The Asian Review of Civil Engineering (TARCE) is a half-yearly international peer-reviewed journal of Civil Engineering. One of the objectives of this journal is to disseminate knowledge on various research issues connected with the topics include, but are not limited to:

Coastal engineering
Construction engineering
Earthquake engineering
Environmental engineering
Geotechnical engineering
Water resources engineering
Materials engineering
Structural engineering
Surveying
Transportation engineering
Municipal or urban engineering

As the grade of concrete is increases the quantity of cement is increases which effects on theproperties of retempered concrete. For M20 concrete we can retemper the concrete upto 120 min. but forM40 concrete retempering time is only 30 min. Adding water to a plastic mix to increase slump is an extremely common practice, even though it is not recommended because it increases the porosity of concrete. Concrete often arrives on site more than half an hour after initial mixing. Placement operations can take anywhere from 10 to 60 minutes, depending on the field conditions and the size of the load. When the slump decreases to an unacceptable level during the operations, water is added to the mix. Objective of this paper to study the strength characteristics of retempered concrete M20 & M40 concrete. Usually the retempering process is used with normal concrete or with ready mixed concrete; an attempt is made to check the compressive and flexural strength of normal retempered concrete with an addition of retarder in three different percentages as 0.2%, 0.4% and 0.6% at retempering time of 15 minutes to 90 minutes.