摘要
二叠系下统栖霞+茅口组灰岩通常风化程度低、强度高,但白鹤滩水电站旱谷地料场灰岩却出现工程性状弱化现象。为揭示白鹤滩水电站旱谷地料场灰岩工程性状弱化特征及成因,通过对料场及周边地质环境调查,结合钻探、声波测试、室内试验等手段可得:旱谷地料场灰岩弱化后强度仅为新鲜岩体强度的1/2~1/4;料场区弱化岩体可分为强风化带、弱风化带上段、裂隙构造带、溶蚀带;分别分布在泥质含量较高的灰岩透镜体和灰白色灰岩夹泥质微晶灰岩条带、地表P 1 q+m-①层、裂隙构造密集带、岩溶溶蚀带;料场灰岩弱化是受灰岩物质成分、构造挤压、岩溶溶蚀作用和风化耦合作用而成。
Limestone of Qixia+Maokou formation of lower permian is usually with low weathering and high strength,while the limestone in Hangoudi quarry of Baihetan hydropower station appeares weakened engineering shape.In order to reveal its weakening characteristics and causes,detail field investigations,drilling,acoustic testing and laboratory tests were adopted.The results show that the strength of limestone in Hangudi site after weakening is only one half to one quarter of the strength of fresh rock mass,the weakened rock mass in material field area can be divided into strong weathering zone and weak zone.The middle section of the chemical zone,the fracture structural zone and the dissolution zone are separately distributed in the limestone sac with high argillaceous content and the limestone with argillaceous microcrystalline limestone strip,the P 1 q+m-①layer on the surface,fractured structure dense belt and the karst dissolution zone.The weakening of the limestone in the material field is caused by the composition of the limestone,tectonic compression,karst dissolution and weathering.
作者
洪望兵
李翔
唐鸣发
黎佳
HONG Wang-bing;LI Xiang;TANG Ming-fa;LI Jia(Powerchina Huadong Engineering Corporation Limited,Hangzhou 310014,China;State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China)
出处
《科学技术与工程》
北大核心
2019年第24期68-75,共8页
Science Technology and Engineering
基金
国家重点研发计划项目(2017YFC1501000)资助
关键词
旱谷地
灰岩弱化
分布特征
控制因素
Hangudi quarry
weakened limestone
distribution features
control factors
