Quiz: Civil Engineering
Exam: GATE
Topic: Miscellaneous
Each question carries 1 mark
Negative marking: 1/3 mark
Time: 20 Minutes
Q1. If the soil sample having porosity 60% and degree of saturation at 80% then its percentage air voids is:
(a) 5%
(b) 12%
(c) 18%
(d) 20%
Q2. The water flow fully through the rectangular channel of latrel dimensions 5m × 4m. what is the velocity of flow (m/sec) through the channel, if the slope of energy line and Chezy’s constant as 0.0006 and 90 respectively?
(a) 4.6
(b) 2.7
(c) 2.2
(d) 1.5
Q3. While designing a hydraulic structure, the piezometric head at bottom of the floor is computed as 10m. the datum is 3m below floor bottom. The assured standing water depth above the floor is 2m. the specific gravity of the floor material is 2.5 the floor thickness should be
(a) 6.00 m.
(b) 4.40 m.
(c) 3.33 m.
(d) 2.00 m.
Q4. A flow net of a coffer dam foundation has 6 flow channels and 18 equipotential drops. The head of water lost during seepage is 6m. if the coefficient of permeability of foundation is 4×10^(-5) m/min, then the seepage loss per meter length of dam will be
(a) 34.56×10^(-2) m^3/day
(b) 11.52×10^(-2) m^3/day
(c) 6.48×10^(-2) m^3/day
(d) 2.10×10^(-2) m^3/day
Q5. Two similar bars of steel and aluminium are heated to a same temperature. Forces are applied at the ends of the bars to maintain their lengths unaltered. If the ratio of young’s modulus of steel and aluminium is 3, and the ratio of the coefficients of thermal expansion of steel to that of aluminium is 0.5, what is the stress on the aluminium bar if the stress on the steel bar is 100 MPa?
(a) 150.0 MPa
(b) 136.7 MPa
(c) 66.7 MPa
(d) 16.7 MPa
Q6. Considering beam as axially rigid, the degree of freedom of a plane frame shown below is
(a) 6
(b) 7
(c) 8
(d) 9
Q7. As per IS 456:2000 for the design of reinforced concrete beam, the maximum allowable shear stress (τ_cmax ) depends on the
(a) grade of steel only
(b) grade of concrete only
(c) grade of concrete and grade of steel
(d) grade of concrete and percentage of reinforcement
Q8. A ship has a metacentric height of 0.90 m and its period of rolling is 20 seconds. The relevant radius of gyration is nearly
(a) 5.5 m.
(b) 7.5 m
(c) 9.5 m
(d) 11.5m
Q9. The magnetic bearing of a line (on full circle mensuration basis) is 55° 30’ East and the magnetic declination is 5° 30’ East. the true bearing of the line will be.
(a) 50° 00’
(b) 40° 00’
(c) 55° 30’
(d) 61° 00’
Q10. The concrete mix design is conducted as per
(a) IS: 383
(b) IS: 456
(c) IS: 10262
(d) IS: 13920
Solutions
S1. Ans.(b)
Sol. Given, porosity (n) = 60% = 0.6
Degree of saturation (S) = 80% = 0.8
Percentage air voids (η_a ) = ?
Now,
S+a_c=1
0.8+a_C=1
▭(a_C=0.2 ) (Air content)
η_a=n×a_C (Percentage air voids)
=0.6×0.2
=0.12
▭(η_a=12%)
S2. Ans.(b)
Sol. velocity of flow (v) = C√RS
C = Chezy’s constant = 90
R = hydraulic radius = A/P
=((5×4))/((5+2×4) )
▭(R=20/13)
S=Slope=0.0006
V=90√(20/13×0.0006)
▭(V=2.7 m\/sec.)
S3. Ans.(c)
Sol. floor thickness (t) = h/(G-1)
h=10-(3+2)
▭(h=5m.)
t=5/(2.5-1)
▭(t=3.33m)
S4. Ans.(b)
Sol. Given,
Number of flow channel (N_F )=6
Number of equipotential drops (N_d )=18
Co-efficient of permeability (K) = 4×10^(-5) m\/min
=0.0576 m\/day
Head of water (H) = 6m
Now,
Seepage loss per metre length (q) = kH N_F/N_d
=0.0576×6×6/18
▭(q=11.52×10^(-2) m^3 \/day)
S5. Ans.(c)
Sol. Given,
E_s/E_a =3, α_s/α_a =0.5
σ_s=100 MPa.,σ_a= ?
Thermal stress in bar σ = Eα ∆ T
Here
σ_S/σ_a =E_S/E_a ×α_S/α_a ×∆T/∆T
100/σ_a =3×0.5
▭(σ_a=66.7 MPa)
S6. Ans.(c)
Sol. No. of joints (j) = 4
No of external reaction (re) = 3
Axially rigid member (m) = 1
Now, Degree of kinematic indeterminacy or degree of freedom –
D_k=3j-re-m
=(3×4)-3-1
▭(D_k=8 )
S7. Ans.(b)
Sol. As per IS456:2000 for the design of reinforced concrete beam, the maximum allowable shear stress (τ_cmax ) depends on the grade of concrete only.
S8. Ans.(c)
Sol. we know, ▭(T=2π √(k^2/(g.(GM) ̅ )))
Given,
T=20 sec.
(GM) ̅=0.90 m.
20= 2π √(k^2/(9.81×0.9))
K^2=((20)^2×9.81×0.9)/(2π)^2
▭(K=9.459m.)
S9. Ans.(d)
Sol.
True bearing of line AB = magnetic bearing of line AB + magnetic declination
= 55°30’ + 5°30’= 61°00’
S10. Ans.(c)
Sol. IS :10262 → concrete mix design
IS :456 → Reinforced concrete
IS :1343 → Prestress concrete
