**Quiz: Civil EngineeringExam: THDC-Junior Engineer TraineeTopic: Miscellaneous**

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

Q1. The correct relationship between theoretical oxygen demand (TOD), biochemical oxygen demand (BOD) and, chemical oxygen demand (COD) is given by.

(a) TOD > BOD > COD

(b) BOD > COD > TOD

(c) COD > BOD > TOD

(d) TOD > COD > BOD

Q2. The ordinate of the instantaneous Unit Hydrograph (IUH) of a catchment at any time t, is

(a) the slope of the 1 hour unit hydrograph at that time

(b) the slope of the direct runoff unit hydrograph at that time

(c) difference in the slope of the S curve and 1 hour unit hydrograph

(d) the slope of the S curve with effective rainfall intensity of 1 cm/hr

Q3. What will be the shift of transition curve, if the length of transition curve is 80 m. and radius of the curve is 320 m?

(a) 0.011

(b) 0.83

(c) 0.89

(d) 21.33

Q4. The mean velocity in open channels can be estimated from the known velocity at the free surface. It is appx equal to:

(a) 0.88

(b) 1.1

(c) 0.75

(d) 0.65

Q5. What is the minimum value of test results (in N/mm²) for compressive strength compliance requirement for concrete M 20 as per codal provision?

(a) f_ck-1

(b) f_ck-5

(c) f_ck-3

(d) f_ck-4

Q6. In case of a direct Vernier scale–

(a) Smallest division is longer than smallest division of the main scale 1.

(b) Graduations increase in the same direction in which graduations of the main scale increases

(c) Graduations increase in opposite direction in which graduations of the main scale increase

(d) None of these

Q7. A soil has plastic limit of 20% and plasticity index of 40%. If the natural water content of the soil is 34%, then the consistency index is equal to

(a) 0.35

(b) 0.65

(c) 0.82

(d) 1.00

Q8. The ratio of shearing stress to shearing strain within elastic limit, is known as

(a) modulus of elasticity

(b) shear modulus of elasticity

(c) bulk modulus of elasticity

(d) tangent modulus of elasticity

Q9. The clear distance between the lateral restraints for a simply supported or continuous beam to ensure lateral stability should not exceed:

(a) 60 b² or 250 b²/d whichever is more.

(b) 60 b or 250 b²/ b whichever is less.

(c) 60 b or 250 b²/d whichever is more.

(d) 60 b or 250 b²/d whichever is less.

Q10. Minimum pitch of the rivets shall not be less than:

(a) 2.0d

(b) 1.5d

(c) 2.5d

(d) 3.0d

Solutions

S1. Ans.(d)

Sol. The correct relationship between TOD, COD and BOD is

▭(TOD>COD>BOD)

S2. Ans.(d)

Sol. The ordinate of one Instantaneous unit hydrograph at any time ‘t’ is the slope of s – curve of intensity 1 cm/hr.

S3. Ans.(b)

Sol. Given,

Length of transition curve (L_s) = 80 m

Radius of the curve (R) = 320 m

Shift(s) = (L_s^2)/24R

=(80)^2/(24×320)

= 0.83 m

S4. Ans. (a)

Sol. In open channel flow if free surface velocity is known then the mean velocity in open channel approximately 0.88 times the surface velocity.

S5. Ans.(d)

Sol. As per IS : 456 – 2000, the characteristic compressive strength compliance requirement are-

Grade of Concrete | Individual test results (in N/mm²) |

M 15 | ≥ f_ck – 3 |

M 20 or above | ≥ f_ck – 4 |

f_ck = Characteristic strength of concrete.

S6. Ans.(b)

Sol. In case of direct Vernier, graduation increase in the same direction in which graduations of the main scale increases.

S7. Ans.(b)

Sol. Given,

W_P=20%

W_n=34%

I_P=40 %

I_C= ?

I_c=(W_L-W_n)/(W_L-W_P )=(W_L-W_n)/I_P

Here,

I_P=40%

W_L-W_P=40%

W_L-20%=40%

W_L=60%

Now,

I_C=(60%-34%)/40

▭(I_C=0.65)

S8. Ans.(b)

Sol. ▭(Shear modulus of elasticity (G)=(Shear stress (τ))/(shear strain(ϕ) ))

S9. Ans.(d)

Sol. → For simply supported or continues beam the clear distance between lateral restrain should not exceed

60b (or) (250 b^2)/d.

→ For cantilever beam.

25b (or) (100 b^2)/d.

S10. Ans.(c)

Sol. minimum pitch of rivets should be 2.5 times the nominal diameter or rivet i.e. 2.5d.

d = nominal diameter of rivet.