Observation

Majority of the candidates were able to:

•  state three desirable properties of hardened concrete.
• state three functions of an internal wall.

However, majority of them failed to explain the reasons for providing a landing in a stair construction.
The expected response to question 3 is as given below:
(a) Desirable properties of hardened concrete:

• should be  durable;
• should be  of the required strength;
• should be  of the correct density;
• should be  impermeable to water;
• should be  resistant to friction;
• should be  free from shrinkage cracks;
• should be able to withstand fire;
• should resist indentation.

(b)        Functions of an internal wall:

• to assist in carrying the loads imposed on the structure;
• to divide space;
• to provide sound  insulation;
• to resist the spread of fire;
• to provide security;
• to support fixtures, fittings and decorations;
• to accommodate services.

(c)        Reason for providing landing in a stair construction:
-           to allow for change of direction;
-           to provide an access for rest.
-           to limit the distance someone is likely to fall.
-           to break up the span.
-           to permit safe passage on the flight of stairs.