Grouting reinforcement method of dam foundation rock mass

Abstract

The invention discloses a grouting reinforcement method of a dam foundation rock mass. The grouting reinforcement method of the dam foundation rock mass comprises the following steps that a hollow pile is prefabricated, specifically, the hollow pile is prefabricated in a factory, a through hole is concentrically formed in the hollow pile, and grout outlet holes are formed in the outer circle of the hollow pile at intervals in the height direction; a reinforcing cage is fabricated, specifically, the cylindrical reinforcing cage is fabricated in the factory or a construction site; drilling is carried out, specifically, the drilling is carried out at a dam foundation to obtain a pile hole; assembling is carried out, specifically, the reinforcing cage is lifted into the pile hole; and grouting is carried out, specifically, high-pressure expanded concrete is poured inward through the through hole of the hollow pile, so that the expanded concrete overflows from the grout outlet holes, and part of the expanded concrete penetrates into gaps of the inner wall of the pile hole. According to the grouting reinforcement method of the dam foundation rock mass, the prefabricated hollow pile is specially designed, and through the cooperation of the hollow pile and the reinforcing cage, a composite pile body is obtained by utilizing the cast-in-situ expanded concrete, and thus the integrity of the composite pile body and the dam foundation rock mass is strengthened.

Description

technical field [0001] The invention relates to the technical field of geotechnical engineering, in particular to a grouting reinforcement method for dam foundation rock mass. Background technique [0002] Concrete high dams (such as gravity dams, arch dams, etc.) are built directly on the rock foundation, and the rock-soil mass of the dam foundation is prone to vertical and horizontal displacements under the action of the dam body's own weight and various load combinations. If the dam foundation is a rock mass with a weak or fractured structure, the rock mass of the dam foundation will often sink vertically due to the compression of pores or cracks in the rock mass. Once subsidence occurs, the stress conditions of the dam body will change, resulting in The dam body is partially unstable or even completely destroyed, so the integrity of the dam foundation is crucial to the safety of the dam body. [0003] When the dam foundation rock mass fails to meet the bearing capacity ...

AI Technical Summary

Problems solved by technology

[0004] (1) Excavating broken rock mass, this method is the most reliable, and can be used for small-scale areas, but for large-scale dam foundation sites, this method will undoubtedly greatly increase the amount of work, and is not economically feasible;

[0005] (2) Use cast-in-situ piles to improve the bearing capacity of the bedrock. This method requires less investment, but since it is necessary to bind steel bars on site, then pour concrete, and vibrate and maintain after pouring concrete, the process is cumbersome, and the underground The pile body adopts the cast-in-place construction method, which is inconvenient to vibrate, and it is difficult to ensure the construction quality of the pile body