纤维种类与掺量对UHPFRC力学性能的影响

Influence of Fiber Types and Dosages on Mechanical Properties of UHPFRC

以纤维种类与掺量为变量分组,按照流程进行超高性能纤维增强混凝土(UHPFRC)的制作和养护,使用微机控制全自动恒加载压力试验机等测得UHPFRC的抗折强度和抗压强度,从而研究纤维种类与掺量对UHPFRC力学性能的影响。结果表明:随着纤维掺量从零开始不断增加,UHPFRC的抗压强度和抗折强度出现先增加后降低的规律;当掺入X纤维和J纤维的质量分数达到0.3%时,UHPFRC抗压强度达到最大值;当掺入X纤维的质量分数达到0.4%、掺入J纤维的质量分数达到0.3%时,UHPFRC抗折强度达到最大值;在相同纤维掺量情况下,X纤维增强抗压强度效益总体优于J纤维,X纤维增强抗折强度效益全面优于J纤维。

This study grouped variables by fiber types and dosages,and followed the process for making and curing ultra-high performance fiber reinforced concrete(UHPFRC).Using a microcomputer-controlled automatic constant-load pressure testing machine,the flexural strength and compressive strength of UHPFRC were measured to investigate the impact of fiber types and dosages on the mechanical properties of UHPFRC.The results show that as the fiber dosage increases from zero,both the compressive strength and flexural strength of UHPFRC first increase and then decrease.The maximum compressive strength of UHPFRC is achieved when the mass fraction of fibers X and J reaches 0.3%;the maximum flexural strength is reached when the mass fraction of fiber X is 0.4% and that of fiber J is 0.3%.Under the same fiber dosage,the compressive strength enhancement by fiber X is generally superior to that by fiber J,and the enhancement of flexural strength by fiber X is comprehensively better than that by fiber J.