Bridge static load test method based on environmental excitation

Abstract

The invention discloses a bridge static load test method based on environmental excitation. The method comprises the steps: establishing a bridge finite element model according to a bridge completiondrawing, and extracting a centralized mass matrix of a bridge from the bridge finite element model; designing a load test scheme and an acceleration sensor arrangement scheme according to related specifications and the actual state of the bridge; acquiring vibration acceleration response of the bridge under environmental excitation by using an acceleration sensor arranged on the bridge; identifying basic modal parameters of the bridge through a modal identification method; calculating a mass normalized vibration mode scaling coefficient of the bridge structure by utilizing the concentrated mass matrix extracted by the bridge finite element model and the identified bridge basic modal parameters; and then performing quality normalization on the actually-measured vibration mode, calculating an actually-measured flexibility matrix of the bridge by utilizing the normalized vibration mode, further predicting modal deflection of the bridge under the working condition of the static load test,comparing the modal deflection with theoretically-calculated deflection, calculating a static load test verification coefficient and judging the bearing capacity of the bridge. The method is convenient to operate, and traffic does not need to be closed.

Description

technical field [0001] The invention relates to a bridge static load test method based on environment excitation, and belongs to the technical field of bridge bearing capacity detection. Background technique [0002] At present, my country continues to increase investment in infrastructure, and bridge construction has entered a period of rapid development. As my country's transportation industry presents the development trend of modern transportation structures such as heavy load, fast speed, and large flow, the load pressure on highway bridges continues to increase, coupled with the influence of factors such as rain and snow erosion, sun freeze-thaw, etc., seriously affecting function and safety of the bridge. Defects of bridges in operation will result in insufficient functions and be forced to repair or lower vehicle traffic standards, which will affect the traffic of the line and bring huge economic losses. Therefore, how to accurately and quickly assess the structural ...

AI Technical Summary

Problems solved by technology

However, due to the high requirements of the impact excitation on the impact device and the need to interrupt the traffic, its application in practical engineering is limited.

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