Technical Research And Application For Sewer Blockages Identification And Positioning In Rural Areas

With the continuous improvement of China’s infrastructure construction,the sewer network coverage increased significantly,which has played an important role in the improvement of the living conditions.In recent years,the coverage of sewer networks in rural areas has been extended,which brought great convenience to rural living conditions.However,sewers in villages and towns are facing lack of operation,short of maintenance capabilities,garbage crop enter sewers,and insufficient water flow capacity.Consequently,sewage and sediment are trapped and deposited in sewers and lead to blockage and siltation of sewers,affecting sewage discharge and may even causing sewage overflow and causing hidden dangers to public health safety.The existing sewer routine inspection technologies,such as pipeline robots,ultrasound,laser profile analysis and CCTV video surveillance,are mostly used for routine status detection of sewers and fault determination and fault location after pipeline failure,which is difficult to meet the needs of online monitoring and blockage identification and positioning of sewers in rural areas.In view of the problem of blockage and siltation during the operation of sewers in the above-mentioned rural areas,this study focuses on the sewer blockage identification and positioning experimental system,and uses the sewer liquid level monitoring network to obtain the normal operation of sewers and the liquid level change law before and after blockage.Pilot-scale experiments and full-scale experiments and sediment sedimentation simulation experiments of sewers were carried out,and discriminant analysis models and multiple linear regression models were established according to the experimental data,so as to meet the needs of online monitoring and blockage identification and positioning of sewers in rural areas.The experimental results show that after sewer blockage,it can be quickly detected within 8 m upstream to detect obvious liquid level rise,and the liquid level drop phenomenon different from normal liquid level fluctuation can be detected in the downstream range of 60 m,and the sewer blockage identification and positioning matrix is established,the simulation experiment of sediment deposition in sewer shows that sediment deposit is mostly concentrated at the diameter and steering of the sewer.Blockages that are not trapped in the sewer will follow the sewage flow to the grid at the end of the sewer,causing the grid blockage,and the grid level at the minimum flow at night is proportional to its degree of blockage.The results of the prediction group of sewer blockage discriminant analysis model show that the overall success rate of the model for sewer blockage and normal operation is greater than 91%,the success rate of blockage discrimination is greater than 88%,and the positioning accuracy of the sewer blockage regression analysis model shows that the probability of positioning error within 10 m in175 groups of blocking data is greater than or equal to 48%,the probability of error less than 15 m is greater than 70%,the probability of error exceeding 20 m is less than 7%,and the maximum error distance is less than 25 m,and the positioning accuracy is ideal.In this study,the sediment sedimentation simulation experiment of sewer and the liquid level monitoring network of sewer were used to explore the sediment sedimentation law of rural sewers and the change law of liquid level before and after sewer blockage.The success rate of the rural sewer blockage identification model established in this study is 88%,the probability of blockage positioning error less than 15 m is greater than 70%,and the maximum error is less than 25 m,and the blockage positioning accuracy is better than other similar studies.In this study,the sediment sedimentation simulation experiment of sewer and the liquid level monitoring network of sewer were used to explore the sediment sedimentation law of rural sewer and the change law of liquid level before and after sewer blockage.The rural sewer blockage identification and positioning model established in this study has a successful rate and positioning accuracy.Fast and accurate identification and positioning of sewer blockages is the key to ensuring the stable operation of sewers in rural areas,which can reduce unnecessary excavation and save manpower and material resources,and provide engineering reference for the implementation of similar projects in rural areas.In summary,this study can provide technical support for the identification and positioning of sewer blockage in rural areas.