埃塞俄比亚玄武岩残积土工程特性初探

摘要

Research purposes: Combined Ethiopia light rail transmit investigation project (phase one), the stratum lithology characteristics and physical and mechanical properties of basalt residual soil is analyzed by the comprehensive methods of mapping, exploration and laboratory tests. Comparison of domestic usual measures and local construction experience, engineering schemes of basalt residual soil are provided preliminarily.rnResearch conclusions: (1) Basalt residual soil is different from granite residual soil and common cohesive soil.rnLaboratory test result shows that it has some special traits such as smaller natural density, larger water content and voidrnratio, the free expansion rate greatly changes. (2) It is better to take many methods, such as in - site, laboratory testrnand engineering prospect, to make geotechnical analysis and evaluation of basalt residual soil in field investigationrnprocessing. (3) Chinese codes can be referred during investigation, but it can not be directly used, the localrngeotechnical investigation data, engineering experiences and methods should be collected in construction period.rn(4) This research results can be applicated for investigation of geotecnical engineering of metro and light rail transit inrnigneous area.%研究目的:结合埃塞俄比亚轻轨(一期)工程,通过测绘、勘探及室内试验综合勘察手段,全面了解玄武岩残积土地层岩性特征及物理力学性质,并对比国内工程做法及当地施工经验,探究玄武岩残积土的工程处理方案.研究结论:(1)玄武岩残积土不同于花岗岩残积土及一般黏性土,具有天然密度小、含水量大、孔隙比大、自由膨胀率、离散性较大等特性；(2)现场勘察宜采用原位测试、室内试验及工程物探等多种手段；(3)对玄武岩残积土进行岩土工程分析与评价可参照国内规范,但不宜照搬,施工中应搜集当地岩土勘察资料,借鉴其工程经验及做法；(4)该研究成果可应用于火成岩地区地下铁道及轻轨交通的岩土工程勘察.