Most candidates were able to:
state the reasons for introducing steel reinforcement in a concrete lintel;
list the operations involved in concrete work;
state the mix proportion commonly used for the given types of concrete.
However, majority of the candidates were unable to state the type of mechanical plant
most suitable for each of the given building construction operations.
The expected response to question 1 is as given below:
(a)(i)To take care of tensile stresses.
(ii) To provide for anchorage.
(iii) To take care of shear stresses.
(iv)To provide for rigidity.
(b)(i) Batching
(ii) Mixing
(iii)Placing
(iv) Compaction
(v) Curing
(vi) Transporting
(vii) Protection against damage
(c)
(i) For mass concrete: 1 : 3 : 6
(ii) For reinforced concrete: 1: 2 : 4
(iii) Blinding 1 : 4: 8
(d) (i) Site clearance - bulldozer or skimmer
(ii) Excavation of trenches-trencher
(iii)Pit excavation - backactor
(iv) Digging, transporting and dumping of the loose soil - scrapper or skimmer |