混凝土-PE结合U形衬砌渠道抗冻性能探究

Research on Frost Resistance of Concrete-PE U-Shaped Lining Channel

为克服传统预制U形混凝土衬砌渠道过早开裂和渠基土冻胀作用下发生的严重冻胀破坏问题,提出了混凝土-PE结合U形衬砌渠道,使用有限元数值模拟的方法,该结构将渠道分为两部分,将混凝土与PE结合,渠道上部分冻胀荷载较小的部位使用预制混凝土板,渠道下部分冻胀荷载较大的部位使用PE。将渠道下部分PE高度与渠道上部分混凝土高度之间的比值定义为PE相对使用量,以PE相对使用量为变量,探究了混凝土-PE结合U形衬砌渠道的应变、最大位移以及开裂荷载、破坏荷载随PE相对使用量变化而变化的趋势。有限元数值模拟结果表明,随着PE相对使用量增大,混凝土-PE结合U形衬砌渠道的应变、最大位移均增大;当α≥1.50时,衬砌渠道通过发生较大的位移变形,渠道开裂荷载和破坏荷载均大于预制U形混凝土衬砌,能够提高衬砌渠道的抗冻胀能力。

In order to overcome the traditional precast U-shaped concrete lining channel premature cracking and canal base soil frost heave occurred under the action of frost heave damage problems,concrete-PE combination of U-shaped lining channel is put forward.The finite element numerical simulation method is used.The structure of the channel can be divided into two parts;the concrete and PE are combined.The precast concrete board is used in part of frost heave on channel load of smaller parts.PE is used for the part under the channel with large frost heaving load.The ratio between the height of part PE under the channel and the height of part concrete above the channel was defined as the relative use amount of PE(A),and the variation trend of the strain,maximum displacement,cracking load and failure load of the concrete-PE combined with U-shaped lining channel with the change of the relative use amount of PE was explored.The finite element numerical simulation results show that the strain and maximum displacement of the concrete-PE U-shaped lining channel increase with the increase of PE relative usage.When α≥1.50,large displacement and deformation occur in the lined channel,and the cracking load and failure load of the channel are greater than those of the precast U-shaped concrete lining,which can improve the anti-frost heaving capacity of the lined channel.