Abstract:Research purposes: Black cotton soil is a special soil existed on a large area of Ethiopia and some other African countries, with dark gray or taupe color. Locally known as black cotton soil generally, the soil has expansibility. Currently, a large number of Chinese companies enter into survey,design and construction market in Ethiopia, but few of them do research on black cotton soil. Therefore,it is necessary to study a set of survey methods suitable for the country's national conditions since there is no existing experience which can be provided to follow, to identify engineering properties of black cotton soil, which can be provided as basic information when we choose appropriate engineering measures for railway projects.
Research conclusions: (1) Black cotton soil has engineering properties like medium-strong expansion, medium-high compression, etc. (2) It proposes the following subgrade treatment measures: strengthening the subgrade drainage system; when cut slope height , 3 m,using shrub and grass for slope protection; when cut slope height>3m, using skeletons protective slope to protect side slope; if the slope is high, set retaining walls; cutting subgrade bottom layer with weak-medium expansive soil shall have replacement no less than 0.5m,cutting subgrade bottom layer with medium-strong expansive soil shall have replacement no less than 1m.(3)It provides guidance and reference for survey and design work of railways, highways, light rail transit construction in Ethiopia.
徐正宣,唐林,张昆,何小军,侯伟龙. 埃塞俄比亚铁路黑棉土勘察方法及工程特性研究[J]. 铁道工程学报, 2014, 31(2): 15-18.
XU Zheng-xuan, TANG Lin, ZHAGN Kun, HE Xiao-jun, HOU Wei-long. Research on Survey Methods and Engineering Properties of Black Cotton Soil of Ethiopian Railway. 铁道工程学报, 2014, 31(2): 15-18.
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