阳泉市城市配水管材的比选

阐述了配水管材费用在管道工程总投资中所占的比例较大，以阳泉市城市配水管材的比选为例，经技术经济比较，确定了适合做城市配水管网的管材。     

A review of data-driven approaches for burst detection in water distribution systems

This study focuses on data-driven approaches for burst detection and classifies them into three categories: classification method, prediction-classification method and statistical method. The performance of these methods is discussed. By analysing uncertainty in burst detection, this paper revealed that non-stationary monitoring data and limitations present in these methods challenge the reliability of detection results. Data pre-processing and probabilistic solutions to deal with the uncertainty are summarised. From these findings and discussions, this paper concludes and recommends that: a) data-driven approaches are promising in real-life burst detection and reducing false alarms is an important issue; b) more comprehensive performance evaluation might be necessary, in particular regarding detectable burst size; c) further research on new methods employing multivariate analysis and a new category based on clustering analysis would be beneficial to tackle uncertainty; d) more focus on the use of pressure data might facilitate burst location and reduce investment in burst detection.     

Evaluation of suitable chlorine bulk-decay models for water distribution systems

Maintaining the chlorine residual is a major disinfection goal for many water distribution systems. A suitable general chlorine bulk-decay model is required for simulation of chlorine profiles in networks to assist disinfection planning/management efficiently. The first-order model is unsuitable due to inaccuracy and inability to represent rechlorination. Three potentially suitable, simple, reactant models were compared. The single-reactant model was found to be unsuitable, as it was inaccurate when restricted to using a single set of invariant parameters. The two-reactant model was more suitable than the variable-rate-coefficient model, although both models were accurate under the same restriction. The two-reactant model was then calibrated against datasets consisting of multiple decay tests for five distinctly different waters. It accurately predicted data reserved for validation over the chlorine concentration range of 0-6 mg/L, using a single set of invariant parameters, and is therefore the simplest, generally suitable model for simulating chlorine profiles in distribution system networks.     

PE给水管道在城市管网中的应用

从PE管的管材价格和特性，介绍了PE管的优越性及PE管的连接方法，并阐述了PE管在城市道路下的综合地沟内、导向钻技术中的应用，提出PE管施工中应注意的问题。     

Identifying determinants of urban water use using data mining approach

This study develops a new approach to quantitatively identify the most important determinants of urban water use. The approach is based on a data mining model called genetic programming (GP), which automatically optimizes the structure of the function and parameters simultaneously. With historical urban water use as the target, the GP model identifies the most relevant factors for 47 cities in northern China. Compared with conventional regressive models, the GP model performs better than the double-log model. The Nash–Sutcliffe model efficiency coefficient (NSE) of the GP model is 0.87, while the NSE of the double-log model is 0.79. According to the results of the case study, urban water use is determined by both socio-economic and natural variables. Total population, service industry indicators, green land area, housing area, water price, and rainfall are the most significant determinants of urban water use. Among them, total population, service industry indicators, and green land area clearly have positive contributions to urban water use, whereas rainfall has a negative impact on urban water use. The impacts of housing area and water price are complex, which implies that these determinants may have different impacts on urban water use in different conditions. The new model and new insights developed in this study could be helpful for urban water management, especially for cities that experience water scarcity.     

管棚与注浆技术在隧道突泥中的应用

针对某隧道在施工中发生的突泥灾害,借助TSP-203超前地质探测仪对掌子面前方的地质条件进行了探测,采用长管棚预支护结合小导管注浆对突泥体及周边围岩进行加固处理,经实际证明此方案对于治理隧道突泥是可行的,为今后在流塑状黏土地质中修建隧道积累了一定的经验。     

Multiobjective optimization of water quality and rechlorination cost in water distribution systems

To comprehensively describe the effect of residual chlorine and disinfection by-products (DBPs) on water quality in water distribution systems (WDS) and optimize rechlorination cost, this study developed a multi-objective optimization model of water quality and rechlorination cost. Firstly, chlorine decay and DBPs formation were simulated using EPANET_MSX. An improved non-dominated sorting genetic algorithm II (NSGA-II) with real code was used to optimize the multiobjective model and Pareto fronts could be obtained under different conditions. The results showed that Pareto fronts obtained by average value were better than those obtained by standard deviation and multiplication. Moreover, with the number of boosters increased, maximum value of water quality increased and rechlorination cost decreased. Wall chlorine decay constants were the most important on Pareto fronts, followed by the number of chlorination nodes, proportional coefficients of trihalomethanes (THMs) generation based on residual chlorine consumption, and THMs concentration.     

城市供水量预测的数学模型

考虑到时间、温度、水价对供水量的影响,建立了城市供水量预测的差分阻滞模型和神经网络模型,并对其预测结果进行了比较.结果表明:各模型都是可行的,且预测精度很高.考虑到用水负荷的从众心理和水价对个体用水量的影响,利用元胞自动机模型对水价与城市供水量之间的关系进行了模拟,模拟结果表明当社会从众心理一定时,水价的调整对供水量的影响有一个最有效的范围.     

企业供水管网震害预测

根据历史震害资料，分析了供水管道震害特点，给出了供水管网的震害划分标准和震害预测模型，并应用于实际企业供水网络的震害分析。     

Biostability analysis for drinking water distribution systems

The ability to limit regrowth in drinking water is referred to as biological stability and depends on the concentration of disinfectant residual and on the concentration of substrate required for the growth of microorganisms. The biostability curve, based on this fundamental concept of biological stability, is a graphical approach to study the two competing effects that determine bacterial regrowth in a distribution system: inactivation due to the presence of a disinfectant, and growth due to the presence of a substrate. Biostability curves are a practical, system specific approach for addressing the problem of bacterial regrowth in distribution systems. This paper presents a standardized algorithm for generating biostability curves and this will enable water utilities to incorporate this approach for their site-specific needs. Using data from pilot scale studies, it was found that this algorithm was applicable to control regrowth of HPC in chlorinated systems where AOC is the growth limiting substrate, and growth of AOB in chloraminated systems, where ammonia is the growth limiting substrate.     

浅谈聚乙烯（PE）管在城市给水管网中的应用

简要介绍了聚乙烯（PE）管的发展历史与应用特点,较为具体的归纳了PE管在市政给水工程领域的应用（敷设）形式,并结合实例总结了PE管应用中的几点体会,为给水管网的正常运行提供了保障。     

在给水工程中管材的选用问题

本文就塑料给水管与传统给水管材在特性方面的比较,给出了UPVC给水管在施工中的技术要求。     

给水工程中供水管材的选用

介绍了供水管材的种类,对管材的综合性能进行了比较,探讨了管材的选择原则,提出了选择管材的建议,指出只有对运行工况环境条件、施工条件、经济条件等多种因素进行综合比较和分析,才能最终合理确定选用何种管材。     

Segment identification in water distribution systems

This paper presents a new method for identifying the segments that are formed after the installation and closure of isolation valves in a water distribution network. This method is able to identify segments also when one-way devices are installed in the network. Thanks to its short computing times, the method enables the analysis of real networks which always comprise a large number of nodes and pipes.

The numerical examples presented in this paper refer to two real water distribution networks. The first network is a part of a provincial network where two one-way devices are present; the second is a complex urban network without one-way devices. The method was first used to analyse the existing situation in both networks, i.e. the set of segments that are formed as a consequence of the present valve system. The method was subsequently used for the problem of the hypothetic redesign of the isolation valve system in the second urban network, i.e. the search for the optimal positions of the isolation valves in the network; in the redesign phase it provided solutions which are more cost-effective than the configuration of isolation valves currently present, the level of water service reliability being the same.     

Approximate methods for uncertainty analysis of water distribution systems

Monte Carlo simulation (MCS) has been commonly applied for uncertainty analysis of model predictions. However, when modelling a water distribution system under unsteady conditions, the computational demand of MCS is quite high even for a reasonably sized system. The aim of this study is to evaluate alternative approximation schemes and examine their ability to predict model prediction uncertainty with less computational effort. Here, MCS is compared with a point estimation method, the first-order second-moment (FOSM) method, and a quasi-MCS method, Latin hypercube sampling (LHS). Hydraulic and water quality simulations are performed using EPANET and the evaluated model outputs are nodal pressure, water age and chlorine concentration. Six input parameters, pipe diameter and roughness coefficient, nodal spatial and temporal demands and bulk and wall decay coefficients, are considered. To examine the effect of the magnitude of input uncertainty on model output, three uncertainty levels are evaluated. The study is performed for a real system with 116 pipes and 90 nodes. Results demonstrate that LHS provides very good estimates of the predicted output range for steady and unsteady conditions compared with MCS, while FOSM did well for steady conditions but poorly for some periods in the extended-period simulation for chlorine concentration.     

浅谈PE管在城市给排水工程中的应用

结合工程实例,介绍了给排水系统工程使用管材的种类及各自的特点,分析了PE管材相对其他管材的优点,并对高密度聚乙烯HDPE管在该工程中的选用理由进行了阐述,以推广PE管材在城市给排水工程中的广泛应用。     

室外给水管道安装注意事项

结合给水管道的分类 ,就室外给水管道的安装程序作了阐述 ,从测量放线、开挖土方、管口养护等方面 ,提出了管道安装中的一些注意事项 ,以确保室外给水管道的合理、正常使用     

Contaminant flows in urban residential water systems

A contaminant balance for urban residential water systems has been performed for 12 pollutants. The characteristics of the residential site were based on Ellenbrook, a suburb of Perth, Australia. The sources of contaminants were identified and characterised using published literature values. A water balance was used to estimated flow data, and these results were used in conjunction with the contaminant source characteristics to calculate contaminant loads. The contaminants examined were total nitrogen, ammonia, total phosphorus, copper, zinc, lead, cadmium, suspended solids, dissolved solids, chemical oxygen demand, polycyclic aromatic hydrocarbons and oil and grease. Diagrams of contaminant flows through the water, wastewater and stormwater systems are presented. By identifying the sources of contaminants, the diagrams are a useful reference when considering the fate of contaminants in alternative urban water system configurations or how to better handle or reduce these contaminants.     

厦门市地下管线测量控制网的布设

为保证地下管线成果坐标系统和分幅与城市独立坐标的一致性,同时保证管线位置的精度,建立管线测量控制网是很有必要的。本文主要介绍厦门市管线测量控制网的布设方式、数据处理方法、成果精度和布网的创新点。     

Accounting for uniformly distributed pipe demand in WDN analysis: enhanced GGA

The global gradient algorithm (GGA) is the most widely adopted method for steady-state analysis of water distribution networks. It is used to solve the non-linear system of equations describing mass and energy conservation laws. Nonetheless, it has been recently proved that the usually adopted representation of distributed pipe demands as lumped withdrawals at ending nodes causes inconsistent calibration results and pipe head loss errors which could be non negligible in some network conditions. The original GGA has been contextually modified by introducing a correction of pipe hydraulic resistance under the assumptions of a friction factor independent from the flow regime. This paper aims at providing researchers and software developers with a general formulation of the GGA which entails both the adoption of any generic monomial head loss formula and pipe hydraulic resistance dependence on flow regime. The results could be easily extended to other methods of network analysis.