The research and achievements made on seismic subsidence of loess,obtained over the past30 years,were reviewed.Seismic Subsidence of Loess(SSL)has been verified by microstructure characteristics,dynamic triaxial exper...The research and achievements made on seismic subsidence of loess,obtained over the past30 years,were reviewed.Seismic Subsidence of Loess(SSL)has been verified by microstructure characteristics,dynamic triaxial experiments,and in-situ explosion tests,and has become an important subject in the field of seismic loess engineering research.While,the research is still in the stage of theoretical study of saturated soil,and there are no representative cases of seismic subsidence of loess in historical earthquakes.It is difficult to express structure characteristics using microstructure morphology.While,soil mechanics are available methods for this.Seismic subsidence judgment is absolute in some certain value ranges for several parameters.Therefore,probabilistic judgment should be developed.The seismic subsidence ratio is estimated mostly by empirical formulas or semiempirical and semi-theoretical formulas,which are based on laboratory data.These formulas are not established on the basis of physical process and mechanics of seismic subsidence,and this leads to more variables,complicated computation,and poor practicability.To solve these problems,we need to distinguish the main factors and corresponding variables,to establish a mechanics model for seismic subsidence estimation,and to characterize its physio-mechanical process.The key of anti-seismic subsidence treatment is to reduce the seismic subsidence property of soils,and to lower the interaction between the soil body and underground structures.展开更多
In order to study the sliding characteristics when the cable is connected with the other rods in the transmission line structures,a linear sliding cable element based on updated Lagrangian formulation and a sliding ca...In order to study the sliding characteristics when the cable is connected with the other rods in the transmission line structures,a linear sliding cable element based on updated Lagrangian formulation and a sliding catenary element considering the out-of-plane stiffness coefficient are put forward.A two-span and a three-span cable structures are taken as examples to verify the sliding cable elements.By comparing the tensions of the two proposed cable elements with the existing research results,the error is less than 1%,which proves the correctness of the proposed elements.The sliding characteristics should be considered in the practical engineering because of the significant difference between the tensions of sliding cable elements and those of cable element without considering sliding.The out-of-plane stiffness coefficient and friction characteristics do not obviously affect the cable tensions.展开更多
基金sponsored by the Basic Research Foundation of Institute of Earthquake Science,China Earthquake Administration(No.2011IESLZ03)
文摘The research and achievements made on seismic subsidence of loess,obtained over the past30 years,were reviewed.Seismic Subsidence of Loess(SSL)has been verified by microstructure characteristics,dynamic triaxial experiments,and in-situ explosion tests,and has become an important subject in the field of seismic loess engineering research.While,the research is still in the stage of theoretical study of saturated soil,and there are no representative cases of seismic subsidence of loess in historical earthquakes.It is difficult to express structure characteristics using microstructure morphology.While,soil mechanics are available methods for this.Seismic subsidence judgment is absolute in some certain value ranges for several parameters.Therefore,probabilistic judgment should be developed.The seismic subsidence ratio is estimated mostly by empirical formulas or semiempirical and semi-theoretical formulas,which are based on laboratory data.These formulas are not established on the basis of physical process and mechanics of seismic subsidence,and this leads to more variables,complicated computation,and poor practicability.To solve these problems,we need to distinguish the main factors and corresponding variables,to establish a mechanics model for seismic subsidence estimation,and to characterize its physio-mechanical process.The key of anti-seismic subsidence treatment is to reduce the seismic subsidence property of soils,and to lower the interaction between the soil body and underground structures.
基金Project(51308193)supported by the National Natural Science Foundation of ChinaProject(SGKJ[2007]116)supported by the Science and Technology Program of State Grid Corporation of China
文摘In order to study the sliding characteristics when the cable is connected with the other rods in the transmission line structures,a linear sliding cable element based on updated Lagrangian formulation and a sliding catenary element considering the out-of-plane stiffness coefficient are put forward.A two-span and a three-span cable structures are taken as examples to verify the sliding cable elements.By comparing the tensions of the two proposed cable elements with the existing research results,the error is less than 1%,which proves the correctness of the proposed elements.The sliding characteristics should be considered in the practical engineering because of the significant difference between the tensions of sliding cable elements and those of cable element without considering sliding.The out-of-plane stiffness coefficient and friction characteristics do not obviously affect the cable tensions.
