Study On Application Of Digital Image Technology In Detection Of Exposed Aggregate Cement Concrete Pavement

Exposed Aggregate Cement Concrete Pavement improves the ordinary concrete pavement disadvantages of skid resistance, driving noise, and glare etc. EACCP broadens the application field of cement concrete pavement. As for the normal cement concrete pavement, EACCP surface has an abundant of micro and macro structures. Dealing with its surface is also relatively complex. Its surface quality plays a decisive role in the performance of road using. This paper tries to use the digital image technology to evaluate the EACCP surface quality by analyzing the processing of EACCP surface image. In the image acquisition methods, image information and the relation of texture depth in pavement, exposed-aggregate particle separation and identification technology, the evaluation indexes and methods of distribution uniformity in the EACCP surface and etc, the theoretical analysis and research in depth is conducted.This paper, by analyzing the theoretical basis about the texture depth detection in pavement through the digital image technology, summarizes that all kinds of external factors may influence on the image analysis in the process of image acquisition. On the basis of this, the standardization image acquisition method is put forward and the quality of the image acquisition has been improved, which lay a better foundation for the further image analysis. After calibration, cutting, smooth processing the collected image, the relation between the EACCP surface image information and the texture depth measured really through the sanding method is simulated through the BP neural network. Different scale networks are trained by using different training methods and the relation model conformed to the certain accuracy requirement is gained by conducting the error analysis on the gained network model.As for the problems on the obviously comparison between exposed-aggregate particle and background and the uneven brightness probably existing in the EACCP image, ideal results are obtained by using the block-combination OTSU segmentation method. The exposed-aggregate particle information in the EACCP surface is extracted through the digital image technology to calculate and analyze the number, acreage and static moment etc. The method that the measured surface exposed-aggregate particle number and the variation coefficient of area percentage are made as double indexes to evaluate the uniformity in the EACCP surface is raised. The concept and calculation method of the pavement uniformity situation index PUI is proposed through draw lessons in the highway technical condition evaluation system from the related specification and the uniformity evaluation system in the EACCP surface is consummated.The programming design for applying digital image technology to the methods of the texture depth test and exposed-aggregate surface uniformity detection evaluation is conducted under the platform of MATLAB programming design. Using GUI design tool integrates its function into a graphical interface which is easily understand and manipulated. The graphical interface is applied for the surface quality detection and evaluation in the EACCP testing road in the Lidu town, Fuling area of Chongqing, which verifies the evaluation method of the texture depth measurement and the surface uniformity evaluation in the EACCP through digital image technology and the adaptability of the gra PUIcal interface.