Analysis of faulting destruction and water supply pipeline damage from the first mainshock of the February 6,2023 Türkiye earthquake doublet

In 2023,two consecutive earthquakes exceeding a magnitude of 7 occurred in Türkiye,causing severe casualties and economic losses.The damage to critical urban infrastructure and building structures,including highways,railroads,and water supply pipelines,was particularly severe in areas where these structures intersected the seismogenic fault.Critical infrastructure projects that traverse active faults are susceptible to the influence of fault movement,pulse velocity,and ground motions.In this study,we used a unique approach to analyze the acceleration records obtained from the seismic station array(9 strong ground motion stations)located along the East Anatolian Fault(the seismogenic fault of the MW7.8 mainshock of the 2023 Türkiye earthquake doublet).The acceleration records were filtered and integrated to obtain the velocity and displacement time histories.We used the results of an on-site investigation,jointly conducted by China Earthquake Administration and Türkiye’s AFAD,to analyze the distribution of PGA,PGV,and PGD recorded by the strong motion array of the East Anatolian Fault.We found that the maximum horizontal PGA in this earthquake was 3.0 g,and the maximum co-seismic surface displacement caused by the East Anatolian Fault rupture was 6.50 m.As the fault rupture propagated southwest,the velocity pulse caused by the directional effect of the rupture increased gradually,with the maximum PGA reaching 162.3 cm/s.We also discussed the seismic safety of critical infrastructure projects traversing active faults,using two case studies of water supply pipelines in Türkiye that were damaged by earthquakes.We used a three-dimensional finite element model of the PE(polyethylene)water pipeline at the Islahiye State Hospital and fault displacement observations obtained through on-site investigation to analyze pipeline failure mechanisms.We further investigated the effect of the fault-crossing angle on seismic safety of a pipeline,based on our analysis and the failure performance of the large-diameter Thames Water pipeline during the 1999 Kocaeli earthquake.The seismic method of buried pipelines crossing the fault was summarized.

Water hammer protection for diversion systems in front of pumps in long-distance water supply projects

For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention. In this study, a water hammer protection scheme combined with an overflow surge tank and a regulating valve was developed. A mathematical model of the overflow surge tank was developed, and an analytical formula for the height of the overflow surge tank was derived. Furthermore, a practical water supply project was used to evaluate the feasibility of the combined protection scheme and analyze the sensitivity of valve regulation rules. The results showed that the combined protection scheme effectively reduced the height of the surge tank, lessened the difficulties related to construction, and reduced the necessary financial investment for the project. The two-stage closing rule articulated as fast first and then slow could minimize the overflow volume of the surge tank when the power failure occurred, while the two-stage opening rule articulated as slow first and then fast could be more conducive to the safety of the water supply system when the pump started up.

Study on the Technology of Supplying Water Safely by Long-Distance Pipeline

The extensively built long-distance water transmission pipelines have become the main water sources for urban areas. To ensure the reliability and safety of the water supply, from the viewpoint of overall management, it would be necessary to establish a system of information management for the pipeline. The monitoring, calculating and analyzing functions of the system serve to give controlling instructions and safe operating rules to the automatic equipment and technician, making sure the resistance coefficient distribution along the pipeline is reasonable; the hydraulic state transition is smooth when operating conditions change or water supply accidents occur, avoiding the damage of water hammer. This paper covered the composition structures of the information management system of long-distance water transmission pipelines and the functions of the subsystems, and finally elaborated on the approaches and steps of building a mathematics model for the analysis of dynamic hydraulic status.

Research on Leak Location Method of Water Supply Pipeline Based on MVMD

At present,the leakage rate of the water distribution network in China is still high,and the waste of water resources caused by water distribution network leakage is quite serious every year.Therefore,the location of pipeline leakage is of great significance for saving water resources and reducing economic losses.Acoustic emission technology is the most widely used pipeline leak location technology.The traditional non-stationary random signal de-noising method mainly relies on the estimation of noise parameters,ignoring periodic noise and components unrelated to pipeline leakage.Aiming at the above problems,this paper proposes a leak location method for water supply pipelines based on a multivariate variational mode decomposition algorithm.This method combines the two parameters of the energy loss coefficient and the correlation coefficient between adjacent modes,and adaptively determines the decomposition mode number K according to the characteristics of the signal itself.According to the correlation coefficient,the effective component is selected to reconstruct the signal and the cross-correlation time delay is estimated to determine the location of the pipeline leakage point.The experimental results show that this method has higher accuracy than the cross-correlation method based on VMD and the cross-correlation method based on EMD,and the average relative positioning error is less than 2.2%.

Landslide Zoning in Amir-Almoemenin (AS) Water Supply Pipeline Complex, North Khorasan

Landslide term is used for all mass movements on slopes, including falling, overturns and flow debris. Using the potential landslide hazard zonation, areas with high potential of landslide hazard can be detected and so prevent the landslide occurrence with providing appropriate solutions. In this study, the landslide hazard zonation along the water transmission lines of the Amir-Almomenin (AS) water supply complex has been done. Studied area is located at the western part of the Northern Khorasan (Bojnord). Study procedure includes the general geology survey, recognition of the most important effective parameters on the landslide phenomena (such as slope, lithology, faults and streams) and has been evaluated as basic maps. Then, each layer was validated based on the importance of the effective factors using the maps weighting method in ArcGis software. Finally, the studied area was zoned based on the landslide potential using the overlapping of the various layers. Final zonation map shows that the North, Northwestern and Median parts of the studied area have the highest landslide potential. These areas are included of Marl and red Marl and to some extend loss deposits with slopes between 14 to more of 50 degrees. Seemingly, faults (due to low occurrence) and streams (due to drought) have lower effect on the landslide potential. However, the degree of the slope and type of lithology are the most important parameters on the landslide potential, respectively.

Complex Sequence Quality Evaluation Model for Concealed Water Supply Pipeline of Prefabricated Construction

The accurate assessment of the quality can materially affect the safety and life of the prefabricated construction.In this paper,we studied the overall module of concealed water supply pipeline,and a new complex sequence quality evaluation model was established.By analyzing the small evaluation index elements of the model,the weight of the larger evaluation index could be deduced.The total quality evaluation score of the overall module could be obtained by calculating the weight value of the evaluation index,and then the quality standard of the overall module could be obtained.

积石山6.2级地震供水系统震害调查与分析

2023年12月18日甘肃省积石山县发生6.2级地震,造成当地各类工程结构发生不同程度的破坏,导致了重大人员伤亡。基于调查资料,总结了供水系统中的建(构)筑物、设施设备和供水管网的震害特征。研究表明:经过正规抗震设计和施工的建筑物震害较轻,表明我国抗震设计规范发挥了积极作用;低烈度区水厂设施设备因地震破坏而停运,个别设备漏油污染了水质,进而导致了供水能力下降;位于高烈度区的供水管网在老旧钢质管道连接处发生多处破坏,出现了水量不足、水压降低的情况,给居民生活造成了不利影响。最后,从采取设备减隔震技术、管道和设备接口采用柔性连接、选择供水管道材质、全面开展管网漏损排查等四个方面提出了恢复重建的建议。

透析用水内毒素指标与供水管路使用寿命的探讨

目的通过分析透析用水内毒素检测指标探讨供水管路的维护方法及更换周期。方法调查某透析中心使用10年以上的供水管路内毒素检测指标,根据供水管路使用现状、水处理系统日常维护流程,分析透析用水内毒素超标原因,并探讨透析用水内毒素相关防控策略。结果2022年4月15日发现反渗水出口内毒素含量为0.096 EU/ml、反渗水回口内毒素含量为0.156 EU/ml,予以消毒、冲洗等干预措施后未达标,更换反渗膜后反渗水出口内毒素含量为0.022 EU/ml、反渗水回口内毒素含量为0.036 EU/ml;2022年9月内毒素指标又出现异常,对供水管路进行消毒后发现反渗膜出口内毒素含量为1.025 EU/ml,反渗膜回口内毒素含量为2.012 EU/ml,整体更换供水管路后内毒素指标恢复正常值。结论加强透析用水供水管路的日常监管及维护,可降低透析用水内毒素超标风险,确保患者透析安全。

大型变电站消防栓给水管道断裂原因

某大型变电站消防栓给水管道发生断裂。采用宏观观察、化学成分分析、扫描电镜分析、金相检验、力学性能测试及强度校核计算等方法对管道断裂的原因进行分析。结果表明:管道沟槽接头的滚槽工艺不当,使管道内壁沟槽边缘出现严重的机械损伤,破坏了基体的连续性,并产生较大的应力集中;管道组织中存在大量游离态渗碳体,使材料脆化,降低了材料的抗滚压加工开裂能力;管道及沟槽接头装配不规范,在管道与弯头连接的卡箍边缘形成了较大的弯曲力矩,内壁机械损伤部位萌生裂纹并扩展,最终导致管道断裂。

不锈钢内衬法修复供水管道所需内衬管厚度分析

不锈钢内衬法修复供水管道目前缺乏专用的技术规范与完善的设计理论,特别是关于不锈钢内衬管的厚度设计方面存在较大争议。对不锈钢内衬管的破坏模式进行了分析,提出了不同破坏模式下的内衬管厚度计算公式,并通过案例对比了不同破坏准则下所需的不锈钢内衬管厚度的相对大小。结果表明,《城镇给水管道非开挖修复更新工程技术规程》(CJJ/T 244)设计的内衬管厚度偏于保守,宜按承受内压、负压和局部孔洞下的跨越能力共同约束条件设计不锈钢内衬管的厚度。

基于管道易损性的供水管网震后服务功能研究

为研究不同管道易损性公式下供水管网的震后服务功能差异,提出一种评估震后管网服务功能的方法。首先,结合不同管材的特性,对比分析4种基于经验统计的管道易损性公式的管道震害率差异;其次,基于蒙特卡洛模拟方法,随机生成管道地震震害信息;再次,利用MATLAB软件构建震后供水管网模型;然后,以供水满足率为震后服务功能指标,通过压力驱动水力分析得到管网及节点的平均供水满足率;最后,以2个不同规模、不同管材占比的实际管网为例,对管网的平均震害率及震后服务功能进行对比分析。结果表明:不同公式计算得出的平均震害率与地震烈度有关;不同管材的管道长度占比影响管网的平均震害率;管网的震后服务功能不仅与管道震害率有关,同时与管网本身的规模、拓扑结构和密度相关。

不锈钢供水管材的土壤外腐蚀特性试验

试验以砖红壤中Cl^(-)和含水率为研究要素,借助电化学工作站,开展3种不锈钢供水管材(304、304L、316L)外腐蚀试验。结果表明:3种不锈钢在不同Clˉ和含水率的砖红壤中均有不同程度腐蚀倾向(304>304L>316L);当砖红壤Clˉ质量分数在10~1 250 mg/kg时,3种不锈钢腐蚀电流增幅(ΔI_(corr低))较大,为304L>316L>304,当Cl_(ˉ)质量分数在1 250~2 500 mg/kg时,其Δ_(Icorr高)较小,为304L>304>316L,即腐蚀减缓,Clˉ在一定范围内促进不锈钢管材腐蚀。与此同时,当砖红壤含水率在5%~35%时,3种不锈钢ΔI_(corr)为304L>316L>304,其中,当含水率在15%~25%时,其ΔI_(corr中)较大,为304L>316L>304,即腐蚀加快,含水率在一定范围内使不锈钢管材腐蚀加快。

供水管网系统中DOM解析与DBPs生成特征

为保障城市供水安全,实现南方某市优质饮用水入户,通过对目前供水管网水质情况进行调查分析,明确供水管网系统中溶解性有机物(DOM)在不同季节、余氯及停留时间等参数条件下对消毒副产物(DBPs)生成情况的影响。研究表明:供水管网系统中常规水质指标如浑浊度、余氯和溶解性有机物主要取决于出厂水的浓度,供水管网中余氯变化较大,在管道中进行补氯有利于提升供水管网中不利点的居民饮用水安全。紫外和荧光光谱分析方法在供水管道中检测方便、检测限较低且不受其他工艺影响且检测浓度较低,可有效指示供水管道中存在的异常风险。三氯甲烷与卤乙酸是供水管网系统中主要存在的DBPs,其生成受到出厂水水质、管道、管道距离及季节性等多因素的影响,在供水管线中的含量变为随管线距离增长而增大;在温度较高的季节DBPs生成浓度高、反应速度快,应受到重点关注。

市政给排水管道布置的设计原则与技术分析

为了提升市政给排水设计水平,总结了给排水管道布置的基本原则和设计目标,分析了排水体制、雨水设计流量、污水设计流量的确定方法,从技术和经济两方面对比了不同给排水管道材料。同时,分析了给排水管道的纵向和横向布局方法,研究成果表明市政给排水管道竖向布局应控制好管道埋置深度和交叉方式,横向布局方式应根据地形和道路条件选择确定。

供水管道内腐蚀鉴定技术与模拟方法研究进展

内腐蚀是引起供水管道漏损、缩径以及水质恶化的重要原因之一。针对上述问题,文中从物理、化学和生物3个角度出发,梳理了供水管道内腐蚀的成因和过程。同时,将内腐蚀鉴定归纳总结为:依据内腐蚀现状形态的直接鉴定法,以及依据内腐蚀导致的运行影响的间接鉴定法。此外,对管道内腐蚀研究中包括实物模拟、机理等效模拟和计算模拟等研究方法进行汇总,最终提出了未来在内腐蚀鉴定和模拟方法的技术展望。

现有供水管道冰浆冲洗技术应用案例分析与探讨

管道冲洗是保证供水安全的重要手段,北京市现状供水管网冲洗时根据现状管线的具体情况,多采用传统单向水冲洗、气水冲洗等管道冲洗技术,确保供水管网水质安全。传统单向水冲洗、气水冲洗技术冲洗管网后,其冲洗效果维持时间短。文中以北京市首次应用冰浆冲洗技术冲洗某市政供水管道为例,详细介绍了被冲洗管道的基本情况,并对管道冰浆冲洗作业流程进行了归纳和总结。通过收集整理和分析管道冰浆冲洗过程中的水质监测数据,对冰浆冲洗效果进行了分析与探讨。冰浆冲洗结果表明,冲洗后管道内壁附着的大量污染物被冲洗排出,管网水浑浊度降低了80.86%,管道内水质达到《生活饮用水卫生标准》(GB 5749—2022)的要求。研究可为其他省市自来水公司管道冲洗提供借鉴和参考。

基于管道节点水龄的供水管网中途加氯优化

节点水龄被认为是评价管网水质的重要参数之一,与余氯浓度之间存在着紧密的关联。如何在漫长的管网输水过程中,维持饮用水的水质安全是一项挑战。通过节点水龄和余氯浓度的关系,基于广度优先搜索思想的拓扑排序算法,按照定义计算节点间水龄,提出并构建节点水龄有效矩阵,并结合遗传算法对中途加氯点和加氯量优化模型进行优化求解。对优化后的实际管网案例进行单时刻静态模拟和多时刻动态延时模拟分析,结果表明,基于节点水龄的供水管网中途加氯优化能够降低节点加氯量的投加,余氯浓度分布更均匀,为给水管网水质优化提供了实际指导。

基于工程实例的市政供水管道健康状态评估技术

市政供水管道在社会循环中起着向用户输送饮用水的职能,对于人们的日常生活和社会发展至关重要。随着供水管网规模不断扩大,管网拓扑结构愈加复杂。目前,政府大力推进老旧管网改造,但仍然存在老旧管网投入运营。近年来,管网漏损、爆管及水质污染等事件频出,管道健康状态评估成为了保障供水安全可靠运行的重要课题,也为老旧管网改造提供依据。传统的管道巡检和手动测量等方法存在精度低、耗时长等局限性。文章中的工程案例依托系缆式管道内检测技术对上海市某区内管段进行健康状态评估,并对该管段内的受损提出了相应的维护建议。

跨孔电阻率法在城市输水管道渗漏监测中的应用

主输水管道在城市中多沿道路埋设,其管径大、埋藏深,渗漏前期不易察觉,渗漏后对城市交通和居民生活影响严重,故对输水管道的渗漏监测尤为重要。城市密集的交通线、硬化路面、电磁干扰等因素限制了地面电法、探地雷达等方法在管道监测中的应用。为弥补现有监测方法的不足,本文开展跨孔电阻率法在管道渗漏监测方面的研究。首先,通过正反演方法对渗漏管道、未渗漏管道进行模拟计算,分析跨孔电阻率法的探测特点。其次,通过试验对电极材质、埋设方法进行分析研究,解决了电极腐蚀、电场信号弱等问题。最后,在北京某处输水管道附近建立试验场,使用跨孔电阻率法获取了多期监测数据,通过对比多期电阻率断面,分析管道渗漏量的变化,圈定渗漏影响范围,得到了水厂渗漏数据的验证,取得了良好的监测效果,可为城市开展类似管道渗漏监测提供借鉴。

曲线吻合度算法在高层住宅小区庭院管道漏损控制中的应用

供水管网作为城镇最重要的基础设施之一,在长期运行中由于种种原因,经常出现漏损现象,尤其是庭院管网暗漏,具有成因复杂、不易察觉、漏失时间长、漏失量大等特点,给供水企业造成不可估量的损失。控制管网漏损率成为供水行业长期以来亟需探讨的课题,而作为“最后一公里”的二次供水的庭院管网漏损往往被水司、物业所忽视。文中提出一种“曲线吻合度”算法,以大数据为基础支撑,利用计算机技术,实现对庭院管网漏损的精准预判。结合某水司3年多的应用实践,证实该算法对漏损事件的预判具有准确性和实用性,为降低庭院管网漏损提供有效的技术支撑。