Method for improving fully-weathered phyllite by compounding red clay and cement

Abstract

The invention relates to a method for improving fully-weathered phyllite by compounding red clay and cement. The method specifically comprises the following steps: adding dry red clay with the mass of m1 and cement with the mass of m2 into fully-weathered phyllite with the mass of m0 for compounding and improving; and forming a C-group filler mixed filler with liquid limit less than 40%, safety factor of real-time ultimate bearing capacity of subgrade surface after rolling compaction beingnot less than 2, settlement less than 15mm and foundation coefficient K30 not less than 130MPa / m, wherein the blending ratio of red clay in the mixed filler ranges from 25.7% to 60%, and the blending ratio of cement in the mixed filler ranges from 3% to 5%. According to the present invention, the optimal blending ratio scheme is provided according to the requirements of common railways and high-speed railways, and the two special soils such as the red clay and the completely-weathered phyllite can be completely utilized, so that the liquid limit and the settlement amount of the completely-weathered phyllite can be reduced, and the safety coefficient of the ultimate bearing capacity and the foundation coefficient K30 can be improved; and the D-group filler is changed into the C-group filler, and the requirements of various indexes of the roadbed can be met.

Description

technical field [0001] The application relates to the technical field of roadbed filler selection and improvement, in particular to a method for compounding red clay and cement to improve fully weathered phyllite. Background technique [0002] Fully weathered phyllite is widely found in the northern part of Jiangxi Province and the northwestern part of Zhejiang Province. There are a large number of them along the Shangrao Kengkou Freight Yard and Branch Project, the Jiujingqu Railway, the Yueji Section of the Menghua Railway, and the Changjiu Railway. Distribution, accompanied by red clay along the line. [0003] (1) Problems with fully weathered phyllite used alone as roadbed filler [0004] When fully weathered phyllite is used as roadbed filler, its liquid limit is as high as 43.3%, which is a high liquid limit soil. According to the "TB 10001-2016 Code for Design of Railway Subgrade", when using a 76g cone and a 10mm liquid limit standard, the cohesive soil with a liqu...

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Problems solved by technology

[0012] The object of the present invention is to provide a method for compounding red clay and cement to improve fully weathered phyllite, which can reduce the liquid limit and settlement of fully weathered phyllite, and improve the safety factor of ultimate bearing capacity and foundation coefficient K 30 , changing group D fillers to group C fillers, overcoming the poor effect of traditional cement improvement on improving immediate bearing capacity and red clay improvement on settlement control and K 30 The improvement effect is not very good, and it can meet the design index requirements of railways, especially high-speed railways

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