自密实混凝土梁抗剪性能试验研究  

Experimental study on the shear performance of self-compacting concrete beam

作　　者：陈成方 王岱 CHEN Chengfang;WANG Dai(School of Civil Engineering,Tianjin Chengjian University,Tianjin 300380,China;Tianjin Key Laboratory of Civil Buildings Protection and Reinforcement,Tianjin 300380,China)

机构地区：[1]天津城建大学土木工程学院,天津300380 [2]天津市土木建筑结构防护与加固重点实验室,天津300380

出　　处：《四川建筑科学研究》2020年第2期50-56,共7页Sichuan Building Science

基　　金：天津市自然科学基金(17JCYBJC21700);天津市科技计划项目(19PTZWHZ00080)。

摘　　要：针对自密实钢筋混凝土梁的塑性开裂问题,提出了在自密实混凝土无腹筋梁中加入钢纤维,以约束混凝土内部裂隙扩展,从而提高其抗剪承载力。通过试验进行了钢纤维掺入量对自密实混凝土无腹筋梁抗剪承载力的影响规律研究。结果表明:当钢纤维体积率低于0.5%时,钢纤维对梁抗剪承载力的影响很小;当钢纤维体积率在0.5%~2%时,梁的开裂裂隙数量减少、裂隙长度缩短、分布范围减小,钢纤维明显提高了梁的抗剪承载力和延展塑变性能;值得指出的是,当钢纤维体积率超过1.5%后,梁抗剪能力的增长趋于平缓。Against the plastic cracking of reinforced self-compacting concrete beams,this paper proposed to add steel fiber into the beams without web reinforcement to restrict the expansion of internal cracks in the concrete,so as to improve its shear capacity.The influence of steel fiber share in self-compacting concrete beams without web reinforcement on its shear performance was studied through experiments.Results show that when steel fiber volume fraction is less than 0.5%,it has little impact on the beam shear performance.While the steel fiber volume fraction is between 0.5%and 2%,there will be decrease in beam crack fracture,beam crack length and beam crack distribution range,which demonstrates that the increase of steel fiber share contributes to raising shear capacity and the extension and deformation performance of beams.It is worth pointing out that the growth trend of the shear performance will level off after the steel fiber volume fraction exceeds 1.5%.

关 键 词：钢纤维 自密实混凝土 无腹筋梁 抗剪性能 承载力 

分 类 号：TU375.1[建筑科学—结构工程]