考虑长期作用下的弱界面钢混组合梁动力响应分析  

Dynamic Analyses on Long-term Behavior of Composite Steel-concrete Beams with Weak Interface

作　　者：徐晨翱 Xu Chenao(College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China)

机构地区：[1]浙江大学水工结构与水环境研究所,杭州310058

出　　处：《科技通报》2024年第2期69-75,共7页Bulletin of Science and Technology

摘　　要：钢混组合梁在长期荷载作用下的动力特性受到混凝土徐变的影响,为研究动力因素与混凝土徐变因素耦合作用下的部分相互作用组合梁的动力特性,本文选择适当的状态变量来建立状态空间公式,然后得到两端简支边界条件下自由振动的频率特征方程和对应的各阶模态。公式是基于节点处的受力平衡与应变兼容性的基本力学微分方程利用D'Alembert原理推导出的,在此基础上还额外加入了考虑混凝土的徐变影响的系数项。然后采用模态叠加法计算部分相互作用组合梁在均布简谐荷载、集中移动荷载作用下的非齐次方程解以及动力响应。无论荷载类型如何,该数值模型都可以成功地用于模拟任意跨连续梁的时变结构行为。最后通过给出分析结果与数值结果的比对研究和若干相关参数研究,验证了数值模型的有效性。The dynamic response of steel-concrete composite beams applied to long-term load is affected by the creep of concrete.In order to study the dynamic behavior of partial interaction composite beams under the coupling of dynamic and concrete creep factors,appropriate state variables are selected to establish the state space formula to de-rive the frequency characteristic equations and the corresponding mode shapes of free vibration under simply-support-ed boundary conditions at both ends.The formula is derived from basic mechanical differential equations considering the stress balance and strain compatibility at each joint by using the D'Alembert principle.Besides,an additional coeffi-cient considering the effect of concrete creep is added.And the mode superposition method is used to calculate the non-homogeneous equation solution and dynamic response of partial-interaction composite beams subjected to a uni-formly distributed harmonic load and a moving constant force.Regardless of the type of load,the numerical model can be applied successfully in simulating the time-dependent structural behavior of multi-span continuous beams.Fi-nally,the validity of the numerical model is verified by comparing the analytical results with the numerical ones and some related parameters studies.

关 键 词：钢-混凝土组合梁 徐变 状态空间法 模态叠加法 滑移刚度 

分 类 号：TU398[建筑科学—结构工程]