高性能混凝土收缩徐变性能的试验研究

Test Study of Shrinkage and Creep Behavior of High Performance Concrete

试验研究了水泥用量、矿物掺合料、龄期对高性能混凝土收缩、徐变的影响规律。试验结果表明:在胶凝材料用量一定、水胶比相近的情况下,水泥用量越低,矿渣掺量越大,混凝土的收缩、徐变值越小;在高性能混凝土中宜选用比表面积低于444 m2/kg的矿渣,且矿渣和粉煤灰总掺量宜大于40%;混凝土的收缩、徐变在加载后90 d内增长较大,在120 d后趋于稳定。

The laws of influences from usage amount of cement, mineral admixtures and concrete age on shrinkage and creep of high performance concrete are studied through tests. The resuits of the tests indicate that in the case of given amount of binding materials and approximate water/binding material ratio, the less amount of cement and greater amount of adding mineral slag are used, the smaller values of concrete shrinkage and creep will be. For high performance concrete, it is preferably to use mineral slag with specific surface area less than 444 m^2/kg, and the total adding amount of the slag and flyash should be greater than 40%. The shrinkage and creep of the concrete increase considerably 90 d after the concrete has been loaded, and tend to be stable after 120 d.