双层连续组合梁弹塑性状态的界面滑移

Interface slip of double continuous composite beam in inelastic state

考虑了上层混凝土开裂及钢筋与混凝土之间滑移对梁变形的影响.根据剪力连接件的实际力学特性,采用简化后的线弹性弹簧来模拟钢筋-混凝土界面以及钢梁-混凝土界面的剪切滑移,并结合内力-变形关系推导出双层钢-混凝土组合梁的上下层界面滑移微分方程.在分析过程中偏保守地假设负弯矩截面上缘混凝土板抗拉刚度降为零.为验证该解析法的合理性,采用非线性较强的有限元软件Abaqus建立了空间模型,模型考虑了剪力连接件和材料的非线性.有限元计算结果表明,通过2种方法所得的界面滑移数值和趋势比较吻合,该解析法用于分析双层连续组合梁的滑移变形是可行的.

This work considered the influences of upper concrete slab cracks and interface slip between rebar or steel girder and concrete on beam deformation. A simplified linear spring element was used to model the interface action and a differential equation was presented based on the internal force-deformation mechanical behaviour of shear connector. In the process of analysis, the upper concrete slab was supposed could not endure tension stress when cracks develop for security consideration. A three-dimensional finite element model was set up to validate the reliability of the theoretical method using the software of Abaqus. The nonlinear mechanics behaviour of shear connector and material was considered in the finite element model. The finite element model result showed that the numerical value and the trend of interface slip gained from these two methods were nearly consistent, which shows that the proposed theoretical method is feasible to analyze the double continuous composite beam.