高性能轻集料混凝土收缩性能研究

试验研究了胶凝材料用量、砂率、矿物掺合料和引气剂掺量对高性能轻集料混凝土收缩性能的影响。结果表明,高性能轻集料混凝土的收缩早期增长较快,到45d后增长才逐渐减缓,其达到稳定所需时间较长。轻集料混凝土的收缩随着胶凝材料的增加、水胶比和砂率的降低而增大;掺入一定量的粉煤灰和矿渣可以明显减小轻集料混凝土的收缩变形;引气剂的掺量对轻集料混凝土早期收缩影响不大,但混凝土后期收缩随引气剂掺量的增加而有不同程度的增大。

Study on Shrinkage of High Performance Lightweight Aggregate Concrete

The influences of contents of binders,volumatric percentage of sand,mineral admixtures and air-entrainers on the shrinkage of high performance lightweight aggregate concrete(HPLC) are studied by tests.The experimental results indicate that the shrinkage of high performance lightweight aggregate concrete is increased quickly at early stage and it slows down to the even after 45days or more longer age.Furthermore,the shrinkage of HPLC increases when the content of binder is increased,or water binder ratio and sand percentage are decreased.Fly-ash and blast-furnaced slag can decrease the shrinkage of concrete.The effect of air-entrainer on the shrinkage of HPLC is limited at early stage.However,at the late-stage it grows at different level with increasing of air-entrainer content.