HDPE排水管道抗冲刷能力与设计流速研究

Study on HDPE pipes anti-scouring capability and its design flow rate

选取不同流速水流对HDPE管道进行冲刷磨损试验,单独研究了管道的冲刷磨损量与冲刷时间和冲刷流速的关系。结果表明经1 000h冲刷后,9m/s、6.4m/s、4.5m/s水流对HDPE管道冲刷磨损量分别为0.239mm、0.116mm、0.090mm。根据重庆地区近10年降雨资料,不考虑管道自然老化等因素时,设计流速为9 m/s、7 m/s、5 m/s条件下拟合计算得到20年时间里雨水对HDPE管道的冲刷磨损量分别为3.634 mm、3.118 mm、2.976 mm。为充分发挥抗冲刷能力可将HDPE管道的设计流速定为9m/s。

An experiment on the HDPE pipe erosion by different water flow velocities was carried out to study the relationship among pipe erosion, scouring time and water flow velocity. The results showed after 1 000 hours scouring time, the HDPE pipe erosion depths made by the water flow velocities of 9 m/s, 6.4 m/s and 4.5 m/s were 0. 239 mm, 0. 116 mm and 0. 090 mm, respectively. Based on the 10 years rain fall datas in Chongqing area and without consideration of the natural aging, the fitting calculation showed that when the design flow velocities were 9 m/s, 7 m/s and 5 m/s, the 20 years rainfall erosion depths on HDPE pipe were 3. 634 mm, 3. 118 mm and 2. 976 mm, respectively. To make best use of the anti-scouring capability of HDPE pipe, the design flow velocity should be 9 m/s.