土-结构动力相互作用下网架结构简化分析方法研究  

Simplified analysis method of grid structure considering soil-structure dynamic interaction

作　　者：刘毅[1] 薛素铎[1] 李雄彦[1] 王国鑫[1] 

机构地区：[1]北京工业大学空间结构研究中心,北京100124

出　　处：《振动与冲击》2015年第11期75-82,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金资助项目(51078010;51278008);北京市自然科学基金资助项目(8112005)

摘　　要：根据不同学者有关地基动力阻抗的计算公式,结合整体有限元法,从工程应用出发对S-R(Swing-Rocking)模型进行修正,提出适用于分析土-结构动力相互作用下大跨空间结构的简化计算方法。基于修正的S-R模型建立土-网架结构动力相互作用的计算模型,与已验证的三维整体有限元(3-D)模型进行对比分析。研究表明,根据修正S-R模型计算所得土-网架结构相互作用体系的自振特性和地震响应与已验证的3-D模型结果呈现出完全一致的规律性且吻合较好,从而验证了修正S-R模型的合理性;在不同地震波作用下,采用Gazetas提出的地基动力阻抗公式建立的土-网架结构相互作用体系中网架节点最大位移和峰值加速度与已验证的3-D模型结果最大误差不超过8.0%,结构杆件内力最大误差不超过10%,表明Gazetas提出的地基动力阻抗公式更适用于分析土-大跨空间结构动力相互作用问题,且具有较好的精度。Based on the foundation dynamic impedance calculation formulas suggested by different scholars,the S-R （swing-rocking）model was modified by combining with the integral finite element method and starting from the view point of engineering application.The practical simplified calculation method suitable for the soil-structure dynamic interaction analysis of long-span spatial structures was proposed.Then,the model of soil-grid structure interaction was established according to the modified S-R model,and the three-dimensional finite element model verified was also established for a comparative analysis.The study showed that the natural vibration properties and seismic response of the soil-grid structure interaction model based on the modified S-R model reveal same regularities and agree well with those of the 3-D FE model,the rationality of the modified S-R model is verified;the nodal maximum displacement error and peak acceleration error of the soil-grid structure interaction system established with the foundation dynamic impedance calculation formulas proposed by Gazetas are less than 8.0%,and the maximum stress error of members is less than 10%compared with those obtained with the 3-D FE model under different seismic waves;thus the foundation dynamic impedance calculation formulas proposed by Gazetas are more suitable for the analysis of soil-large span spatial structure interaction and have a higher precision.

关 键 词：网架结构 土-结构动力相互作用 修正S-R模型 自振特性 地震响应 

分 类 号：TU311.3[建筑科学—结构工程]