| Commonly the failure criterion of rock and soil materials includes energy failure criterion,but the curve usually used is the stress-strain curve when analyzing the shear failure process of rock and soil.At present,some scholars have begun to analyze the shear failure process of rock from the energy point of view.However,for the soil,the research based on energy angle is mainly focused on the direction of constitutive model.The energy change law of soil shear failure process is relatively small by triaxial compression test.In this paper,consolidated drained triaxial compression tests were carried out on saturated remodeled muddy soil and saturated Fujian standard sand.The axial-strain energy,radial-strain energy,absorbed energy,volume-strain energy,distortion-strain energy and related energy increment are calculated,and the change regulation of these energies in the shear process is analyzed.The main contents of this study are as follows:(1)According to the calculating methods of material mechanics,elastic-plastic mechanics and advanced soil mechanics,the formula of energy in unit volume sample and energy increment formula for unit axial strain or unit shear strain are obtained in triaxial test.(2)Saturated drainage remodeling triaxial test data of muddy soil were used to calculate each energy in soil samples.The change law of each energy of the soil sample is analyzed.The results show that there are three stages in the variation curve of each energy in saturated remolded mucky soil.At the stage of shear failure,the increment curve of absorption energy of soil sample is similar to that of clay"flow".In addition,the"dilatancy"phenomenon of the saturated remolded silt soil is explained from the energy point of view,and the energy needed for the"dilatancy"of the soil sample is derived from the distortion-strain energy.(3)According to the triaxial test data of saturated Fujian standard sand,the energy in the sand is calculated,and the change law of each energy of the sand sample is analyzed.The results show that the energy curves of sand show changes in the ch aracteristics of the three stages.When the saturated Fujian standard sand has the phenomenon of "dilatancy",The distortion-strain energy in the sand provides the energy for its "dilatancy".When the sand samples show the "strain-softening"phenomenon,the increment of the absorption energy of the unit shear strain is unchanged,and the distortion-strain energy increment and the volume-strain energy increment are similar to the change characteristics of"strain softening"(4)The energy characteristics of two different soils with different physical and mechanical properties of saturated remolded mucky soil and saturated Fujian standard sand are compared and analyzed.The results show that axial-strain energy,radial-strain energy,absorbed energy,volume-strain energy,distortion-strain energy and energy increment of the two soils have some commonalities in the shear failure process.Meanwhile,saturated remolded mucky soil and saturated Fujian standard sand have their own characteristics. |
