• Journal of Wetlands Research
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• v.19 no.1
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• pp.63-68
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• 2017

Maintenance of sewer pipe process sewer pipe repairing process is necessary for deterioration of sewer pipe. In this research, analysis on performance (strength and twist strain) of eco-friendly and even expanded liner process using glass fiber and twist prevention band. As a results, tensile strength, bending strength and failure load is increased after the sewer pipe repairing process than advanced research results. And sewer pipe after the this process obtained advantage of prevention of twist strain and economic. After the this research, sewer pipe repairing process using glass fiber and twist prevention band could be suggest the eco-friendly and effective sewer pipe repairing process.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.1
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• pp.53-62
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• 2006

This study was carried out to obtain quantities of infiltration, inflow and exfiltration on sewer pipes of three areas at a small city. From the results, the most investigated sewer pipes should be infiltrated by underground water and undetermined water. Flowrate commonly showed two peak at 6 to 8 a.m. and 6 to 9 p.m. and which may be influenced by the sewer flowrate with washing or bathing time. BOD/TN ratio of below 4.0 were inferior as compared with proper criteria 5.1. Infiltration/inflow rates of three areas were 21.7% and $0.08m^3/km$ of A, 12.4% and $0.015m^3/km$ of B, 22.4% and $0.021m^3/km$ of C, respectively. This indicates that infiltration/inflow rate of A was obviously greater than that of B and C. Also, these results show that we can conduct sewer maintenance in good order as A, C and B zone.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.5
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• pp.119-128
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• 2008

Sewer rehabilitation is performed to improve the problem for urban drainage sewer system recently. However the data for the sewer system is not stored enough so that the sewer system is difficult to be managed systematically. In this study, a maintenance management system for urban drainage system is developed to store the data efficiently and manage the system systematically. In the developed system, a hydraulic and hydrologic analysis module is included to test the carrying capacity of a sewer pipe and estimate the amount of combined sewer overflows. The I/I and superannuation evaluation module is included in this system. The module distribute the total inflow/infiltration observed at the several sampling points in a drainage area to the individual pipes of the entire sewer system. Then the superannuation of a sewer pipe is evaluated according to the amount of I/I of the pipe. And in the developed system, the optimal rehabilitation priority module is included to determine the optimal priority and support the decision making for the sewer rehabilitation. The maintenance management system which is developed in this study is constructed by the association with the developed modules and the system is formed as graphical user interface system.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.1
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• pp.123-129
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• 2012

A septic tank is a purification treatment system where night soil and other waste matter is converted into harmless material by the activities of bacteria. Effluent from the septic tank flows into the sewer pipe, and then this effluent affects the quality of water environment and makes foul smell. In this study, through the proper maintenance of septic tank it was tried to minimize the impact of sewer pipe on water quality and fouling smell. BOD removal rate from the septic tank's effluent which exceeded legal cleaning period was investigated for the proper maintenance. BOD Removal rate of the twelve septic tank's effluent is -62.5% to 43.9%. According to the result of BOD removal rate, septic tank cleaning should be done at least once a year. And the pathogenic coliform bacillus in the twelve septic tank's effluent is average 768,000 (MPN/$100m{\ell}$). The chlorine disinfection is needed to remove the pathogenic coliform bacillus in septic tank effluent.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.509-517
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• 2020

Geographic information system (GIS) sewer network data are a fundamental input material for urban inundation modeling, which is important to reduce the increasing damages from urban inundation due to climate change. However, the essential attributes of the data built by a local government are often missing because the purpose of building the data is the maintenance of the sewer system. Inconsistent simplification and supplementation of the sewer network data made by individual researchers may increase the uncertainty of flood simulations and influence the inundation analysis results. Therefore, it is necessary to develop a basic algorithm to convert the GIS-based sewage network data into input data that can be used for inundation simulations in consistent way. In this study, the format of GIS-based sewer network data for a watershed near the Sadang Station in Seoul and the Oncheon River Basin in Busan was investigated, and a missing data supplementing algorithm was developed. The missing data such as diameter, location, elevation of pipes and manholes were assumed following a consistent rule, which was developed referring to government documents, previous studies, and average data. The developed algorithm will contribute to minimizing the uncertainty of sewer network data in an urban inundation analysis by excluding the subjective judgment of individual researchers.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.2D
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• pp.147-157
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• 2012

Recent studies on development of level of service (LoS) for separated sewer pipe have simply shown high-level of LoS from the perspective of users and financial/social/economical factors, which results in poor connectivity to real maintenance work. The objective of this study is to develope the evaluation indicators of level of service in the manner of function by analyzing the separated sewer pipes with FAST, function analysis systems technique, used in value engineering. The evaluation indicators suggested in this study include all the functions of separated sewer pipes and show an advantage of focused function maintenance. Moreover, developed indicators help to manage archival history and to perform asset management effectively.

• Journal of the Korean Geotechnical Society
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• v.37 no.12
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• pp.117-125
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• 2021

The occurrence of ground subsidence and sinkhole in downtown areas, which threatens the safety of citizens, has been frequently reported. Among the various mechanisms of a sinkhole, soil erosion through the damaged part of the sewer pipe was found to be the main cause in Seoul. In this study, a random forest model for predicting the occurrence of sinkholes caused by damaged sewer pipes based on sewage pipe information was trained using the information on the sewage pipe and the locations of the sinkhole occurrence case in Seoul. The random forest model showed excellent performance in the prediction of sinkhole occurrence after the optimization of its hyperparameters. In addition, it was confirmed that the sewage pipe length, elevation above sea level, slope, depth of landfill, and the risk of ground subsidence were affected in the order of sewage pipe information used as input variables. The results of this study are expected to be used as basic data for the preparation of a sinkhole susceptibility map and the establishment of an underground cavity exploration plan and a sewage pipe maintenance plan.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.3
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• pp.177-190
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• 2019

The purpose of this study was to analyze the effects of sewerage facilities through I/I analysis by rainfall by selecting areas where storm overflow diverging chamber is remained due to the non-maintenance drainage equipment when the sewerage system was reconstructed as a separate sewer system. Research has shown that wet weather flow(WWF) increased from 106.2% to 154.8% compared to dry weather flow(DWF) in intercepting sewers, and that the WWF increased from 122.4% to 257.6% in comparison to DWF in storm overflow diverging chamber. As a result, owing to storm overflow diverging chamber of partially separate sewer system with untreated tributary of sewage treatment plant, rainfall-derived infiltration/inflow(RDII) has been analyzed 2.7 times higher than the areas without storm overflow diverging chamber. Meanwhile, infiltration quantity of this study area was relatively higher than that of other study areas. Therefore, it is necessary to reduce infiltration quantity through sewer pipe maintenance nearby river. Drainage equipment maintenance should be performed not to operate storm overflow diverging chamber in order to handle the appropriate sewage treatment plant capacity for rainfall because it is also expected that RDII due to rain will occur after maintenance. In conclusion, it is necessary to recognize aRDII(allowance of rainfall-derived infiltration/inflow) and to be reflected it on sewage treatment plant capacity because aRDII can occur even after maintenance to the complete separate sewer system.

• Magazine of the Korea Concrete Institute
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• v.18 no.2 s.91
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• pp.34-39
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• 2006

• Journal of Korean Society of Water and Wastewater
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• v.28 no.4
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• pp.491-500
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• 2014

Due to rapid urbanization and industrialization, water supply and sewer line systems are also developed relevantly. Manhole is an essential component structure of the pipeline system. Manhole is a structure constructed to accommodate the direction, dimension, differences in level, and easy of maintenance in the pipeline system. In this paper we present the result of investigations pertaining to the structural behavior of PVC sewer manhole buried underground. In the paper mechanical properties of PVC material are reported. In addition, by the finite element analysis (FEA), we confirmed that a PVC double-wall corrugated pipe manhole, when it is buried underground, is safe for the stress as well as buckling strength if the manhole is constructed within the suggested limit of buried depth.