钢-混凝土组合梁界面滑移剪切变形的双重效应分析

ANALYSIS OF COMPOSITE BEAMS OF STEELAND CONCRETE WITH SLIPAND SHEAR DEFORMATION

组合梁界面滑移将减小组合梁刚度,增大变形,影响构件性能。同时组合梁往往重载,具有较小的跨高比,剪切变形不可忽略。根据最小势能原理和变分法,建立了同时考虑滑移效应和剪切变形双重作用的挠度滑移控制微分方程,分析了滑移引起挠度增大的原因,求得了集中荷载和均布荷载作用下的挠度和滑移的解析表达式。该方法物理意义明确,推导过程简单,计算结果与实测结果吻合良好。推导了不同荷载作用下的滑移效应附加弯矩,利用附加弯矩表达公式,可直接利用结构力学挠度计算公式计算滑移对挠度的影响。

The interfacial slip reduces the stiffness, increases deformation and influences performance of composite beams of steel and concrete. Since the loads on composite beams are large and the span-depth ratio is low, the shear deformation cannot be neglected. This paper presents the differential governing equations of composite beams based on minimum potential energy and variational method. Both shear deformation and interfacial slip are taken into account. The expressions for deflection and interfacial slip are obtained for beams subjected to concentrated and distributed loads. The results of the present method are in good agreement with other numerical solutions and experimental results. The expressions of additional bending moment due to interfacial ship for concentrated and distributed loads are presented, with which the additional deflection due to interfacial slip deformation can be estimated.