板桥学校液化带工程地质条件及液化土层特性  

Characteristics of engineering geology and liquified soil layer of the Bianqiao School liquefaction zone

作　　者：侯龙清[1,2] 陈松 陈革 徐红梅[1,2] 程丽红[1,2] 

机构地区：[1]东华理工大学建筑工程学院 [2]东华理工大学放射性地质与勘探技术国防重点学科实验室,南昌330013 [3]核工业德阳金阳岩土工程有限公司,德阳618000

出　　处：《水文地质工程地质》2012年第1期102-106,共5页Hydrogeology & Engineering Geology

基　　金：国家科技部国际科技合作项目(2009DFA71720)

摘　　要：砂土液化是地震主要次生地质灾害之一。在5.12汶川地震中,德阳等地发生较大面积砂土液化现象。为详细了解液化带工程地质基本特征,选择板桥学校液化带进行详细液化震害调查、钻探和现场试验。结果表明:(1)液化震害典型,主要包括喷水冒砂、地表裂缝、侧移和基础下沉等;(2)砾石层是唯一的无粘性土层,砾石层分为性质不同的全新世沉积和更新世沉积两部分,未见砂层分布;(3)液化土层是全新统砾石层,该砾石的颗粒大小分布特征表现为级配不良,并有粒组缺失现象;(4)非液化盖层对喷出物有过滤作用,砂粒等细颗粒容易沿裂缝喷出地表,卵砾石等粗颗粒受阻留在土层中,导致喷出物为砂土。Liquefaction is one of the most popular secondary geological disasters in an earthquake.Phenomenon of sand liquefaction was found in the Deyang area in the Wenchuan earthquake.The liquefaction-induced disaster investigation and geotechnical engineering drilling and tests were conducted for the Banqiao School liquefaction zone in order to understand the characteristics of engineering geology.The results indicate that（1） Characteristics of liquefaction-induced disaster was typical,including sand boiling,ground fissure and sidesway,foundation settlement.（2） Gravelly sand,which was divided into the Holocene sediment and the Pleistocene sediment,was the only cohesionless soil which had potential to liquefy in liquefaction size.（3） Real liquefaction soil is gravelly sand layer which is the unconsolidated Holocene sediment.Its graduation is poor.（4） The thicker non-liquefaction cover coat has filtering effect so that the small particles such as sand grains is easy to eject out of ground from fissures and,by comparison,the coarse particles such as gravel particles is difficult to spray.

关 键 词：板桥学校液化带 砾石 颗粒大小分布 喷出物 

分 类 号：P642.139[天文地球—工程地质学]