箍筋约束混凝土圆柱轴压破坏尺寸效应行为  

SIZE EFFECT ON THE FAILURE OF STIRRP-CONFINED REINFORCED CONCRETE COLUMNS UNDER AXIAL COMPRESSION

作　　者：金浏[1] 杜敏[1,2] 杜修力[1] 李振宝[1] JIN Liu;DU Min;DU Xiu-li;LI Zhen-bao(The key laboratory of Urban Security and Disaster Engineering, Beijing University of Technology, Beijing 100124, China;Department of Disaster Prevention Engineering, Institute of Disaster-prevention Science and Technology, Sanhe, Hebei 065201, China)

机构地区：[1]北京工业大学城市减灾与防灾防护教育部重点实验室,北京100124 [2]防灾科技学院防灾工程系,河北三河065201

出　　处：《工程力学》2018年第5期93-101,共9页Engineering Mechanics

基　　金：国家自然科学基金创新研究群体项目(51421005);国家自然科学基金项目(51408127);教育部创新团队项目(IRT13044)

摘　　要：开展了12组不同尺寸几何相似的箍筋约束混凝土圆柱轴心受压破坏试验,试验的工况参数为:配箍率为1.26%和2.89%;圆柱尺寸(直径)相似比为1∶1.5∶2.25,圆柱最大直径为576 mm;圆柱长细比为3。根据试验结果探讨了箍筋约束作用混凝土圆柱破坏模式及轴压强度尺寸效应的影响规律。基于Ba?ant尺寸效应律思想,提出了能反映尺寸影响的箍筋约束混凝土圆柱轴压承载力计算理论,与试验结果的良好吻合证明了修正承载力计算理论的合理性。最后,建立了钢筋混凝土柱破坏行为及尺寸效应模拟的3D细观尺度数值分析方法,在模拟结果与试验结果吻合良好的基础上,扩展模拟了更大尺寸圆柱的破坏行为。A total of 12 geometric similar stirrup-confined circular reinforced concrete（RC） columns subjected to axial compression were designed and tested. In the tests, two stirrup ratios of 1.26% and 2.89% were utilized. The structural similarity ratio of the columns was 1∶1.5∶2.25. The maximum cross-sectional diameter was 576 mm, and the slenderness ratio was 3. The confinement effect on the failure patterns and the axial compressive strength of the stirrup-confined columns was explored. Moreover, based on the basic theory of the Size Effect Law（SEL） proposed by Ba？ant, a modified formula for evaluating the bearing capacity of stirrup-confined RC columns was developed, which can reflect the effect of structural size. Good agreement between the theoretical results and the test results indicated the reasonability of the modified formula. Finally, a 3 D meso-scale numerical method for the simulation of the failure behavior and size effect of RC members was established. The simulated results were consistent with the tested ones, and the meso-scale simulation method was then extended to model the failure of circular RC columns with larger structural dimensions.

关 键 词：箍筋约束混凝土 圆柱 轴压强度 箍筋率 尺寸效应 承载力 细观数值模拟 

分 类 号：TU528[建筑科学—建筑技术科学]