【作者】 常钧； 崔凯；

【Author】 CHANG Jun;CUI Kai;School of Civil Engineering,Dalian University of Technology;

【机构】 大连理工大学土木工程学院；

【摘要】 本文对钢纤维增强活性粉混凝土(RPC)的力学性能进行了试验研究。本研究采用两种不同尺度,不同掺量的钢纤维,三种水灰比(0.22、0.24、0.26)、不同养护时间对RPC的影响。研究了混凝土的抗压和抗弯强度、荷载-挠度曲线、强度比、韧性指数和开裂性能等方面的性能。实验结果表明,随着钢纤维体积分数的增加,RPC的抗压强度、抗弯强度和抗弯韧性均有所提高,同时,由于混杂纤维的协同作用,RPC的抗弯韧性随体积分数的增加而显著提高。RPC中微钢纤维的临界长度小于实际长度,导致了RPC的断裂和能量的消耗,这从SEM中可以看出。此外,本文还揭示了纤维对RPC的增强机理,包括锚固作用、网络作用、桥接作用、界面作用、剥落作用和扭曲作用。更多还原

【Abstract】 This paper presents an experimental investigation on the mechanical behavior of hybrid steel fibers reinforced reactive powder concrete(HSRPC).In this study,two types of steel fibers with different contents,macro and micro straight were used,three water-to-cement ratios(0.22,0.24,0.26),varying curing ages was investigated on RPC.The compressive and flexural strength,the flexural behavior in terms of load-deflection curves,strength ratio and toughness index and cracking behavior was studied.Experimental results indicated that compressive,flexural strength and flexural toughness increased with the increasing volume fraction of steel fiber,meanwhile,the flexural toughness highly increased with volume fraction attribute to the synergetic effect of hybrid fiber.And the critical length of micro steel fiber in RPC is shorter than actual length resulting in the fracture in RPC and amounts of loading energy consumed,which can be seen from the SEM.In addition,the reinforcing mechanism of fiber on RPC was revealed,including the inter-anchor,network,bridging,interface,spalling and contortion effect.更多还原