A buffer method and device for transient pore water pressure of railway subgrade

Abstract

The invention provides a buffer method for transient excess pore water pressure of a railway subgrade. A buffer device is arranged in the subgrade, loading is achieved and subgrade dynamic effective stress is delivered through a rigid device, and the dynamic excess pore water pressure of the subgrade is buffered by a flexible device. According to the buffer method, the two processes of the increase and decrease of the transient excess pore water pressure are considered, and so the problem of mud-pumping of the subgrade is solved from source. The invention further provides a buffer device, which includes the rigid device and the flexible device. An internal cavity is formed in the rigid device, and water holes, which are placed at the surface of the rigid device, communicate with the internal cavity. Through the water holes, pore water flowing into or out the internal cavity is realized. The flexible device is mounted in the internal cavity, and flexible deformation of the flexible device according to changes of excess pore water pressure is achieved. Through the rigid device, the stability of the subgrade is ensured by the buffer device; through the flexible device, buffering the dynamic excess pore water pressure of the subgrade is realized; and the flexible device is installed in the internal cavity of the rigid device, so the flexible device is protected.

Description

technical field [0001] The invention relates to the technical field of railway roadbeds, in particular to a method and device for buffering transient pore water pressure of railway roadbeds. Background technique [0002] For the transient pore water pressure of the railway subgrade, the traditional treatment method is mainly to prevent and control, that is, to reduce the transient pore water pressure of the subgrade by strengthening the drainage and water isolation of the subgrade water. The specific measures mainly include: On the one hand, Improve the permeability inside the roadbed and speed up the water discharge rate inside the roadbed; on the other hand, grouting in the diseased area of ​​the roadbed to block the infiltration of rainwater. For example, Chinese patent CN201710351724 discloses a method for treating the mud and mud of the slab ballastless track railway roadbed. The treatment method is to prevent water from seeping into the foundation bed through grouting,...

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Problems solved by technology

Secondly, the grouting layer itself must have good water resistance, and on the one hand, the grouting layer must overcome the cyclic extrusion and suction of dynamic pore water pressure; on the other hand, it must bear the cyclic effective stress of the soil skeleton. The pulp material has high requirements, and it is difficult to guarantee its long-term strength

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