Civil Engineering Exams (Civil Geo) - Free Online Reviewers

#0. A valve is suddenly closed in a 200 mm dia pipe. The increase in pressure is 700 kPa. Assuming that the pipe is rigid and the bulk modulus of water is 2.07 x 109 N/m2. Compute the celerity of the pressure wave.

A 4506.75 m/s

B 1438.75 m/s

C 14526.72 m/s

D 4549.73 m/s

Answer: 1438.75 m/s

#1. It is a pressure surge of waves caused when a fluid in motion is forced to stop or suddenly change in direction.

A Potential Energy

B Hydro Energy

C hydraulic jump

D water hammer

Answer: water hammer

#2. A valve is suddenly closed in a 200 mm dia pipe. The increase in pressure is 700 kPa. Assuming that the pipe is rigid and the bulk modulus of water is 2.07 x 109 N/m2. Compute the velocity of flow.

A 0.155 m/s

B 0.0482 m/s

C 0.486 m/s

D 0.154 m/s

Answer: 0.486 m/s

#3. A valve is suddenly closed in a 200 mm dia pipe. The increase in pressure is 700 kPa. Assuming that the pipe is rigid and the bulk modulus of water is 2.07 x 109 N/m2. If the length of the pipe is 650 m. long. Compute the water hammer pressure at the valve if it is closed in 3 sec.

A 67.31Kpa

B 20.88Kpa

C 66.67Kpa

D 210.83Kpa

Answer: 210.83Kpa

#4. An 8 m. thick layer of clay under a surcharge loading underwent 80% primary consolidation in 70 days. The clay layer is drained both top and bottom. Find the coefficient of consolidation of clay for the pressure range. Use Tv = 0.567 Hint: use the formula: \( t = \frac{T_v (H_{dr})^2}{Cv}\)

t = time corresponding to degree of consolidation

\(C_v\) = coefficient of consolidation

\(H_{dr}\) = half the thickness of the sample drained on both sides.

\(T_v\) = time factor

A \(0.2592 \frac{m^2}{day}\)

B \(0.1477 \frac{m^2}{day}\)

C \(0.1365 \frac{m^2}{day}\)

D \(0.1296 \frac{m^2}{day}\)

Answer: \(0.1296 \frac{m^2}{day}\)

#5. It is used in drilling operations to determine the in situ undrained shear strength of clay soils particularly soft clays.

A triaxial test

B nuclear method

C rubber balloon

D vane shear

Answer: vane shear

#6. A rectangular block of wood, floats with one face horizontal in a fluid (S = 0.9). The wood density is 750 kg/cu.m. Determine the percentage of wood, which is floated.

A 24%

B 27%

C 21%

D 17%

Answer: 17%

#7. A pump draws water from reservoir A and lifts it to reservoir B as shown. The loss of head from A to 1 is 3 times the velocity head in the 150 mm pipe and the loss of head from 2 to B is 25 times the velocity head in the 100 mm pipe. When the discharge is 25 liters/ sec.
Compute the horsepower output of the pump in kilowatts.

A 48.75 KW

B 48.41KW

C 40.45 KW

D 56.44 KW

Answer: 48.75 KW

#8. A pump draws water from reservoir A and lifts it to reservoir B as shown. The loss of head from A to 1 is 3 times the velocity head in the 150 mm pipe and the loss of head from 2 to B is 25 times the velocity head in the 100 mm pipe. When the discharge is 25 liters/ sec.
Compute the pressure head at 1.

A 19.74 m

B 19.80m

C 20.19m

D 19.20m

Answer: 19.74 m

#9. A pump draws water from reservoir A and lifts it to reservoir B as shown. The loss of head from A to 1 is 3 times the velocity head in the 150 mm pipe and the loss of head from 2 to B is 25 times the velocity head in the 100 mm pipe. When the discharge is 25 liters/ sec.
Compute the pressure head at 2.

A 266.29 m

B 267.95 m

C 275.95 m

D 267.92 m

Answer: 267.95 m

#10. From the given data, shows a sieve analysis of soil samples A, B and C.
SOIL SAMPLE

SIEVE NO. DIAM.(mm) A B C

#4 4.760 94 100 100

#8 2.380 84 90 100

#10 2.000 72 77 98

#20 0.840 66 59 92

#40 0.420 58 51 84

#60 0.250 50 42 79

#100 0.149 44 35 70

#200 0.074 38 33 63

Characteristics of -40 fraction

LL 44 46 47
PL 23 29 24

Classify soil A using AASHTO Method.

SIEVE NO.	DIAM.(mm)	A	B	C
#4	4.760	94	100	100
#8	2.380	84	90	100
#10	2.000	72	77	98
#20	0.840	66	59	92
#40	0.420	58	51	84
#60	0.250	50	42	79
#100	0.149	44	35	70
#200	0.074	38	33	63
		Characteristics	of	-40 fraction
LL		44	46	47
PL		23	29	24

A Soil A is A-2

B Soil A is A-6

C Soil A is A-7-6(3)

D Soil A is A-7-6(13)

Answer: Soil A is A-7-6(3)

#11. From the given data, shows a sieve analysis of soil samples A, B and C.
SOIL SAMPLE

SIEVE NO. DIAM.(mm) A B C

#4 4.760 94 100 100

#8 2.380 84 90 100

#10 2.000 72 77 98

#20 0.840 66 59 92

#40 0.420 58 51 84

#60 0.250 50 42 79

#100 0.149 44 35 70

#200 0.074 38 33 63

Characteristics of -40 fraction

LL 44 46 47
PL 23 29 24

Classify soil B using AASHTO Method.

SIEVE NO.	DIAM.(mm)	A	B	C
#4	4.760	94	100	100
#8	2.380	84	90	100
#10	2.000	72	77	98
#20	0.840	66	59	92
#40	0.420	58	51	84
#60	0.250	50	42	79
#100	0.149	44	35	70
#200	0.074	38	33	63
		Characteristics	of	-40 fraction
LL		44	46	47
PL		23	29	24

A The soil is A-7-6(3)

B The soil is A-7-6(13)

C The soil is A-2-7(1)

D The soil is A-2-7(3)

Answer: The soil is A-2-7(1)

#12. From the given data, shows a sieve analysis of soil samples A, B and C.
SOIL SAMPLE

SIEVE NO. DIAM.(mm) A B C

#4 4.760 94 100 100

#8 2.380 84 90 100

#10 2.000 72 77 98

#20 0.840 66 59 92

#40 0.420 58 51 84

#60 0.250 50 42 79

#100 0.149 44 35 70

#200 0.074 38 33 63

Characteristics of -40 fraction

LL 44 46 47
PL 23 29 24

Classify soil C using AASHTO Method.

SIEVE NO.	DIAM.(mm)	A	B	C
#4	4.760	94	100	100
#8	2.380	84	90	100
#10	2.000	72	77	98
#20	0.840	66	59	92
#40	0.420	58	51	84
#60	0.250	50	42	79
#100	0.149	44	35	70
#200	0.074	38	33	63
		Characteristics	of	-40 fraction
LL		44	46	47
PL		23	29	24

A The soil is A - 7 -6 (3)

B The soil is A - 2 - 7 (3)

C The soil is A - 2 - 7 (13)

D The soil is A - 7 - 6 (13)

Answer: The soil is A - 7 - 6 (13)

#13. A 300 mm diameter test well penetrates 27 m below the static water table. After 24 hours of pumping at 69 lit/sec. The water level is in an observation well at a distance of 98 m from the test well is lowered 0.56 m and the other observation well at a distance of 34.5 m from the test well, the drawdown is 1.10 m.What is the rate of flow in cubic meters per day?

A 7100 cubic meters per day

B 1800.4 cubic meters per day

C 6951.65 cubic meters per day

D 5961.6 cubic meters per day

Answer: 5961.6 cubic meters per day

#14. A 300 mm diameter test well penetrates 27 m below the static water table. After 24 hours of pumping at 69 lit/sec. The water level is in an observation well at a distance of 98 m from the test well is lowered 0.56 m and the other observation well at a distance of 34.5 m from the test well, the drawdown is 1.10 m.What is the coefficient of permeability of the aquifer in m/day?

A 90.10 m/day

B 80.10 m/day

C 70.10 m/day

D 60.10 m/day

Answer: 70.10 m/day

#15. A 300 mm diameter test well penetrates 27 m below the static water table. After 24 hours of pumping at 69 lit/sec. The water level is in an observation well at a distance of 98 m from the test well is lowered 0.56 m and the other observation well at a distance of 34.5 m from the test well, the drawdown is 1.10 m.Compute the transmissibility of the aquifer in square meters per day

A 1843.34 square meters per day

B 1834.34 square meters per day

C 1864.34 square meters per day

D 1884.43 square meters per day

Answer: 1834.34 square meters per day

#16. A thick layer of clay underlies a sand formation having a thickness of 4m. The groundwater is located 2 m below the ground surface. Spgr of the sand and clay is 2.65 with sand having an average void ratio of 0.52. The clay has a water content of 42% degree of saturation above the water table is 0.37. Compute the moist unit wt. of the sand

A 17.43 Kn/cu. m.

B 18.34 Kn/cu. m.

C 19.62 Kn/cu. m.

D 18.56 Kn/cu. m.

Answer: 18.34 Kn/cu. m.

#17. A thick layer of clay underlies a sand formation having a thickness of 4m. The groundwater is located 2 m below the ground surface. Spgr of the sand and clay is 2.65 with sand having an average void ratio of 0.52. The clay has a water content of 42% degree of saturation above the water table is 0.37. Compute the total stress at a depth of 10 m. below the ground surface.

A 186.24 kPa

B 183.02 kPa

C 192.45 kPa

D 182.42 kPa

Answer: 182.42 kPa

#18. A thick layer of clay underlies a sand formation having a thickness of 4m. The groundwater is located 2 m below the ground surface. Spgr of the sand and clay is 2.65 with sand having an average void ratio of 0.52. The clay has a water content of 42% degree of saturation above the water table is 0.37. Compute the effective stress at a depth of 10 m. below the ground surface.

A 103.94 kPa

B 130.49 kPa

C 128.24 kPa

D 182.42 kPa

Answer: 103.94 kPa

#19. Water from a reservoir flowing through a pipe having a diameter of 600 mm with a velocity of 1.75 m/s is completely stopped by a closure of a valve situated 150 m from the reservoir. Assume that the pressure increases at a uniform rate and there is no damping of the pressure wave. The pipe has a thickness of 20 mm and bulk modulus of water is 2.2 x 10 ⁹ N/m² and modulus of elasticity of the steel is 1.4 x 10¹¹N/m². Compute the celerity of the pressure wave

A 1232 m/s

B 1202 m/s

C 1223 m/s

D 1332 m/s

Answer: 1223 m/s