摘要
西南山区大部分为具覆盖层下伏基岩场地,并且地势陡峻。在其输电线路工程中,场地在地震作用下的稳定性对上部杆塔结构的安全影响较为明显。目前对于不同场地条件对地震动的影响有一定的研究,但针对西南山区陡坡地形,特别是具基岩场地中基岩强度对场地地震效应的研究还较少。以西南山区某典型输电线路场地为研究对象,采用FLAC3D数值分析软件,运用时程分析方法,分析场地地震峰值加速度放大系数、场地永久位移随覆盖层厚度和基岩强度的变化特征,探讨西南山区不同场地地基条件的地震效应。研究表明:随着覆盖层厚度的增加,场地峰值加速度放大系数逐渐减小、永久位移逐渐增大;随着基岩强度的增大,场地水平峰值加速度放大系数逐渐减小,竖向峰值加速度放大系数逐渐增大、永久位移逐渐减小。
Most of southwest mountainous areas are underlying bedrock ground cover layer, and the terrain is steep. In the transmission line engineering, the influence of the site stability under seismic action on the safety of upper tower structure is obvious. At present, there are some researches on the influence of different site conditions on seismic effect, but there are few researches for the southwest steep terrain, especially for the influence of the bedrock strength in the rock sites on the seismic effect of the site. Taking a typical transmission line site in southwestern mountainous area as research object, with using numerical analysis software FLAC3D and time history analysis method, this paper analyzed the seismic peak acceleration amplification coefficient on site, the variation characteristics of the permanent displacement on site along with the cover thickness and bedrock strength, and discussed the seismic effect of different site conditions in southwest mountainous area. The results show that： with the increase of cover thickness, the peak acceleration amplification coefficient gradually decreases, and the permanent displacement gradually increases ; with the increase of bedrock strength, the vertical peak acceleration amplification coefficient gradually increases, and the horizontal peak acceleration amplification coefficient and the permanent displacement gradually decrease.
出处
《电力建设》
北大核心
2015年第6期40-45,共6页
Electric Power Construction
基金
国家重点基础研究发展计划项目(973计划)(2011CB013501)
长江学者和创新团队发展计划(IRT0812)~~
关键词
场地条件
西南山区
输电线路
地震效应
site condition
southwest mountain area
transmission line
seismic effect
