Research On The Detection Evaluation And Repair Technology Of Rectangular Drainage Pipeline Structure

Reinforced concrete rectangular pipe structure,widely used in water supply and drainage projects in municipal construction.The rectangular pipe inspection evaluation and repair technology theory cash lags far behind the theory of round pipe,rectangular pipe maintenance technology is developed on the basis of round pipe maintenance technology,the two are related and have a certain difference,the difference between rectangular pipe and round pipe is mainly manifested in the qualitative analysis of the pipe,defect condition evaluation,pipe soil effect and other aspects.However,the current field of inspection,evaluation and repair of drainage pipes is mostly for round pipes,and the method of inspection,evaluation and repair of rectangular pipes is not mature,especially in the design of defect evaluation and repair of rectangular pipes.This paper mainly studies the problems in the detection evaluation and repair of rectangular drainage pipes:(1)firstly,we discuss the rectangular pipe appearance quality detection method and rectangular pipe structural performance detection method,analyze their applicable conditions and detection characteristics,and carry out numerical simulation to verify the feasibility of the micro-deformation detection method,according to these two types of detection methods,we divide the pipe evaluation into pipe appearance evaluation and pipe structural evaluation,and briefly describe the two evaluation method systems.(2)Use fuzzy mathematical methods to evaluate the appearance quality of rectangular pipelines,and propose a fuzzy comprehensive evaluation method to improve the current pipeline defect assessment norms,the method first fuzzy grading of pipeline defects,so that the scoring gradient of defects is more moderate,better reflect the degree of defects;then according to the sealing,structural and functional aspects of the defects are weighted separately;finally combined with the importance of the index for comprehensive evaluation of pipeline sections.(3)The structural evaluation of pipelines is carried out using two limit state theories.First,by discussing the soil load model of pipelines,the load situation of buried pipelines under different models is analyzed,and the applicable conditions of each model are analyzed;then the parameters needed for pipeline evaluation are integrated,and the basis for failurediscrimination between the extreme bent and sheared states of pipelines is deduced from the relevant specifications;finally,a limit state theory that considers the separation of reinforcement and concrete is proposed,and the calculation of the structural evaluation of pipelines is simplified by considering the contribution of both to the carrying capacity.(4)Summarized the technical method of non-excavated rectangular pipe repair,and analyzed a set of technical theories from the principle to the wall thickness design to the construction of the cushion lining method to repair box culverts on the basis of existing theories.The design theory of liner method for repairing pipeline is proposed,and the selection method of liner wall thickness is discussed,starting from the shear stress damage and bending damage of rectangular pipeline,the formula is deduced for the grout layer wall thickness of rectangular pipeline;through the analysis of five and river box culvert liner method repair cases,the whole liner method construction process is introduced,and the difference between the liner method repair box culvert and repair round pipe construction process is analyzed.