沉箱式靠船防波堤结构地震响应数值分析  

Numerical analysis of seismic response for caisson type berthing breakwater structure

作　　者：倪晓雯 刘子宜 NI Xiaowen;LIU Ziyi(Shandong Jianyan Testing and Inspection Technology Co.,Ltd.,Jinan 250031,China;Shenzhen Merchants Qianhai Bay Real Estate Co.,Ltd.,Shenzhen,518101,China)

机构地区：[1]山东建研检测检验科技有限公司,山东济南250031 [2]深圳市招商前海湾置业有限公司,广东深圳518101

出　　处：《水运工程》2024年第8期175-180,共6页Port & Waterway Engineering

摘　　要：针对沉箱式靠船防波堤结构在地震作用下的安全性评估问题,基于有限单元法,采用考虑砂土液化模式的广义弹塑性本构算法建立沉箱式靠船防波堤二维断面计算力学模型,开展地震波作用下结构时间历程动力响应数值模拟研究,并根据计算结果对结构的安全性进行评价。研究结果表明:在峰值0.1g的多遇地震作用下,沉箱式靠船防波堤结构的最大水平和竖直加速度放大倍数约为1.6,符合地震波在分层土体中传播的一般规律;在多遇地震作用下,防波堤的整体抗滑安全系数和主要沉箱构件的最不利抗倾和抗滑稳定性系数均大于设计标准;在峰值0.2g的罕遇地震作用下,广义弹塑性本构模型可以准确模拟地震过程中,地基粉细砂层的孔隙水压力上升和抗液化安全系数降低的过程。在此基础上,计算模型可以准确评估沉箱式靠船防波堤在地震作用下的累积变形量,从而充分论证防波堤结构在罕遇地震下的可靠性。To the safety evaluation of the caisson type berthing breakwater structure under earthquake action,this paper establishes a two-dimensional computational model of the caisson type berthing breakwater based on the finite element method and the generalized elastoplastic constitutive algorithm,which considering sand liquefaction mode.Numerical simulation research on the time history dynamic response of the structure under earthquake wave action is carried out,and the safety of the structure is evaluated based on the calculation results.The research results indicate that under the frequent encountered earthquake action with a peak acceleration value of 0.1 g,the maximum horizontal and vertical acceleration amplification factor of the caisson type berthing breakwater structure is about 1.6,which conforms to the general law of seismic wave propagation in layered soil.Under frequent encountered seismic action,the overall anti-sliding safety factor of the breakwater and the most unfavorable anti-tilting and anti-sliding stability factors of the main components caisson are both greater than the design standards.Under rare encountered earthquakes with a peak acceleration value of 0.2 g,the generalized elastoplastic constitutive model can accurately simulate the process of pore water pressure increase and liquefaction resistance safety factor decrease in the fine sand layer of the foundation during earthquakes.On this basis,the calculation model can accurately evaluate the cumulative deformation of the caisson type berthing breakwater under earthquake action,thereby fully demonstrating the reliability of the breakwater structure under rare encountered earthquakes.

关 键 词：沉箱式靠船防波堤 广义弹塑性模型 加速度分布 砂土液化 变形响应 

分 类 号：TV148[水利工程—水力学及河流动力学] U65[交通运输工程—港口、海岸及近海工程]