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
Non-Destructive Testing of Concrete (NDT on Concrete) Non destructive test is a method of testing existing concrete structures to assess the strength and durability of concrete structure. In the non destructive method of testing, without loading the specimen to failure (i.e. without destructing the concrete) we can measure strength of concrete. Now days this method … Read more
Self Compacting Concrete (SCC) The term SCC in concrete technology means self compacting concrete. In this type of concrete you do not need to use any kind of vibrator to compact it and still you can achieve a concrete which is better and more reliable and uniform in quality and having high degree of performance. … Read more
Causes of Cracks in Concrete and its Remedies Cracks in concrete are caused due to following factors. One of the main causes of cracks in concrete is the cooling and contraction due to setting of concrete. Volume change and stresses due to shrinkage are independent of any external load or stress applied. Cracks may develop … Read more
Carbonation of Concrete Carbonation of concrete is one of the reasons for corrosion of reinforcement. It is a process by which carbon dioxide from air penetrates into the concrete and reacts with calcium hydroxide to form calcium carbonates. The percentage of CO2 present is air vary from place to place. In case of rural areas … Read more
For the same strength or workability, concrete with large size aggregate will require lesser quantity of cement than concrete with a smaller size aggregate. In a mass concrete work the use of larger size aggregate will be useful due to the lesser consumption of cement. This will also reduce the heat of hydration and the … Read more
Prestressed Concrete Prestressed concrete is a modified form of reinforced concrete. it not only eliminates the weakness of concrete, but also makes it possible to take full advantage of compressive strength of concrete. The term “Prestressed Concrete” is applied to those reinforced concrete members in which concrete is subjected to compressive stresses, before the external … Read more
Points to Consider Mixing of mineral admixtures with OPC at site should not normally be permitted. However for projects requiring use of blended cement from durability and strength considerations, which is not available from the cement manufacturer blending may be permitted through a specific facility created at site with complete automated process control to achieve … Read more
Finishing may be defined as the process of leveling, smoothing, compacting and otherwise treating surface of fresh concrete or recently placed concrete to produce desired appearance. Steps Involved for Finishing Concrete There are 3 different steps involved for finishing concrete, which are as given below. Screeding Floating Trowelling 1. Screeding (Step-1) This is the process … Read more
Removal of Forms Forms should not be removed until the concrete has sufficiently hardened in order that it can carry safely its own weight and any other live loads it is subjected to. The supporting period (period between placing of concrete in forms and removal of forms) differ according to the type of cement used … Read more