Silting risk assessment method for deep sewage conveying tunnel

Abstract

The invention discloses a silting risk assessment method for a deep sewage conveying tunnel, which comprises the following steps: step A, obtaining a flow velocity process line and an SS concentration process line of the sewage conveying tunnel by adopting an SWMM hydrodynamic model and an SS convective diffusion model; b, calculating the deposition thickness of the pipeline; c, formulating a silting risk weight table; d, according to the SWMM hydrodynamic model of the sewage conveying tunnel and the deposition thickness, the pipeline flow velocity and the SS concentration calculated by the deposition model, inquiring a deposition risk weight table, and obtaining the risk levels of the three risk items; and e, finally, calculating the silting risk value of the deep tunnel according to the risk levels and the weight assignments of the three types of risk items. The method needs fewer parameters, is high in calculation speed, does not need historical desilting data support, can be suitable for a special application scene of the sewage deep tunnel, evaluates the pipe section with higher silting risk in the operation of the sewage deep tunnel, and guides the deep tunnel water diversion desilting work to be carried out in a targeted manner.

Description

technical field [0001] The invention relates to the technical field of simulation and prediction of sedimentation risk in drainage pipes, in particular to a method for evaluating sedimentation risk based on SWMM technology in the scene of deep sewage transportation tunnels. Background technique [0002] At present, urban drainage pipe network is the key point of urban water environment governance. Sedimentation of the drainage pipe network reduces the capacity of the pipes, which leads to problems such as high water level operation of the pipes and frequent overflows during the rainy season. Sediments in the drainage pipe network in the rainy season mainly come from the particulate matter in the sewage in the dry season, as well as the accumulated dust, sand and other particulate matter on the ground in sunny days, which enter the drainage system with surface runoff in rainy days. Therefore, predicting and simulating the sedimentation of drainage pipes is of great significa...

AI Technical Summary

Problems solved by technology

[0003] 1) With the help of the water level test of the upstream and downstream inspection wells, based on the hydraulic model, the situation of the sedimentation pipeline is simulated and predicted through the head loss of the upstream and downstream. This method cannot judge the specific location of the sedimentation between the two inspection wells, and for deep sewage tunnel In special application scenarios such as, if the distance between two inspection wells is too far, the evaluation cannot be performed

[0004] 2) With the aid of Infoworks, the Achers-White model is used to establish a hydraulic water quality load data model based on statistical principles based on existing operating data, and to describe volatility through mathematical characteristic values ​​such as mean value, variance, and probability density function. This model requires a large number of Fitting work lacks consideration of pipeline status and incoming water quality fluctuations, and the applicable scenarios are limited

This method is not sensitive to flow rate changes, and has many parameters, requiring a large number of experimental calibrations, so the simulation results deviate from the actual

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