摘要
未来地震的发生具有一定的随机性,以研究区遭受一定超越概率水平地震动作用所开展的滑坡危险性区划,忽视了部分潜在发生的地震的影响,是一种条件概率下的危险性区划。基于概率地震危险性分析及Newmark累积位移评估模型,以滑坡概率为危险性指标,提出一种考虑潜在地震影响的概率性地震滑坡危险性区划新方法,并可对震源机制、场地类型及地形高度的影响进行修正。以天水研究区为例,采用第五代地震动参数区划图的潜在震源区划分方案,结合研究区工程地质岩性分组及地形高程数据,对研究区未来50 a内地震滑坡危险性进行区划,结果表明地震滑坡中、高危险区主要集中于黄土覆盖或泥岩出露且斜坡坡度大于30°的地区,其中又以渭河及其支流藉河、牛头河两岸部分地区的地震滑坡危险性较高,对天水市区周边及陇海铁路线构成威胁。
Earthquake is a random process. Recent landslide hazard analyses were carried out based on ground motions with given probability of exceedance, ignoring the impact of some potential earthquakes, representing a conditional probability of earthquake induced landslides. This paper presents a new method for potential seismic landslide hazard zonation at regional scale in terms of landslide probability. It is based on the probabilistic seismic hazard analysis and Newmark＇s displacement model, incorporating the effects of focal mechanism, site condition and topography. We applied this method to Tianshui study area and generated a regional seismic landslide probability hazard map in 50 years, combining the potential seismic source zones which were used for the new generation seismic zonation map of China, empirical engineering geology lithology formations, and topographic slop data. The results show that the high hazard zones mainly concentrated at the loess or mudstone areas with slope greater than 30 degree, especially on the banks of Wei River, Xi River and Niutou Revier, posing a threat to Longhai Railway line and the surrounding of Tianshui city.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2016年第A01期3100-3110,共11页
Chinese Journal of Rock Mechanics and Engineering
基金
国家公益性地震行业专项(201408014)
中国地质调查局地质调查项目(12120114035501)
国家自然科学基金资助项目(41372374)~~
