Aggregate is small pieces of stones or sand in concrete. There are many kinds of aggregates used
in concrete, such as light weight aggregate, aggregates for fire resistance, for thermal insulation,
and for radiation protection, etc.
3.1 What is free-body diagram (FBD)
A body or a structure may subject to variety of forces, such as selfweight, load carried by the body, force from support to the body, and so
on. Block A in Fig. 3.1.1, for example, subjects
What is Cement?
A powdery material that, when mixed with water, react chemically with the water and
gradually form a strong solid. The mixture of cement and water is termed cement paste.
Traditionally concrete is a mixture of aggregate
Timber is one of the earliest materials used in construction and still plays an important role in
modern construction industry. In Hong Kong, timber is mainly used for temporary work, such
as formwork. In USA, Canada, Japan and Northern European co
Concepts of forces
A force is a 'push' or a 'pull' exerted by one body on another.
A force can be exerted through direct contact between bodies, such as a
person pulling on a rope, or it can occur when the bodies are physically
Traditionally, concrete mix consists mainly of cement, coarse and fine aggregate mixed and
water. Concrete is designed to meet functional requirements, such as, strength, durability, fire
protection, sound and thermal insulation. The
Brick, Block & Masonry Mortars and Bituminous Materials
What is Brick?
A rectangular block for construction purpose with dimensions no larger than 337.5 x
225 x 112.5 mm as according to BS 3921. The most widely used size is 215 x 102.5 x
65 mm. The bricks
CONSTRUCTION MATERIALS - GLASS
Glass is a uniform material, a solidified liquid. The molecules are in completely random order
and do not form a crystal lattice. This is why glass is transparent. As it consists of
combination of various bon
Paint is a coating on a surface of a material (substrate). Usually, when paint is applied to a
substrate, it is in a liquid form. After application as a thin layer, it is converted to a solid film.
This process is known as drying or curing. Paint is
ALKALI AGGREGATE REACTION IN CONCRETE (AAR)
1. Neville A et al "Concrete Technology", revised reprint 1990, Longman Scientific
and Technical. (The following section may be particularly relevant: Basic
chemistry of cement, Hydration of cemen