衬砌粗糙度对季节冻土区渠基土-衬砌接触面间峰值抗剪强度的影响北大核心CSCD

目前来看,在构筑物与土体表面粗糙度影响土-构筑物接触面间切向冻胀力方面的研究还较少,因此,本研究从川西季节冻土区渠基土-衬砌接触面的切向冻胀力问题出发,着重考虑衬砌表面粗糙度这一因素对接触面间抗剪强度、黏聚力、内摩擦角的影响规律和影响效应,并结合环境温度、含水率及冻结时长,利用正交分析综合探究了4种因素对接触面间峰值抗剪强度影响的相关性和显著性,结果表明:接触面间抗剪强度、黏聚力、内摩擦角随衬砌表面粗糙度变化呈现相同规律,即衬砌表面越粗糙,3项指标随即增大。正交分析中揭示了影响接触面间峰值抗剪强度大小最显著的因素是衬砌粗糙度,其次是环境温度和含水率,冻结时长的影响效应不显著,同时低温、低含水率、较长冻结时长、较高衬砌粗糙程度下的峰值抗剪强度越大。此项结果可为季节冻土区渠系工程防冻胀危害提供理论支撑。

Impact of lining roughness on peak shear strength of soil-lining interface in seasonal frozen zone

Based on predecessors in the soil structure and the surface roughness affect the soil-structure of contact area between the tangential frost heaving force research is less， this study starts from the problem of tangential frost heaving force between soil-lining contact surfaces of canal foundation in western Sichuan seasonal frozen area， and focuses on the influence law and effect of surface roughness of lining on shear strength， cohesion and internal friction angle between contact surfaces. Combined with environmental temperature， moisture content and freezing time， the correlation and aboriginality of four factors on peak shear strength between contact surfaces are comprehensively explored by orthogonal analysis. The results show that the peak shear strength， cohesion and internal friction angle between the contact surfaces show the same law with the change of lining surface roughness， and the more rough the lining surface is， the three indexes will increase. The orthogonal analysis reveals that the most significant factor affecting the peak shear strength between the contact surfaces is the roughness of the lining， followed by environmental temperature and moisture content， and the effect of freezing time is not obvious. At the same time， the peak shear strength under low temperature， low moisture content， long freezing time and high roughness of the lining is larger. This result can provide theoretical support for the frost heaving hazard prevention of canal system engineering in seasonal frozen region.