Analysis Of The Moisture-heat Transfer Law And Numerical Simulation During Soft Rock Mass Freezing-thawing Process

The problems of multi-fields coupling about geotechnical engineering in the cold regions are always many scholars' study hotspot,especially under the progress of the development in the west of China.This thesis studies the law of moisture-heat transfer coupling of the soft rock mass during freezing-thawing process following the study route-the study of theory,the analysis of experiment and the numerical simulation of cases based on the domestic and foreign scholars's study in this field。 The thesis brings forward the Dual Porosity Saturated-unsaturated Thermal-hydraulic Coupling Model for pores and cracks coexit in the soft rock mass structure and the water content is also mostly in saturated-unsaturated situation.At the same time,some key parameters of the quantification of coupling strength are concluded here which provides a reference for the future coupling experiment. This thesis attempts to carry out the moisture-heat coupling experiment of soft rock mass kind material- the concrete mortar in the freezing-thawing condition and the results show:the gradient of temperature influences the distributing of moisture field greatly and is the main drive power of moisture transfer;the content of quartz mineral in soft rock mass is direct ratio to the redistributing time of temperature field and the ratio of pore is also direct ratio to the freezing time which proves the basic pores are the main storage space for fluid.At last,the thesis numerically simulates the temperatue and moisture fields coupling of the wall rock in the cold region tunnel through the software Femlab.The simulation arrives in the collusion:the moisture field influences the temperature field greatly and the frozen circle is thinner with its influence,as well the aggrandizement of seepage coefficient,which can provide the reference for the geotechnical engineering design.