HRB500级钢筋混凝土梁受弯性能分析  

Flexural behaviour analysis of HRB500 reinforced concrete beams

作　　者：蒋遨宇[1] 陈驹[1] 金伟良[1] 

机构地区：[1]浙江大学结构工程研究所,浙江杭州310058

出　　处：《浙江大学学报（工学版）》2013年第9期1566-1572,1671,共8页Journal of Zhejiang University：Engineering Science

基　　金：国家科技支撑计划资助项目(2006BAJ03A02);浙江省建设厅科研推广资助项目

摘　　要：为了研究HRB500钢筋在混凝土梁中的受力性能,进行了7根HRB500钢筋混凝土梁的受弯性能试验,建立了HRB500级钢筋混凝土梁受弯的数值模型.模型以梁截面上的纵向力、截面力矩、钢筋微元力等平衡方程为基础,通过求解任意弯矩作用下任意截面上的平衡方程,确定整根梁的受力响应,得到挠度、曲率、应变等随荷载的变化情况,以及混凝土裂缝宽度的发展情况.模型考虑钢筋与混凝土之间的黏结滑移和裂缝的影响,以及裂缝之间受拉区混凝土的影响,计算结果与7根试验梁结果相比较,验证了模型的准确性.利用建立的数值模型分析了HRB500级钢筋混凝土梁内钢筋与混凝土的协同工作,研究了相邻2条裂缝之间相对滑移、黏结力、混凝土和钢筋应变等的变化情况.对多因素进行参数分析,分析表明:采用高强度的混凝土能够较好地利用HRB500钢筋的高强度;随着梁截面高度的增加,裂缝宽度值成为限制梁承载力发挥的制约条件;增加保护层厚度不利于梁承载力的发挥,但影响很小可忽略.In order to investigate the mechanical performance of HRB500 rebar in concrete beams, a test program of 7 reinforced concrete beams using HRBS00 rebar was performed and a corresponding numerical model was established. Based on the axial force and bending moment equilibrium equation on beam section, as well as the translational equilibrium equations of the bar, the numerical model was developed. By solving these equilibrium equations, the response of any beam section under any load condition could be ob- tained, and the development of deflection, curvature, strain, width of cracks and so on also could be ob- tained. The effects of initial crack, bond-slip behaviour between rebar and concrete, and the contribution of the concrete in tension between adjacent cracks were taken into consideration in the model. The numeri- cal results were verified against the results of seven tested beams. Based on the developed numerical mod- el, cooperation of rebar and concrete in the bending process, distribution of slip, bonding stress, strain of rebar and so on between adjacent cracks were investigated. In addition, a parametric study was conducted to investigate the influence of several factors on the flexural behaviour of HRBS00 reinforced concrete beams. It is shown that utilization of the high strength of HRB500 rebar increases with the increasing con- crete strength. The crack width becomes the controlling factor on the bending capacity while the height of beam cross section increases. The bending capacity of beams decreases with the increasing concrete cover depth, but the effect is negligible.

关 键 词：HRB500级钢筋 钢筋混凝土梁 数值模拟 裂缝 黏结滑移 

分 类 号：TU317[建筑科学—结构工程]