TRANSPORTATION ENGINEERING MCQs 1  CIVIL ENGINEERING  GATE EXAM
1. The important factor considered in the
design of summit curves on highways is __. 
A. comfort to passenger 
B. superelevation

C. sight distance 
D. impact factor 
Answer: C sight distance Explanation: When
a fastmoving vehicle travels along a summit curve, the centrifugal force
will act upward, against gravity, which relieves some of the pressure on the
tyres and suspension springs of the vehicle. Thus,
there is no issue with passengers feeling uncomfortable when riding on summit
curves. The provision of sufficient sight distance is the only challenge in
constructing summit curves. Every
portion of the road system, as well as summit curves, should always have the
stopping sight distance or the absolute minimum sight distance. 
2. The ideal form of curve for the summit
curve is ____. 
A. lemniscate 
B. circular 
C. spiral 
D. parabola 
Answer: B circular Explanation: The
sight distance is constant throughout the length of the circular summit
curve. In practice, we employ square parabolic curves since they are simple
to compute and provide comfortable riding. 
3.
Transition curves are provided on the approach to horizontal curves in order
to __. 
A. reduce jerk to allowable
levels 
B. increase jerk to allowable
levels 
C. minimize the length of the
horizontal curve 
D. simplify the laying out and
construction of the horizontal curve 
Answer: A reduce jerk to allowable levels Explanation: The
radius of the transition curve reduces from infinity at the point of
intersection to the desired radius of the circular curve. A automobile
travelling on a straight road that curves at a radius of R experiences a
sharp jerk due to the centrifugal force that suddenly acts on the vehicle
just after the tangent point. In
addition to making the passengers uncomfortable, this makes it impossible to
drive the vehicle safely. The
centrifugal force will gradually appear if a transition curve is added
between a straight and circular curve of radius "R," as the radius
of the transition curve decreases from infinity. The
rate at which this force is introduced can be controlled by adopting suitable
shape of the transition curve and by designing its length so that vehicle can
have a smooth entry from the straight to the circular curve at the design
speed. 
4.
On sag (or valley) curves the available sight distance is determined based on
___. 
A. height of headlight 
B. height of driver’s eye 
C. height of obstacle 
D. design speed 
Answer: A height of
headlight 
5.
At highway stretches where the
required overtaking sight distance cannot be provided, it is necessary to
incorporate in such sections the following ___. 
A. one third of the required
overtaking sight distance 
B. at least twice the stopping
sight distance 
C. three times the stopping sight
distance 
D. half of the required
overtaking sight distance 
Answer: B at least twice
the stopping sight distance Explanation: Intermediate
Sight Distance ISD = 2 * SSD Minimum
length of overtaking zone = 3 * OSD Desirable
length of overtaking zone = 5 * OSD 
Comments
Post a Comment