Configuration RCC Box type

Materials Concrete Gr M25Reinf. Steel Fe415

Loading1 Dead load Unit wt. Of concrete at 2.50T/cu.m

Unit wt. of Dry soil γ 1.80T/cu.mUnit wt. of Saturated soil γ' 2.10T/cu.m

2 Live load 500Kg/sqm on floors Unless other wise specified(not critical for design)

3 Equipment Load weight of conveyor short supports (not critical for design)

4 Earth pressurecase 1 Dry case with unit weight of soil = 1.80T/cu.m (Kaγh)case 2 Water table case above WT = 1.80T/cu.m (Kaγh)

below WT = 1.10T/cu.m water pr+sub soil prKa (earth pressure coefficient) Ka = 0.5

will be based on earth pressure at restNote Case 2 is critical for design , hence the same is considered

Live load surcharge pressure 1.00T/sqmOn Walls 1*0.5= 0.50T/sqm

DESIGN OF TUNNEL FOR CONVEYOR

6 Seismic loads Zone - II (As per IS:1893)Tunnel being an underground structure seismic loads are not Considered in the Analysis and design

7 Wind loads Basic Wind Speed, Vb = 50m/s Terrain catagery = 2(As per IS:875) Tunnel being an underground structure Wind loads are not

Considered in the Analysis and design

Load combinations 1 DL+Earth Pressure2 DL with out earth pressure from sides

Reference 1. IS:456-20002. Reynolds Hand Book for R.C. Designers3. SP:16-1978 (Design Aids for IS:456-2000)

Loading AnalysisSoil Above Slab = 0.000 m

300.00 300 -0.400 (T.O.Slab)300 Water Table

3000

-3.700400 (T.O. RAFT SLAB)

300 5000 300Fig. Cross Section(HORIZONTAL PORTION)(HORIZONTAL PORTION)

h= 3000+300/2+400/2 = 3350mm

l = 5000+(300+300)/4+(300+300)/4 = 5300mm

1 Uniform load on Roof:Load due to saturated earth = 2.1*0 = 0.00T/sq.mLoad from Surcharge = 1.00T/sq.mTotal uniform load on Roof = 1.00T/sq.mSelf weight of roof slab = assuming300thk.= 0.75T/sq.mTherefore, q = 1+0.75 = 1.75T/sq.m

2 Weight of Wall:Average wall thickness = (300+300)/2 300mmCenter to center between walls = 5300mmWeight of wall = 2x0.3x2.5x3 = 4.50T/mTherefore, q' = 4.5/(5.3+0.3) = 0.80T/sq.m

3 Pressure on Wall:

At Base (At D)1 Pressure due to water = 1.0*(3.7-0.4) = 3.30T/sq.m 0.50T/sq.m 0.47T/sq.m2 Pressure due to submerged soil = (2.1-1.0)x0.5x3.3 = 1.82T/sq.m3 Pressure due to Surcharge = 0.5x1 = 0.50T/sq.m

At Top (AT B) Since soil is submerged 1 Pressure due to Water = 1.00x(0-0.4) = 0.30T/sq.m2 Pressure due to submerged soil = (2.1-1.0)x0.5x0.4 = 0.17T/sq.m3 Pressure due to Surcharge = 0.5x1 = 0.50T/sq.m

These summation of loads entered in Staad modelDue to the Shear design criteria heavy thickness provided

5.12T/sq.m

A B

C D

q

q

q'

A

C D

A B

C

Moment (T-m/m) B (mm) D (mm) d (mm) Mu/bd2 Pt Reqd. Ast3.539 1000 300 219 1.107 0.324 709.9031472.609 1000 300 219 0.816 0.235 515.3175914.566 1000 400 319 0.673 0.193 614.6151944.403 1000 400 319 0.649 0.186 591.9531230.654 1000 300 219 0.205 0.057 125.319823

Fck= 25 Fy= 415 dc= 75Dia Spacing Spacing pr. Acutual Pt Shear (T) Tv (Mpa) Tc (Mpa) Check12 159.31 200 0.258 4.55 0.312 0.370 OK12 219.47 200 0.258 0 0.000 0.370 OK12 184.01 150 0.236 7.109 0.334 0.356 OK12 191.06 150 0.236 0 0.000 0.356 OK12 902.47 150 0.344 0.348 0.024 0.418 OK

CHECK FOR BUOYANCY & CORRESPONDING UNIT LENGTH OF TUNNELWeight of concrete from roof = 4.200TWeight of concrete from wall = 4.500TWeight of concrete from raft = 5.600TWt. of saturated soil above Slab= 0.000TWt of Hooper 0.000T

Total downward Load = 14.300TTotal upward load = 20.720TInteraction Ratio= 0.621

<1.2, Hence Not O.K.

Mid span CDSpan AC & BD

Reinforcement Details and Shear Check

LocationAt sup A & BMid span ABAt sup C & D

Mid span ABAt sup C & DMid span CD

Span AC & BD

LocationAt sup A & B

Input To STAADSTAAD PLANEINPUT WIDTH 79UNIT METER KNJOINT COORDINATES1 0 0 0;2 5.3 0 0;3 0 3.35 0;4 5.3 3.35 0;5 0 -0.2 0;6 5.3 -0.2 0;MEMBER INCIDENCES1 1 2; 2 3 4; 3 1 3; 4 2 4; 5 5 1; 6 6 2;DEFINE MATERIAL STARTISOTROPIC CONCRETEE 2.5e+007POISSON 0.17DENSITY 25ALPHA 1e-005DAMP 0.05END DEFINE MATERIALMEMBER PROPERTY INDIAN1 PRIS YD 0.4 ZD 12 PRIS YD 0.3 ZD 13 TO 6 PRIS YD 0.3 ZD 1CONSTANTSMATERIAL CONCRETE ALLSUPPORTS5 6 FIXED BUT FX FZ MX MY MZLOAD 1 LOADTYPE on RoofMEMBER LOAD1 UNI GY 17.172 UNI GY -17.17LOAD 2 LOADTYPE on Base due to WallsMEMBER LOAD1 UNI GY 7.88LOAD 3 LOADTYPE on Base due to Earth PressureMEMBER LOAD3 TRAP Y -56.15 -9.654 TRAP Y 56.15 9.65LOAD COMB 4 COMBINATION LOAD CASE 41 1.0 2 1.0 3 1.0 PERFORM ANALYSISFINISH