粗集料堆叠率对自密实混凝土性能的影响

摘要

Studied the influences of gradation and packing ratio of coarse aggregate on the fluidity,passing abillity through gaps,filling performance and mechanical properties of self-compacting concrete( SCC)by using three coarse aggregate grading and packing ratios (0.5,0.6,0.7).The result indicates that the workability of SCC would be worse with increase of parking ratio and increase of the mean particle size of coarse aggregate. However,the mechanical strength of SCC would increase with parking ratio of coarse aggregate and mean size of the coarse aggregate. Obviously there is a contrary influence between the content of coarse aggregate and the particle grada-tion of it on the workability and the strengths. Therefore to meet an appropriate workability of SCC,increase on coarse aggregate content and mean size of coarse aggregate gradation will contribute to the strength of SCC.%研究了自密实混凝土中粗集料的堆叠率和级配对自密实混凝土流动性、间隙通过性、填充性能和强度的影响。研究表明：随着粗集料堆叠率的增大，自密实混凝土的各种工作性会逐渐变差，随着级配的细化自密实混凝土工作性则改善，但混凝土强度则会随着堆叠率的增大而增大，随级配的细化强度则降低。由此可见，在粗集料用量和级配设计方面，工作性和强度之间存在对立关系，在满足自密实混凝土工作性的前提下尽可能增加粗集料用量，采用较粗的级配有利于力学性能的提高。