A method for predicting the safety of surrounding building pile foundations pulled down by blasting demolition of dangerous bridges

Abstract

The invention relates to a method for predicting pulling down safety of a surrounding building pile base by blasting demolition of a dangerous bridge. The safety prediction method of the pull-down ofthe surrounding building pile base due to the dangerous bridge demolition blasting comprises the steps that bridge floor height H<0>, bridge floor width b, pier height H and bridge floor density rho are obtained; the bridge floor quality m per unit width is obtained according to the bridge floor height, the bridge floor width and the bridge floor density; the velocity v when the bridge floor contacts the ground is obtained; the largest impact load p<max> when the bridge floor contacts the ground is obtained according to the bridge floor quality, the velocity when the bridge floor contacts theground and the bridge floor width; the pull-down stress sigma<z> in the surrounding building pile base after the bridge floor contacts the ground is obtained; the pull-down load Q<n> generated by thesurrounding building pile base after the bridge floor contacts the ground is obtained according to the pull-down stress sigma<z>; the single pile vertical ultimate bearing capacity Q is obtained; and the pull-down safety coefficient SF is obtained according to the single pile vertical ultimate bearing capacity Q. The safety prediction method of the pull-down of the surrounding building pilebase due to the dangerous bridge demolition blasting has the advantages that the structure is simple, flow path performance is high, and using is convenient.

Description

technical field [0001] The invention relates to the field of foundation construction, in particular to a method for predicting the safety of surrounding building pile foundations pulled down by blasting demolition of dangerous bridges. Background technique [0002] When urban bridges reach the designed service life or the safety of the bridge structure does not meet the requirements, demolition by blasting is a quick and low-cost method. However, houses are often densely populated around dangerous bridges in cities. When the blasting demolition bridge deck hits the ground, it will have a huge impact on the ground and generate a lot of pressure. When it is larger, it will cause the pile foundation to sink, threatening the safety of surrounding buildings. However, the pull-down load on the surrounding pile foundation and its safety when the bridge deck touches the ground are mostly based on engineering experience, and there is no prediction method in this regard. Contents o...

AI Technical Summary

Problems solved by technology

However, houses are often densely populated around dangerous bridges in cities. When the blasting demolition bridge deck hits the ground, it will have a huge impact on the ground and generate a lot of pressure. When it is large, it will cause the pile foundation to sink, threatening the safety of surrounding buildings

However, the pull-down load on the surrounding pile foundation and its safety when the bridge deck touches the ground are mostly based on engineering experience, and there is no prediction method in this regard

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