Construction method of pipe curtain method supporting structure

Abstract

The invention relates to a construction method of a pipe curtain method supporting structure. The method comprises the steps of construction of a waterproof curtain and construction of a pipe curtain;the waterproof curtain is used for water stop and slurry prevention; the pipe curtain is used for grouting to consolidate surrounding rocks above an excavation outline to form a bearing arch; an expansive soil modifying and reinforcing agent is injected into a grouting steel pipe of the pipe curtain; and the expansive soil modifying and reinforcing agent flows out of a grouting hole in the grouting steel pipe and permeates into a surrounding soil layer, so that the surrounding soil layer is modified, the shear strength of expansive soil is improved, the free expansion rate of the expansive soil is reduced, and the supporting effect is improved on the premise of reducing the use of the steel pipe. The construction method in the invention effectively combines the modification of the expansive soil and the pipe curtain method, so that effective support for engineering and long-term prevention and control of later-period stability can be achieved.

Description

technical field [0001] The invention belongs to the field of road and bridge construction, and in particular relates to a construction method for a pipe-curtain method support structure in expansive soil layers. Background technique [0002] In the process of underground engineering construction, special soil layers and landforms such as loess, expansive soil, and sandy soil are often encountered. Due to the particularity of the soil layer, the construction has brought great difficulties, and a large-area pipe curtain structure is usually used. For support, the pipe curtain freezing method is often used for construction in water-rich strata, but in the actual construction process, most of the projects are in unsaturated strata, and these strata cannot have enough pore water to form sufficient freezing wall, and the freezing equipment is relatively complicated, which greatly increases the project cost, and the construction of large-scale pipe screens is a huge challenge for t...

AI Technical Summary

Problems solved by technology

[0002] In the process of underground engineering construction, special soil layers and landforms such as loess, expansive soil, and sandy soil are often encountered. Due to the particularity of the soil layer, the construction has brought great difficulties, and a large-area pipe curtain structure is usually used. For support, the pipe curtain freezing method is often used for construction in water-rich strata, but in the actual construction process, most of the projects are in unsaturated strata, and these strata cannot have enough pore water to form sufficient freezing wall, and the freezing equipment is relatively complicated, which greatly increases the project cost, and the construction of large-scale pipe screens is a huge challenge for the jacking equipment and related support measures, and the engineering cost is extremely high, which still needs strong support in the later stage to maintain The stability of the project, so for this kind of engineering problems, there are quite a lot of methods in the improvement process of the pipe curtain method, but none of them can effectively solve the problem