Collapsed loess subgrade base treatment method for railway with speed more than 200km

Abstract

The invention discloses a collapsed loess subgrade base treatment method for a railway with speed more than 200km, and belongs to the technical field of railway construction. The collapsed loess subgrade base treatment method for the railway with speed more than 200km comprises the following steps of 1, using two culverts or two bridges as a construction unit; firstly using a cement soil compaction pile to eliminate the collapsibility of the loess on a foundation in a way of first two sides and then middle part and row separation construction; then, adopting a pipe sinking method to form a hole in the cement soil compaction pile; 2, adopting a CFG (cement flyash gravel) pile to reinforce the foundation, wherein the CFG pile is drilled by a long spiral drilling machine; 3, cleaning the soil between the piles, forming a cement bedding layer, testing and checking, and entering the subgrade body filling procedure after qualification is confirmed. The collapsed loess subgrade base treatment method mainly solves the technical problems that the setting requirement is high, the collapsed loess is generally in the saturation state, and the difficulty in control of settling amount is higher after the construction of the subgrade of the railway with speed more than 200km.

Description

technical field [0001] The invention relates to the technical field of railway construction, in particular to a treatment method for railway collapsible loess subgrade base. Background technique [0002] Collapsible loess is formed under arid climate conditions. In the initial stage of formation, a small amount of seasonal rainwater aggregates the loose silt particles, while long-term drought makes the water evaporate continuously, forming a multi-layered loess with coarse silt particles as the main skeleton. Pore ​​Structure. It is characterized by high strength and low compressibility in the natural dry state. Once a large amount of precipitation or channel water infiltrates, various soluble salts in the loess will be dissolved after soaking, and the cementing force in the soil will weaken. Under the joint action of self-weight and a certain load, the soil structure is rapidly destroyed, and the bearing capacity is also sharply reduced, resulting in a large amount of coll...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to: aim at the above existing problems, to provide a method for treating the subgrade of railway collapsible loess subgrades with a speed of more than 200km, which mainly solves the problem of high settlement requirements after the construction of fast railway subgrades with a speed of more than 200km / h, and the collapsible loess It is generally in a saturated state, and it is difficult to control the settlement of the subgrade after construction. A complete set of high-quality, high-efficiency thick-layer collapsible loess subgrade base treatment, subgrade filling and settlement control technology is provided to meet the high construction requirements in Northwest China. Relevant requirements for grade railway subgrade construction and post-construction settlement

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