Technical Analysis and Monitoring of Rock Mass Behavior During the Provisional Support Phase of the Texanna Twin-Tube Tunnel in Jijel Province, Algeria

ISSN 2456-8066 International Journal of Advanced Engineering and Management Vol. 4, No. 1, pp. 16-28, 2019

Technical Analysis and Monitoring of Rock Mass Behavior During The Provisional Support Phase of The Texanna Twin-Tube Tunnel In Jijel Province, Algeria

Houssam Khelalfa

School of Civil Engineering and Surveying: Faculty of Technology, University of Portsmouth , UK. (Also affiliated to Department of Civil, Geotechnical & Coastal Engineering of K.E.C Laboratory, and Civil Engineering and Environment Laboratory (LGCE) of University of Jijel, Algeria)

ABSTRACT km. The tunnel is located in the project route In this research work, Rock Mass Rating (RMR) between KP: 24 + 818.545 - KP: 26 + 648.352 was used for the characterisation of rock mass for the right tube and between KP: 0 + 711.683 - KP: 2 + 593.879 for the left tube. along the tunnel alignment based on physical, geological and geotechnical data of the project area. The support systems were recommended for all geotechnical units using RMR and tunneling quality index (Q-system) support chart. Furthermore, Various design input parameters such as physical and geotechnical properties, in situ stresses, modulus of deformation of rock mass, support systems recommended by RMR were used as input parameters in Phase2 2D 8.0 software, in order to compare the calculation results with in-situ monitoring using Amberg Tunnel 2.0 software, to validate the numerical models and to check the deformations of the tunnel in the temporary support stage. Keywords: Tunnel, Rock Mass Classification, Provisional support, Deformations, Numerical modeling.

I. INTRODUCTION The Texanna twin-tube tunnel with 1.80 -km long (Fig. 1), was built as a road tunnel using the New Austrian Method (NATM) assuming that the Fig. 1 Photography and Geological cross section excavation technique used is drilling-blasting and and longitudinal profile of the south portal of the / or mechanical excavation, in anticipation of tunnel. heavy traffic in the framework of the project 'Penetrating Highway connecting Djen Djen Port The rock mass classification was carried out using to the East-West Highway', in a project of 110 rock mass rating (RMR) based on geology of

Houssam Khelalfa, “Technical Analysis and Monitoring of Rock Mass Behavior During The Provisional Support Phase of The Texanna Twin-Tube Tunnel In Jijel Province, Algeria,” International Journal of Advanced Engineering and Management, Vol. 4, No. 1, pp. 16-28, 2019

ISSN 2456-8066 International Journal of Advanced Engineering and Management Vol. 4, No. 1, pp. 16-28, 2019

project area, bore holes data and physical and hills, still well known, or dominate, under the strength properties of rock samples collected from neogene post-nappes, the Numidian series and the site. In the present work, the rock mass rating Mauritanian flysch of Guerrouch (formerly (RMR) were used as empirical methods for Texanna), to the south of the port of Jijel, on the characterization of rock mass based on real-time geological and site geotechnical data and physical northern edge of Tamesguida mapped by F. and strength properties of rock samples collected Ehrmann 1946. This author was noted in the from the alignment of tunnel. The rock mass valley of the DjenDjen wadi, the existence of along the tunnel axis was classified into Five "green rocks" presented as an ophiolitic complex geotechnical units (class III, III-A, IV, IV-A, IV- with intercalations of cornea and glandular gneiss. B). The support systems for each geotechnical In 1956, Mr. Durand Delga presents a precise unit were designed. The rock mass behavior in cartography to the sector of Texenna. The term of the in situ monitoring of total deformations and effects of provisional support metamorphosed "green rocks" are interpreted as a on (arch, bolts and shotcrete) due to excavation of lacolith in the micaschists of the Kabylian the tunnel profile were investigated and analyzed pedestal, which is widely carried southward; by comparing with simulated model (Phase2- 2D conception that complete and corrected by s) Bouillin in 1971 [11]. It then defines the unit of " The empirical and numerical design approaches Sendouah-Tabellout" which stratigraphically are considered very important in the viable and comprises from bottom to top the following efficient design of support systems, stability analysis for tunnel, and underground excavations layers: [1]. During stages of excavation projects, the - Green rocks probably containing pillow lavas, empirical methods like rock mass classification which may represent an ophiolitic complex; systems are considered to be used for solving - Shales and limestones attributed to the engineering problems [2,3]. The empirical Neocomian Jurassic; methods used defined input parameters in - Cretaceous flysch, schisto-sandstone for the designing of any underground structures, most part; this unit is overturned and recommendation of support systems, and metamorphosed, it is straddled by the Kabylian determination of input parameters for numerical pedestal to the north, and faces, to the south, modeling [4]. The empirical methods classified according to a very corrected contact, other series the rock mass quantitatively into different classes of flyschs carried on the Tellian domain. having similar characteristics for easily understanding and construction of underground A. Geological conditions along the tunnel engineering structures [5]. Numerical modeling is The alignment is not located in different gaining more attention in the field of civil and lithological units as previously indicated but in an rock engineering for prediction of rock mass old Albo-Alpien Flysch composed entirely of the response to various excavation activities [6]. alternation of mudstone and sandstone. The flysch Modeling of rock mass is a very difficult job due is composed of a mudstone with a folded, weakly- to the presence of discontinuities, anisotropic, moderately decomposed, weakly-weak, and fine- heterogeneous, and non-elastic nature of rock grained sandstone character that has a medium- mass, using empirical and numerical methods [7]. thick, poorly decomposed, moderately solid-solid The complex nature and different formation make rock nature. The first part of 10 m on the surface the rock masses a difficult material for empirical of the flysch unit is very or totally decomposed and numerical modeling [8]. It is suggested that and has a very low-excessively low rock nature. numerical and empirical methods be used together However, this zone of decomposition does not for the safe, stable and efficient design of tunnels, reach the tunnel dimension and according to other underground structures in the rock mass sounding studies, an alternation of mudstone and environment [9,10] and reliable support systems. sandstone which includes a nature of weakly II. GEOLOGY OF PROJECT AREA decomposed rock, partly weak, generally Between the mass of Babors, developed in the medium-solid will be observed at the tunnel level. west and that of the Kabylian pedestal, which The different geological conditions of rock mass extends eastward over more than 100 PK (Petite along the alignment of tunnel are shown in Fig. 2. Kabylie), there is a region of ridges and wooded

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Fig. 2 Geology and cross-sectional view of tunnel alignment of this study.

The geological conditions of the Texanna Tunnel characterized by average class II-a seismicity, site are composed by the Mauritanian Flysch, according to the RPOA, 2008 (Algerian which consists essentially of shale-sandstone standard). In the case of well-built tunnels alternations with hard quartzite passages, resting through a host rock of good quality, the seismicity on the surface of fractured and weathered shales. effects are generally low. However, special All of these formations cover the formation of attention should be given to areas with a host rock hard argillite slightly weathered and fractured of poor quality, particularly at tunnel portal, whose upper part, and in depth it is very hard and where the coverage is lower and there is generally little fractured. This argillite is present almost all lower quality land. Under these conditions, along the tunnel as shown in Fig. 3. special precautions must be taken in the design Based on the foregoing considerations, it appears and construction phase to counter the seismic that the study area is located in an area effects on the tunnel structure.

Fig. 4 Photography of tunnel alignment Geology of this study.

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III. ROCK MASS CLASSIFICATION The value of this system may be different for ALONG THE ALIGNMENT OF THE undisturbed and disturbed rock [16]. TUNNEL A. RMR- system Table 1. Geotechnical Design Parameters and The empirical methods classify the rock masses Rock mass classification for twin tube tunnel. into different categories having less or more Between the Between the similar geological and geotechnical properties KP part: 26 exit gate on the basis of results obtained from rock mass + 230 - KP: part- KP: 26 26 + 550 of characterization. The rock mass classification + 550 of the the right systems are considered very beneficial to use right tube Kilometric point (P.K) tube and KP: and exit gate during the initial stages of the project when 2 + 191.682 - KP 2 + limited information about rock mass behavior, - KP: 2 + 490.970 of 490.970 of stresses and hydrological characteristics are the left tube the left tube available [12, 13]. The rock mass along the of the tunnel of the tunnel tunnel axis were classified into different categories based on Geo-mechanical Low Rock Middle Rock Rock class type classification system also called Rock mass (IV) (III) rating (RMR- system) [4]. This system utilised The level of the tunnel is the following six parameters for rock mass located entirely in the flysch classification based on quality in to various consisting of the alternation Geological determination groups of similar behaviours: of mudstone and sandstone of - Uni-axial Compressive strength (UCS); the old albo- Alpien. - Rock Quality designation index (RQD); - Spacing of discontinuities (DS); Underground water State of groundwater in the - Condition of discontinuity (DC); condition form of dripping and leaking - Ground water condition (GWC); UCS, Uniaxial - Orientation of discontinuities (DO). compressive strength 10,0 13,0 (MPa) Various physical and geotechnical properties of GSI, Geological strength 25 40 rock mass along the tunnel alignment were Index determined by testing the rock samples obtained mi, Material Constant 10 10 along the tunnel alignment. The different D, Disturbance factor 0 0 – 0,8 physical and Mechanical properties of rock Ei, Elasticity Modulus 6,75 15,0 mass along the tunnel length are presented in (GPa) Table 1. B. Q- system υ, Poisson’s ratio 0.34 0.32 The Rock mass classification systems are considered as an integral part of the designing of γn, Unit weight (kN/m3) 27 27 underground structure, support systems, stability H, Effective Rock Height 60 130 analysis and in determination of input (m) parameters for numerical modeling within the c, Cohesion D=0 345 139 rock mass environment [14]. Various rock mass (kPa) D=0.8 199 classification system has been developed based Ø, Internal D=0 33 friction 32 on civil and mining engineering case studies by D=0.8 22 different researchers. In this research, RMR and angle (º) Nicholson Q systems were used due to its flexibility in Em, & 0,49 2,2 terms of input parameters and widespread range Deformation Bieniawski modulus for selection of support systems. The Q-system Hoek & D=0 2,4 (GPa) 0,4 is developed by Bortan in 1974 at Norwegian Diederichs D=0.8 0,77 Geotechnical Institute (NGI) [15]. The Q- RMR, Rock Mass Rating 32 44 system has wide applications in underground Q, Tunneling Quality 0,55 1,1 excavations and field mapping, and it depends Index on the underground opening and its geometry.

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This system classifies the rock mass moment. If the support is applied without environment into different classes on the basis allowing any deformation, the support system of: will be overloaded and will no longer be - the rock quality designation (RQD), economical. And if not, deterioration of soil and - joint number (Jn), excessive deformation will occur. - joint roughness number (Jr), - joint alteration (Ja), Table 2 Provisional Support Systems Offered in - joint water reduction factor (Jw), Twin-tube Tunnel under the Massif Rocky - and stress reduction factor (SRF). Classification System and The values of this system indicate the quality of recommendation. rock mass and give description about the Low Rock Middle Rock Rock class type stability of an excavation within the rock mass (IV) (III) environment. The maximum value of Q-system R, Tunnel radius (m) 7.5 7.5 indicates good quality of rock meaning good P0, In-situ pressure (MPa) 1.62 3.51 ESR, Excavation Support 0.9 - 1.1 0.9 - 1.1 stability and the minimum value indicates poor Ratio quality of rock meaning poor stability [17, 18]. Sfr+B, Support class The RMR and Q classification systems were (Grimstad and Barton 1993, 6 6 applied on bore hole data and physical and Barton 1995 & 2002) strength properties determined in laboratory of k=0.25+7Eh(0.001+1/z) 0.30 0.39 advance of the collected rock samples along tunnel advance of the the upper alignment. Based on the results obtained from Advance upper half by Calotte half by 20 Excava ment 35 to 50 m RMR and Q system, the rock mass along the to 25 m tion / of the maximum tunnel axis was divided into five geotechnical maximum Provisi upper advanceme units. The results of RMR and Q classification onal half / advancement nt of the system are presented in Table 1 and 2. support lower of the lower Strauss lower half half. half of 3.0 m IV. PROVISIONAL SUPPORT SYSTEM of 2.0 m maximum The fundamental principle of digging a tunnel maximum with the new Austrian method is to transport the Dimen sion HEB 220 HEB 180 rock by itself (the ability to transform a mass of Steel Steel (mm) retaini rock that surrounds the profile of a tunnel into a S275JR Dista ng load-carrying element instead of an element that nce 0.75 1.25 - 1.50 constitutes a load). Allowing the rock to deform (m) Shotcr RN- slightly (provided that it remains within the (cm) 35 25 permissible safety limits) considerably reduces ete 30/40 ( 2x ( 2x the loads on the bearing system. The rock Steel Steel Q589/443) (mm) Q221/221) released under control transfers the load to the lattice FeE400 (150x150x (150x150x6.5) sides and thus uses its transport capacity to the 6.5) Anchor Steel maximum by forming a transport chain around (mm) 200/200/15 200/200/15 the excavation. Instead of carrying all the load plate FeE26 if Dimen Drain of the rock, the support systems are rather used necessar sion 3x 12 / pipes to control the plastic deformations while y (m) preserving the integrity of the transport chain Injecti around the excavation and to avoid the on Pre- t=3mm 45x (Ø 7.0, 45x (Ø 5.0, excessive relaxations. So the flexibility of the support ST37 a=30c L= 8m) L= 6m) system to the point of adapting to the ing m deformations of the rock is one of the most iron important criteria of the method. If the rock is bar Len L= Steel / Length too weak to carry its own load, the support used SN, Ø gth 6m FeE400 stabilizes the system by providing additional 32 mm 19 - (PG No. / No. pressure still needed to reach equilibrium after Rock 23 PULT = bolt Len L= approaching the rock carrying capacity. As a 250 KN IBO, Lenght / gth 8m result, limited deformation is allowed before and in St III Ø 32 29 steel) mm No. No. / after the application of the primary support -33 system (provisional). The main feature of Déformation mesurèrent Will be performed every 10 NATM is the application support at the exact (mm) meters along the tunnel

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The elements of the provisional support system consist of the following systems and / or their various combinations depending on the class of rock or geological conditions encountered. A. Shotcrete The use of shotcrete is essential as a supporting element that prevents the relaxation of the peripheral rock. Shotcrete is the element that provides the greatest support pressure among the support elements. A first-layer shotcrete will be applied in all support systems after excavation against the risk of failure and collapse of the layers. A second layer shotcrete will be applied in all support systems after the location of Steel lattice and steel Retaining (Fig. 4).

Fig. 4 Photography of tunnel shotcrete stage.

B. Steel lattice A steel lattice will be applied between the Fig. 5 Photography of tunnel Steel lattice stage. concrete layers to form the static and constructive reinforcement of the concrete coating. The use of steel lattice is intended to ensure adhesion between rock and shotcrete, stabilization, increase in shear strength and prevention of excessive cracks until the setting of concrete (Fig. 5). C. Steel retaining In principle, the steel support provides immediate support before the shotcrete freshly begins to wear and constitutes the reinforcement with the lattice after the concrete has acquired its strength. Steel support is also a support for drilled bolts and provides mental confidence for employees. HEB "180, 220" profiles are used in this project (Fig. 6). Fig 6. Photography of tunnel Steel retaining stage.

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D. The pipes or pre-supporting iron bar: underground excavation, providing support with The purpose of the piles support is to provide bolts, steel retaining, steel lattice and shotcrete. support by Umbrella effect around the forehead. In addition, the load split between the For this purpose perforated pre- support will be excavation phases and the material softening used with Ø 5.0 "and 7.0" injection pipes can be applied to the model. The designation of depending on the rock classes. Their distance is support systems based on practice and between 20-40 cm, depending on the class of experience, numerical analyzes were considered rock. In addition, after attaching certain pipes to as a guide for practical decisions. The support the hole, making them wait without an injection system will have to be revised according to the for a moment ensures the drainage of the actual field situation and the geological mapping groundwater that can come on the face. In the and the footage results. following by the injection these pipes will assume their own function (Fig. 7).

Fig. 7 Photography of tunnel pre-supporting iron bar (Umbrella) stage.

E. Rock bolts: Rock bolts will be applied systematically as part of the support type system. Rock bolts are used in all support systems because they increase the quality and strength of the rock mass by Fig. 8 Photography of tunnel Rock bolts stage. increasing shear strength, reducing deformation in the tunnel and preventing rock breakage. The whole procedure will be performed by injection A. Soil and provisional support modeling: given that it is not a design that aims to support The calculation sections are taken on the part the rock blocks or thin layers. The length of the represented by the rock formation between the rock bolts is chosen so that they extend at least determined KP (kelometric point). The ~ 2 m above the plastic zone formed around the calculations for these sections are valid for the tunnel. The diameter of the injection hole will part represented by the section. The parameters be 1.5 of the diameter of the bolt. The bolts will of the rock mass are estimated with these be installed in radial position on the walls of the calculation sections according to the tunnel. Bolts of type SN and IBO will be used recommendations and approaches of the (Fig. 8). literature. Excavation coordinates are given in V. NUMERICAL MODELING AND the X-Y system that accepts the center of the ANALYZES PERFORMED WITH THE tunnel in the zero coordinate (O1). These units PHASE 2 2D SOFTWARE are given in meters in the program. The numerical analyzes were performed with Relevant soil modeling is very difficult in soil the Phase 2 2D program (Version 8.0). Is a finite excavations given the many uncertainties and element program developed by the University of complexity. The numerical analyzes are Toronto which models the masses of rock and performed according to the elastic-plastic the sustained behaviors of these masses. The solution. Thus the detailed modeling which program is progressively modeling the

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includes all the conditions is neither possible nor A. Evaluation of the deformations of the this modeling is useful. The relaxation of middle rock class (III) of the part material used in the weak rock masses as between KP: 26 + 230 - KP: 26 + 550 indicated above is applied at 0.65 (65%) in the of the right tube and KP: 2 + 191 - KP: excavation of the upper half and 0.35 (35%) is 2 + 490 of the left tube of the tunnel: reflected in the model with the installation of the Examination of displacement formed around supports of the upper half and when excavating the tunnel (Fig 9) indicates a displacement of 3.25 cm in the ceiling (summit), 2.75 cm and the lower half. The purpose of this distribution 2.50 cm in the left and right wings of the tunnel, is to determine the rate of load to be carried by 0.75 cm and 1.25 cm in the lower left and right the rock and the rate of load to bear by the parts of the tunnel and 4 cm in the bottom of left supports. The linear composite is applied in 3 tunnel tube. In the right tunnel tube, is observed layers on the model in the excavations of the a displacement of 2.5 cm in the tunnel ceiling, upper part, the lower part and the slab. In the 1.75 cm and 2.0 cm in the left and right wings, 1.50 cm and 1.75 cm in the left and right lower excavation levels, the first layer of shotcrete halves and 4.25 on the bottom. When the lining and the steel retaining (HEB) and the earthquake was applied the examination of the second layer of shotcrete liner and steel lattice deformations around the tunnel (Fig 10) shows are entered into the model. The analyzes are in the left tunnel tube, a displacement of 1.2 cm carried out in two stages namely, for earthquake in the tunnel ceiling, 0.6 cm and 0.2 cm in the and without earthquake. Simplification of the left and right wings, 0.8 cm and 1.0 cm in the model may be possible under the following left and right lower halves and 1.4 on the bottom. In the right tunnel tube, a displacement conditions: of 0.8 cm in the ceiling of the tunnel, 0.6 cm and - Reduction of three-dimensional conditions to 0.2 cm in the left and right wings, 1.0 cm in the two dimensions, left and right lower halves and 1.6 on the - Acceptance of the symmetry of the section bottom. According to the results, it appears that with the axis, the provisional support system consisting of - Simplification of the soil with simple steel lattice, steel retaining, bolts and shotcrete descriptions, is able to carry the loads from the tunnel. Total displacement in Situation without earthquake in - Simple and comprehensive description of the class IV is shown in Fig. 10 and with earthquake progress conditions of the tunnel and the is shown in Fig. 11. excavation, - Soil is considered homogeneous and isotropic.

Fig. 9 Total displacement in Situation (without earthquake) in class IV.

REFERENCES

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Fig. 10 Total displacement in case of earthquake in class IV.

VI. MONITORING OF THE UNDERGROUND monitoring results are often affected by DEFORMATION instrumentation, installation and environmental Tunnel ground deformation monitoring is the effects. The type of instrumentation chosen must main means for selecting the appropriate ensure the following: methods of excavation and retaining from - A feasible installation procedure, among those provided in the design to ensure - Sustainability during the monitoring period, the safety of the tunnel construction (including - Protection against damage during construction, the safety of personnel in the tunnel and the - Simple processing of measurements safety of structures on the ground surface). The (acquisition and transmission of data), construction of the system is planned for the - Precision is required. continuation of the stop of the deformations and In general, close readings of excavation movements of the ground likely to occur after activities are taken daily; the frequency is the construction of the elements of primary reduced with the distance to the forehead and support in this system. In this case, it is accepted the decrease of the displacement rates. Shorter that there will be no load transfer on the coating monitoring intervals may be required due to the concrete as the pressure from the ground is specific project requirements. Monitoring supported by the provisional support system. As sections in tunnels and shafts are usually located a result, a separate analysis was not performed at distances of 5 to 20 m depending on the for the coating concrete. The monitoring conditions and requirements limits. A possible program includes the specification of the concept showing minimum reading frequencies measurement procedure, the location of the and ranges for surface and underground monitoring devices and the monitoring monitoring for a summit-wings-bottom schedule. Attention is given to the fact that sequence as shown in Fig 11.

Fig. 11 Photography of the tunnel underground monitoring.

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In general, there are types of failure that cannot - Observations in asymmetrical connection, be detected in time by deformations monitoring, - Measurements in a very dusty environment or it is recommended to use additional monitoring when there is a lot of vibration (i.e. Caused by of absolute displacements, but in a small extent. machines). Thus the presence of an emergency surveillance The surveyor must record and submit the system in case of adverse field conditions is following items after each measurement action: ensured. In the case of block rock mass tunnels, - Measurement sequence system (relative to the the characteristic hazards are the detachments measurement section or along the caused by the discontinuity of the blocks, tunnel), therefore the observations must concentrate on - Unmeasured points and reason indication the soil structure, the location and the (destroyed, not visible, etc.), orientation of the discontinuity with respect to - Significant displacements (measurement error, the alignment of the tunnel. In the case of rapid increase in displacements), tunnels with moderate to high overload in the - Readings to zero, bedrock or foliar mass, the characteristic risks - Monitoring conditions (air quality, vibration, are; the orientation of the stratification or limited visibility, sources of heat, etc.). foliation, the displacement of the pavement, the displacements of the soil and the structure of the The geometric definition of the sections is soil. consequently the Observation focused on; shown on the drawings. The purpose of these visual inspections, laboratory tests, absolute sections is to measure convergences in the displacement monitoring. tunnel during construction. In general, the convergence sections will be composed by 5 A. Monitoring methods and points distributed as shown above, one in the requirements: summit, two in the forward section (calotte), in Measurements are performed using a total the gables at a height of 1.50m from the base station and objectives. Precise prism lenses as excavation and the other two, at the stross well as bi-reflex lenses (reflectors) are used and section, at a height of 1.50m from the tunnel their spatial position in the global coordinate bottom, also in the gables. system or project is determined. Discrete three- dimensional displacement measurements are B. Deformations diagrams from performed by repeated measurements (usually monitoring results: on a daily basis). Since full monitoring cannot A lateral and longitudinal displacement of 40-55 usually be performed from one position, an mm / month has been observed in some sections interconnected observation pattern is required, of the middle rock (Class III) left tube calotte which is established using identical reference (Figure 13). Also in the right tube calotte, lateral points. Stable reference points are differentiated and longitudinal movements of 30-40 mm / 2 from points that always move. Points with a months (Figures 14) and lateral displacements defined maximum displacement rate (usually of 90 mm / 2 months (Figures 14a, c), which <1mm / month) can be used as reference points. forces us to reinforce immediately by bolts IBO / L = 8m (3 top, 2 wall right side, 2 wall left The principle of "free parking determined" is side), on the other hand, the remains sections are used to obtain the position of the instrument. stable. Consequently; deformations were The absolute position of all coordinate stopped and class III-A was created. In along components of the marked measuring points the low rock tunnel (Class IV) (Figures 15, 16); shall be determined with an accuracy of +/- 1 in the left tube; a maximum settlement of 80 to mm (standard deviation) with respect to 120 mm / 4 months was observed (Figure 15 a, adjacent measuring sections over the entire b, c), lateral and longitudinal displacements of observation period. The following sources of 40- 100 mm / year (Figures 15). In the right error should be avoided: tube; maximum deformations of 20 to 40 mm / 2 - Observations near the tunnel wall (minimum months have been observed (figure 16 a), wall distance of 0.5 m to 1 m), deformations up to 70 mm / 2 months (Figure 16 - Measurement errors due to refraction (for b), maximum settlements of 60 to 80 mm / year example. observation through or near heat (Figure 16c, d), deformations of 60-150 mm / 10 sources), months (Figures 16 e, f, g), which forces us to - Position of the instrument near the side walls, reinforce immediately by bolts IBO / L = 16m

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(6 top) and sometimes bolts IBO / L = 12m (2 construction tunneling phenomenon without lateral right, 2 lateral left), on the other hand, the making uncertainties between real and digital remains sections are stable. Consequently; data. In conclusion, maximum attention must be deformations were stopped and classes IV-A, given to deformations when the implementation IV-B were created. of tunnel digging and the setting up of Real deformations are more than numerical provisional support. Left tube Tunnel Cross modeling when we compare the monitoring section KP - 2,485.000 / First measure: results with numerical modeling results, we can 30.01.2018, Last measure: 21.03.2018 is shown say that it is logical, because the software cannot in Fig 12. really simulate at one hundred percent

(a) (b) Fig. 12 (a) Left tube Tunnel Cross section KP - 2,485.000 / First measure: 30.01.2018, Last measure: 21.03.2018, (b) Right tube Tunnel Cross section KP 26,527.000/ First measure: 17.01.2018, Last measure: 26.03.2018.

VII. CONCLUSION site engineers to evaluate the rock mass The characterization of the rock mass and the behavior and its effects on engineering site is very essential for tunnel design. Effective structures and support systems. This Method characterization provides reliable design input resolved complex engineering problem utilising parameters for classification systems. The Plane Strain Two Dimension (2D) Analysis, construction of any engineering structure in the Axisymmetric 2D Analysis and Three rock mass causes the redistribution of stresses in Dimension (3D) Analysis. situ which is not evaluated by empirical It is necessary to create a coating system methods, it evaluates only the quality of the rock (shotcrete, steel lattice, HEB and anchor bolts) mass. Therefore, it is very necessary to with able to operate with the environment and evaluate/predict the quality of rock mass and in able to provide bearing capacity immediately turn the "RMR- Q - systems" value with more after excavation in order to meet the precision. Moreover, the empirical methods do requirements, measure and evaluate not analyze either the performance of the continuously the deformations and surface support systems, the distribution of the movements inside the tunnel during excavation constraints around the opening and the activities. On the other hand, deformations deformation around the tunnel while it is used formed and possible structural damage must be for the determination of the input parameters for measured and monitored. Measurements made numerical methods. for this purpose; The are evaluated with the geomechanical conditions artificial intelligence used to deal with such and necessary modifications after the nonlinear relations problems of engineering and geotechnical measurements required in the it can also be used to confirm and improve the tunnel must be made and evaluated during design solutions in any engineering projects. construction to perform some revisions in the Numerical modeling in rock and civil support systems (thickness of shotcrete, coating engineering is used as a tool that facilitates the

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interval, bolt density etc.) and production Pakistan–a design parameters by the following recommendations: perspective. International Journal of Scientific Engineering and - Benefit the most of the natural resistance of the Technology, 3(10), 1292-1296. rock mass, to this end insert support systems at [3] Genis, M., Basarir, H., Ozarslan, A., Bilir, the most opportune moment, E., & Balaban, E. (2007). Engineering - Use flexible support systems that can geological appraisal of the rock masses and accommodate rock deformations and support to preliminary support design, Dorukhan ensure full contact between the support system Tunnel, Zonguldak, Turkey. Engineering and the excavation surface, geology, 92(1-2), 14-26. - Quickly avoid excessive relaxation of [4] Bieniawski, Z. T. (1993). Classification of deformities using provisional support, rock masses for engineering: the RMR - Control excavation and support systems with system and future trends. In Rock Testing permanent deformation footage, carry out a and Site Characterization (pp. 553-573). progressive excavation or move to other classes Pergamon. of support if necessary, [5] Bieniawski, Z. T. (1993). Classification of - Ensure the total functioning of the support rock masses for engineering: the RMR system, particularly in low rocks, system and future trends. In Rock Testing - Provide flexibility for rock classes and support and Site Characterization (pp. 553-573). systems specified based on observations and Pergamon. measurements made during excavation. [6] Vakili, A. (2016). An improved unified constitutive model for rock material and Acknowledgements: guidelines for its application in numerical This work was funded by the K.E.C Laboratory, modelling. Computers and Geotechnics, 80, Department of Civil, Geotechnical & Coastal 261-282. Engineering, under the project number (PN): [7] Jing, L. (2003). A review of techniques, KEC.LAB.DCGCE.T.PTTJA2017N004. advances and outstanding issues in numerical modelling for rock mechanics Funding: and rock engineering. International Journal This study was funded by K.E.C Laboratory of Rock Mechanics and Mining (grant number (PN): Sciences, 40(3), 283-353. KEC.LAB.DCGCE.T.PTTJA2017N004.): [8] Harrison, J. P., & Hudson, J. A. (2000). Laboratory, in-situ tests and monitoring are Iillustrative workable already done on the site, in Jijel province, examples. Engineering Rock Mechanics. Algeria. This work was funded and supported Part, 2. by the K.E.C Laboratory (People's Democratic [9] Gurocak, Z., Solanki, P., & Zaman, M. M. Republic of Algeria/ Ministry of Housing, (2007). Empirical and numerical analyses Urbanism and the City/ Decision approving of support requirements for a diversion Agreement N / 2016/243/686/02 for Mr. tunnel at the Boztepe dam site, eastern KHELALFA HOUSSAM), Department of Turkey. Engineering geology, 91(2-4), 194- Civil, Geotechnical & Coastal Engineering, 208. under the project number (PN): [10] Bobet, A. (2010). Numerical methods in KEC.LAB.DCGCE.T.PTTJA2017N004. geomechanics. The Arabian Journal for Science and Engineering, 35(1B), 27-48. [11] Djellit, H. (1987). Évolution tectono- EFERENCES R métamorphique du socle kabyle et polarité de mise en place des nappes de flysch en [1] Rasouli, M. (2009). Engineering geological Petite Kabylie occidentale studies of the diversion tunnel, focusing on (Algérie) (Doctoral dissertation, Paris 11). stabilization analysis and support design, [12] Hoek, E., Kaiser, P. K., & Bawden, W. F. Iran. Engineering Geology, 108(3-4), 208- (2000). Support of underground 224. excavations in hard rock. CRC Press. [2] Ali, W., Mohammad, N., & Tahir, M. [13] Hoek, E., & Brown, E. T. (1997). Practical (2014). Rock Mass Characterization for estimates of rock mass Diversion Tunnels at Diamer Basha Dam, strength. International journal of rock

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