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AS PER CA MAP SEPERATELY DRAWN AS PER CA MAP SEPERATELY DRAWN

A

Arreeaa == 332255..000000 SSqqkkmm approximateapproximate ..

Calculation of Discharge by Catchment Area Method

Q

Q == c x Mc x M3/43/4 w

whheerre e Q Q == DDiisscchhaarrgge e iin n ccuummeeccss c

c== CCoonnssttaanntt == 1144 M

M == CCaattcchhmmeennt t AArreea a iin n SSqqkkm =m = 332255..000000 Q

Q == 114 4 x x 332255 3/43/4 == 11007711..6622 CCuummeeccss

R

Reedduucceed d lleevveel l aatt 115500..000000 m m UUppssttrreeaam m == 9933..225599 mm R

Reedduucceed d lleevveel l aatt 110000..000000 m m DDoowwnnssttrreeaam m == 9922..998833 mm T

ToottaallDDiissttaannccee == 225500..000000 mm S

Sllooppe e = = (( 9933..225599 -- 9292..998833 ) ) == 00..0000110000

Catchment Area Calculations

Calculation of Bed Slope

250.00 250.00

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Calculation of Discharge by Area Velocity Method :

Cross section @ Site of crossing MFL = + 100.000 m

HFL G.L Depth of Flow Distance Mean Depth Area Perimeter

100.000 100.000 0.000 0.000 0.000 0.000 0.000 100.000 98.981 1.019 10.000 0.510 5.095 10.052 100.000 98.295 1.705 10.000 1.362 13.620 10.024 100.000 97.983 2.017 10.000 1.861 18.610 10.005 100.000 97.929 2.071 10.000 2.044 20.440 10.000 100.000 97.952 2.048 10.000 2.060 20.595 10.000 100.000 98.055 1.945 10.000 1.997 19.965 10.001 100.000 98.183 1.817 10.000 1.881 18.810 10.001 100.000 98.337 1.663 10.000 1.740 17.400 10.001 100.000 98.411 1.589 10.000 1.626 16.260 10.000 100.000 98.428 1.572 10.000 1.581 15.805 10.000 100.000 98.389 1.611 10.000 1.592 15.915 10.000 100.000 98.350 1.650 10.000 1.631 16.305 10.000 100.000 98.054 1.946 10.000 1.798 17.980 10.004 100.000 97.538 2.462 10.000 2.204 22.040 10.013 100.000 96.909 3.091 10.000 2.777 27.765 10.020 100.000 96.388 3.612 10.000 3.351 33.515 10.014 100.000 95.101 4.899 10.000 4.256 42.555 10.082 100.000 94.227 5.773 10.000 5.336 53.360 10.038 100.000 93.295 6.705 10.000 6.239 62.390 10.043 100.000 93.351 6.649 10.000 6.677 66.770 10.000

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100.000 94.116 5.884 10.000 6.267 62.665 10.029 100.000 94.837 5.163 10.000 5.524 55.235 10.026 100.000 95.683 4.317 10.000 4.740 47.400 10.036 100.000 96.541 3.459 10.000 3.888 38.880 10.037 100.000 97.453 2.547 10.000 3.003 30.030 10.042 100.000 98.365 1.635 10.000 2.091 20.910 10.042 100.000 99.277 0.723 10.000 1.179 11.790 10.042 100.000 100.000 0.000 10.000 0.361 3.615 10.026 795.720 280.577 Mean Radius, R = A / P = 795.720 = 2.836 m 280.577 Slope of drain bed, S = 0.0010 Rugosity Coefficient, n = 0.045

Velocity V = 1 / n x R2/3x S1/2 = 1.408 m / sec ` Discharge, Q = A * V = 1120.374 Cumecs

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Cross section at 100m Upstream MFL = + 100.100 m

100.100 100.100 0.000 0.000 0.000 0.000 0.000 100.100 98.361 1.739 100.000 0.869 86.950 100.015 100.100 97.909 2.191 5.000 1.965 9.825 5.020 100.100 96.478 3.622 5.000 2.906 14.533 5.201 100.100 94.345 5.755 5.000 4.689 23.443 5.436 100.100 93.276 6.824 5.000 6.290 31.448 5.113 100.100 94.325 5.775 5.000 6.299 31.498 5.109 100.100 95.444 4.656 5.000 5.215 26.078 5.124 100.100 97.926 2.174 5.000 3.415 17.075 5.582 100.100 98.427 1.673 5.000 1.923 9.617 5.025 100.100 100.100 0.000 100.000 0.836 83.650 100.014 334.115 241.639 Mean Radius, R = A / P = 334.115 1.383 m 241.639 Slope of drain bed, S = 0.0010 Rugosity Coefficient, n = 0.045

Velocity V = 1 / n x R2/3x S1/2 = 0.872 m / sec Discharge, Q = A * V = 291.348 Cumecs

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Cross section at 100m Downstream MFL = 99.900 m

99.900 99.900 0.000 0.000 0.000 0.000 0.000 99.900 96.985 2.915 100.000 1.458 145.750 100.042 99.900 95.235 4.665 5.000 3.790 18.950 5.297 99.900 94.866 5.034 5.000 4.850 24.248 5.014 99.900 93.434 6.466 5.000 5.750 28.750 5.201 99.900 92.983 6.917 5.000 6.692 33.458 5.020 99.900 93.399 6.501 5.000 6.709 33.545 5.017 99.900 94.883 5.017 5.000 5.759 28.795 5.216 99.900 95.323 4.577 5.000 4.797 23.985 5.019 99.900 97.015 2.885 5.000 4.676 23.378 6.150 99.900 98.960 0.940 5.000 1.913 9.563 5.365 99.900 99.900 0.000 100.000 0.470 47.000 100.004 417.420 247.346 Mean Radius, R = A / P = 417.420 = 1.688 m 247.346

Slope of drain bed, S = 0.0010 Rugosity Coefficient, n = 0.045

Velocity V = 1 / n x R2/3x S1/2 = 0.996 m / sec Discharge, Q = A * V = 415.750 Cumecs

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S.No HFL(m) Discharge

1 100.100 291.348 Cumecs

2 100.000 1120.374 Cumecs

3 99.900 415.750 Cumecs

The Discharge obtained from Area velocity method at upstream, site of crossing and downstream are mentioned above.

The Discharge obtained from Catchment area is = 1071.62 Cumecs. Hence, the design di shcarge is consi dered as = 1120.37 Cumecs

Site of crossing 100 m D/S

Design Discharge

SUMMARY OF DISCHARGE

Location 100m U/ S

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Calculation of Linear Water way

Discharge Q = 1120.374 Cumecs HFL = 100.000 m

Sil l l ev el = 93.500

Velocity of flow = 1.408 m / Sec

Depth of flow d = 100 - 93.5 = 6.500 m Afflux (x)= 0.15 m ( Assumed)

Head due to Afflux ha = V2_d2]_{/ [(d+x)}2_{* 2 * 9.81]}

= ( 1.408 ^ 2 ) x ( 6.5 ^ 2 ) ( 6.5 + 0.15 ) ^ 2 x ( 2 x 9.81 )

= 0.097 m

Combined Head (ha + x) = 0.15+ 0.097 = 0.247 Velocity through vents Vv = 0.9 v [2*g*(ha+x)]

= 0.9 x SQRT { 2 x 9.81 x ( 0.247 ) }

= 1.981 m / Sec

Linear Water Way = Q / (Vv* d) = 1120.374 = 87.009 m

( 1.981 x 6.5 ) Skew Angle is = 0 o

Linear water way in skew is = 87.009 SAY 87.000 m PROVIDE LWW = 80 as per site condition

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CALCULATION OF SCOUR DEPTH

Normal Scour Depth HFL = 100.000 m Sill lev el = 93.500 Db = Q / L = 1120.37 = 12.878 m 80.00 dsm = 1.34 * (Db / ksf) 1/3 Silt factor ksf = 2.00 dsm = 1.34 x ( 12.878 ^ 2 / 2 ) = 5.835 m

Normal Scour Depth = dsm = 5.835 m below HFL

Pier

Max Scour Depth = 2.0xdsm = 11.670 m

Grip length = ( 1 / 3 ) x 11.67 = 3.890 m

Max Scour Depth including grip length = 11.67 + 3.89 = 15.560 m Foundation Level = HFL - Max Scour Depth including grip length

= 100 - 15.56 = 84.440 m

Say 84.400 m

Depth below sill level= Sill level - Foundation Level

= 93.5 - 84.4 = 9.100 m

ABUTMENT

Max Scour Depth = 1.27xdsm= 7.410 m

Grip length = ( 1 / 3 ) x 7.41 = 2.470 m

Max Scour Depth including grip length = 7.41 + 2.47 = 9.880 m Foundation level = HFL - Max Scour Depth including grip length

= 100 - 9.88 = 90.120 m

Say 90.100 m

Depth below sill level= Sill level - Foundation Level

= 93.5 - 90.1 = 3.400 m

Soft Rock is availble at shallow depth of 1.0m below sill

Propose OPEN FOUNDATION with 1.5 m embedment in soft rock

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Linear W ater way requried in normal direction = 80.000 m Economical span = 1.5 ( HFL + 1.2 + 0.15 - 91 )

= 1.5 ( 100 + 1.2 + 0.15 - 91 )

= 15.525 m

Provide 5 Vents of 16.5 m (eff.) with Open foundation

HFL = 100.000 m

Vertical Clearance = 1.200 m

Afflux = 0.15 m

Deck slab thickness = 1.675 m

Bottom of Deck = HFL + AFFLUX + VC

= ( 100 + 1.2 + 0.15 ) = 101.350 m RCL = Bottom of Deck + Deck thickness + wearing coat

= ( 101.35 + 1.675 + 0.100 ) = 103.125 m

FIXING OF RCL

SPAN ARRANGEMENT

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1) Design Discharge, Q = 1120.37 Cumecs

2) HFL = 100.000 m

3) Velocity = 1.408 m/sec

4) SillLevel = 93.500 m

5) Carriage way width = 7.50 m

6) Span arrangement = 5 vents of 16.5 m ( eff )without footpath

7) RCL = 103.125 m

8) Bottom of Deck = 101.350 m

9) Type of Sub Strcuture

Pier = VCC M15 W ALL TYPE with skin rft Abutment = VCC M15 Wall Type with skin rft

Return Wall = VCC M15 BOX Type with skin rft 10) Type of Foundation = Open foundation for Piers,

Abutments and wingwalls 11) Foundation Lev els

Pier = 91.000 m SR-1.5m

Abutment = 91.000 m SR-1.5m

Return wall = 94.500 m GL-3.0m

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Name of work: TWSD- Construction of Bridge across Masivagu

on Narayanapuram to Mittapallliroad at Km 10/800

in Yellandu mandal of Khammam Dist

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