长江科学院院报2017，Vol.34Issue(10)：85-90,94,7.DOI:10.11988/ckyyb.20160693
白鹤滩水电站柱状节理玄武岩卸荷损伤数值试验研究
Numerical Study on Unloading Damage of Columnar Jointed Basalt at Baihetan Hydropower Station
摘要
Abstract
Unloading damage characteristics of columnar jointed basalt was obvious at Baihetan hydropower station.In the aim of obtaining the unloading damage law of this special rock mass,deformation and strength tests were both conducted to obtain the quantitative expressions of columnar joint's stiffness and strength during unloading test,and then a numerical calculation method in consideration of unloading damage was proposed in association with element method.On this basis,a discrete element numerical model of columnar jointed basalt was established for the research of damage law of columnar jointed basalt during excavation-induced unloading.Results revealed that in the process of unloading parameter decreasing from 6.0 MPa to 1.0 MPa,vertical and horizontal elastic moduli reduced by 64.8％ and 86.3％,respectively,cohesive forces in the two directions reduced by 18.3％ and 46.1％,respectively,and angles of internal friction decreased by 8.4％ and 64.7％,respectively.In other words,the unloading damage characteristics of columnar jointed basalt was significant,and the deformation and strength parameters both reduced remarkably during unloading and the reduction was more serious in horizontal direction than that in vertical direction.The study results could be taken as reference for selecting excavation types and supporting forms in similar projects.关键词
白鹤滩水电站/柱状节理岩体/卸荷损伤/原位试验/离散元法/各向异性Key words
Baihetan hydropower station/columnar jointed rock mass/unloading damage/in-situ test/discrete element method/anisotropy分类
天文与地球科学引用本文复制引用
倪卫达,石安池..白鹤滩水电站柱状节理玄武岩卸荷损伤数值试验研究[J].长江科学院院报,2017,34(10):85-90,94,7.基金项目
国家自然科学基金项目(41572279) （41572279）
湖北省自然科学基金项目(2014CFB901) （2014CFB901）
