【作者】 李磊； 郑山锁； 邓国专； 车顺利； 曾磊； 张亮； 熊宏伟； 施亮；

【Author】 LI Lei ZHENG Shan-suo DENG Guo-zhuan CHE Shun-li ZENG Lei ZHANG Liang XIONG Hong-wei SHI Liang (School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

【机构】 西安建筑科技大学土木工程学院；

【摘要】 进行了12榀不同混凝土强度等级、剪跨比、配箍率的实腹式型钢高强高性能混凝土简支梁试验,采用密布电阻应变片和滑移传感器对各级荷载作用下沿梁长度(即跨度)方向型钢应变及型钢与混凝土界面料结滑移分布进行了测量,确定了粘结应力和相对滑移的分布规律.结果表明,在界面粘结应力尚未达到局部粘结强度之前,型钢应变和界面滑移近似呈指数变化;在试件加载端粘结应力达到局部粘结强度之后,界面出现粘结软化,且粘结软化区段随荷载的增加逐渐向试件自由端扩散,型钢与混凝土协同工作的能力降低.通过对界面粘结滑移性能与诸影响因素的研究,从机理上揭示了粘结软化的形成与演化过程,分析了局部粘结强度与其主要影响因素的关系,并由试验结果统计回归得出了型钢高强高性能混凝土局部粘结强度的计算公式.研究成果为改进型钢高强高性能混凝土梁柱构件的强度、刚度、变形、裂缝宽度计算理论和有限元分析提供了试验依据.更多还原

【Abstract】 The bond- slip behaviors between shaped steel and HSHPC (high strength and high performance concrete) encasement are investigated experimentally through twelve simply supported SRHSHPC(steel rein- forced high strength and high performance concrete) composite beams of various concrete strength,shear span ratio,stirrup ratio.Strain gauges and slip sensors are lengthways placed onto the interface between shaped steel and HSHPC to measure the distribution mode of bond stress and relative slip.Steel strain and relative slip in- crease exponentially from the free end to the loading end before bond stress reaches the local bond strength;after bond stress reaches the local bond strength,the strain differenc,e between the gauges around the vicinity of the loading end becomes smaller and smaller.This behavior can be defined as bond softening,leading to progressive reduction of shear transfer capacity between steel and concrete.By studying the influence of the main parameters on interfacial bond -slip behavior,the occurrence and evolution of bond softening is made clear mechanically and the relationship between local bond strength and its influential parameters is analyzed.Based on the test re- suits,the regressive formulas of local bond strength are established.All these may contribute to the further anal- ysis of bond-slip in SRC composite structures.更多还原