Brick Manufacturing process Bricks are among the oldest and most enduring of mankind’s building materials. Bricks are made by shaping a plastic mass of clay and water, which is then hardened by drying and firing. Until comparatively recent times the clay was dug, the bricks were made and the kilns set or drawn by manual … Read more
Methods of Aggregate Sampling Due to the various sampling locations and the availability of equipment, there are several methods of taking aggregate samples. Uniformity of obtaining the sample cannot be emphasized enough, since it eliminates one variable in test results. The technician must remember that safety comes first. 1. PRODUCTION SAMPLING Bin Sample Sampling the … Read more
Aging of Bitumen Binders Bitumen, like any organic matter, is affected by factors like presence of oxygen, ultraviolet rays and changes in temperature. These factors are responsible for hardening of bitumen. Hardening results in Decrease in penetration value Increase in softening point temperature and Increase in penetration index (PI). For increased life of bituminous pavement … Read more
Quality Assurance for Cement Plastering Plastering is a process of applying one or more coats of mortar to a concrete surface, brickwork, stone masonry or lathing. It must be durable such that it resists the penetration of moisture and should be able to weather uniformly. It should also be pleasing in appearance. These properties depend … Read more
Factors influencing Corrosion of Reinforcement In reinforced cement concrete construction the corrosion of reinforcement takes place due to the presence of chlorides and sulphates beyond a critical limit and when sufficient alkalies is not obtained within the concrete to maintain steel in a positive condition. The following factors are responsible for corrosion of steel reinforcement … Read more
Bricks used in construction industry can have the following defects. So before using the bricks, it should be inspected properly for presence of any of the following defects. Different Types of Defects Found on Bricks 1. Over-burning of Bricks Bricks should be burned at temperatures at which incipient, complete and viscous vitrification occur. However, if … Read more
Aim This test method describes the procedure for determining the drying shrinkage or change in length of concrete specimen due to changes in moisture content. Apparatus A length measuring apparatus incorporating a dial gauge capable of measuring the length accurately to 0.005 mm. (see fig shown below) Drying oven capable of maintaining a temperature of … Read more
Properties of Fresh Concrete Concrete remains in its fresh state from the time it is mixed until it sets. During this time the concrete is handled, transported, placed and compacted. Properties of concrete in its fresh state are very important because the influence the quality of the hardened concrete. The fresh concrete has the following … Read more
QUALITY REQUIREMENTS OF COMMON BURNT CLAY BUILDING BRICKS 1. General Quality Bricks shall be free from cracks and flaws and nodules of free lime. Bricks shall have smooth rectangular faces with sharp corners Bricks shall be uniform in colour Frog size of a hand moulded brick having height of 90 mm or 70 mm shall … Read more
Retempering of Concrete When water is added to a stiffened concrete or partially set fresh concrete in order to bring it back to the desired consistency or workability, then it is called “retempering of concrete’. Importance of Retempering of Concrete The one and only reason for retempering of concrete is to regain the lost workability … Read more