HDPE板衬砌渠道可行性初探

Preliminary Study on the Feasibility of HDPE Plate Lining Channel

为了分析高密度聚乙烯(HDPE)板衬砌技术在渠道工程中的可行性,使用改性后的HDPE原料或废旧PE滴灌带作为渠道的衬砌板,结合施工方案设计、水力学分析以及冻胀数值模拟对其展开研究。HDPE板采用热熔连接和在渠段连接处设置伸缩孔的施工方案,保证了整体的防渗性能。水力学分析表明:相较于混凝土衬砌渠道,低糙率的HDPE板衬砌可以减小渠道一半的过流面积,间接减小了工程占地面积和工程量。冻胀模拟结果表明:与混凝土板衬砌渠道相比,柔性的HDPE板材料使渠基土的冻胀力得到较大的释放,渠坡板的法向冻胀力和切向冻胀力分别减小51.15%和45.49%,渠底板的法向冻胀力和切向冻胀力分别减小84.22%和85.59%;随着HDPE板厚度减小,渠板位移、法向冻胀力以及切向冻胀力会有略微的增加,但不会发生断裂破坏。综合表明:HDPE板衬砌渠道具有施工方便快捷、防渗性能较好、水力性能优良、抗冻胀效果显著、符合可持续发展理念等特点,此项研究可为寒旱地区梯形渠道工程设计和施工提供参考。

In order to analyze the feasibility of high density polyethylene(HDPE)plate lining technology in channel engineering,the modified HDPE raw materials or waste PE drip irrigation tape were used as the channel lining board,and the research was carried out in combination with construction scheme design,hydraulics analysis and numerical simulation of frost heaving.The HDPE plate adopts the construction scheme of hot-melt connection and setting up the extension and shrinkage hole at the connection of the channel segment,which ensures the overall anti-seepage performance.The hydraulics analysis shows that,compared with concrete lining channels,HDPE plate lining with low roughness can reduce half of the channel's flow area and indirectly reduce the project floor area and amount.The frost heave simulation results show that compared with the concrete slab lining channel,the flexible HDPE slab material can greatly release the frost heaving force of the canal foundation soil.The normal and tangential frost heaving forces of the canal slope slab are reduced by 51.15%and 45.49%respectively,and the normal and tangential frost heaving forces of the canal floor are reduced by 84.22%and 85.59%respectively.With the decrease of HDPE plate thickness,the displacement,normal frost heaving force and tangential frost heaving force of channel plate will increase slightly,but no fracture will occur.The comprehensive results show that HDPE plate lining channel has the characteristics of convenient and quick construction,good anti-seepage performance,excellent hydraulic performance,significant anti-frost swelling effect,and in line with the concept of sustainable development,etc.This research can provide reference for the engineering design and construction of trapezoidal channel in cold and drought areas.