With many major projects under construction,more and more attention is paid to rheological mechanical properties of rock mass,and extensive researches are carried out for rheological constitutive modeling of rock mass...With many major projects under construction,more and more attention is paid to rheological mechanical properties of rock mass,and extensive researches are carried out for rheological constitutive modeling of rock mass.Based on viscoplastic theory,a new rheological constitutive model is proposed.The rationality and validity of proposed model are verified through the creep test data.The results show that the rheological constitutive model based on viscoplastic theory is able to simulate the typical creep curves of rock mass and the identified parameters are reasonable.Therefore,the rheological constitutive model could be used to describe the rheological mechanical behaviour of rock mass.展开更多
Rheologic characteristics of soil are very important in soil mechanics. Almost every aspect of research on soil mechanics deals with rheologic characteristics of soil. Although more than half century has passed, study...Rheologic characteristics of soil are very important in soil mechanics. Almost every aspect of research on soil mechanics deals with rheologic characteristics of soil. Although more than half century has passed, study on rheologic characteristics of soil only made a very small progress, which was due to the two facts: (1 ) the complexity of rheologic characteristics of soil; (2) the research methods based on experimental fOrmulas. Based on thermodynamic theory and endo-chronic theory, a new intrinsic constitutive equation for rheologic characteristic of soil was developed, which combined with two groups of internal state variables and their correlative intrinsic time. The new intrinsic constitutive equation did very well in predict essential features of the rheologic behavior of soil, with which the dilatancy of soil during the rheologic process could be described.展开更多
The initiating condition for the accelerated creep of rocks has caused difficulty in analyzing the whole creep process.Moreover,the existing Nishihara model has evident shortcomings in describing the accelerated creep...The initiating condition for the accelerated creep of rocks has caused difficulty in analyzing the whole creep process.Moreover,the existing Nishihara model has evident shortcomings in describing the accelerated creep characteristics of the viscoplastic stage from the perspective of internal energy to analyze the mechanism of rock creep failure and determine the threshold of accelerated creep initiation.Based on the kinetic energy theorem,Perzyna viscoplastic theory,and the Nishihara model,a unified creep constitutive model that can describe the whole process of decaying creep,stable creep,and accelerated creep is established.Results reveal that the energy consumption and creep damage in the process of creep loading mainly come from the internal energy changes of geotechnical materials.The established creep model can not only describe the viscoelasticeplastic creep characteristics of rock,but also reflect the relationship between rock energy and creep deformation change.In addition,the research results provide a new method for determining the critical point of creep deformation and a new idea for studying the creep model and creep mechanical properties.展开更多
基金Sponsored by the Natural Science Foundation of Fujian Province(Grant No.2008J0171)
文摘With many major projects under construction,more and more attention is paid to rheological mechanical properties of rock mass,and extensive researches are carried out for rheological constitutive modeling of rock mass.Based on viscoplastic theory,a new rheological constitutive model is proposed.The rationality and validity of proposed model are verified through the creep test data.The results show that the rheological constitutive model based on viscoplastic theory is able to simulate the typical creep curves of rock mass and the identified parameters are reasonable.Therefore,the rheological constitutive model could be used to describe the rheological mechanical behaviour of rock mass.
文摘Rheologic characteristics of soil are very important in soil mechanics. Almost every aspect of research on soil mechanics deals with rheologic characteristics of soil. Although more than half century has passed, study on rheologic characteristics of soil only made a very small progress, which was due to the two facts: (1 ) the complexity of rheologic characteristics of soil; (2) the research methods based on experimental fOrmulas. Based on thermodynamic theory and endo-chronic theory, a new intrinsic constitutive equation for rheologic characteristic of soil was developed, which combined with two groups of internal state variables and their correlative intrinsic time. The new intrinsic constitutive equation did very well in predict essential features of the rheologic behavior of soil, with which the dilatancy of soil during the rheologic process could be described.
基金This work was supported by the National Natural Science Foundation of China(Grant No.41941018)the Science and Tech-nology Service Network Initiative of the Chinese Academy of Sci-ences(Grant No.KFJSTS-QYZD-174),and the Guangxi Natural Science Foundation(Grant No.2020GXNSFAA159125).
文摘The initiating condition for the accelerated creep of rocks has caused difficulty in analyzing the whole creep process.Moreover,the existing Nishihara model has evident shortcomings in describing the accelerated creep characteristics of the viscoplastic stage from the perspective of internal energy to analyze the mechanism of rock creep failure and determine the threshold of accelerated creep initiation.Based on the kinetic energy theorem,Perzyna viscoplastic theory,and the Nishihara model,a unified creep constitutive model that can describe the whole process of decaying creep,stable creep,and accelerated creep is established.Results reveal that the energy consumption and creep damage in the process of creep loading mainly come from the internal energy changes of geotechnical materials.The established creep model can not only describe the viscoelasticeplastic creep characteristics of rock,but also reflect the relationship between rock energy and creep deformation change.In addition,the research results provide a new method for determining the critical point of creep deformation and a new idea for studying the creep model and creep mechanical properties.