DEGREES BEND

1. Thrust Block Parameters.

TABLE

Soil Bearing Capacity, SBC = kPa

Operating Pressure, PO = bars = kN/m2

Area of Pipe, AP = m2

= 0.382 Cos θ/2 = =

T P

Thrust, TV = T sin (θ/2) = 0.84 kN

Thrust, TH = T cos (θ/2) = 2.02 kN

Hydro Static Pressure, PT = kN/m2

Thrust, T = 3.97 kN

Thrust, TV = T sin (θ/2) = 1.257 kN

Thrust, TH = T cos (θ/2) = 3.035 kN

Pipe Self weight = 0.02 Kn/m (From Amiantit Fiberglass product guide (5000 STIS))

Weight of water = 10 kn/m

Weight of concrete = 24 kn/m3

Saturated weight of soil = 8 kn/m3

Factor of safety for Overturning (Fso) = 1.5

Factor of Safety (Fss) = 1.5

Factor of Safety for Buoyancy (Fsu) = 1.2

Coefficient of friction of soil µ = 0.4

Pipe Cover , Cp = 1200 mm to top of pipe,see note 9 below

Depth of Cover , H1 = 745 mm to top of pipe,see note 9 below

Passive Pressure Coefficient kp = 3

675

1.395

100.00

4.50 450

0.0064

300 1200 500

Sin θ/2 0.924

600 1000 70090 1000 900 1200 500

VERTICAL THRUST - UPWARD 90MM PIPE

45.0

PIPE DIAMETER

(mm)A B L D C G E H

SOIL FILL

H1F

CONCRET

E VOLUME

(m3)

DEGREES BEND

VERTICAL THRUST - UPWARD 90MM PIPE

45.0

F = 500

B =

A = 1000

T

A3 C = 600

A2G = 1000

A4E = 700 90

D = 500 A1H = 300

L = 1200

2. Center of mass

A1 M2

A2 M2

A3 M2

A4 M2

TOTAL VOLUME 1.4 M3

X M

Y M

3.WEIGHT OF SATURATED SOIL OVER THRUST BLOCK

FILL OVER PIPE Fill 1 1.39 m3

FILL OVER THRUST BLOCK Fill 2 1.08 m3

Volume of total fill Ftotal 2.47 m3

Volume x saturated unit weight Ff 19.7 Kn

4. BUOYANCY OF THRUST BLOCK FOR UPLIFT AND SLIDING

VOLUME OF THRUST BLOCK = M3

UPLIFT FORCE FB = Kn

THRUST BLOCK SELF WEIGHT

1.395

13.95

900

0.82

0.67

0.6

0.5

0.3

0.15

DEGREES BEND

VERTICAL THRUST - UPWARD 90MM PIPE

45.0

BLOCK FORCE MOM ABT P

F1 12.96 M1 7.776

F2 10.8 M2 2.7

F3 6.48 M3 1.62

F4 3.24 M4 0.54

5.WEIGHT OF SATURATED SOIL OVER THRUST BLOCK

F5 11.088 kn

M5 9.4248 knm

F6 4.32 kn

M6 1.08 knm

F7 4.32 kn

M7 1.08 knm

6.BUOYANCY OF THRUST BLOCK FOR UPLIFT AND SLIDING

F8a 5.4 kn

M8a 4.59 knm

F8b 4.5 kn

M8b 1.125 knm

F8c 2.7 kn

M8c 0.675 knm

F8d 1.35 kn

M8d 0.23 knm

7.WEIGHT OF WATER IN PIPE AND PIPE SELF WEIGHT

F9 0.10 kn

M9 0.06 knm

F10 0.04 kn

M10 0.01 knm

DEGREES BEND

VERTICAL THRUST - UPWARD 90MM PIPE

45.0

8.PASSIVE RESISTANCE OF SOIL

Top of thrust block passive pressure , P1 = H1 kp

= 2.235 kpa

Bottom of thrust block passive resistance P1 = (H1+G+D) kp

= 6.735 kpa

Pavg = 4.49 kpa

Average thrust block passive pressurePavg (D+G)B

6.05475 kn

M11 = 4.5410625 knm

EVALUATE FOR OVERTURNING

Evaluated for Design pressure

FOR OVERTURNING

TVD 0.84 KN

MTVD 0 KNM

THD 2.02 KN

MTHD 2.0234824 KNM

DEGREES BEND

VERTICAL THRUST - UPWARD 90MM PIPE

45.0

TV

F3

F2TH

F4

F1

F6 F7

F5

F8

O

F9

F10

O

DEGREES BEND

VERTICAL THRUST - UPWARD 90MM PIPE

45.0

F8c

F8b F8d

F8a

MR = M1+M2+M5+M6+M8c+M8d+M9 21.94 KNM

MO = M3+M4+M7+M8a+M8b+M10+MTH+MTV 10.99 KNM

FOS overturning SAFE

EVALUATED AT HYDROTEST PRESSURE

TVT 1.2565229 KN

MTVD 0 KNM

THT 3.0352236 KN

MTHD 3.0352236 KNM

MR M1+M2+M5+M6+M8c+M8d+M9+M1126.48 KNM

MO M3+M4+M7+M8a+M8b+M10+M 12.00 KNM

FOS overturning 2.21 SAFE

EVALUATE FOR SLIDING

Evaluated for Design pressure

Friction Resistance

(VT. WC + FF) µ 21.2832 KN

THT 2.02 KN

FACTOR OF SAFETY AGAINST SLIDING 10.52 SAFE

Evaluated for Hydrotest pressure

.

Friction Resistance

(VT. WC + FF) µ + F11 27.33795 KN

THT 3.04 KN

FACTOR OF SAFETY AGAINST SLIDING 9.01 SAFE

2.00

DEGREES BEND

VERTICAL THRUST - UPWARD 90MM PIPE

45.0

Evaluated for Buoyancy

.

Evaluated at Design Pressure

Fu = VT WC + FF 53.21

TVD+VT WW 14.79 KN

FACTOR OF SAFETY AGAINST BUOYANCY3.60 SAFE

Evaluated at Hydrotest Pressure

Fu = VT WC + FF 53.21

TVD+VT WW 15.21 KN

FACTOR OF SAFETY AGAINST BUOYANCY 3.50 SAFE

SUMMARY OF RESULTS

PIPE DIAMETER = 90 MM

SYSTEM DESIGN PRESSURE = 450 KN/M2

SYSTEM HYDROSTATIC PRESSURE= 675 KN/M2