**Quiz: Civil EngineeringExam: All AE/JE ExamsTopic: Miscellaneous**

**Each question carries 1 markNegative marking: 1/4 markTime: 10 Minutes**

Q1. In some brick masonry walls, patches of whitish crystal were found on the exposed surfaces, also chipping and spalling of bricks took places from the same walls. Which among the following are the causes of these defects?

1.Settlement of foundation

2.Over-loading of the wall

3.Sulphate attack

4.Efflorescence

(a) 1 and 2

(b) 2 and 3

(c) 2 and 4

(d) 3 and 4

Q2. If the tensile stress of a steel bar of diameter d is 140 N/mm² and the bond stress is 0.6 N/mm², the required bond length will be:

(a) 45 ϕ

(b) 50 ϕ

(c) 53 ϕ

(d) 59 ϕ

Q3. Shear strength in double shear in riveted joints is given by:

(a) (πd^2)/4 f_s

(b) (2πd^2)/4 f_s

(c) π/4 〖df〗_s

(d) none of the above

Q4. The pressure within the cylinder of a hydraulic press is 9 MPa. The inside diameter of the cylinder is 500 mm. If the permissible tensile stress is 180 N/mm², the minimum wall thickness of the cylinder is:

(a) 12.5 mm

(b) 16 mm

(c) 9 mm

(d) 18 mm

Q5. The relationship, between number of joints (j), and the number of members (m), in a perfect truss, is given by

(a) m = 3j – 2

(b) m = 2j – 3

(c) m = j – 2

(d) m = 2j – 1

Q6. What is the kinematic indeterminacy for the frame shown above? (member inextensible)

(a) 6

(b) 11

(c) 12

(d) 21

Q7. The total line lies over the hydraulic gradient line by an amount equal to:

(a) Velocity head, V²/2g

(b) datum head, Z

(c) Sum of pressure, velocity and datum heads

(d) Pressure head, P/y

Q8. A tape of length l and weight W kg is suspended at its ends with a pull of p kg, the sag correction is:

(a) (l^2 w^2)/(24p^2 )

(b) (l^2 w^3)/(24p^2 )

(c) (lw^2)/(24p^2 )

(d) (l^2 w^2)/(24p^3 )

Q9. The green house gases as per their decreasing order of effectiveness are –

(a) CO₂, CH₄, N₂O and CFC

(b) CH₄, CO₂, N₂O and CFC

(c) N₂O, CH₄, CO₂ and CFC

(d) CFC, CH₄, CO₂ and N₂O

Q10. A partially saturated sample of soil has a unit weight of 2.0 g/cm³ and specific gravity of soil particles is 2.6. If the moisture content in the soil is 20%, the degree of saturation is:

(a) 20%

(b) 77%

(c) 92%

(d) None of these

Solutions

S1. Ans.(d)

Sol.

- The patches of whitish crystal were found on the exposed surface is due to efflorescence.
- The chipping and spalling of bricks are due to sulphate attack.

S2. Ans.(d)

Sol. Development length (L_d ) = ϕσst/4τbd

τbd=0.6N\/mm^2

σst=140N\/mm^2

L_d=(ϕ×140)/(4×0.6)

▭(L_d=58.33ϕ≈59ϕ)

S3. Ans.(b)

Sol. Shear strength in double shear rivetted joint

=2×π/4 d^2×σ_Sp

d → gross diameter

σ_sp → permissible shear stress.

S4. Ans.(a)

Sol. maximum stress inside thin cylinder.

σ_ind= Pd/2t

180 = (9×500)/2t

t = 12.5 mm

S5. Ans.(b)

Sol. m = 2j-3

Where m = No. of truss member

J =No. of joint in the truss.

S6. Ans.(b)

Sol. No.of inextensible members (m) =10

No.of joints (j) =9

No.of external reactions (r_e) =6

Internal hinged reactions (r_r) =0

Kinematic indeterminacy (D_k) =3j-r_e-m+r_r

=(3×9)-6-10+0

▭(D_k=11)

S7. Ans.(a)

Sol.

S8. Ans.(c)

Sol. ▭(Sag correction (Cs)=(W^2 L)/(24 pm^2 ))

W→ Total weight

Pm → Pull at the time of measurement

S9. Ans.(a)

Sol. The Green house gases as per their decreasing order of effectiveness are-

CO_2>CH_4>N_2 O>CFC.

S10. Ans.(c)

Sol. soil is partially saturated

Unit weight = 2g/cm³

G = 2.6

Moisture content (w) = 20%

Degree of saturation (S) = ?

r_d=r_b/((1+w) )=(Gr_w)/((1+e) )

2/(1+0.2)=(2.6×1)/(1+e)

▭(e=0.56)

Se=WG

S×0.56=0.2×2.6

▭(S=0.928=92.8%)