Testing device and testing method for recognizing weld defects of orthotropic steel bridge deck slab

Abstract

The invention relates to a testing device and a testing method for recognizing weld defects of an orthotropic steel bridge deck slab. The device comprises a signal generator (1), an acoustic emission transducer (2), a receiving transducer (3), an acceleration sensor (4), a signal amplifier (5), a signal acquisition processing system (6) and a hitting hammer (7), wherein the hitting hammer (7) is used for supplying a low frequency vibration signal to the bridge deck slab (8). The method comprises the following steps: calculating and drawing a straight line relationship graph of side frequency energy and hammering energy by utilizing a non-linear ultrasonic amplitude modulation phenomenon, and judging whether weld defects exist on a U rib of the orthotropic steel bridge deck slab by comparing the change of a straight slope. By utilizing the non-linear ultrasonic characteristics after the defects exist on the bridge deck slab, whether the weld defects exist on the welding position of the U rib of the orthotropic steel bridge deck slab and the bridge deck slab can be effectively recognized, the parts of the defects can be judged, and theories and practical methods are provided for recognizing the weld defects at the U rib of the orthotropic steel bridge deck slab.

Description

technical field [0001] The invention relates to a test device and method for identifying weld defects of orthotropic steel bridge decks. Background technique [0002] Orthotropic decks are increasingly used in long-span and extra-long-span bridges. According to statistics, the welding crack between U-shaped rib and bridge deck is the main damage form of this kind of structure. After the cracks of the orthotropic bridge deck appear at the weld, if they cannot be discovered in time and corresponding remedial measures are not taken, the cracks will develop rapidly under the direct action of the vehicle load, which will greatly increase the maintenance cost, and even serious It affects the performance of bridges and brings great harm to driving safety. Therefore, in order to ensure the safety and reliability of this type of structure, it is necessary to propose a certain method for online identification of weld defects in orthotropic bridge decks, timely evaluation of material...

AI Technical Summary

Problems solved by technology

However, the theory of nonlinear ultrasonic characteristics is not yet mature, and some nonlinear ultrasonic phenomena still cannot be explained, and there are certain limitations in the test methods i

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