DESIGN AND DETAILING OF WATER TANK

Data and dimension calculations:Capacity of Water Tank = 135lpcd ×[4 members × (7+(8×8))] = 38340 litre/day

Length = 4.5m , Width = 2.15m 

Height =  

Free board=0.27m

Total Height with free board = 1.98+.27 = 2.25m

Joint conditionAll vertical joints are rigid and Horizontal Joints of walls and slabs are hinged 

Moment Calculations:  FROM IS 3370 (PART 4); TABLE 3

MH max = Mywa3 , MV max = Mxwa3 W = 9800N/mm2

 Long Wall:  Length (b) = 4.5m , Height (a) = 2.25m

From IS3370 (Part 4) 1967, TABLE 3@ mid of the wall  MH max = 0.027×9800×2.253 (sagging) , 0.017×9800 × 2.253 (Hogging)

MH max = 3013.95 N-m (sagging), 1897 N-m (Hogging)

MV max = 0.015×9800×2.2×53 (sagging) , 0.086×9800 ×2.253 (Hogging)

MV max = 1674.4 N-m (sagging) , 9600 N-m (Hogging)  @ edge of the wall

MH max = 0.059 ×9800 ×2.253 = 6697.68 N-m (Hogging)

Mv max = 0.01×9800×2.253 = 1116.3 N-m (Hogging)

Shear Force From IS3370 (PART 4) , TABLE-7 @ mid point of edge of wall  SF = 0.3604wa2 = 17880.34 N Short Wall:Length (b) =2.15m , Height(a)=2.25m

From IS3370 (Part 4) 1967 TABLE 3 @ mid of the wall MH max = 0.011×9800×2.253 (sagging) , 0.008×9800 ×2.253 (Hogging)MH max = 1451 N-m (sagging) , 893 N-m (Hogging)

MV max = 0.009×9800×2.253 (sagging) , 0.035×9800 ×2.253 (Hogging)

MV max = 1004 N-m (sagging) , 3906.98 N-m (Hogging)

@ edge of the wall  MH max = 0.029 ×9800 ×2.253 = 3237.2 N-m (Hogging) Mv max = 0.006×9800×2.253 = 669.76 N-m (Hogging) Shear Force From IS3370 (PART 4) , TABLE-7 @ mid point of edge of wall SF = 0.258wa2 = 12809.9N

Reinforcement @ edge of Long Wall:

MH max =6697.68 N-m (Hogging) On Water faceM = σstAstJd assuming Thickness (t) =200mm , d=200-30=170mm σst = 115 N/mm2 IS3370 Part 2 (Table 4)σcbc = 8.5 N/mm2 IS3370 Part 2 (Table 2)k = =  J = 1-(K/3) = 0.8506Ast1 = mm2

T = 12809.9NAst2 =2

Total Ast = 402.7+111.39=514.092

IS3370 Part 2 cl. 8.1.1Ast min = 0.4% of c/s= 0.004×1000×200 = 8002

So provide Ast min = 8002  Assume diameter of bar Ø = 10 mmS == 95mm Provide 10mm bar @ 95mm c/c Distance on Water face

Stress check

From IS3370 (P-2) , cl-6.3(b)

σcbt’ = N/mm2

σcbt = 1.8 N/mm2 IS3370 Part 2 (Table 1)

σct’ = N/mm2

σct = 1.3 N/mm2 IS3370 Part 2 (Table 1)   < 1

Shear check:

τv max = N/mm2

Pt = = IS 456 TABLE 19M25 τc = 0.47 > 0.1051 So safe In top and bottom slab providing minimum reinforcement 

REINFORCEMENT DETAILING