动力作用下边坡时频响应分析  

Time-Frequency Response Analysis of Slope Under Dynamic Action

作　　者：杨廷玺 YANG Ting-xi(China Railway 18th Bureau Group Co.,Ltd.,Tianjin 300222,China)

机构地区：[1]中铁十八局集团有限公司,天津300222

出　　处：《广东水利电力职业技术学院学报》2025年第1期33-38,52,共7页Journal of Guangdong Polytechnic of Water Resources and Electric Engineering

基　　金：高陡路堑边坡长期稳定性及监测评估技术研究(0-JF-2019-兴泉-01)。

摘　　要：为研究岩质边坡在动力作用下的破坏机理,以我国南方某边坡为原型进行动力响应分析试验。通过大比例尺非均质岩质边坡的振动台试验,获取边坡模型在不同波形下的不同位置位移响应、土压力响应和加速度响应数据,采用希尔伯特黄变换进行时频分析。试验结果表明:岩质边坡分为弹性变形阶段、塑性变形阶段、破坏阶段3个阶段。边坡模型具有鞭梢效应,对频率为5 Hz的动力响应要明显高于10 Hz和EL Centro波,在动力作用下有随加速度放大效应。随着加速度峰值增大,动土压力逐渐增大,固有频率逐渐减小。岩土体EL波响应信号前五阶模态与其相关性更好,为响应信号主要组成部分。响应信号频率主要集中在1~50 Hz,高频部分主要分布在时程2~10秒之间。坡肩与坡腰响应波的高能量频带分布范围差异是坡肩剪切带形成的诱因。碎裂岩土较完整岩土的响应波频率分布范围更高,故可根据频率分布范围进行坡体的损伤识别及破碎程度分类。In order to study the failure mechanism of rock slope under dynamic action,a slope in southern China is taken as a prototype to conduct dynamic response analysis test.A large-scale vibration table test of a heterogeneous rock slope model was performed to obtain displacement,soil pressure,and acceleration response data at different locations under various waveforms.The Hilbert-Huang Transform(HHT)was applied for time-frequency analysis.The test results show that the rock slope is divided into three instability stages:elastic deformation,plastic deformation and failure.The slope model has a whipping effect,with dynamic responses at a frequency of 5 Hz being significantly higher than those at 10 Hz and the El Centro wave.There is an amplification effect in acceleration under dynamic action.As the peak acceleration increases,dynamic soil pressure gradually increases,and the natural frequency gradually decreases.The first five modal responses of the El Centro wave for the rock-soil show a better correlation,serving as the primary components of the response signal.The frequency of the response signal is mainly concentrated between 1-50 Hz,with the high-frequency part predominantly distributed between 2-10 seconds.The difference in the distribution range of the high energy frequency band of the response wave between the slope shoulder and the slope waist is a key factor in the formation of shear zones at the slope shoulder.The frequency distribution range of response wave of fractured rock is higher than intact rock.According to the frequency distribution range,slope damage and the degree of fragmentation can be identified.

关 键 词：边坡 振动台 PGA 固有频率 时频分析 希尔伯特黄变换 

分 类 号：P642[天文地球—工程地质学]