Construction Method of Multiple Casings for Bridge Pile in Areas Facilitated by Karst Cave Development

Abstract

Disclosed are a multi-casing structure capable of facilitating the bridge-pile construction in cavern development areas and a construction method thereof. The multi-casing structure is characterized in that the thicknesses of steel plates of casings are computed through material mechanics formulas; the length of an internal casing is spliced into the designed depth of the pile foundation of a bridge-pile according to the thicknesses of required steel plates; the length of an external first casing is spliced into the distribution depth of an underground cavern though a plurality of groups of steel casings; and the diameters of the casings are designed into that the inner diameter of the internal casing is equal to the designed pile diameter of the bridge-pile and the diameter of the external first casing is 25-35 centimeters larger the designed pile diameter of the bridge-pile during a dual-casing construction. The construction method comprises transporting every groups of the casings to the position of a pile hole though a 25-ton crane; hoisting a first group of the casing to settle through a 60-ton main crane; penetrating a steel bar manually and placing a steel casing on a #-shaped frame; changing slings; hoisting a second group of the casing; subjecting the pile hole to welding; subjecting the steel casing to a second assembly; hoisting the steel casing up lightly; and disassembling the steel bar to enable the steel casing to settle. Therefore, the problem of severe over-quantity of concrete of the bridge-pile construction in the cavern overdevelopment areas is completely solved, and the construction cost can be effectively controlled under the premise of guaranteeing the construction quality and the construction security.

Description

technical field [0001] The invention relates to the construction technology of bridge pile foundations, in particular to a method for constructing bridge piles in areas where karst caves are developed by adopting multiple casings. Background technique [0002] In recent years, with the continuous development of transportation infrastructure construction, there are more and more opportunities to build bridges on the banks of rivers and lakes in areas where karst caves are developed in the south. In the case of many karst caves and underground rivers found in the underground geology, when the pile foundation of the bridge pier is constructed according to the traditional construction technology, the pile holes that are impacted will often collapse, the drilling rig will tilt, and even the hammer head will be buried. burying and other major safety accidents; when pouring reinforced concrete for pile foundations under bridge piers, once underground rivers or underground karst cav...

AI Technical Summary

Problems solved by technology

[0002] In recent years, with the continuous development of transportation infrastructure construction, there are more and more opportunities to build bridges on the banks of rivers and lakes in areas where karst caves are developed in the south. In the case of many karst caves and underground rivers found in the underground geology, when the pile foundation of the bridge pier is constructed according to the traditional construction technology, the pile holes that are impacted will often collapse, the drilling rig will tilt, and even the hammer head will be buried. burying and other major safety accidents; when pouring reinforced concrete for pile foundations under bridge piers, once underground rivers or underground karst caves are encountered, the amount of concrete used cannot be calculated, and the construction cost of bridge piers will increase exponentially. Construction in this environment, Project quality, safety, construction period, and cost cannot be guaranteed, which will cause huge losses to the construction company and affect the overall completion of the entire project.

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