Technical Drawing - Exam Papers - Ordinary - 1994 - Building

Question 4

Fig. 4 shows the outline plan of four adjoining hyperbolic roof surfaces ABOH, BCDO, DEFO, and FGHO. The roof perimeter is a square in plan.
The corners A, C, E and G are 7m above ground level, corners B, D, F and H are at ground level and corner O is 16m above ground level.

(a) Draw the plan of the roof and project the elevation.
(b) Show the curvature of the roof along a line joining B and E.
(c) Draw a new elevation of the roof in which the true length of edge AB will be seen.

Scale 1: 200