Open-cut rock anchoring combined basic and inverse work construction method thereof

Abstract

The invention relates to the technical field of bridge construction, in particular to an open-cut rock anchoring combined foundation and an inverse work construction method thereof. A convex rock exposed out of a river bottom is removed, and a foundation pit is dug; the foundation pit is bound with a steel bar net, a positioning sleeve is pre-buried in the steel bar net, and an open-cut cushion cap is cast on the bound steel bar net; on the open-cut cushion cap, holes are drilled to a bedrock at the bottom of the open-cut cushion cap through the positioning sleeve, and construction of anchoring holes is completed; anchor rods are inserted into all the anchoring holes along the positioning sleeve, anchor rod mortar is injected in the anchoring hole, and anchoring of the anchor rods is achieved; pier stud stressed main bars are welded to the anchoring rods of the corresponding positions of the open-cut cushion cap, a stud body steel bar cage is bounded, and pier body concrete construction is conducted; after the pier body construction is completed, the foundation pit is refilled with concrete till the ground line is reached, and construction is completed. The positioning sleeve is arranged in the open-cut cushion cap, after positioning is conducted through the positioning sleeve, the anchoring holes are drilled, the inverse work construction method of the open-cut rock anchoring combined foundation is easier compared with a method in which drilling and pilling are directly conducted on the bedrock, and the phenomenon like hole broadening is not prone to occurring.

Description

technical field [0001] The invention relates to the technical field of bridge construction, in particular to an open-cut rock-bolt composite foundation and a reverse operation construction method thereof. Background technique [0002] In bridge engineering, open cut foundation is the most commonly used construction method when the geological bearing capacity is good and the foundation bearing capacity exceeds 350Kpa. Especially in the strata where the bedrock is exposed, the open-cut foundation is more economical than the pile foundation, and the construction is convenient. When the bedrock is exposed in the water, and the open cut foundation in the water is disturbed by construction, it is particularly easy to be washed by the water flow, resulting in voids under the foundation and a decrease in stability, threatening the safety of the structure. Or when the bedrock on the half-hillside is exposed, the expanded foundation is adopted, and its ability to resist horizontal la...

AI Technical Summary

Problems solved by technology

If the pile foundation scheme is adopted, since the holes are drilled directly on the hard rock, the drilling is difficult and easy to expand, and the foundation needs to be supported by piles, which requires high strength of the piles, and the foundation is not easy to construct

However, embedding the open-cut foundation in a deeper bedrock will cost a lot in terms of cost and construction period.

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