Research Of The Detection Method Based On FRFT Of Bridges Pipeline Grouting Quality And Software Development Of Its Applications

Bridges as a transportation hub, to a large extent affects the development of national economy and progress of our society. Prestressed concrete structures are widely used in bridges construction because of its good mechanical properties and tensile properties. If the pipe grouting is not compacted during the construction process, it will make the pipe bridges of steel bar corrosion, applying prestress will lose effect, thereby service life of the bridges will be shorten. Therefore, the bridges prestressed pipe grouting quality testing is necessary. Stress wave method is a nondestructive testing method for the detection of pipe grouting quality. The bridges pipe grouting structure analysis of stress wave signal is helpful to improve testing solutions and the accuracy of test results. This article applies the fractional Fourier transform(FRFT) to the bridges pipe grouting quality tests. Based on FRFT the detected stress wave signal was analyzed, so as to identify the defects in the structure of bridges pipe grouting. The main research contents and results are as follows:(1) The structure of bridges pipeline grouting in the detection of longitudinal stress potter sexual transmission was studied, and the defect in the structure of bridges pipe grouting was analyzed through the FRFT. First, we should use the finite element software ANSYS/LSDYNA to establish finite element model whose length is respectively 50 mm and 100 mm, 150 mm, 200 mm(full and half empty empty) and are all full bridges of pipe grouting structure. Second, we solve and extract the stress wave signal. Third, by using FRFT processing stress wave signal. Analysis results indicate that with the length of the empty slurry from 0 to 200 mm, namely as the defect is bigger and bigger, the signal in fractional domain amplitude ratio is increasing; when the length is of a certain half road, the signal in fractional domain amplitude ratio is stronger than that when it all escapes.(2) The transverse stress potter sexual transmission and reflection in the structure of bridges pipeline grouting was studied. Moreover, defects in the structure of bridges pipe grouting was analyzed based on the FRFT. First, we should use the finite element software ANSYS/LSDYNA to establish finite element model grouting compactness is respectively 0%, 30%, 50%, 70%, 100%. Second, we solve and extract the stress wave signal. Third, by using FRFT processing stress wave signal. Analysis results show that with the grouting compactness from 0% to 100%, that is, with the defects becoming smaller and smaller, horizontal transmission and reflection signal in fractional domain amplitude ratio is bigger and bigger.(3) Based on FRFT of bridges pipeline grouting compactness detection data processing software development and its applications. The software is designed by Labview, it realizes the call Matlab the FRFT of Labview. By using FRFT processing the detected data of bridges pipe grouting construction, results show that with increasing grouting compactness, stress wave signal in fractional domain amplitude ratio is bigger and bigger, the results which is in conformity with the analysis results of the simulated data. It means that signal in fractional domain amplitude ratio can reflect grouting defects.The study of this essay will make some contributions to the analysis of the data of the grouting defect structure on FRFT.