Papers by Keyword: Bridge Detection

Abstract: First, conducting static load tests for a 5 span bridge, then carry on application research for the bridge based on the embedded carbon fiber (CFRP) reinforced flexural reinforcement aiming at the shortcomings of its flexural properties, At last, the effectiveness of strengthening reinforced concrete beam that reinforcement by embedded CFRP has been discussed. The results show that embedded CFRP reinforcement beam can make full use of the characteristics of high strength of CFRP, which can improved obviously the capacity of the reinforced beam and the maximum increased capacity can reach 13.2%. In addition, the application of the embedded CFRP reinforcement technology has been discussed, which provides a meaningful reference for the development of the technology.

Abstract: Strengthening safety monitoring of bridges during service time and improving the capability of emergency support have become the priority of the development of China’s present transportation system. Strain sensors play a great role in bridge detection and health monitoring system. In order to overcome disadvantages of traditional resistance strain sensors, such as big temperature drift, short life and inadaptability in the environment of low temperature and humidity, new arch strain sensors have been developed. This paper mainly discusses the structural and material characteristics of this sensor, as well as the performance test analysis of this strain sensor.

Abstract: In order to solve the problem of the linear measurement of arch ring for the detection of bridge,a new method is presented that measures the arch ring using a reflectorless total station on the side of the arch bridge and the detail operations are given. Taking account of weakness of edge suveying using a reflectorless total station,some formulas on the 3d coordinates calculation of the above and down edge of the arch ring based on the arch ring points are deduced.According to the law of error propagation, the accuracy of the X and Z axial coordinates are analysed.It is helpful for calculating lateral and vertical deformation and biridges elevation map that the transformation from free-station coordianates to the birdge axis coordinate by programming using EXCEL software is achieved.The method is used for bridges arch ring axial measurement in Qingcheng town,Yuzhong county,Gansu province,and its deformation is consistent with the measured results of the dial indicator,which satisfies the requirement of bridge detecton accuracy.So it is showed that the method is a good way of linear measuring of bridges arch ring.

Abstract: This paper carries out an algorithm research on bridge target detection in SAR images and presents a method that combines both texture features and correlation features. The method firstly extracts initial targets by using the algorithm of histogram equalization segmentation, and then conducts a contrastive analysis for targets and their surrounding background textures by using the gray level co-occurrence matrix to get rid of the false alarm target. The experimental results show that the method is simple, effective and has certain algorithm robustness.

Abstract: An automatic detection algorithm of bridges above water in aerial images is proposed. Firstly, aerial image is binarized based on gradient mean square variance, and binary image is denoised based on pixel density. Then connective areas are labeled in the binary image based on pixels to extract water area. Finally, bridge area is detected based on gray information. Experiments show this algorithm is effective in automatic detection of bridges above water in aerial images.

Abstract: This paper discusses recent nondestructive testing technology in the application of bridge structure, which focus on common rebound method and electromagnetic induction method. According to the actual measurement problems, the article explains the rebound method and electromagnetic induction method including their advantages and disadvantages, and puts forward the method of avoiding problems.

Abstract: This paper is an analysis of buttresses detection after a car crash, with acoustic detector and GRP. It is found no serious affection in the material property which is still of good flexibility. Through a finite element method, a jacking and repairing scheme to jack the single-column bridge of both sides together is chosen. Make use of the Carbon Fiber Reinforced Plastic in the basic crack for reinforcement.

Abstract: Crack inspection of bridges is indispensable to maintain the public traffic safety. It is conventionally carried out by specialists through visual inspection manually. Considering the efficiency and security, digital image processing technique is used to inspect the bridges. After analyzing many representative images of cracks, this paper presents the particular region feature, gray value feature and contour feature of cracks on the bridges’ surface and obtains hundreds of cracks’ feature values. We select some representative data to identify cracks from images according to these cracks’ feature values. The software has been developed to distinguish whether cracks exist in an image, and to extract automatically the existent cracks by means of MATLAB. We present experimental results obtained to prove these methods.