Most candidates were able to explain the:
- term curing in relation to concrete production;
- given terms used in setting out operation.
However, some were unable to:
- describe the methods of curing concrete;
- sketch a cross-section through a raft foundation.
The expected response to question 1 is as given below:
1(a) (i) Curing is a method of preventing rapid drying of moisture in concrete
or the process of retaining the moisture in a concrete mix during hydration of cement to enable it gain the desired strength.
(ii) Methods of curing concrete are:
- By spraying the surface with a curing agent.
- By placing wet sack over the surface.
- By using plastic sheeting or water proof paper to cover the freshly placed concrete.
- By covering the surface with clean damp sand.
- By flooding the surface with water.
Explanation of terms
b(i) The bench mark is an established level where all other levels are determined.
(ii) Datum level: - This is the reference level from which other levels on the site are determined.
(c) Cross section through a raft foundation