Abstract
This paper adopts laboratory test method in analyzing influence of the different kinds of chemical additives on early concrete shrinkage and cracking behaviors. The research results indicate that: tensile strength and compressive strength of concrete can all be promoted somewhat by adding chemical additive, expanding agent has the most obvious influence on strength and elastic modulus of concrete, the next is air entraining agent, and water reducing agent has the minimum influence on basic performance of concrete. According to the test results, mixing proportions of expanding agent, water reducing agent and air entraining agent are 8%, 1.5% and 0.4% respectively, and anti-shrinkage performance of the concrete is best in the early stage. When mixing expanding agent and water reducing agent in concrete simultaneously, anti-cracking effect of concrete shall be worse by comparing with that when adding only one chemical additive. In practical engineering application, the optimum chemical additive mixing proportion can be obtained in continuous tests.
