Highway Engineering Multiple Choice Questions on “Design of Horizontal Alignment – 1”.
1. The degree if curve is central angle subtended by an arc of length is?
a) 20m
b) 25m
c) 30m
d) 35m
Answer: c
Clarification: The relation between degree and radius of circular curve is RDπ/180=30.
2. The ratio between centrifugal force and weight of the vehicle is called ___________
a) Impact factor
b) Impact ratio
c) Centrifugal factor
d) Centrifugal impulse
Answer: a
Clarification: The relationship between centrifugal force and weight of the vehicle is called impact factor or centrifugal ratio.
3. Which of the following is equal to super elevation?
a) Sinθ
b) Cosθ
c) Tanθ
d) Secθ
Answer: c
Clarification: The transverse inclination to the pavement surface is called as super elevation or cant banking which is equal to tanθ.
4. If the radius of a horizontal curve is 120m, then calculate the safe allowable speed.
a) 50kmph
b) 60kmph
c) 70kmph
d) 80kmph
Answer: b
Clarification: The safe allowable speed is Va = √(27.94R)
Va = √(27.94*120)
Va = 60kmph.
5. If the super elevation of the highway provided is zero, then the design speed of highway having a curve of 200m and coefficient of friction 0.10 is?
a) 40kmph
b) 50kmph
c) 55kmph
d) 60kmph
Answer: b
Clarification: The design velocity is given by V=√127Rf
V=√127×200×0.1
V=50Kmph.
6. The design speed on a highway is 60kmph; calculate the super elevation if radius of curve is 150m and coefficient of friction is 0.15.
a) 0.07
b) 0.038
c) 0.04
d) 0.15
Answer: b
Clarification: e+f=v2/127R
e+f=3600/(127*150)
e+f=0.188
e=0.188-0.15
e=0.038.
7. The super elevation is calculated for ___________
a) 75% of design speed including friction
b) 80% of design speed neglecting friction
c) 75% of design speed neglecting friction
d) 80% of design speed including friction
Answer: c
Clarification: The super elevation is calculated for 75% of design speed neglecting the friction on the pavement.
8. If the super elevation is 0.07 and width of pavement is 7m then the raise of outer edge with respect to inner edge is ___________
a) 0.47m
b) 0.48m
c) 0.49m
d) 0.50m
Answer: c
Clarification: The raise of outer edge is given by
E=Be,
E=7*0.07=0.49m
9. The ruling minimum radius in the curve is given by ___________
a) R=V2/127(e+f)
b) R=V’2/127 (e+f)
c) R=127(e+f)
d) R=127/(e+f)
Answer: b
Clarification: The ruling minimum radius is calculated by using the minimum design speed provided by IRC.
10. The extra widening is the sum of ___________
a) Mechanical widening and psychological widening
b) Two times of mechanical widening
c) Two times of psychological widening
d) Mechanical widening – physical widening
Answer: a
Clarification: The extra widening is the sum of mechanical widening and physiological widening, the mechanical widening is done for the safety of vehicles and psychological widening is done for the comfort of passengers.