混凝土收缩与环境湿度的关系研究

Experimental Study on Relationship between Shrinkage Strain and Environmental Humidity of Concrete

为探索环境湿度对混凝土收缩性能的影响,选取了典型的C30和C70混凝土,通过采用饱和盐溶液方法形成不同的相对湿度环境,研究了混凝土干缩值与环境相对湿度之间的关系.结果表明,混凝土的干缩受环境相对湿度影响显著,环境相对湿度越低,其干缩值越大,但混凝土干缩值与环境相对湿度之间的关系不能用简单的线性关系来描述.另外,普通(C30)与高强(C70)混凝土的干缩值与环境相对湿度之间的关系不同.

Shrinkage of concrete is one of the principle reasons leading the formation of cracks in concrete structures. In this paper, the effect of environmental humidity on the shrinkage strain in concrete is presented. The different environmental humidities are created by using different saline solution. Two kinds of concretes with compressive strength 40 MPa （C30） and 80 MPa （C70） respectively were used in the tests. The experimental results show that the environmental humidity can significantly influence the shrinkage strain in concrete. The relationship between shrinkage and environmental humidity can not be expressed by a simple linear relation.