滑动支座横向限位装置对地面明钢管地震响应的影响  

Influence of Transverse Displacement Restrainer of Sliding Supporton the Seismic Response of Exposed Steel Penstock

作　　者：耿丽娇 徐红超 蔡微微 童保林 张荣斌 王梅芳 石长征[3] GENG Li-jiao;XU Hong-chao;CAI Wei-wei;TONG Bao-lin;ZHANG Rong-bin;WANG Mei-fang;SHI Chang-zheng(Yunnan Institute of Water Resources and Hydropower Survey,Design and Research,Kunming 650021,China;Central Yunnan Water Diversion Engineering Co.,Ltd.,Kunming 650000,China;State Key Laboratory of Water Resources Engineering and Management,Wuhan University,Wuhan 430072,China)

机构地区：[1]云南省水利水电勘测设计研究院,昆明650021 [2]云南省滇中引水工程有限公司,昆明650000 [3]武汉大学水资源工程与调度全国重点实验室,武汉430072

出　　处：《长江科学院院报》2024年第10期195-200,共6页Journal of Changjiang River Scientific Research Institute

基　　金：云南省重大科技专项计划项目(202102AF080001)。

摘　　要：针对地震作用下地面明钢管滑动支座容易产生较大横向滑移的问题,采用有限元方法,研究了支座限位装置对明钢管地震响应的影响。计算结果显示:当支座不设置限位装置时,地震作用下管段中部支座滑移量较大,钢管横向弯曲,对结构稳定不利;当支座设置限位装置后,明钢管的横向位移减小,但在地震中支座滑板与限位装置会产生碰撞,瞬时加速度可超100 m/s 2,支承环的应力大幅增加,支座横向力可达静力状态下的几十甚至上百倍;支座限位值越小,地震中结构受力越大;支座限位挡块和支座滑板接触面上设置一层弹性模量3 MPa的薄垫层后,能缓冲地震中支座受到的冲击,有效减小结构加速度和受力,支座横向力和竖向力的比值可基本控制在摩擦系数以内。因此,支座限位对强震区的明钢管结构是有必要的,在确定限位值时,应同时考虑结构位移和应力2个方面的要求,为减小地震中支座滑板和限位装置碰撞产生的不利影响,可在限位挡块上设置缓冲材料薄层。In response to significant lateral sliding of exposed steel penstocks during earthquakes,this study investigates the impact of displacement restrainers on the seismic response of exposed steel penstocks using finite element method.The results reveal that without restrainer,the sliding distance of the support at the midpoint of the pipe segment increased considerably during earthquake,leading to significant lateral bending of the steel pipe,detrimental to structural stability.Conversely,installing a restrainer controlled the lateral displacement of the exposed steel pipe within acceptable limits.However,during earthquakes,the sudden restriction of the sliding support led to substantial collisions between the sliding plate and the restrainer,causing instantaneous accelerations exceeding 100 m/s 2.The lateral forces on the support surged to 10 or even 100 times the static forces,significantly increasing the stress on the support ring.Lower limit value resulted in higher structural stress during earthquakes.By adding a thin cushion layer with an elastic modulus of 3 MPa between the restrainer and the support sliding plate,the forces on the support were mitigated,effectively reducing structural acceleration and stress.This adjustment kept the ratio of lateral to vertical forces on the support below the friction coefficient.Therefore,a support restrainer is essential for exposed steel penstocks in seismic zones.Meanwhile,it is crucial to consider both displacement and stress requirements when determining the restrainer’s limit value.To minimize adverse impacts of the collision between the support sliding plate and the restrainer during earthquakes,installing a thin buffer layer on the restrainer is recommended.

关 键 词：明钢管 地震响应 滑动支座 限位装置 

分 类 号：TV731[水利工程—水利水电工程]