Technical Drawing - Exam Papers - Ordinary - 1998 - Building

Question 4

Fig. 4 shows the outline plan of a hyperbolic paraboloid roof surface. The roof perimeter is a square in plan. The corners A and C are at ground level, corner B is 8 m above ground level and corner D is 22 m above ground level.

(a) Draw the plan of the roof and project the elevation.
(b) Determine the true shape of the section S-S through the roof.
(c) Draw an elevation of the roof in which the true length of the edge AB will be seen.

Scale 1 : 200