基于Newmark滑块位移法的岸坡地震稳定性简易分析方法  

Simplified analysis method of bank slope seismic stability based on Newmark’s sliding block method

作　　者：高树飞 冯云芬[1] GAO Shu-fei;FENG Yun-fen(School of Architecture and Civil Engineering,Liaocheng University,Liaocheng 252000,China)

机构地区：[1]聊城大学建筑工程学院,山东聊城252000

出　　处：《水运工程》2022年第6期40-48,共9页Port & Waterway Engineering

基　　金：山东省自然科学基金资助项目(ZR2018BEE046);聊城大学科研基金资助项目(318012111,318011916)。

摘　　要：国外码头抗震设计规范普遍采用地震永久变形分析岸坡稳定性,而地震永久变形一般是由基于Newmark滑块位移法确立的经验公式或图表计算得到的,但我国水运工程抗震设计规范并无类似方法。为此采用Newmark滑块位移法对3 600条拟合于我国水运工程抗震设计规范反应谱的人工地震波进行分析,确定了滑块位移的统计特征和分布。由此提出了一种简易分析方法,并通过一个实际码头岸坡案例说明了方法的实施过程。研究结果表明:1)基于Newmark滑块位移法确定的永久变形均值是岸坡屈服加速度的函数,其变异系数是屈服加速度和峰值地面加速度比值的函数,且永久变形服从对数正态分布;2)可将表达式计算得到的永久变形均值同规定的限值进行直接对比来分析岸坡稳定性,也可通过计算一定保证率下的变形来分析。Overseas seismic design codes of wharfs commonly utilize earthquake-induced permanent deformation for the stability analysis of bank slope,and the deformation is determined by empirical formula or charts,which are established based on the Newmark’s sliding block method.However,there is no similar method in the seismic design codes for water transport engineering in China.Thus,the Newmark’s sliding block method is conducted to analyze 3,600 artificial seismic waves which fitting the response spectrum of the seismic design code for water transport engineering in China,and the statistical characteristics and distribution of block displacements are determined.Therefore,a simple analysis method is proposed,and the implementation process of the method is illustrated by a case of a real wharf bank slope.The results show that:1)The mean value of permanent deformation determined based on the Newmark’s sliding block method is a function of yield acceleration of the bank slope.The coefficient of variation is a function of the ratio of yield acceleration to the peak ground acceleration.The permanent deformation obeys a logarithmic normal distribution.2)The stability of the bank slope can be analyzed by directly comparing the mean permanent deformation calculated by proposed equation with the specified limited value,or by calculating the deformation value under a certain guarantee rate to conduct the corresponding stability analysis.

关 键 词：岸坡 地震永久变形 稳定性 Newmark滑块位移法 保证率 

分 类 号：U656[交通运输工程—港口、海岸及近海工程]