机制砂特性对高强混凝土流变性能的影响

Effect of machine-made sand characteristics on rheology of high strength concrete

伴随天然砂资源逐步短缺,应用机制砂替代天然砂并开展机制砂高强混凝土研究势在必行。同时,煤矿冻结井冲积层厚度不断增加,井壁混凝土强度逐渐提高至C80及更高。本文针对煤矿冻结井筒用高强高性能机制砂混凝土粘度大的问题,从机制砂母岩岩性、颗粒特性、石粉含量及MB值等特性对高强混凝土流变性能及工作原理进行研究,为解决冻结井混凝土井壁设计和施工应用难题提供参考。

With the gradual shortage of natural sand resources,it is imperative to replace natural sand with machinemade sand and carry out research on high-strength concrete with machine-made sand.At the same time,the thickness of alluvium of freezing shaft of coal mine increases,and the strength of shaft wall concrete is gradually increased to C80 and higher.This paper focuses on the problem of high viscosity of high-strength machine-made sand concrete used for freezing shaft of coal mine.The rheological properties and working principles of high-strength concrete are studied from the characteristics of parent rock lithology,particle characteristics,stone powder content and MB value of machine-made sand,providing reference to solve the problems in design and construction application of freezing shaft concrete walls.