钢-聚丙烯混杂纤维混凝土单轴循环受压应力-应变关系研究  

Experimental investigation on stress-strain relation of steel-polypropylene hybrid fiber reinforced concrete subjected to uniaxial cyclic compression

作　　者：徐礼华[1] 李彪[1] 池寅[1] 黄彪 李长宁 时豫川 XU Lihua, LI Biao, CHI Yin, HUANG Biao, LI Changning, SHI Yuchuan(School of Civil Engineering, Wuhan University, Wuhan 430072, Chin)

机构地区：[1]武汉大学土木建筑工程学院

出　　处：《建筑结构学报》2018年第4期140-152,共13页Journal of Building Structures

基　　金：国家自然科学基金项目(51608397,51478367);高等学校博士学科点专项科研基金项目(20130141110044)

摘　　要：为研究钢-聚丙烯混杂纤维混凝土的力学行为,对48个混凝土试件进行了单轴循环受压试验,分析纤维种类、体积掺量和长径比等因素对受压应力-应变全曲线的影响。研究结果表明：混杂纤维混凝土试件循环受压破坏呈现明显的延性特征;混杂纤维的掺入可显著改善混凝土循环力学行为,表现为混凝土峰值应力高、延性好、滞回耗能能力强、性能退化程度低等;混杂纤维对混凝土塑性应变累积具有明显约束作用;与普通混凝土相比,混杂纤维混凝土的刚度退化较慢,受纤维特征参数的影响不明显;纤维对混凝土应力退化影响较小,可忽略不计。基于试验结果以及其他相关文献的试验数据,建立了钢-聚丙烯混杂纤维混凝土单轴循环受压应力-应变关系全曲线方程,计算结果与试验结果吻合良好。In order to investigate the mechanical behavior of steel-polypropylene hybrid fiber reinforced concrete （ HFRC）, a total of 48 concrete specimens for different fiber types, fiber volume fractions and aspect ratios were fabricated and tested under uniaxial cyclic compression. The influences of fiber parameters on the complete cyclic stress-strain relation of HFRC were analyzed. The results show that the failure of HFRC is ductile. The introduction of hybrid fibers has a synergetic effect on improving the cyclic mechanical behavior of concrete, e.g. peak stress, ductility, hysteretic dissipative energy and performance degradation. The hybrid fibers can lead to a remarkable restraint in plastic strain accumulation. The stiffness degradation of HFRC is moderate than that of plain concrete,meanwhile, the influence of fiber parameters is insignificant. In addition, negligible effects of fibers on the process of stress deterioration can be observed. Furthermore, based on the experimental results and other test data reported in open literature, a constitutive model is developed to generalize the stress-strain responses under uniaxial cyclic compression of HFRC specimens. It＇ s agreed well between calculated results and test results.

关 键 词：混杂纤维混凝土 单轴循环受压试验 应力-应变关系 破坏机理 混杂效应 

分 类 号：TU528.572[建筑科学—建筑技术科学]