冻土与结构接触面冻结强度研究现状与展望

全面掌握冻土与结构接触面冻结强度研究进展,是进一步深入开展冻土与结构接触面冻结强度研究的前提。首先,从接触面冻结强度定义、接触面冻结强度剪切试验仪器研发、动静荷载作用下接触面冻结强度试验、接触面冻结强度数值模拟等多个角度系统归纳接触面冻结强度方面的最新研究成果。其次,通过对比不同接触面冻结强度剪切仪,指出现有试验仪器的不足,提出接触面冻结强度成因及破坏机理缺乏深入揭示的原因,讨论现有冻土与结构接触面单元模型、接触面冻结强度预测方法等方面存在的问题。最后,提出研发改进冻土接触面冻结强度试验仪器以更好模拟实际工况的展望,指出应当运用冻土微观结构研究手段深入揭示接触面冻结强度成因及破坏机理,建议结合试验和理论推导构建更为合理的冻土与结构接触面单元模型,阐述以多影响因素试验为基础探寻更为完善的接触面冻结强度预测方法。通过国内外研究现状、存在问题及其发展趋势分析,为冻土与结构接触面冻结强度研究以及冻土区地下工程设计和隧道工程人工冻结加固等方面提供参考和指导。

Adfreezing strength at the interface between frozen soil and structure:research status and prospect

In order to comprehensively study the progress of adfreezing strength at the interface between frozen soil and structure, firstly, the latest research results about the adfreezing strength were systematically summarized from multiple angles, such as definition of adfreezing strength, the research and development of shear instru-ments used to test the adfreezing strength, the adfreezing strength test under static and dynamic loads, and the numerical simulation of adfreezing strength. Secondly, the shortcomings of the existing shear test instruments were pointed out by comparing different shear test devices. The reasons of the failure of in-depth revealing the causes and damage mechanisms of adfreezing strength were put forward. The existing questions with respect to the element model of interface between frozen soil and structure, the prediction method of adfreezing strength and so on, were discussed. Finally, it was proposed to research and develop the shear test instruments for better sim-ulating the actual working conditions. It was pointed out that the research methods in the microstructure of frozen soil should be used to reveal the cause and shear failure mechanisms of adfreezing strength. It was suggested to construct a more reasonable element model of interface between frozen soil and structure by combining experi-mental and theoretical deduction and to explore a more perfect prediction method of adfreezing strength based on the multi-influence factor test. Through the analysis of domestic and international research status, existing prob-lems and their development trends related to adfreezing strength, this study will be useful for experimental studies on adfreezing strength, designs and constructions of underground engineering in permafrost regions and artificial freezing reinforcements when tunneling.