天津高银117大厦C70大体积自密实混凝土耐久性能研究

Study on Durability of C70 Mass Self-compacting Concrete of Tianjin Gaoyin 117 Building

对基于强度和工作性优选出的3个配合比进行净浆水化温升和耐久性研究,确定大体积自密实混凝土的最佳配合比,并应用于工程中。其中,最佳配合比混凝土的抗冻性达到F200,6h电通量低于165C,21d收缩率为0.03%,其净浆的放热速率和放热峰值均低于其他配合比;说明适量微珠的掺入不仅改善了混凝土的工作性能和耐久性,也有利于控制大体积混凝土前期浇筑时产生的水化热。

The hydration temperature rise and durability of paste with three mix proportion based on strength and workability was researched, which was used for determining the best mix proportion of mass self-compacting concrete. The frost resistance of the best ratio of concrete can reach F200, the electric flux is lower than 165C, shrinkage of 21 day is 0.03% , and the heat release rate and exothermic peak of the paste are lower than that with other mix proportion. It means that the incorporation of microspheres can improve the performance and durability of concrete, and is propitious to control the heat of hydration on the prophase of concrete pouring.