The Development Of Rayleigh Wave Nondestructive Testing System Based On Virtual Instrument Technology

Since the reform and opening-up, construction of infrastructural facilities are carried out comprehensively with vigorous development of Chinese economy.Increasing demand for highway maintenance and testing are increasingly required,which has increasingly higher requirements for quality testing equipment of highway.As studies show, 75% of road damages in China are caused by Water damage.The structures of strong base and weak plane are mostly used in China. Under the influence of expansion and contraction, cracks appear in the structure of road. When water intrude into base and subgrade of road via semi-rigid reflection crack, damages caused by water are happened. With the effects of infiltration of water and car load,dynamic water pressure is produced, mud brought out, so that pumping, pothole, void and other diseases are appearing. Traditional road void detective methods are of subjective initiative, heavy workload. The equipment of Ground Penetrating Radar(GPR) and the falling weight deflectometer(FWD) are expensive, and it is also more expensive of each dispatched to check, the cost is relatively high. In addition to the geological survey of the site of the bridge construction, the traditional methods are drilling exploration, not only high cost, but also time consuming.Therefore, it is very important to develop a fast and non-destructive method in the application of highway detection and geological stratification. On the one hand can rapidly local detection of highway pavement disease and to provide the basis for subsequent maintenance; on the other hand it is convenient and fast to soil geological stratification and cost savings.Based on the virtual instrument technology and the Rayleigh wave prospecting,this study has done the following research:(1) Using the piezoelectric acceleration sensor, USB data acquisition and control module, based on the LabVIEW development platform, build the Rayleigh wave nondestructive testing system that can be carried out on the highway pavementdisease detection and soil geology layer.(2) Using Rayleigh wave nondestructive testing system to detect the road disengaging of Xinyang municipal road. Compared with the test results, the results show that the detection system is accurate and meets the requirements of the project.(3) Using Rayleigh wave nondestructive testing system to detect the road disengaging of Xinye County municipal road in Nanyang City. Through detecting the diseased lane using the test system developed and compared with the adjacent lane with free of disease, the test results are quite different, further proof of the detection system is reliable.(4) Using Rayleigh wave nondestructive testing system to test the bridge construction site geological stratification of Linying County in Luohe city. The test results are compared with the survey results, which meet the requirements of the project, and the nondestructive testing system is stable and reliable.