【摘要】 在传统双弹簧联结单元法的基础上,提出了一种求解钢筋与混凝土黏结滑移问题的新方法——基于混合坐标系的单弹簧联结单元法.在混凝土实体单元与钢筋梁(杆)单元的切向设置单弹簧联结单元,模拟钢筋与混凝土切向的相互作用,其切向刚度同样是由钢筋与混凝土之间黏结力与滑移量的关系确定.混凝土实体单元在整体坐标系内求解,而为了方便建立法向自由度之间的关系,钢筋梁单元在局部坐标系内求解,通过建立法向自由度约束方程保证钢筋与混凝土的法向变形协调,避开了人为选择法向刚度系数的困难,能够很方便地考虑钢筋对混凝土的销拴效应,并且也适用于钢筋单元在混凝土中任意布置的情况.数值算例表明,该方法是正确和有效的.更多还原

【Abstract】 Based on the traditional double-spring joint element method,a new method—single-spring joint element method based on the mixed coordinate system, was proposed for bond-slip problems of steel bars and concrete.The single-spring joint elements were arranged along the tangential direction of the solid elements for concrete and the beam elements for steel bars to simulate the tangential interaction.The tangential stiffness was determined by the relationship between the bond force and slip.The solid elements for concrete were solved in the global coordinate system.In order to establish the relationship among the normal direction degrees of freedom,the beam elements for the steel bars were solved in the local coordinate system.The deformation compatibility between concrete and steel bars was ensured by means of the establishment of restraint equations of the normal degrees of freedom,overcoming the difficulty to choose the normal stiffness coefficients,and it was available to arbitrary layout of beam elements for steel bars in concrete.The validity and accuracy of the proposed procedure was demonstrated by numerical examples.更多还原