Observation

Most candidates were able to state two properties of hardened concrete. However, few of them failed to:

• explain the difference between English bond and Flemish bond in wall construction;
• sketch the elevation of a block wall in five courses high and indicate toothing and racking back.

  The expected response to question 3 is as given below:
  3     (a) Properties of hardened concrete:
Hardened concrete should:-

• be hard;
• be durable;
• have sufficient strength;
• be dense; 
• be impermeable to water;
• be resistant to fire;
• be resistant to stresses;
• be resistant to wearing;
• be resistant to friction/vibration;
• be capable of carrying loads.
(b) Difference between English bond and Flemish bond:

• English bond is a type of bonding brickwall in alternate courses of headers and stretchers.
• It consists of stretchers throughout the length of one course and headers throughout the length of next course.
•  It is much stronger than Flemish bond.
• Flemish bond is a type of bonding brickwall in alternate headers and stretchers in the same course. 
• Flemish bond gives more attractive face appearance.
(c) Elevation of a blockwall.