矿物掺合料对高性能混凝土塑性收缩裂缝的影响

摘要

采用四周约束平板法测试系统，研究了粉煤灰、矿渣及硅灰不同掺量比对高性能混凝土早期塑性开裂的影响，同时对其开裂机理进行了研究探讨。试验结果表明：粉煤灰和矿渣的掺入对混凝土早期塑性开裂均有很好的抑制作用，粉煤灰的抑制效果要优于矿渣；硅灰的掺入加剧了混凝土的早期塑性开裂，并随着掺量的增加开裂愈加明显。%In order to study the influence of the content of fly ash,slag and silica fume on the early-age plastic shrinkage crack of the high performance concrete,this paper adopted the constraints in the plate method.Mean-while,the early-age plastic shrinkage crack mechanism of concrete was analyzed.The results show that the in-corporation of fly ash and slag on the early-age concrete plastic cracking are good inhibitory effect,and fly ash is superior to the inhibitory effect of slag.Silica fume could increase the early-age plastic cracking of concrete, and with the increase of dosage,cracking is becoming ever more obvious.