PROPERTIES OF AGGREGATES FOR CONCRETE

Properties of Aggregates Approximately 75% of the volume of concrete is occupied by aggregates, so quality of aggregates plays an important role in determining properties of concrete.  Aggregates are chemically inert, solid bodies held together by the cement. Aggregates come in various shapes, sizes, and materials ranging from fine particles of sand to large, coarse … Read more

FIRE RESISTING PROPERTIES OF COMMON BUILDING MATERIALS

Fire resisting properties of common construction material-min

FIRE RESISTING PROPERTIES OF COMMON BUILDING MTERIALS Fire resisting properties of common building materials such as stone, brick, timber, cast-iron, glass, steel and concrete are mentioned below. 1. STONE The stone is a bad conductor of heat. But it suffers appreciably under the effects of fire. The stone is also liable to disintegrate into small … Read more

5 FACTORS CAUSING DISINTEGRATION OF CONCRETE

DISINTEGRATION OF CONCRETE

CAUSES OF DISINTEGRATION OF CONCRETE The primary reasons that cause disintegration of concrete member are desribed below. 1. SULPHATE ATTACK Soluble sulphates are present in Ground water Soil Clay bricks Soluble sulphates react with Tricalcium Aluminate of cement I n the presence of moisture and form products which occupy much bigger volume than that of … Read more

HOW TO MINIMISE THE DEFECTS IN PLASTERING WORK?

plastering

Minimising Defects in Plastering Work Defects in plastering work can be minimised by following the below mentioned techniques. The brick and plastering work should be carried out by skilled masons in the best workmanship manner. Bond of brick work should be properly maintained. Efflorescence is removed by rubbing brushes on the damaged surface. A solution … Read more

4 PRIMARY CEMENT COMPOUNDS & THEIR ROLES

cement compounds

Compounds of Cement About 90-95% of a Portland cement is comprised of the four main cement minerals, which are C3S, C2S, C3A, and C4AF, with the remainder consisting of calcium sulphate, alkali sulphates, unreacted (free) CaO, MgO, and other minor constituents left over from the clinkering and grinding steps. The four cement minerals play very different … Read more

8 PRIMARY REQUIREMENTS OF FORMWORK

REQUIREMENTS OF FORMWORK

REQUIREMENTS OF FORMWORK – QUALITY, SAFETY & ECONOMY In the selection of materials for formwork, the three general principles of quality, safety and economy must be paramount. Material quality can ensure safety, and significantly contributes to the achievement of economy. Formwork failure can result in loss of life and always causes catastrophic financial loss. Some … Read more

6 IMPORTANT ENGINEERING PROPERTIES OF MORTAR

properties of mortar

Properties of Mortar Properties of mortar which are sought for use in masonry are: workability, water retentivity, rate of stiffening, strength, resistance to rain penetration and durability. These properties have been discussed below explaining their effect on masonry. Choice of masonry mortar is governed by several considerations such as Type of masonry unit and its … Read more