李京军1,2，牛建刚1，刘洪振1，朱聪1，张缜3

（1 内蒙古科技大学， 包头 014010； 2 重庆大学， 重庆 400045； 3 蚌埠学院， 蚌埠 233030）

［摘要］通过四点受弯试验，研究了钢纤维掺量对轻骨料混凝土荷载-挠度曲线的影响。借助于ASTM-C 1018法、ASTM-C 1399法、JSCE-SF4法、剩余强度法和PCSm法这五种方法，得出不同方法下的钢纤维轻骨料混凝土弯曲韧性指标。通过与不同钢纤维掺量下钢纤维轻骨料混凝土荷载-挠度曲线的变化规律相对比，提出更加适用于衡量钢纤维轻骨料混凝土韧性的评价方法。结果表明，剩余强度法所求得的钢纤维轻骨料混凝土韧性指标随钢纤维掺量变化规律与荷载\-挠度曲线随钢纤维掺量变化规律相一致，可以用来衡量钢纤维轻骨料混凝土的韧性。

［关键词］钢纤维； 轻骨料混凝土； 弯曲韧性指标； 最佳方法

中图分类号：TU528.2文献标识码：A文章编号：1002-848X(2016)02-0039-04

Comparative study of evaluation methods for toughness index in steel fiber reinforced

lightweight aggregate concrete

Li Jingjun1,2, Niu Jiangang1, Liu Hongzhen1 , Zhu Cong1 , Zhang Zhen3

（1 Inner Mongolia University of Science and Technology， Baotou 014010， China；

2 Chongqing University, Chongqing 400045, China； 3 Bengbu College， Bengbu 233030， China）

Abstract:By four-point bending test, the influence of steel fiber content on the load-deflection curve of steel fiber reinforced lightweight aggregate concrete was investigated. Five methods of ASTM-C 1018, ASTM-C 1399, JSCE-SF4, residual strength method and PCSm were employed to obtain flexural toughness index of steel fiber reinforced lightweight aggregate concrete respectively. The changing laws of load-deflection curves of steel fiber reinforced lightweight aggregate concrete with different steel fiber mixtures were compared, and the optimal evaluation method for measuring the flexural toughness of steel fiber reinforced lightweight aggregate concrete was proposed. The results show that for residual strength method, obtained changing law of flexural toughness index along with steel fiber mixture is in accordance with the changing law of load-deflection curve along with steel fiber mixture. And the residual strength method can be used to measure the toughness of steel fiber reinforced lightweight aggregate concrete.

Keywords:steel fiber; lightweight aggregate concrete; flexural toughness index; optimal method

*国家自然科学基金资助项目（51368042），内蒙古自然科学基金（2014MS0528）。

作者简介：李京军，博士研究生，Email:642229851@qq.com。