玄武岩纤维与粉煤灰协同作用对火山渣轻集料混凝土性能的影响

研究了玄武岩纤维单掺、玄武岩纤维与粉煤灰复掺对火山渣轻集料混凝土工作性能、力学性能及其抗冻性能的影响规律,结果表明:单掺玄武岩纤维能改善火山渣轻集料混凝土粗骨料上浮和分层离析的缺陷,但会导致坍落度降低;在标准养护条件下能显著提高火山渣轻集料混凝土早期强度,但后期增强效果不佳。当玄武岩纤维与粉煤灰复掺时,粉煤灰的形态效应可提高玄武岩增强火山渣轻集料混凝土的流动性,延长了玄武岩纤维对火山渣轻集料混凝土后期力学性能的增强时效;通过XRD分析、XRF分析和SEM微观分析表明:粉煤灰的掺入可降低水泥基体中Ca(OH)_2含量和对玄武岩纤维的碱腐蚀程度,加上粉煤灰自身后期的二次水化,改善了水泥基体的界面性质,大大提高了火山渣轻集料混凝土的后期强度和抗冻性。

Effect of synergistic effect of basalt fiber and fly ash on properties of volcanic slag lightw eight aggregate concrete

The effects of basalt fiber alone,basalt fiber and fly ash admixture on the performance of volcanic slag light aggregate concrete,mechanical properties and frost resistance were studied.The results show that incorporation of basalt fiber can properly improve the light aggregate concrete coarse aggregate flotation and delamination segregation defects,but will lead to slump,and can significantly improve the early strength of volcanic slag light aggregate concrete under standard curing conditions,but the late enhancement decreased.When the basalt fiber and fly ash complex doped,the morphological effects of fly ash can enhance the mobility of basalt reinforced volcanic slag lightweight aggregate concrete,The results of XRD,XRF and SEM show that the incorporation of fly ash can reduce the content of Ca(OH)2 in the cement matrix and the alkali corrosion of basalt fiber,and prolong the effect of basalt fiber on volcanic slag light aggregate The enhanced aging of the mechanical properties of the concrete in the late stage and the secondary hydration of fly ash itself later improve the interfacial properties of the cement matrix and greatly improve the post strength and frost resistance of volcanic slag lightweight aggregate.