In order to deeply explore the energy characteristics of frozen calcareous clay and the degree of its in-fluence under the conditions of true triaxial stress path and multi-factor interaction,this study carries out the re-search of true triaxial compression test of frozen calcareous clay with the help of ZSZ-2000 true triaxial perma-frost test platform by adopting the design method of orthogonal test. The results show that the input energy of frozen calcareous clay is relatively low and the growth rate is slow in the initial compaction and linear elasticity stages;as the loading process progresses,the input energy gradually increases and so does the growth rate;At the damage stage,the input energy-equivalent stress curve shows an obvious jumping feature,and the sharp in-crease in input energy at this time indicates that the change in slope of the input energy curve is a microscopic manifestation of the unsteady development of cracks within the frozen calcareous clay. At the same time,the sudden sharp rise of the input energy curve also indicates the occurrence of instability damage. The damage curve characteristics of frozen clay are consistent with the characterization of the input energy curve,and it is rea-sonable to use the input energy to characterize the strength of frozen soil samples. Further analysis of extreme variance and hierarchical AHP analysis leads to a consistent order of superiority of the input energy influences:water content ω,mean principal stress coefficient b,temperature T,salinity φ,and circumferential pressure σ3. The moisture content has a significant negative effect on the input energy,the temperature and the mean princi-pal stress coefficient (MPSC) b have a significant positive effect on the input energy,and as the value of MPSC b increases,its effect on the input energy of the frozen specimens tends to decrease,and there is an optimum MPSC b=0.33 to maximize the increase in the input energy of the specimens. It is proposed to use the damage input energy to characterize the strength of permafrost,which provides an intuitive and comprehensive measure of the damage characteristics of permafrost by quantifying the total amount of energy absorbed by permafrost be-fore reaching the damage state. By analyzing the damage input energy,the energy absorption and dissipation mechanism of permafrost in the stress process can be better understood,which is of practical significance for guiding the construction of permafrost projects and promoting the development of theories and models of perma-frost mechanics.
维普
万方数据