What Is Shotcrete? The concrete in which mortar or concrete is pneumatically projected at high velocity on the backup surface is known as shotcrete or gunite. It is also known as spray concrete as the force of jet impacting on the surface compacts it so as to make itself supporting. This type of concrete has … Read more
According to size the aggregates are classified as: Fine Aggregate Coarse Aggregate All in Aggregate Fine Aggregate It is the aggregate most of which passes 4.75 mm IS sieve and contains only so much coarser as is permitted by specification. According to source fine aggregate may be described as: Natural Sand– it is the aggregate … Read more
One of the first field investigations for a concrete construction project is to search for sources of aggregates which will give material of good quality at economical rates. Suitability of aggregate will depend upon the geological history of the region. The aggregate as per nature of formation may be divided into two types. Natural Aggregates … Read more
To describe an aggregate by its maximum and minimum size is not sufficient. It has to be graded from its minimum to maximum size. IS-383 recommends the following grading limit for fine aggregates. Grading Limits For Fine Aggregates Sieve Size Percentage of Passing For Grading Zone-I Grading Zone-II Grading Zone-III Grading Zone-IV 10 mm 100 … Read more
Advantages Of Concrete Curing Compound Following are the advantages claimed for the curing compounds It permits early curing as they can be applied within about half an hour of casting after the bleeding water has evaporated and the glossy shine or brightness of water has disappeared. They are applied in a single operation and one … Read more
What Is Guniting? The guniting is the most effective process of repairing concrete work which has been damaged due to inferior work or other reasons. It is also used for providing an impervious layer. The gunite is a mixture of cement and sand, the usual proportion being 1:3. A cement gun is used to deposit … Read more
It is advisable to use clean water fit for drinking purposes for making cement concrete. However, at places where sea water is available in abundance and potable water is costly, the sea water can be used for making cement concrete. The problem of using sea water for making cement concrete has to be studied from … Read more
Advantages of Slump Test It grants the facility to easily detect the difference in water content of successive batches of concrete of the same identical mix. The apparatus is cheap, portable and convenient to be used at site. Limitation of Slump Test As such, there is no direct relationship between the workability and the value … Read more
Aggregate Classification [Based on Shape] According to shape the aggregate is classified as Rounded aggregate Irregular or partly rounded aggregate Angular aggregate Flaky aggregate Elongated aggregate Flaky and elongated aggregate 1. Rounded Aggregate The aggregate with rounded shape has the minimum percentage of voids ranging from 32 to 33%. It gives minimum ratio of surface … Read more
Concrete is prepared by mixing aggregate, cement and water in such a proportion that it becomes workable in its plastic state and durable in its hardened state. Our aim is to satisfy both of these requirements i.e. workability and durability. Importance in terms of Workability A workable concrete can be achieved by adding more water, … Read more