Remote monitoring system and method for fatigue cracks of orthotropic steel bridge deck slab

Abstract

The invention provides a remote monitoring system and method for fatigue cracks of an orthotropic steel bridge deck slab. The remote monitoring system for the fatigue cracks of the orthotropic steel bridge deck slab comprises an in-situ detection device, a wireless gateway and a remote control device, wherein the in-situ detection device is composed of a fracture line assembly, a path detector and a wireless terminal, the wireless gateway is composed of a Zigbee gateway module and a GPRS gateway module, the remote control device is composed of a remote server and a remote computer, the fracture line assembly is composed of optical fibers or resistance fracture lines which are arranged in a bidirectional and orthorhombic mode, the path detector is connected with the facture line assembly and used for detecting the connection and disconnection of each fracture line in the fracture line assembly according to a command of the wireless terminal, a Zigbee short-distance wireless transmission network is formed between the Zigbee gateway module and the wireless terminal, and the GPRS gateway module is in remote communication with the remote server through an GPRS. By the adoption of the remote monitoring system and method for the fatigue cracks of the orthotropic steel bridge deck slab, long-term remote monitoring of the fatigue cracks of the orthotropic steel bridge deck slab is achieved, and the system and method can be applied to practical engineering.

Description

technical field [0001] The invention relates to the technical field of steel structure monitoring, in particular to a remote monitoring system and method for fatigue cracks of orthotropic steel bridge decks. Background technique [0002] Orthotropic steel bridge decks are widely used in large and medium-span bridge structures due to their light weight, high overall efficiency, strong spanning capacity, and good seismic performance. However, due to the complex structural stress, difficult control of welding defects, and direct bearing of vehicle dynamics, the orthotropic steel bridge deck is also the most prone to fatigue damage in steel bridge structures. Since the first discovery of fatigue cracks in the structural details of steel bridge decks in the British Severn Bridge in 1971, there have been reports of fatigue cracks in steel bridge decks in Germany, France, Japan, the United States, the Netherlands and other countries. my country's Humen Bridge, Haicang Bridge, Jiang...

AI Technical Summary

Problems solved by technology

There are many limitations in the visual inspection method. For example, on-site conditions may make it difficult or even impossible for inspectors to reach some sensitive areas of fatigue cracking, and manual visual inspection may not be able to accurately determine the tip position of the crack, etc.

Therefore, there are also some steel structure crack detection equipment developed by the principles of electric potential energy drop and ultrasonic return transmission, which can realize accurate measurement of crack size, but these equipment also require manual on-site operation, and there may be some areas that cannot be reached and operated. The problem of limited space, and it is impossible to realize automatic detection and long-term monitoring through remote control

Regardless of the method, it is necessary to manually find the initial location of crack initiation, which is undoubtedly a huge workload for orthotropic steel bridge decks that contain a large number of possible crack locations (ie weld joint areas)

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