建筑排水系统水封抗正压性能初步实验研究

水封是建筑排水系统的重要组成部分,水封破坏将会严重影响排水系统正常工作。建筑排水系统水封常常会因为正压喷溅、负压抽吸、蒸发、虹吸等遭受破坏,其中正压破坏将会直接把建筑排水管道里的有毒有害气体逸入室内空间,影响人们的生命健康。本文在不同水封容量、不同水封高度、不同水封比的水封装置条件,对建筑排水系统立管内正压对水封的影响进行试验研究,得出了一些定性的结论并针对水封保护提出了一些建设性意见。     

基于疫情防控视角的水封及地漏安全性探讨

建筑排水系统水封安全事关建筑室内环境舒适性与安全性,在传播性疾病爆发的背景下,水封破坏更可带来病原菌随排水系统扩散的不良后果,基于病原菌风险防控角度的排水系统设计优化和水封破坏应对措施仍需深入研究和采取针对性措施,本文基于疫情防控视角,对当前水封安全性及地漏多维参数方面的研究现状和问题进行了分析,提出了进一步应关注和研究的方向,以期为相关研究和实践提供参考。     

建筑排水水封蒸发初步实验研究

水封是建筑排水系统的重要组成部分,水封损失将会严重影响排水系统正常运行和产生不良的后果。而蒸发现象是引起水封损失和破坏的因素之一,如何提高水封可靠性问题越来越受行业的关注,也是当今行业研究的课题。本次实验历时3个多月对不同水封容量、不同水封高度、不同水封比的水封,在不同温度、不同湿度、不同遮盖情况下,对水封静态蒸发损失情况进行测量与分析,有助于提高人们对水封静态蒸发损失的认识。     

市售UPVC存水弯水封存在的问题

在已经投入使用的住宅和公建中，因UPVC存水弯质量问题导致排水管道水封易被破坏的现象不断发生，从而严重影响了室内空气质量。总体上，UPVC存水弯水封破坏有3方面原因：设计、材料和施工问题。其中，成品UPVC存水弯的水封高度大多低于50mm是出现该问题的关键。     

对住宅排水系统有害气体防治措施的探讨

结合排水系统产生的有害气体逸入室内的原因,对水封破坏的原因和保护措施进行了分析,重点探讨了地漏的选择及其水封保护措施,提出隔层排水系统与同层排水系统应该选用不同的地漏形式。     

建筑排水系统水封破坏的动态原因剖析

讨论气压波动破坏建筑排水系统水封。指出气压波动产生的主要原因是排水立管中水流速度大,对横支管产生强烈的抽吸作用,其次是横管排水在立管中产生的水舌阻隔作用。还指出水封破坏的防止措施和建筑排水系统发展的可能趋向。     

高层建筑排水管道系统的排水特性分析

近年来,国内外的高层建筑排水管道系统在技术上有了显著的进步,但是仍然出现超过通水能力的排水现象,导致水封破坏,臭气排入室内,给建筑室内环境带来隐患。因此,本文对高层建筑排水系统的排水特性进行分析,试图解决排水管道通水能力和水封破坏问题,也为高层建筑管道系统排水设计提供技术参数。     

建筑排水系统水封破坏原因分析及应对措施

卫生间空气质量不仅决定人们的感官感受,污染空气还会对使用者的身体产生危害。为了防止排水管道内的臭气溢入室内污染空气,从3个方面分析了目前建筑排水系统水封装置破坏的原因,提出了在设计阶段、安装阶段、使用阶段分别通过合理选择排水通气系统、购买安装合格产品、科学使用卫生洁具等防止水封装置破坏的有效措施。     

基于突变理论的水封储油洞室稳定性分析

据洞室围岩破坏的非线性特点,考虑到储油洞室失稳破坏问题是一种突变问题,运用Hoek-Brown强度折减法及突变理论,得到了洞室围岩强度折减系数与突变特征值的关系,然后根据突变特征值给出了水封储油洞室围岩的稳定性安全系数,最终建立了基于Hoek-Brown强度折减法的水封储油洞室稳定性分析的突变模型,克服了Mohr-Coulomb强度折减法不能描述岩体非线性破坏特征,以及单纯使用强度折减法计算中不能精确量化失稳判别准则的缺点,提高了洞室安全系数模拟计算精度。将本文所建立模型的结果与已有模型的计算结果进行了对比,并利用上述模型分析了洞室埋深、孔隙水压力、洞室间距和蠕变时间等因素对水封储油洞室稳定性的影响。计算结果表明:基于Hoek-Brown强度折减法建立的突变模型具有很好的实用性,可以满足实际工程计算精度要求;水封储油洞室的安全系数随着洞室埋深、孔隙压力、蠕变时间增加而降低,随着内洞室间距的增加而增加。     

卫生器具存水弯水封被破坏的治理

分析卫生器具的存水弯水封破坏的原因 ,提出了排水管道在安装过程中应采取的技术措施 ,并结合卫生器具的使用问题给予综合治理     

建筑排水水封抗负压性能初步研究

水封是建筑排水系统常用的装置,本文通过实验研究,建立水封比,水封液面高度、击穿压力和击穿后水封剩余高度之间相互关系,为合理设计建筑排水系统水封装置提供了可靠依据。     

高承压水上采煤底板突水通道形成的监测与数值模拟

 底板采动破坏及导水通道的形成是底板突水发生的必要条件,也是进行矿井突水的监测预报基础。以新义矿为例,采用现场监测及数值模拟等手段,研究高承压水上采煤底板采动破坏及突水通道的形成及演化过程,分析该过程中的底板电阻率、应力及孔隙水压力的变化规律。结果表明：高承压水上采煤底板受工作面超前支撑压力破坏严重,11011工作面底板破坏深度达到25 m,大于一般经验计算值;建立的基于流–固耦合底板采动破坏数值模拟模型更能准确、客观地反映底板破坏的影响因素,模拟的最大破坏深度为23.75 m,与现场监测结果接近;采动过程中的底板电阻率、应力以及孔隙水压力变化较好地反映底板破坏及突水通道形成、演化以及充水的整个过程,可作为矿井突水临突监测预报的重要信息源。     

沥青路面裂缝特征分析与密封处理方法

水损坏已成为沥青路面最为严重的损坏形式之一,道路裂缝的密封处理对于防止水对道路的侵蚀起着至关重要的作用。针对当前国内沥青路面裂缝病害现状,结合道路养护施工实际情况,本文对沥青路面裂缝病害特征进行了详细分析,并提出了适合不同类型裂缝的密封处理方法,以期有效防止水对道路的侵蚀,降低道路养护成本,延长道路使用寿命。     

液压系统橡胶密封失效的原因分析及预防

通过对液压系统橡胶密封失效的形式,特点的分析,论述了影响密封失效的主要相关因素及预防方法。介绍了几种常用橡胶密封件的使用性能及装配要点。     

分析机械密封失效的原因

列举了机械密封失效的外部现象，分析了产生这些现象的原因，并提出了相应的补救措施，对维修与排除机械密封故障有一定的帮助。     

Detergents in drainage systems for buildings

Current soil waste vent (SWV) system design guides aim to produce ventilated drainage networks for buildings which protect attached water trap seals from unwanted air pressure effects. Such effects may cause trap seal failure that are caused by airflow induction during discharge. The ventilation design guides are based on steady-state experiments utilising cold clean water as a test media. However, most 'grey' and 'black' water sources are dosed with detergent, and are often warm, which significantly alters the behaviour when compared to clean water. Thus, current design standards provide only approximations of SWV system response. Results indicate that induced airflows in warm detergent-dosed water can be significantly higher than those measured in clean water systems, by a factor of more than 2. This paper quantifies the effect of detergents in SWV systems in terms of observed air entrainment rates and previously published research on the factors that contribute to air entrainment. Results of previous work are cast into dimensionless groupings suitable for inclusion into a mathematical simulation model based on a finite difference scheme. It utilises the method of characteristics as a solution technique to simulate drainage system operation via the equations that define unsteady partially filled or full bore pipe flows and the boundary conditions represented by water traps and other common system components.     

梯级泵站串联加压长距离输水的水锤特点及防护措施

远距离输水中的串联加压梯级泵站水锤特性与传统的单级泵站相比有所不同,为此分析了串联加压梯级泵站水锤的各种成因及其过程,提出采取设置带止回装置的旁通管的方式消除因泵站事故引起的高压水锤,采取在管线上间隔0.8 km左右设置一个排气阀的方式消除因事故引起的低压水锤.     

Characteristics of air pressure fluctuations in high-rise drainage stacks

Maximum air pressure in a drainage stack can deplete the appliance water trap seals that prevent the ingress of foul gases and odors into a habitable space. This study investigates the air pressure fluctuation frequency, as well as the maximum and average air pressures with their respective standard deviations, in a 38 m high drainage stack of a full-scale experimental tower under steady flow conditions of flow rates 1 Ls⁻¹ to 4 Ls⁻¹ discharging at a height between 15 m to 33 m above the stack base. Mathematical expressions are proposed to correlate the maximum air pressure with the probability density function of the data measured. The average prediction and the maximum under-prediction of the absolute peak pressure were determined with the margin of error taken within certain confidence levels. It was demonstrated that water seal failure would likely be occurred at some heights below the discharge locations. The outcome enhances the understanding of the characteristics of air pressure fluctuation within a drainage stack of a high-rise building.     

Effectiveness analysis of water-sealing for underground LPG storage

With the developed transient UPNM, numerical simulations are carried out to analyse the seepage field of the underground petroleum storage project in Jingzhou, China. The 3D discrete fracture pipe network model is adopted to systematically analyse the effects of the water curtain system (different water curtain states, water curtain pressure, length and spacing and the angles of the horizontal water curtain system) on the water-sealing effectiveness of the rock caverns in the fractured rock mass in both construction phase and storage phase. Water-sealing performances of different water curtain system schemes with various fracture networks are also discussed. It is found that the effect of the horizontal water curtain is more important than the vertical water curtain. The reducing of the pressure of the water curtain, the length of the water curtain boreholes and the increase of the spacing of the water curtain borehole can deteriorate the seal effect of the water curtain, increase of angles of horizontal water curtain can’t improve water seal. And effective connectivity of fractures is found to be dominant factor to determine water-sealing results. In addition, it is worth mentioning that the fracture network is highly irregular in the flow domain, which greatly influence the seepage field, and the failure of the water seal effect can occur locally. The locally connected unsaturated flow paths have been observed in the study, which cannot be found by using the continuous simulation model. Finally, optimal water curtain system design is recommended. Furthermore, one connectivity evaluation criteria is developed to determine the effectiveness of water-sealing system in the field, according to Lugeon, effectiveness and TEM site test.