Gravel pile composite foundation liquefaction resistance distinguishing method based on super-pore water pressure ratio

Abstract

The invention discloses a gravel pile composite foundation liquefaction resistance distinguishing method based on a super-pore water pressure ratio. The method comprises the following steps that by means of the relation between a liquefaction index and the field super-pore water pressure ratio, on the basis of the field super-pore water pressure ratio of the gravel pile composite foundation, an equivalent liquefaction index of the composite foundation is obtained; according to the magnitude of the equivalent liquefaction index of the composite foundation, the liquefaction grade of the gravel pile composite foundation is evaluated according to the existing code for seismic design of buildings, and the problem that only compaction and vibro-compaction effects of a gravel pile are reflected for the distinguishing standard of the standard penetration method of gravel pile composite foundation liquefaction resistance in the existing code for seismic design of buildings is solved; the compaction and vibro-compaction effects, damping effects and drainage pressure reduction effects of the gravel pile are comprehensively considered; in the actual engineering, the distinguishing standard is applied, the design scheme of the gravel pile composite foundation can be more reasonable, foundation processing workloads can be reduced, the construction period can be shortened, the engineering investment can be saved, and the good application prospect is achieved.

Description

technical field [0001] The invention relates to the technical field of civil engineering, in particular to a method for judging anti-liquefaction of gravel pile composite foundation based on excess pore water pressure ratio. Background technique [0002] During the short period of earthquake action, the vibration caused by the earthquake makes the saturated sand tend to be dense, resulting in a sharp increase in pore water pressure; this sharply rising pore water pressure is too late to dissipate, which will reduce the effective stress of the soil; when When the pore water pressure increases to a certain extent and the effective stress decreases to a certain extent, the site soil begins to liquefy from point to surface. With the further increase of pore water pressure and further decrease of effective stress, the liquefaction area continues to expand, The degree of liquefaction of the site continues to increase; when the effective stress completely disappears, all sand parti...

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Problems solved by technology

[0009] The purpose of the present invention is to overcome the problems of anti-liquefaction design based on the existing discrimination standards, increasing the amount of foundation treatment, prolonging the construction period, and increasing the project investment

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