Study On The Evaluation System Of Concrete Bridge Scene Deck Blasting Based On 3D Image Technology

The blasting technology as a surface disposal has been widely used in concrete bridge,tunnel and old concrete pavement "white and black" transformation in recent years.Blasting disposal can not only eliminate the cement concrete surface laitance and pollutants,can also increase the surface roughness.So as to improve the bonding effect between layers.But the application of blasting technology in road-bridge project in China is still in the early stage.There are no specific specifications and technical requirements for the effect of shot blasting,and there is no technical guidance document for shot blasting construction.Therefore,it is necessary to study the construction technology of shot blasting and the evaluation system of shot blasting effect.This paper is based on the new project of Guangdong Shan-Zhan expressway,by means of field investigation,literature search,field test,mathematical statistics and theoretical analysis,this paper studies the evaluation system of shot blasting on concrete bridge deck.The following work and research results are described as follows:(1)The application of image processing technology in cement concrete bridge deck structure measurement.The paper introduces the measurement principle,characteristics in cement concrete surface structure in the measurement method of the image processing technology,analyzed the processing method and the measured surface characteristics influence on the result of the measurement of light intensity,image acquisition,image distance and angle,and take effective measures on the influencing factors,to ensure the stability and accuracy of measurement results.(2)This paper analyzes and compares the common methods to measure the structural characteristics of cement concrete bridge deck.The characteristics and applicability of various methods are summarized.The method of measuring the structural characteristics of cement concrete surface is determined by the method of manual sanding,pendulum and image processing.Through the analysis of the test data,it is found that the friction coefficient and the gray value have a good correlation.(3)Investigation on the existing market of the shot blasting machine and pill material specifications,applicable range of different types of shot blasting machine and different specifications of pellets,combined with concrete bridge construction characteristics and economic applicability principle,determine the choice of walking type shot blasting machine and steel shot blasting(sand)for disposal of cement concrete bridge deck.According to the working parameters of shot blasting machine,shot blasting scheme design is different,on the cement concrete surface structure characteristics of different blast process after the disposal of measurement,through the analysis of the blasting effect of process parameters on the index value of the situation,determine the economic and reasonable blasting construction technology.(4)On the basis of the design documents,the construction of the cement concrete bridge deck after different shot blasting scheme is adopted.After the specified time,the inter-laminar bond strength test.The correlation between the test results and the evaluation indexes of the bridge structural characteristics is analyzed.Based on the analysis and selection of the indexes which are better correlated with the bond strength between layers,the evaluation indexes of the bridge structural characteristics are obtained.Finally,the statistical analysis of the change of each index before and after shot blasting is carried out.Taking the change of the index value of shot blasting as the standard of shot blasting evaluation.And the statistics of the initial value of each index before blasting in the interval is taken as the acceptance standard of the bridge deck.