43) (3.36) (3.37) (3.34) (3.35) (3.38) (3.40) (3.39) (3.33) (3.42) (3.43) (3.41) - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4

where: T forces shear Acting ensured. is forces of the transmission the if considered be side) atonly the forces can (friction forces buoyant to the water. force of compared the big enough is Shear structure of weight the net the proof that the is equation This 3.44. Equation using performed is UPL) state (limit buoyancy against of safety analysis The 3.3.3.4 Figure 3.20 • •

γ γ G Q γ G GQ TE T Q,dst G,stb G,dst for example, starting at the end of a horizontal spur in dependency to dependency in spur end of at ahorizontal the starting for example, subsoil, ajoint of the in pressure earth componentactive of the Vertical (Equation 3.45) E pressure earth component active of the Vertical active earth pressure E pressure earth active component of the horizontal on the depending structure ing kz dst,k stb,k dst,rep ds k

=⋅ t,k Analysis of safety against buoyancy against safety of Analysis

ηδ

⋅+ Spread foundation on aslope. on foundation Spread

γγ G,dst T ======k δ ah,k partial safety factor for permanent stabilizing load stabilizing for factor permanent safety partial shear force shear load stabilizing permanent load (buoyancy) vertical destabilizing permanent partial safety factor for permanent destabilizing load destabilizing for factor permanent safety partial representative variable destabilizing vertical load vertical destabilizing variable representative partial safety factor for variable destabilizing load destabilizing for factor variable safety partial b N ⋅ ta k ds n t,re pQ a

⋅≤ ,dst ah,k 0.8 GT as well as the angle of wall friction friction of wall angle the as well as stb,k . s s ⋅+ γγ G,stb k may be may k ⋅ G,stb Spread foundations Spread

av,,k β on a retain

d (3.44) (3.45)

d' 51 δ - a

Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 ond core width for a rectangular spread foundation. for arectangular ond corewidth used. is Equation 3.50 foundations spread to Equation 3.49. according For circular determined be layouts can for rectangular corewidth second The spread foundation. of the line center the across occur gap open cannot an so core width, second the in loads are variable the loads and permanent of the resultant the that guaranteed be it should Furthermore, 3.48 used. is Equation spread foundations cular to Equation 3.47. according For determined cir be can spread foundations width for rectangular core first The not occur. gap open does an that means which width, core first the into limited to be loads has dead of the resultant considered. have rates to be displacement behavior material time-dependent example, for cases, special In deformations. differential as well as displacements and referto absolute deformations states limit serviceability the Generally, 3.3.3.5 52 Figure 3.21 For the design situation BS-P and BS-T, is and factor adjustment the BS-P situation design For the without any shear forces T forces shear any without given is buoyancy against safety the BS-A, situation design in that mined deter to be it has structures, For permanent factors. adjustment by the be reduced butto has it into account, taken be cohesion can cases justified For the design situation BS-A, the adjustment factor is is factor adjustment the BS-A, situation design For the

For the analysis of foundation rotation and limitation of the open gap, the gap, open the of the limitation and rotation of foundation analysis For the The smallest possible horizontal earth pressure min E min pressure earth horizontal possible smallest The Foundation Systems for High-Rise Structures High-Rise for Systems Foundation TE of friction of friction angle the and pressure earth componentactive of the horizontal the kz

=⋅ limitation of the open gap open the of limitation and rotation foundation of Analysis

ηϕ Limitation of the eccentricity. the of Limitation ah,k Resulting forc φʹ ⋅ of the subsoil: of the e ta

b n ′ b

L /6 e k b . L /6 e a Figure 3.21 b y L x e 1. Corerange 2. Corerange shows the first and the sec the and first shows the

ye b b B B /6 /6 x η ah,k z

bB = has to be used. used. to be has 0.90. Only in in Only 0.90. η z

= (3.46) 0.80. 0.80. - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4

damage factors for the angular distortion as a result of settlements [ of settlements a result as distortion angular for the factors damage [ for constructions settlements or differential settlements the acceptable about information to provide it difficult is tion, z between is [ with accordance in conducted are of spread foundations for settlements determinations The 3.3.3.7 have considered. loads, to be or unique infrequent as well as loads, variable loads and Permanent displacements. horizontal if: observed, is displacement of horizontal analysis the forGenerally, spread foundations 3.3.3.6 edge. atilting as dation spread foun of the one edge out by using carried is of overturning because to [ according mandatory observed. is eccentricity acceptable the if expected be can foundation of the distortions respectively, no incompatible cohesive soils, stiff and soils non-cohesive Due to the complex interaction between the subsoil and the construc the and subsoil the between complex to the interaction Due possible the to analyze it necessary is not true, are arguments these If gap is open of the limitation and rotation of foundation analysis The on medium-dense, founded are which foundations, strip and For single • •

   e0 e0 x a earth pressure are considered. are pressure earth characteristic of the one-third not level more and than foundation the in resistance sliding characteristic of the tively, two-thirds only respec cohesive soils, stiff and soils non-cohesive For medium-dense, pressure. apassive earth ing consider without performed is sliding against of safety analysis The x ≤⋅ ≤⋅ ee a e

+= Analysis of settlements and differential settlements differential and settlements of Analysis    Analysis of horizontal displacements horizontal of Analysis .5 .2 2 y b + 9r 5r    = y b and z b and b 6 1

e   

32 2 = ] 9 1 . Normally, the influence depth of the contact pressure pressure contact the of depth influence the . Normally,

= 2b. 10 ] , if the analysis of safety against loss of balance of loss balance against of safety analysis the , if 33 ] . Figure 3.22 Spread foundations Spread indicates the the indicates 33 (3.50) (3.47) (3.48) (3.49) –

35 53 ]. - - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 sure sure a simple comparison between the base resistance resistance base the between a simple comparison of consists cases standard in of spread foundations analysis simplified The 3.3.3.8 54 to Equation 3.52. according performed is spread foundations for circular analysis to Equation 3.51. The according [ ture struc for the harmless is tilting occurring the that to check has inclination Figure 3.22

h More detailed information can be found in [ in found be can information More detailed E 3.52: and Equations 3.51 In against of safety analysis the structures, of high-rise tilting the Regarding V f r s and f and m d

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation

Vh Vh = σ

= = 33 bE rE E,d ds ds Height of the center of gravity above the foundation level above foundation the of gravity center of the Height Design value of the vertical loads value vertical of the Design 3 Modulus for the compressibility of the subsoil of the compressibility for Modulus the 3

⋅⋅ ⋅⋅ ] (Equation 3.53). For spread foundations with the area A area the with For spread foundations (Equation 3.53). ⋅ ⋅ Simplified analysis of spread spread of analysis Simplified foundations in standard cases in standard foundations . The analysis for rectangular spread foundations is performed performed is spread foundations for rectangular analysis . The

y Damage criterion.

m = m 10 f f 1 Tilting coefficients Tilting y y ≥ ≥ Leaning t 1 1

100 1 ower ofPisa 200 1 Considerable crack Damage limitforbuilding Sa fe 300 ty limitforbrickwallsh/1<1/ rigid building Limit ofvie 1 Difficulties forcraneswithabigrange Limit forfirstscratchesinload-b 400 1 500 1 w formisaglinmentoftal s an Sa s inload-b 600 fe y kindofcrac 1 ty limitinordertoa frame Damage limitforinfille 700 s 1 earing wall 33 s 800 1 sensitive machiner Limit b ] and [ ] and σ ks 4 R,d 900 1 and the contact pres contact the and oundar s earing wall l 1000 36 void 1 ] . y for d y s = a (3.52) (3.51) × b b - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 cohesive soils considers the design situation BS-P. For the design situation situation design For the BS-P. situation design the considers cohesive soils [ given were values characteristic tables, of these editions earlier in that to notice it essential is tablevalues, current applicationof For the the analyzed. to be has ability service the loads occur, eccentric If (no loading eccentricity). acentral with excavationto of the below adepth due unloading the 1.4 be times can raise The raised. be can values tabular [ foundations for single used be also can values tabular The tables. in specified are foundations strip foundation widths that are bigger than the width b width the than bigger are that widths foundation (SLS). For settlements of the analysis the and (ULS) failure base against Figure 3.23 spread foundation. of the width increasing an with decreases pressure tact con admissible the analyzed, is ULS the only If spread foundation. of the width increasing an with increases pressure contact admissible the lyzed, ana is SLS the only If settlements. the and failure base of the examination cases. These standard cases include: cases standard These cases. standard applied in be can state, limit serviceability of the analysis the as A or

pressure decreases because of settlements. because decreases pressure The simplified analysis of the ULS and SLS of strip foundations in non- foundations strip of SLS and ULS the of analysis simplified The foundations strip refer to detached tables the in values settlement The level more is than foundation the If The design values of the contact pressure pressure contact of values the design The The design values of the contact pressure pressure contact of values the design The • • • • • • •

ʹ σσ

= rule tan the observes pressure contact of the resultant of the inclination The procedures tive or other by construc it assured applied is if be only can pressure Passive earth soils cohesive in no water loads; pore pressure dynamic or mainly dynamic regular No 2 m) level (minimum foundation below the foundation the width of the twice intoof depth a the subsoil of strength Sufficient layers soil and landscape horizontal almost an and foundation of the lower surface Horizontal is observed is of overturning because of loss balance against of safety analysis The observed is pressure contact of the resultant of the eccentricity admissible The forces) vertical tic tact pressure; H pressure; tact E, a dR ʹ ≤

× b shows the two fundamental demands for an adequate analysis adequate analysis for an demands fundamental two shows the ʹ ,d , the analysis of safety against sliding and base failure, as well well as failure, base and sliding against of safety analysis , the δ

= H 10 k /V ]. k

= k 10

characteristic horizontal forces; V forces; horizontal characteristic ≤ , 0.2 ( 0.2 37 , 38 δ ].

= ≥ inclination of the resultant of the con of the resultant of the inclination 2 m under the surface. the 2 m under 2 m below the surface on all sides, the the sides, on all surface m below the σ R,d σ R,d are based on the combined combined on the based are for simplified analysis of analysis for simplified s , the acceptable contact contact acceptable , the Spread foundations Spread k

= characteris (3.53)

55 ------Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 to Equation 3.55. The compression ratio 3.55. D The to Equation according n, porosity by the determined Dis compactness The dense. or dense, medium loose, is subsoil the whether Ddescribes compactness [ to Equation 3.54 according it determined is of 10% 60% fractions and and of passing area the in distribution size 56 forms of the soil groups are explained in explained are groups soil of the forms in requirements the soils non-cohesive bor b width the than bigger be must distance level. The groundwater the and foundation b width if extrapolated may values be tabular loads the early. For eccentric lin interpolated may values be Intermediate loads. applicable for vertical side”. “on are are safe values values the tabular tabular the BS-T The Figure 3.23 SE, SW, SI, GEGW, SE, GE, SU, GU, ST, Table 3.9 to DIN 18196 Soil group according GT, SU, GU GT ′

The coefficient of uniformity C uniformity of coefficient The < σ Foundation Systems for High-Rise Structures High-Rise for Systems Foundation 0.50 m. There must be a distance between the lower surface of the of the lower the surface between adistance be must There 0.50 m. De cont R, d si

act pressure gn Requirements for the application of the design values values design the of application the for Requirements soils

valueofth Maximum contact pressure pressure contact Maximum serviceability (SLS). serviceability Sig nifican UL ′ S of the foundation. For the application of the tables for tables application of For the the foundation. of the e t DIN 18196 Coefficient of according to uniformity b s > ≤ 3 3 C Sig u nifican SL σ S Compactness according to R,d DIN 18126 u describes the gradient of the grain grain of the gradient the describes taking into account the stability (ULS) and and (ULS) stability the account into taking ≥ ≥ Table 3.9 t cont R 0.45 0.30 ange ofacceptable D Table 3.10 act pressure pr F is the relation between the the relation between the is oundation widthb 39 must be fulfilled. The short The short fulfilled. be must ratio according to DIN18127 Compression ]. According to [ ]. According Se s ≥ ≥ . ttlemen D 98% 95% Pr σ R,d σ Base in non-cohesive in non-cohesive t R, d failur = f( Point resistance penetrometer b, q of thesoil c e ϕ [MN/m , ≥ ≥ 40 c, 7.5 7.5 ...) ], the ], the 2 ] - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 GU GT SU ST GW GE SI SW SE sible design values of the contact pressure pressure contact of values the sible design DIN 18196 according to form Short Table 3.10 [ density proctor

Table 3.12 additionally, limited to be has settlement the If failure. base against adequate safety an account into

minimum embedment depth d depth embedment minimum b width minimum the with soils non-cohesive in dations 41 For simplified analysis of strip foundations foundations strip of analysis For simplified The permissible design values of the contact pressure pressure contact of values the design permissible The • ]. The compression ratio is calculated using Equation 3.56. using calculated compression ratio is ]. The

C D D foundations have an aspect ratio a/b haveaspect an foundations by values design of the Increase u pr = =

= ma Explanation of the soil groups soil the of Explanation d d , the settlements are limited to 1–2 cm. limited are settlements , the ρ ρ 10 60 ma pr xn d

xn

Kies, schluffig Kies, tonig Sand, schluffig Sand, tonig Kies, weitgestuft Kies, enggestuft Sand, intermittierend Sand, weitgestuft Sand, enggestuft − ρ (Feinkornanteil: 5–15%) (Feinkornanteil: 5–15%) (Feinkornanteil: 5–15%) (Feinkornanteil: 5–15%) gestuft DIN 18196inGerman Long form according to pr mi − (density at optimal water content) and the dry density density water content) dry the (densityand at optimal n nn

Table 3.12 ≥ 0.50 m can be increased as follows: as increased be can 0.50 m 20% has to be applied. For the purpose of purpose applied. For to the be has Gravel, clayey (finefraction: 5–15%) Gravel, clayey (finefraction: 5–15%) Sand, silty(finefraction: 5–15%) Sand, clayey (finefraction: 5–15%) Gravel withawidespreaded grainsize Gravel withsmallgrainsizedistribution Sand withanintermittentspreaded grain Sand withawidespreaded grainsize Sand withsmallgrainsizedistribution Long form according toDIN18196inEnglish distribution size distribution distribution σ < in in R,d

2 for non-cohesive soils taking taking soils for non-cohesive resp. a Table 3.11 Table 3.11 ′ Spread foundations Spread /b ′

shows the permis shows the and σ < ≥ R,d

2; 0.50 m and the the and 0.50 m for strip foun strip for for 3.12 Table 3.11 , if single single , if (3.56) (3.54) (3.55)

57 ρ d - -

Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 For buildingswithan 2.00 1.50 1.00 0.50 1.50 1.00 0.50 For buildingswithan 2.00 foundation [m] depth ofthe Smallest embedment Table 3.11 58 to horizontal loads) have to be reduced if groundwater has to be considered: to be loads) has groundwater if haveto reduced horizontal to be in soils non-cohesive in tions Table 3.12 foundation [m] depth ofthe Smallest embedment resp. b and foundation width b 0.30 m embedment depth resp. b and foundation widthb 0.30 m embedment depth

The permissible design values of the contact pressure for strip founda for strip pressure contact of values the design permissible The • •

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation same as the foundation level foundation the as same level the is groundwater the if by values 40%, design of the Reduction level) foundation 2 munder level (minimum foundation the under in values the complies subsoil by values 50% in design of the Increase resp. 0.60 0.60 than bigger dis depth embedment the applied if it only is ′ ′

≤ ≤ ≥ ≥

d d 0.30 m 0.30 m pressure contact the of resultant avertical with failure hydraulic against safety Design values values Design Design values values Design pressure contact the of resultant avertical with 1–2 cm to settlements the of ≤ ≤ 0.50 m 0.50 m × b ′ σ σ R,d R,d 0.50 m Design valueofthecontactpressure 0.50 m Design valueofthecontactpressure for strip foundations in non-cohesive soils and sufficient sufficient and soils non-cohesive in foundations strip for for strip foundations in non-cohesive soils and limitation limitation and soils non-cohesive in foundations strip for 560 480 380 280 560 480 380 280 Table 3.11 1.00 m 1.00 m 700 620 520 420 700 620 520 420 Table 3.13 of thefoundation width of thefoundation width (even increased and/or reduced due reduced and/or (even increased 1.50 m 1.50 m 840 760 660 560 590 550 500 460 into a depth of twice the width width the of twice adepth into Tables 3.11 210 210 2.00 m 2.00 m 980 900 800 700 500 480 430 390 σ σ R,d R,d b b [kN/m [kN/m resp. resp. and 2.50 m 2.50 m 980 900 800 700 430 410 380 350 b b 2 2 ʹ ʹ ] ] independence 3.12 independence 3.00 m , if the the , if 3.00 m 980 900 800 700 390 360 340 310 × b b - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 may be increased by 20% if the aspect ratio is a/b ratio is aspect the by 20% if increased may be Tables 3.14 reduced due to horizontal loads and/or groundwater) bigger. are loads and/or due to horizontal reduced in values design the if used be only can sive soils is for the design situation BS-P. For the design situation BS-T, situation the design For the BS-P. situation design for is the sive soils due to groundwater)reduced bigger. are that may not collapse suddenly. may not collapse that through the principle, In expected. be can of 2–4 cm settlements used, in explained are groups soil of the forms short The of soil. types for given different early. are tables The lin interpolated may values be Intermediate loads. inclined and vertical applicable for are values side.” “on are safe values tabular the The tabular applied if the design values values design the applied if acteristic vertical (V vertical acteristic of char for due acombination to reduced groundwater)reduced to be need in shown soils non-cohesive in dations SE, SW, SI, GE SE, GE, SU, GU, Table 3.13 DIN 18196 according to Soil group GW, GT, SU, GU ST, GT The permissible design values of the contact pressure pressure contact of values the design permissible The The design values values design The cohein foundations strip of SLS and ULS the of analysis simplified The The design values of the contact pressure shown in shown pressure contact of values the design The The permissible design values of the contract pressure pressure contract of values the design permissible The • • • •

Reduction by the factor (1 factor by the Reduction Reduction by the factor (1 factor by the Reduction conditions are not true d depth embedment the provided level, that aboveis foundation the level groundwater the if by values 40%, design of the Reduction values design non-reduced the and bor b than smaller is level foundation the level and groundwater the between distance the If the foundation and if the aspect ratio is a/b ratio is aspect the if and foundation the ≥

3.17 0.80 m and d and 0.80 m Requirements forRequirements the increasing design values through are only applicable for soil types with a granular structure structure agranular with applicable types only for soil are DIN 18196 Coefficient of according to uniformity 3.17 k ) and horizontal (H horizontal ) and σ > ≤ R,d 3 3 ≥ (even reduced due to foundation width b (even due width to reduced foundation for strip foundations in cohesive soil shown in in shown cohesive soil in foundations for strip b; a separate analysis is only necessary if both both if necessary only is analysis aseparate b; ′ σ C Table 3.10 , it has to be interpolated between the reduced reduced the between interpolated to be , it has R,d u shown in shown − − Compactness according to DIN 18126 H H ≥ ≥ k k /V 0.65 0.50 D /V . If the the . If k k ) if H ) if Table 3.11 σ k Table 3.11 Table 3.11 ) ) loads as follows: as loads ) 2 R,d in all other cases other all in k Tables 3.14 is parallel to the long side to of the parallel is ratio according Compression 18127 σ ≥ ≥ to DIN ≥ R,d < 100% (even increased and/or and/or (even increased 2 resp. a 98% (even increased and/or and/or (even increased Table 3.12 (even increased and/or and/or (even increased 2 resp. a for non-cohesive soils for non-cohesive Spread foundations Spread D Pr σ σ R,d through R,d for strip foun strip for ʹ /b in in ʹ /b Point resistance penetrometer ʹ can only be be only can q

Tables 3.14 ʹ ≥ of thesoil c

Table 3.12 [MN/m < 2 3.17 ≥ ≥ 2. 15 15 > 2 m) 2 m)

are are 2 ] 59 - - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 60

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation Unconfined compressive 2.00 1.50 1.00 0.50 Unconfined compressive 2.00 1.50 1.00 0.50 soils the foundation Smallest embedmentdepthof Table 3.16 Table 3.15 the foundation Smallest embedmentdepthof strength q strength q Table 3.14 Unconfined compressive 2.00 1.50 1.00 0.50 of thefoundation Smallest embedmentdepth strength q Silt (ULaccording toDIN18126)consistency: Solidtosemisolid Mixed soils(SU*, ST, ST*, GU*, GT*according toDIN18196) Clay, silty soils(UM, TL, TM according toDIN18196)

Design values values Design Design values values Design u,k u,k

Design values values Design u,k [kN/m [kN/m [m] [m] [kN/m [m] 2 2 ] ] 2 ] σ σ R,d R,d σ R,d for strip foundations in mixed soils mixed in foundations strip for for strip foundations in clay, silty clay, in silty foundations strip for for strip foundations in silt in foundations strip for 120–300 120–300 Design value 350 310 250 210 250 220 200 170 Stiff Stiff contact pressure contact pressure Design values Design values pressure Consistency Consistency 300–700 300–700 350 310 250 180 120 σ Semi-solid Semi-solid R 390 350 290 240 520 460 390 310 , [kN/m d ofthecontact σ σ R,d R,d [kN/m [kN/m 2 ofthe ] of the > > 560 500 450 390 700 620 530 460 Solid Solid 700 700 2 2 ] ] Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 Main show, that the final settlements of a spread foundation can be 1.7can to of a spread foundation settlements show, final the Main that am Frankfurt in Clay. experiences The Frankfurt settlement-active very the in were founded of 150–180 m. All heights with were built skyscrapers other several 1980s, early and 1970s of 130 mheight the In wascompleted. and a storeys 30 with Commerzbank Tower 1969 in first and the structed, con storeys 20 was with 1961, building In first the high-rise. toered be were consid storeys 10–15 with buildings Germany, Main, am Frankfurt in 1960, Until buildings. high-rise of higher more and construction the to worldwide led has density population increasing decades, last the In 3.4 analysis. mechanical soil classic to the according b awidth with b by 10% width reduced at foundation meter per Tables 3.14 mogeneity of the Frankfurt subsoil. Frankfurt of the mogeneity [ loaded centrically is foundation the even if average of the settlement, up is to 20–30% tilting [ tures superstruc of the to lead atilting which settlements, Clay have differential of ments settle Final phase. construction end of at the the settlements the times 2.0 Nearly all high-rise buildings founded on spread foundations in Frankfurt Frankfurt in on spread foundations founded buildings high-rise all Nearly The design values values design The

FROM ENGINEERING PRACTICEFROM ENGINEERING FOUNDATIONS SPREAD OF EXAMPLES 43 15–35 ]. A statistical evaluation of the measurements indicates that this this that indicates measurements of evaluation the ]. Astatistical Table 3.17 Unconfined compressive 2.00 1.50 1.00 0.50 the foundation Smallest embedmentdepthof strength q through cm occurred [ occurred cm > 5 m the ULS and the SLS have to be checked separately separately have checked to be SLS the and ULS the 5 m

Design values values Design u,k 44 3.17 [kN/m σ [m] ]. The differential settlements result from the inho the from result settlements differential ]. The R,d Clay (TA according toDIN18196) for strip foundations in cohesive soil shown in in shown cohesive soil in foundations for strip (even increased due to the aspect ratio) have due aspect to to the be (even increased 2 ] 42 σ R,d , 43 for strip foundations in clay in foundations strip for ]. 120–300 210 180 150 130 Stiff contact pressure Design values Consistency 300–700 Semi-solid = 290 250 200 320 2–5 m. For foundations 2–5 m. For foundations σ Spread foundations Spread

R,d [kN/m ofthe > Solid 380 340 280 420 2 ] 700

61 - - - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 up to eight storeys. The whole complex has two sublevels and is founded on founded sublevels is whole and two complex The has up storeys. to eight towers building of 63 m two sists annex 70 m an respectively, and and high, 1959 from to 1963. con It wasconstructed Germany, Main, am Frankfurt in Company Assurance complex Zürich of the building high-rise The 3.4.1 62 Figure 3.24 end at about to come an 8.5–9.5 cm. ments settle the construction, end of the the after 5 years About process. tion consolida due to the rate decreased settlement the construction, end of the ( settlements about 60% are final of the structure surface. below the level about is groundwater 5–6 m The Limestone. Frankfurt follows the of 67 m adepth At surface below the limestone. clay and to semisolid layers of stiff of alternating consists which Clay, Frankfurt tertiary the begins surface, below the of aboutdepth 7 m gravel.and Ata sands and quaternary fillings are surface the At Main. am in shown is view ground The surface. below the 7 m is depth foundation The a spread foundation.

The measured settlements at the end of the construction of the super of the construction end of at the the settlements measured The for Frankfurt representative are conditions groundwater and soil The Foundation Systems for High-Rise Structures High-Rise for Systems Foundation

01 of Zürich Assurance Zürich of buildingHigh-rise complex

Ground view of the high-rise building complex of Zürich Assurance. Zürich of complex building high-rise the of view Ground 02

0 Me a Züric Complex ofth

ssurance II tro tunnel tro Figure 3.24 h underg Annex buildingan 50 m e round parking . d as Zürich Complex ofth surance II Figure 3.25 e ). After the the ). After N - - - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 [ construction the after two years until have kept open been upper floors the in joints several soil, of behavior the settlement long-term to the Due settlements. occurring the jacks balance hydraulic The cells. concrete stiff the and construction steel flexible the between installed jacks have been Hydraulic stiffness. a comparatively high with cells reinforcedconcrete with above storeys 23rd constructed were floor the The settlements. differential the and settlements the by 23rd tofloor,damaged the notwas third the from reaches which structure, steel flexible The cores. reinforcedconcrete the finishing after were closed joints expansion The superstructure. the and elements foundation the between were arranged joints expansion ments, ( foundations sublevels on single were founded annex The building. rise 5 kN/m 650 of pressures contact by comparatively high caused cm, 30 than greater [ Main am Frankfurt Assurance. Zürich of the complex building high-rise to the similar are conditions groundwater and The soil Hotel. Marriott the is part up 23rd to floor. the theAbove office tower office an is building sublevels. The three has basement The system. ( to 1972 1974 from wasconstructed Germany, Main, am Frankfurt in Senckenberganlage) (former name: Westend building Gate high-rise The 3.4.2 of 177 m aheight with [ Opernturm, now place the its is In structed. Figure 3.25 47 iue 3.27 Figure iue 3.26 Figure Westend Gate is the high-rise building with the biggest settlements in in settlements biggest the with building high-rise the Westend is Gate complex wasdecon building high-rise the 2002 and 2001 years the In , 48 ].

Westend Gate

Measured settlements. 2 . The raft foundations were only arranged under the high- the under arranged were only foundations raft . The ). ). It is 159 m high and is founded on a spread foundation on aspread foundation founded is and mhigh ). 159 is It For controlling the settlements and the differential settle differential the and settlements the For controlling 10.0 Measured settlements (cm) 8.0 6.0 4.0 2.0 0.0 0.0 47 ]. The measured settlements of the building were building of the settlements measured ]. The 1.0 Completion ofsu 2.0 Ye ars (a) pe 3.0 rstr ucture Zürichho Zürichhochhaus 4.0 Spread foundations Spread chhaus II I 5.0 45 ,

46 63 ]. - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 64 rise building, the water in the cushions was replaced by mortar. wasreplaced cushions the water in the building, rise high- of adjustment the the and construction end of the the After occurred. settlements differential small only so were regulated cushions the inside water.with The pressures initially were filled cushions The installation. the before waschecked cushions pressure of the tightness The of 3 mm. ness of 5 m have asize cushions ( raft foundation the under northwest Zürich Assurance. complex of the building high-rise to the similar are conditions groundwater and soil The level 14 m is foundation surface. the The of under 3.5 m. deep average an thickness with raft on afoundation TowerSilver constructed is 1975 from to 1978 ( wasconstructed and high 166 m is Germany, Main, am Tower Silver Frankfurt The in Bank) (formerly Dresdner 3.4.3 Figure 3.26

Due to the eccentric loading, 22 pressure cushions were installed in the the in were installed cushions pressure 22 loading, eccentric to the Due Foundation Systems for High-Rise Structures High-Rise for Systems Foundation

Silver TowerSilver

Westend Gate. × 5 m and consist of soft rubber with athick with rubber of soft consist and 5 m iue 3.29 Figure ) [ 42 , 49 Figure 3.28 ]. The pressure pressure ]. The ). The ). The - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 Figure 3.27 3 1 Retaining wal the found Constr Ju ( Installation oftheflo remaining g Ab Oct. l. 1974) sorption st

R unning jointbackfill Construction phases. 1973toMa uction oftheex ation (No l able ore s (Ma y andconst r. 1974) v. 1972to or slabsoftheoffic r. ca jack Hy 1974t va stor Ab ed drauli tion pitand s Ru sorption ru Fe ey o nning joint ction of b. 1973) c th e e join Constr of thegable Hy draulic jac t uction ks 4 2 Ga ( Fi Ju nishing ofconstr ble 4 ga Wo ( Base Fe l. 1974to bles ( b. 1973to rk ment fl s atthecentralcoreandth Ju l. 1973to Dec. oo Ju Spread foundations Spread rs totheg 1974) l. 1973) uction Constr Central core Oct . 1973) round le uction joint Ga ve ble 2 e l Ga join p with t bar

65 Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 66 Figure 3.29 Figure 3.28

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation

Hydraulic devices to adjust the settlements. the adjust to devices Hydraulic Silver Tower (the left building; on the right: high-rise building Skyper). building high-rise right: the on building; Tower left Silver (the Pressure cushionh Bo re d pilewall ∼ 7.0 m ∼ = 0.4m 5.0 m Retaining wall Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 tion time was due to a lack of investment during the oil crisis. The soil and and soil The crisis. oil the during wasdue to of alack investment time tion long 1973 construc from to 1980. The wasconstructed It south. the from surface. below the about 12.5 m level is foundation The raft. foundation thick on 3.5 m founded is which Germany, Main, am Frankfurt in building high-rise a142 m is FBC The 3.4.4 Figure 3.30 adjacent the and building high-rise the between settlements differential The settlements. were about 70% final of the settlements the ended, struction [ building high-rise of the corearea the in ( for 5 years Zürich Assurance. complex of the building high-rise to the similar are conditions groundwater From the beginning of the construction, the settlements were measured were measured settlements the construction, of the From beginning the

Frankfurt Bureau Centre (FBC) Centre Bureau Frankfurt

Frankfurt Bureau Centre (FBC). Centre Bureau Frankfurt Figure 3.31 ). The maximum final settlement was about 28 cm was about28 cm settlement final maximum ). The Figure 3.30 42 shows the high-rise building building high-rise shows the ]. About 1.5 years after con after ]. 1.5 years About Spread foundations Spread

67 - - Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 68 Figure 3.32 Figure 3.31

142 m Foundation Systems for High-Rise Structures High-Rise for Systems Foundation

Measured settlements. Cross section of the structure and measured settlements. measured and structure the of section Cross Fr ankf Settlements (%)Load (kN/m2) 200 400 100 ur 90 80 70 60 50 40 30 20 10 0 0 t Cl 0.0 ay Ma Ju Nov 1973 Ja l 1973 n 1975 y 1974 1.0 End ofconstr 2.0 Ye ars (a) 22 m

uctio 1:270 3. n 04 J J Ju un 1976 un 1975 24 m 36 m l 1973 .0

1:850 5. 20 cm 0 30 m 10 30 20

Settlement (cm) Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 The twin towers of the Deutsche Bank in Frankfurt am Main, Germany, Germany, Main, am Frankfurt in Bank towers Deutsche of the twin The 3.4.5 about is 1:1350 building [ high-rise ( 20 cm and 9.5 cm between are buildings Figure 3.33 jacks wasabouthydraulic ( jacks were hydraulic installed adjacent towers on the buildings, twin the of influence the To minimize settlements. of the isolines shows the Assurance. Zürich of the complex building high-rise to the similar are conditions groundwater and [ level about is foundation 13 m surface belowof The the 4 m. of 80 m asize with raft on afoundation towers are 1979 from to 1984 ( 158 mare were constructed and high Figure 3.35 The measured settlements are between 10 cm and 22 cm. and 10 cm between are settlements measured The

Twin Bank Deutsche of towers

Twin Towers of Deutsche Bank. Twin Towers Deutsche of ). The possible regulation of the differential settlements by the by the settlements differential of the regulation possible ). The ± 8 cm. 50 ]. Figure 3.32 × 60 m and a thickness 60 m athickness and Spread foundations Spread ). The tilting of the of the tilting ). The Figure 3.33 Figure 3.34 51 ]. The soil soil ]. The ). The ). The

69

Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4 70 REFERENCES Figure 3.35 Figure 3.34

1 2 3 4 . . . .

Foundation Systems for High-Rise Structures High-Rise for Systems Foundation für die Standardisierung des Oberbaus von Verkehrsflächen (RStO 12). (RStO von Verkehrsflächen Oberbaus des Standardisierung die für (2012): Richtlinie Stadtentwicklung Verkehr, und Bau für Bundesministerium im Straßenbau (ZTV E-StB 09). E-StB (ZTV Straßenbau im Erdarbeiten für Richtlinien und Vertragsbedingungen Technische Zusätzliche (2009): Stadtentwicklung Verkehr, und Bau für Bundesministerium Deutsches Institut für Normung e.V. (2001): DIN EN ISO 13793 Thermal e.V. 13793 Normung ISO Thermal für EN (2001): DIN Institut Deutsches Heave. Beuth Verlag, Berlin. Beuth Heave. to Avoid Frost of Foundations Design Thermal of Buildings: Performance Berlin. Verlag, Beuth (WU-Richtlinie). Beton aus Bauwerke Wasserundurchlässige e.V. Stahlbeton (2003): DAfStb-Richtlinie für Ausschuss Deutscher

Cross-section of the superstructure with hydraulic jacks. hydraulic with superstructure the of Cross-section Measured settlements. T ower 1 To wer 19 22 4 mthickra 18 16 14 16 14 10 ft A 12.8 m djacent buildin 12 0 T

ower 2 jack Hy N g draulic s 50 m ± 0.0 m Downloaded By: 10.3.98.104 At: 18:43 27 Sep 2021; For: 9781315368870, chapter3, 10.1201/9781315368870-4

14 10 11 12 13 15 16 17 19 18 21 20 22 23 5 6 7 8 9 ......

Berlin. Verlag, Beuth Beton. aus Bauwerke Wasserundurchlässige DAfStb-Richtlinie zur e.V. 555 Heft Erläuterungen Stahlbeton (2006): für Ausschuss Deutscher Auflage, Verlag Bau + Technik, Düsseldorf, Germany. Düsseldorf, Bau + Technik, Verlag Auflage, sicher. 10. und (2013): K. einfach Wannen Weiße Ebeling, G.; Lohmeyer, genutzten Deckenflächen. 2. Auflage, Ernst & Sohn Verlag, Berlin. SohnVerlag, & Ernst Auflage, 2. Deckenflächen. genutzten auf und Gründungsbereich im (2003): Abdichtungen K.-F. Emig, A.; Haack, Geotechnical design: Part 1: General rules. Beuth Verlag, Berlin. Beuth rules. 1: General Part design: Geotechnical e.V. Normung 7: für 1997-1 (2014): EN Eurocode Institut DIN Deutsches Part 1: General Rules. Beuth Verlag, Berlin. Beuth Rules. 1: General Part Design– 7: Geotechnical Parameters—Eurocode Determined Nationally Annex: e.V. Normung National 1997-1/NA für EN (2010): DIN Institut Deutsches EN 1997-1. Verlag, Berlin. EN Beuth to DIN Rules Foundations—Supplementary and of Earthworks Safety of the e.V. Normung Verification für 1054 (2010): Subsoil: DIN Institut Deutsches EN 1997-1:2010; Amendment A1:2012. Beuth Verlag, Berlin. Beuth A1:2012. 1997-1:2010;EN Amendment to DIN rules Foundations—Supplementary and of Earthworks Safety of the e.V. Normung Verification für 1054 (2012): Subsoil: DIN Institut Deutsches Verlag, Berlin. Verlag, Beuth Structures. of Retaining Stability Overall and Failure Embankment of Calculation e.V. Soil: Normung 4084 für DIN (2009): Institut Deutsches Verlag, Berlin. Verlag, Beuth of calculation. 1: Examples Stability—Supplement Overall of the e.V. Calculation Normung Ground: für 4084 (2012): DIN Institut Deutsches Berlin. (2000): A. Hettler, Berlin. Verlag, Beuth Analysis. Foundations, Raft Under Distribution Pressure e.V. Normung für (1974): Contact 4018 Institut Subsoil: DIN Deutsches Explanations and Examples of Analysis. Beuth Verlag, Berlin. Beuth of Analysis. Examples and Explanations Foundations; Raft Under Distribution Pressure of Contact Analysis Subsoil: e.V. Normung für (1981): 4018 1 Institut Supplement DIN Deutsches et du Mouvement des Solides Élastiques. Gauthier-Villard, Paris, France. Paris, Gauthier-Villard, Élastiques. Solides des Mouvement et du l’Équilibre de àl’Étude Potentials (1885): des M.J. Application Boussinesq, Ernst & Sohn Verlag, Berlin. &Sohn Ernst Berlin. (1959):Kany, M. Wirtschaftlichkeit und Organisation Technik, Bauingenieure: für Handbuch Interaktion. (2012): C. Moormann, K.; Zilch, R.; Katzenbach, Engineering, 2–7 December, Lima, Peru, 109–140. Peru, Lima, December, 2–7 Engineering, Foundation and Mechanics Soil on Conference Panamerican 6th dations. foun and interaction Soil–structure report: (1979): G.G. General Meyerhof, (1974):Kany, M. Verlag, Berlin, 1–8. Berlin, Verlag, isotropem elastisch- auf Platten starre belastete (1943): ausmittig H. Über Borowicka, Auflage P. (2003): Amann, Huder, J.; H.J.; Lang, , Springer Verlag, Berlin. , Springer

Untergrund. Untergrund. Berechnung von Flächengründungen von Berechnung Berechnung von Flächengründungen, Band 2, 2 2, Band Flächengründungen, von Berechnung . Springer Verlag, Heidelberg, Germany, 1471–1490. Germany, Verlag, Heidelberg, . Springer Gründung von Hochbauten von Gründung Ingenieur-Archiv Bodenmechanik und Grundbau. 7. Grundbau. und Bodenmechanik , XIV. Band, Heft 1, Springer 1, Springer Heft Band, , XIV. . Ernst & Sohn Verlag, & Sohn . Ernst Spread foundations Spread . Ernst & Sohn Verlag, &Sohn . Ernst Baugrund-Tragwerk- . Auflage

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