In high-rise and ultra-high-rise residential buildings, the drainage systems usually adopt the S-shaped offset pipe joint to avoid collisions of pipelines with beams and columns. However, the flow direction changes at the offset point would significantly affect the drainage capacity of the systems. To better understand the influence of pipe offset joints on the drainage capacity, three different building drainage systems namely YZW 1, YZW 2, and YZW 3 systems, were built up and investigated. YZW 1 system is a standard double-stack drainage system with anti-reflux H-tube joints. YZW 2 and YZW 3 systems were developed from YZW 1 by adding S-shape offset pipe joints on the 4th floor. An extra anti-reflux H-tube joint added 1 m above the offset joint as a measure for improving the drainage capacity differentiates YZW 3 system from YZW 2 system. The pressure fluctuation and water seal losses were adopted as experimental parameters to determine the maximum discharge capacity according to Standard for Capacity Test of Vertical Pipe of the Domestic Residential Drainage System. The experimental results show that the discharge capacity limitation of the drainage system with the offset joint is 6.5 L/s, which is much smaller than 11.0 L/s of the system without the offset joint. In the experiments with the offset joint, the pressure fluctuated fiercely at the position where flow direction changed and caused severe water seal losses of the floor drain and P-shaped trap. An anti-reflux H-tube joint above the original offset joint was observed to relieve the pressure fluctuation as an improvement and the drainage capacity was improved to some extent. The relationships among the maximum discharge rate, pressure fluctuation transients, and water seal losses were discussed. Lastly, a nondimensional analysis was adopted to understand the relationship between water seal losses and pressure limit values under different discharge rates for current test facilities. Practical application: A method has been tested and approved to effectively improve the discharge ability of a building drainage system that includes offset. The application of S-shape-offsets in high-rise building drainage systems can relieve the discharge congestion typically caused by standard pipe offset arrangements.

中文翻译：

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S形弯管安装对高层建筑双排排水系统水流量的影响

在高层和超高层住宅建筑中，排水系统通常采用S形偏置管接头，以避免管道与梁和柱的碰撞。然而，在偏移点处的流向变化将显着影响系统的排水能力。为了更好地理解管错缝对排水能力的影响，建立并研究了三种不同的建筑排水系统，分别为YZW 1，YZW 2和YZW 3系统。YZW 1系统是具有防回流H型管接头的标准双排排水系统。YZW 2和YZW 3系统是从YZW 1开始开发的，方法是在4楼添加S形偏置管接头。YZW 3系统与YZW 2系统的区别在于，在偏置接头上方1 m处增加了一个额外的防回流H型管接头，以提高排水能力。以压力波动和水封损失为实验参数，根据《民用住宅排水系统立式管道能力试验标准》确定最大排放能力。实验结果表明，带偏置接头的排水系统的排量极限为6.5 L / s，远小于不带偏置接头的排水系统的11.0 L / s。在带有偏置接头的实验中，压力在流向改变的位置剧烈波动，并导致地漏和P形疏水阀的严重水封损失。观察到原始偏置接头上方的防回流H型管接头可以缓解压力波动，从而改善了排水能力，并在一定程度上提高了排水能力。讨论了最大排放率，压力波动瞬变和水封损失之间的关系。最后，采用无因次分析来了解当前测试设备在不同排放率下水封损耗与压力极限值之间的关系。实际应用：已经测试并批准了一种方法，可以有效地提高包括偏移量在内的建筑排水系统的排放能力。S形偏移在高层建筑排水系统中的应用可以缓解通常由标准管道偏移布置引起的排放拥堵。采用无量纲分析来了解当前测试设备在不同排放率下水封损耗与压力极限值之间的关系。实际应用：已经测试并批准了一种方法，可以有效地提高包括偏移量在内的建筑排水系统的排放能力。S形偏移在高层建筑排水系统中的应用可以缓解通常由标准管道偏移布置引起的排放拥堵。采用无量纲分析来了解当前测试设备在不同排放率下水封损耗与压力极限值之间的关系。实际应用：已经测试并批准了一种方法，可以有效地提高包括偏移量在内的建筑排水系统的排放能力。S形偏移在高层建筑排水系统中的应用可以缓解通常由标准管道偏移布置引起的排放拥堵。