地震研究

采用有限差分软件FLAC3D,对防波堤结构地基地震响应进行了分析和计算,重点给出了地基液化程度和变形情况。计算结果表明:在强度较小地震作用下,防波堤结构地基破坏的程度较小,可以正常使用; 在较强地震作用下,防波堤结构地基出现了较明显的孔压增长和位移变化。当地震加速度峰值提高到0.2 g后,防波堤地基出现明显液化现象,液化区域主要集中在右侧上层。地震引发的防波堤变形对结构整体安全影响较小,对安全性影响的主要因素是砂土液化,会造成结构不同程度的破坏。

In this paper,the seismic responses of the structure foundation breakwater are analyzed and calculated using the finite difference software FLAC3D,including the emphasis on the degree of foundation liquefaction and deformation.Calculations results show that:under the strength of the smaller earthquake conditions,the breakwater structure foundation analysis is a smaller extent of the damage,and can be used normally; In the role of a strong earthquake conditions,breakwater structure can be liquefied at part of the foundation.There have been obvious changes in pore pressure and displacement variations.When the peak acceleration exesses 0.2 g the structure foundation is liquefied,Breakwater structure is a clear foundation liquefaction phenomenon,Liquefaction areas are mainly concentrated in the upper right side of the structure.Deformation of breakwater under the seismic action has a relatively small impact on overall structure safety,and the main influence factor of the security is sandy soil liquefaction which will damage structure to varying degrees.The research results on this paper can provide reference for seismic design of similar projects.

引言
1 FLAC3D数值分析原理
2 防波堤结构抗震分析
3 防波堤地基液化及变形分析结果
4 结论

图1 防波堤结构剖面图和网格模型图<br/>Fig.1 Cross-section map of breakwater structure cross plan and grid model map

图1 防波堤结构剖面图和网格模型图
Fig.1 Cross-section map of breakwater structure cross plan and grid model map

表1 岩土力学参数<br/>Tab.1 Geomechanical parameters

表1 岩土力学参数
Tab.1 Geomechanical parameters

表2 液化分析采用的流体参数及液化参数<br/>Tab.2 Fluid and liquefaction parameters for soil liquefaction analysis

表2 液化分析采用的流体参数及液化参数
Tab.2 Fluid and liquefaction parameters for soil liquefaction analysis

图2 动力分析模型<br/>Fig.2 Dynamic analysis model

图2 动力分析模型
Fig.2 Dynamic analysis model

图3 EI-Centro地震时程曲线<br/>Fig.3 EI-Centro earthquake curve

图3 EI-Centro地震时程曲线
Fig.3 EI-Centro earthquake curve

图4 EI-Centro地震傅立叶曲线<br/>Fig.4 Fourier curve of EI-Centro

图4 EI-Centro地震傅立叶曲线
Fig.4 Fourier curve of EI-Centro

图5 A、B、C、D四个监测点的位置<br/>Fig.5 A、B、C、D four monitoring points' position

图5 A、B、C、D四个监测点的位置
Fig.5 A、B、C、D four monitoring points' position

表3 不同加速度峰值监测点的超孔压比<br/>Tab.3 Excess pore pressure ratios at monitoring points of different peak accelerations

表3 不同加速度峰值监测点的超孔压比
Tab.3 Excess pore pressure ratios at monitoring points of different peak accelerations

图6 不同加速度峰值下A、B、C、D的超孔压比曲线<br/>Tab.6 Different acceleration peak under A,B,C,D of excess pore pressure ratio curve

图6 不同加速度峰值下A、B、C、D的超孔压比曲线
Tab.6 Different acceleration peak under A,B,C,D of excess pore pressure ratio curve

图7 不同加速度峰值下液化区域<br/>Fig.7 Liquefaction areas of different acceleration peak

图7 不同加速度峰值下液化区域
Fig.7 Liquefaction areas of different acceleration peak

表4 计算点水平和竖向方向位移<br/>Tab.4 Monitoring points horizontal and vertical displacements

表4 计算点水平和竖向方向位移
Tab.4 Monitoring points horizontal and vertical displacements

图8 不同加速度峰值下A、B、C、D点的水平和竖向位移图<br/>Fig.8 Different acceleration peaks under A,B,C,D points of the horizontal and vertical deformation map

图8 不同加速度峰值下A、B、C、D点的水平和竖向位移图
Fig.8 Different acceleration peaks under A,B,C,D points of the horizontal and vertical deformation map

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备注

引言

1 FLAC3D数值分析原理

2 防波堤结构抗震分析

3 防波堤地基液化及变形分析结果

4 结论

期刊信息