应变率对钢筋混凝土梁柱中节点动态性能影响的试验研究  

Experimental study of the influence of strain rate on the dynamic performance of interior reinforced concrete beam-column joints

作　　者：范国玺[1] 宋玉普[1] 王立成[1] 王德斌[2] 

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024 [2]大连交通大学,辽宁大连116024

出　　处：《土木工程学报》2014年第11期11-18,共8页China Civil Engineering Journal

基　　金：国家自然科学基金重大研究计划重点项目(90815026)

摘　　要：受材料率敏感性的影响,钢筋混凝土构件具有率敏感效应。对三个钢筋混凝土梁柱中节点组合体抗震性能试验,采用位移控制方式加载,研究节点组合体裂缝发展、承载能力、变形能力等随加载速率的影响规律。研究结果表明:不同应变率作用下,节点组合体均发生弯剪破坏,但应变率提高后,节点组合体内的裂缝数量减少,裂缝分布更集中;节点组合体承载能力随应变率的提高而增大,受钢筋动态强度的影响,节点组合体屈服荷载较极限荷载增长更明显;相对低应变率作用,高应变率作用下节点组合体在破坏前的耗能增加;应变率提高后,节点组合体的刚度增大,但由于惯性力的影响,超过一定范围后,其刚度退化加剧,应变率提高对试件的刚度有不利影响;应变率提高后,黏结滑移更明显,但节点组合体的变形能力没有减弱。Due to the material rate sensitivity, the reinforced concrete members are generally sensitive to the strain rate. In this work, the seismic behavior of 3 interior reinforced concrete beam-column joints were studied under the displacement-controlled loading , aiming at attaining a better understanding .of the effect of loading speed on the crack development, carrying capacity, deformation capacity of the joint assembly and so on. The results show that joint assemblies with various strain rates have the identical shear failure modes which may occur in the joint core area after the plastic hinges develop at both ends of adjacent beams. With the increase of strain rate, however, the number of cracks within the joint assembly may decline and the cracking distribution becomes more concentrated. With the increase of strain rate, the carrying capacity of the joint assembly may be improved. Due to the dynamic strengths of steel, the improvement of the yield carrying capacity is more significant than that of the ultimate carrying capacity. Moreover, before the final failure is reached, the energy dissipation of the joint assembly under a higher strain rate is larger than that under a lower strain rate. Due to the increase in strain rate, the stiffness of the joint assembly can be enhanced. But beyond a certain range, the stiffness may decline sharply due to the effect of inertia force, and the increase of strain rate may have adverse effect. With the increase of strain rate, the bond slip becomes more significant, while the deformation capacity of the joint assembly remains almost unchanged .

关 键 词：钢筋混凝土梁柱中节点 应变率 延性 耗能 

分 类 号：TU375.4[建筑科学—结构工程]