Safety Evaluation Of Water Supply Pipeline Structure

China's buried water supply pipe has steel pipe,cast iron pipe,steel plastic composite pipe and small caliber plastic pipe.Many pipelines are laid at the beginning of urban construction.With the increase of service life,the pipes are aging and so on,which results in serious leakage of the pipe network.At the same time due to interference of city underground engineering construction,such as subway construction,underground tunnel construction,underground pipeline engineering and construction of foundation pit,underground pipe to cause accidents happen frequently,mainly including: the interface Water Leakage pipeline water hammer caused by rupture of plastic pipe,and metal pipeline corrosion and scaling,seriously affect the safety of city water supply system.Therefore,in order to maintain the normal operation of the pipe network and ensure the safe water supply of the city,it is necessary to effectively grasp the status of the pipeline,so as to do a good job in the management of the pipe network.How to dynamically evaluate the status of the water supply pipeline,so as to take appropriate countermeasures to strengthen it is very important.At present,there is not much research on the evaluation software of water supply pipeline according to the situation of our country.Through the pipeline evaluation software,to help pipe network managers to water supply pipe network scientific management.The main research contents of this paper include:(1)Polyethylene pipeline safety criteria from polyethylene pipe strength,deformation and stability of the three aspects discussed the applicability of different failure criteria and parameter calculation model,expected service life,and the factors affecting its safety.(2)Cast iron pipeline safety criterion: the strength,deformation and stability of cast iron pipe three summarizes the failure criteria,model parameters,circumferential and axial stress parameter calculation,considering the effect of ice load,and restrictions on the corner of the interface.(3)Safety criterion of steel pipeline: the failure criterion is summed up from three aspects of strength,deformation and stability of steel pipe,and the calculation model of parameters is discussed.The detailed calculation of the three aspects is carried out with an engineering example,and the practicability of the judgment failure theory is verified.(4)The design of PE and cast iron pipe failure calculation and checking procedure of water supply pipeline structure: the input pipe elastic modulus,deformation modulus,diameter,wall thickNess and depth of overlying soil and other basic data,the calculation model according to the parameters above the corresponding pipe,calculate the pipe stress including circumferential and axial etc.,to verify the practicability of the judgment criterion.The status of the pipeline can be judged by software,and the safety of underground pipelines can be quickly mastered.