Section A
Q1.
(a) The images X and Y of the base and the top respectively of a tower having height 155 m are observed in a truly vertical aerial photograph of scale 1 : 10,000. Determine the position of X from the principal point given that Y is 75.0 mm from the principal point of the photograph. Focal length of the aerial camera is 125 mm. Assume the tower to be at the datum level.
(b)
Calculate the maximum permissible speed on a curve of a high speed broad gauge track of group A using the following data :
(i) Degree of curve = 2\circ
(ii) Superelevation = 85 mm
(iii) Length of transition curve = 125 m
(iv) Maximum sanctioned speed = 160 km/h
(v) Cant deficiency = 100 mm
(c) Determine the safe stopping sight distance to avoid head-on collision for two cars A and B that are approaching towards each other from opposite directions. Car A is moving at a speed of 85 km/h in upward direction and car B is moving at a speed of 65 km/h in downward direction. Assume reaction time as 2.5 seconds, coefficient of friction as 0.37 and a brake efficiency as 80%. The gradient of road section is taken as 2%.
(d) Briefly explain how Total float and Free float can be determined. In a network analysis, how can total float be used to determine critical path and subcritical path ?
(e)
Answer the following in brief:
(i) What is the basic advantage of using ferro-cement in ferro-cement concrete?
(ii) Why is carbon fiber reinforced polymer used for seismic retrofitting and repair of damaged structures ?
