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Research Article Volume 7 Issue No.4 Planning, Design and Estimation of a Check B.H. Ramathilagam1, S. Murugesan2, M. Manikandan3, A. Arumugaraja4, Assistant professor1, U. G. student2, 3, 4 Department of Civil Sethu institute of technology, Virudhunagar, India

Abstract To overcome these issues on a global scale, water is the most severe type of soil erosion. It occurs mostly in the form of running water. This study was to develop information from dam which check dam can be adopted for the purpose of ground water recharge. are constructions built across a or a and used to interrupt and store water for special purpose. Check dams are comparatively smaller and more temporary to other types of dams for the purpose of ground water recharge. The Study consisted of a site selection phase, a surveying phase, an planning phase, an design phase and estimation analysis. .This Particular scheme lies in highly favourable zone for recharge as classified in the zonation map for Ground water recharge. By implementing this scheme, with in the zone of influence of about 1 km radius from the check dam site will be benefitted by way of percolation. Increase the Ground water level and increase the revenue through the ayacut . Totally 185.02.0 Ha Ayacut is benefitted through Seventy Eight No’s of wells. Moreover, all the wells (both domestic and agricultural wells) within the zone of influence will be recharged. The length of the check dam is 106m. The design and Estimation of the structure is done using the software Ms-Excel. The total estimation amount of the project is Rs.248.57461 Lakhs.

Keywords : Ground Water-Recharge, Water , Check Dams, Flow Velocity.

I. INTRO DUCTION consider for selecting a site the water demand and ground water is necessity for cultivate crops and increase revenue and A dam is a barrier that impounds water or underground standard of living afterwards opinion from public and . created by dams not only suppress grievance should be noted. leveling should be done in the but also provide water for activities such as , human proposed site with the use of surveying instrument like auto- consumption, industrial use, aquaculture, and navigability. level, tripod, tape, plump bob, thread. Surveying work of Hydropower is often used in conjunction with dams to leveling is carried out from upstream to downstream of the generate electricity. A dam can also be used to collect water river up to 50 M from the site then reduced level of each or for storage of water which can be evenly distributed points should be calculated from height of collimation method. between locations. Site should be cleared from vegetable, leaves, un bushy level Dams generally serve the primary purpose of retaining after foundation should be erected at where the soil is week water, while other structures such as floodgates or leaves are depth up to 3m to 5 m . used to manage or prevent water flow in to specific land regions. There are several types of check dams; each type of dam is constructed with different conditions. In general, some essential considerations of check dams need to be considered. First, the site of each check dam must be carefully inspected to assess dam settling. The slope of waterway should be no more than 50% and the depth to bedrock should be over 2 feet (Department of Environmental Quality, 2005). Second, check dams materials will vary depending on conditions and locations. Logs and rock are usually utilized in permanent or semi-permanent check dams for their stability, and sandbag is for short term purpose (Mississippi Department of Environmental Quality, 2011) This type of dam project can be widely utilized in small open channels and drainage ways, including temporary and permanent swales. Check dams flattens the gradient of Figure 1 channels and blocks streams from fluently flowing. As a consequence, not only the velocity of flow is mitigated, but I. Plan of check dam also the path can be distributed toward vegetation . On another The planning of check dam done should be in two views hand, check dams also trap from streams which A) Half plan at top & half plan at foundation. b) cross -section helps to reduce water erosion. of check dam

II. S ITE S URVEYING A. Half plan at top & half plan at foundation Before starting surveying work to select the area where Half plan from top view and half plan at foundation are the check dam is constructed and some procedures should be shown in fig 2. From top view plan shows apron & of both U/S

International Journal of Engineering Science and Computing, April 2017 6464 http://ijesc.org/ side and D/S side. from left to right half top plan shows figure total through scour vents and over 2. U/S Return wall then us bed level +328.280 to crest = 17565.088cusecs +329.480 and stilling basin is 6.40m wide afterwards cement Design discharge for the anicut = 17497 cusecs concrete blocks in right side portion ends is apron in D/S bed level+328.280 and 8.00m wide. D. Stability calculation The stability of body wall of the anicut was checked for the following conditions:

1 empty without eq 2. Reservoir at MWL,with tail water with uplift 3.Reservoir at FRL, no tail water with uplift 4.Upstream side fully silted up to crest, No silt/water at D/s side WT @Crest

Figure:2 Half plan at top & half plan at foundation

B. Cross-section of check dam

Cross-section of check dam shows abutments, d/s wing at start ,u/s wing & return, d/s wing at end, d/s wing at basin. 1. Maximum stress= SV/b*(1+6e/b) = 3.5442T/m2 cement concrete 1:3:6 using 40mm aggregate m15 graded Minimum stress = SV/b*(1+6e/b) = 1.0501T/m2 aggregate with surface reinforcement details are shown in figure 3 2. Maximum stress= SV/b*(1+6e/b )=3.5442T/m2 Minimum stress = SV/b*(1+6e/b) =1.0501T/m2

3. Maximum stress= SV/b*(1+6e/b) =3.5442T/m2 Minimum stress = SV/b*(1+6e/b) =1.0501T/m2

4.Maximum stress= SV/b*(1+6e/b) =3.5442T/m2 Minimum stress = SV/b*(1+6e/b) =1.0501T/m2

E. Surface flow

Regime width = 4.83 sqrt (494.691) =107.5m

Looseness factor = Existing overall length /Regime width = 107.5 M

Scour depth = 3.6 M Stilling basin level = 327.780 m Figure 3 CROSS-SECTION Total horizontal floor length: II. DESIGN Length of u/s floor = 3.00m A. Design the check dam structure The check dam structure design in limit state method. Width of the body wall = 2.50m Design should be followed by the rules of indian standard IS 6966-1973. D/s floor length = 6.80m

B. Rear water calculation Total floor length required =12.30 m To find out the discharge in the rear water calculation by providing stilling basin length = 6.40m applying manning’s formula (i) area (A)=183.478m2 (ii) (p) =107.054 m (iii)discharge=17497 cusecs. Hence total floor length = 12.30m

C. Front maximum water level F. Downstream protection work

The front maximum water level determines discharge the Length of downstream protection block = 1.5 D amount of water from anicut and back water length calculation =5.7 m : P/ HO 0.65 < 1.33 (velocity of approach should be taken) total Hence provide 4 rows of CC block of size 1.5x1.5x0.9 m tk 3 discharge over the weir = 497.38m /sec of pitc hing (Is 6966-1973) = 850mm % of discharging passing = 100.39%

International Journal of Engineering Science and Computing, April 2017 6465 http://ijesc.org/ slope of =2.00:1

Length of launching =8.560 m qty of stone reqd for tk = 0.85x 8.56 = 7.276 m3

Inner tk reqd = 7.276/8 = 0.9095m

Quantity of pitching provided = 10.4 m3

Quantity of pitching required = 9.416 m3

G. Upstream wing wall &returns Maximum stress = P/A(1+6e/b) =161.724 KN/m2 pa=1/2*w*h2*ca =130.815 KN Minimum stress =P/A (1-6e/b) =5.145 KN/m2 earth pressure: Vertical component =94.163 KN J. Design of downstream wingwall at end portion Horizontal component =90.806 KN pa=1/2*w*h2*ca =130.815 KN

Earth pressure: Vertical component = 70.189 KN/m2

Horizontal component = 67.805 KN/m2

Maximum stress = P/A(1+6e/b) =184.963 KN/m2

Minimum stress =P/A (1-6e/b) =3.728 KN/m2

H . Design of downstream wing wall at start Maximum.stress = P/A(1+6e/b) =73.277 KN/m2 pa=1/2*w*h2*ca =130.815 KN Minimum stress =P/A (1-6e/b) =73.277KN/m2 earth pressure: Vertical component = 187.148 KN/M2 K. Design of downstream wingwall at return portion Horizontal component =90.806 KN/M2 pa=1/2*w*h2*ca =130.815 KN

earth pressure: Vertical component t= 70.189 KN/M

Horizontal component=67.805 KN/m2

Maximum stress = P/A(1+6e/b) =187.148 KN/m2

Minimum stress =P/A (1-6e/b) =2.468 KN/m2 2 I. Design of downstream wingwall at basin portion Maximum.stress = P/A(1+6e/b) =139.242 KN/m Minimum stress =P/A (1-6e/b) =7.309 KN/m2 pa=1/2*w*h2*ca =130.815 KN III.ESTIMATION Earth pressure: Vertical component = 91.676 KN/m2 The estimation of the total approximate cost of the project is calculated by the detailed estimated method are as in the below Horizontal component t=88.562 KN/m2 tabulation.

International Journal of Engineering Science and Computing, April 2017 6466 http://ijesc.org/ SI.NO Qty Description of work Rate Per Amount 1 L.S Clearing the site L.S 50000 2 560 m3 Earth work excavation for 123.50 m3 69160 foundation 3 3640 m3 Earth work excavation in all 55.60 m3 202384 soils except medium rock 4 4200 m3 Extra for every additional 6.90 m3 28980 lead of 10m 5 4200 m3 Extra for every additional 5.50 m3 23100 lift of 1m 6 C.C 1:4:8 using 40 mm Hard broken stone jelly A) 100 m3 Up to 1.50 m depth below 3716.96 m3 371696 G.L 7 C.C 1:3:6 using 40 mm hard broken stone jelly a) 1580 m3 Upto 1.50 m – 4.50 m depth 4084.16 m3 6452970 below G.L 8 Cement concrete 1:2:4 using 20mm metal a) 266 m3 Up to 1.5 m depth below 5179.46 m3 1377736 G.L b) 266 m3 From 1.5 m depth -4.5 m 5238.06 m3 471425 below G.L 9 Cement concrete 1:2:4 (Graded mix ) 60% of 40mm & 40% of 20mm a) 1580 m3 Upto 1.5 m depth below G.L 4991.00 m3 7885777 b) 266 m3 Upto 1.00m height above 4991.00 m3 1327605 G.L c) 49 m3 From 1.00m height -4..5m 5050.40 m3 247470 height above G.L 10 175 m3 Cement concrete 1:1, 5:3 5913.86 m3 1034925 using 20 mm metal with minimum Reinforcement 11 3900 m3 Supplying and erecting centering for soffits steel 537.00 M2 2094300 sheets of size 90 x60 cm and 10 BG stiffened 12 70 Qtl Steel fabricating 5702.50 Qtl 399175 13 140 m3 Forming sand filter of 1614.32 m3 226005 course sand and fine sand 14 280 m3 Graded filter using broken 1302.45 m3 364686 stone 10 to 80mm 15 70 m3 Gravel filling for protection 1077.11 m3 75398 blocks 16 30 m3 Rough stone dry packing for 1231.72 m3 36951 17 1110 m3 Jeddy stone dry packing for 1269.12 m3 1408718 launching apron 18 L.S Provision for expansion L.S L.S 300000 joints on every 20m interval 19 L.S Provision for bailing out of L.S L.S 250000 water fixing hydrology board, gaugeplates.marking stones etc. 20 L.S Provision for L.S L.S 159000 connection Total 24857461

IV. CO NCLUSION  In this study consist of Surveying, Planning, Designing and Estimation. From this study, by observing the results the following  The Surveying work carried with the instrument of conclusions were made the purpose of the project is increase Auto-Level. the Ground Water recharge through the increase a yield of  The designing and estimation work are done in Ms - Crops. excel software.  The site of check dam is surveyed in the area of  All the Results of design and estimated are found to Kadamalaikundu village of Andipatti thaluk in Theni be safe District.  The IS code of 6966 – 1973 Design is followed

International Journal of Engineering Science and Computing, April 2017 6467 http://ijesc.org/  This method of design is considered to be better than the other methods available for design particularly for check dams  From the design result it has been concluded that this design can be adopted for any check dams.  The estimated cost of the check dam is found to be Total Rs.248.57461 Lakhs.  This amount implies the material cost, labour cost and all other miscellaneous charges.

REFERENCE

[1] Hangxi Fan “The Function of check dams and the effect of Check Dams on Water Erosion” department of resource analysis, saint Marry’s university of Minnesota, winona, MN55987.

[2] IS 6966 – 1973 “criteria for structural design of barriages and ”.

International Journal of Engineering Science and Computing, April 2017 6468 http://ijesc.org/