爆炸荷载下弹性支撑地下拱结构的动力响应  

Research on Dynamic Response of the Underground Arch Structure with Elastic Support under Condition of Explosive Load

作　　者：陈卓[1] 孙惠香[1] 袁英杰 冷冰林 王英武 CHEN Zhuo;SUN Huixiang;YUAN Yingjie;LENG Binglin;WANG Yingwu(Aeronautics Engineering College,Air Force Engineering University,Xi’an 710038,China;Engineering Quality Supervision Station,Unit 95338,Guangzhou 510030,China;Xi’an Institute of Optics and Precision Machinery,Chinese Academy of Sciences,Xi’an 710068,China)

机构地区：[1]空军工程大学航空工程学院,西安710038 [2]95338部队工程质量监督站,广州510030 [3]中国科学院西安光学精密机械研究所,西安710068

出　　处：《空军工程大学学报（自然科学版）》2020年第6期93-100,共8页Journal of Air Force Engineering University(Natural Science Edition)

基　　金：国家自然科学基金(51208506)。

摘　　要：弹性支撑是常用的隔振减振手段,研究爆炸荷载下弹性支撑地下拱结构的动力响应对提高地下防护工程内部人员及设备的战场生存能力具有重要意义。应用ANSYS/LS-DYNA非线性显式动力有限元分析程序,模拟了爆炸荷载下弹性支撑地下拱结构的模态和动力响应,得到了低阶自振圆频率变化曲线和拱顶、拱肩、拱脚动力响应时程曲线。结果表明:弹性支撑减小结构固有频率,延长结构自振周期,具有良好隔振减振作用;临界刚度系数导致结构的一、二阶模态易同时激发,结构设计时应予以避免;与刚性支撑地下拱结构相比,弹性支撑地下拱压力、应力峰值减小,出现时间延长,竖向位移峰值增大,抗爆承载力提高;弹性支撑的刚度系数并非越小越好,应根据结构抗爆承载力和极限位移设计要求合理设置。Elastic support is a commonly used means to the vibration isolation and the vibration reduction.Research on the dynamic response of elastically supported underground arch structures under under condition of explosive loads is of great significance for improving the battlefield survivability of personnel and equipment in underground protection projects.In this Paper,the ANSYS/LS-DYNA nonlinear explicit dynamic finite element analysis program is applied to simulate the modal and dynamic response of underground arch structure with elastic support under condition of blast load,thus obtaining the low order natural frequency variation curve and the dynamic response time history curve of arch crown,arch shoulder and arch foot.The results show that the elastic support reduces the natural frequency of the structure,extends the natural vibration period of the structure,and has a good vibration isolation and vibration reduction effect.With the critical stiffness coefficient leading the first and the second modes of the structure to be easily excited at the same time,such a case should be avoided in the structural design.Compared with rigidly supported underground arches,the elastically supported underground arche is low in pressure and stress peaks,long in their appearance,good in vertical displacement peaks,and improvement in blast resistance.As for the stiffness coefficient of the elastic support,this does not mean the less the better without principle,it should be done reasonably according to the structural anti-blasting capacity and ultimate displacement design requirements.

关 键 词：爆炸荷载 弹性支撑 地下拱结构 动力响应 数值模拟 

分 类 号：TU928[建筑科学—建筑设计及理论]