Civil Engineering - GATE Exam Questions - Discussion

Here according to me spiral curve because rate of according of centrifugal force is constant. This case not satisfied in parabola, lemniscate.

I think circular curve is the right answer.

From sight distance criteria, circular curve is the right answer.

Many curve forms can be used with satisfactory results, the common practice has been to use parabolic curves in summit curves. This is primarily because of the ease with it can be laid out as well as allowing a comfortable transition from one gradient to another. Although a circular curve offers equal sight distance at every point on the curve, for very small deviation angles a circular curve and parabolic curves are almost congruent. Furthermore, the use of parabolic curves were found to give excellent riding comfort.

Ideal curve is circular and most preferred curve is parabola.

I think it is circular curve.

Which one is right circular or parabola?

I think it is spiral.

The circular curve is the ideal form of summit curve because of in circular summit curve sight distance available throughout the length of the circular curve is constant.

But in practice, generally, use square parabolic curve because it is easy to compute and also give riding comfort.

I think spiral is the correct answer.