In order to investigate and research the fatigue cracking of prestressed concrete fatigue properties and loading and stiffness degeneration process,cyclic loading tests were carried out on six prestressed concrete bea...In order to investigate and research the fatigue cracking of prestressed concrete fatigue properties and loading and stiffness degeneration process,cyclic loading tests were carried out on six prestressed concrete beams and the stiffness degradation under fatigue was investigated. A simulation model of stiffness degradation is proposed based on the stiffness analysis of the fatigue-damaged section. The elastic modulus of damaged concrete and the effective residual area of steel were introduced as well as an adjusted three-stage concrete fatigue damage evolution model. The strip method was used to analyze concrete damage due to changing stress along the depth of the beam section. The simulation and test results were compared and a method of predicting fatigue deflection was presented based on the simulation model. The predicted results were compared with that of the neural network method. It is in good agreement for the simulation results with the test results. It is only less than5% error for the simulation model which can reveal the two-stage degradation of prestressed concrete beams under cyclic loading. It is more precise for the simulation prediction method under proper conditions.展开更多
In this paper,the degradation related parameters of GaInP/GaAs/Ge triple-junction solar cell induced by electron irradiation are carried out by numerical simulation.The degradation results of short-circuit current,ope...In this paper,the degradation related parameters of GaInP/GaAs/Ge triple-junction solar cell induced by electron irradiation are carried out by numerical simulation.The degradation results of short-circuit current,open-circuit voltage,maximum power have been investigated,and the degradation mechanism is analyzed.Combining the degradation results,the degradation of normalized parameters versus displacement damage dose is obtained.The results show that the degradation increases with the increase of the electron fluence and electron irradiation energy.The degradation normalized related parameters versus displacement damage dose can be characterized by a special curve that is not affected by the type of irradiated particles.By calculating the annual displacement damage dose and the on-orbit operation time of special space orbit,the degradation of normalized parameters can be obtained with the fitting curve in the simulation.The study will provide an approach to estimate the radiation damage of triple-junction solar cell induced by space particle irradiation.展开更多
基金Sponsored by the National Natural Science Foundation of China(Grant No.5117804251308159+4 种基金51578047)the National High Technology Research and Development Program Project(Grant No.2008AA11Z102)China Railway Corporation Research and Development of Science and Technology Plan Project(Grant No.2014G004-B)China Communications Construction Co.LTD Science and Technology Research and Development Projects(Grant No.2014-ZJKJ-03)
文摘In order to investigate and research the fatigue cracking of prestressed concrete fatigue properties and loading and stiffness degeneration process,cyclic loading tests were carried out on six prestressed concrete beams and the stiffness degradation under fatigue was investigated. A simulation model of stiffness degradation is proposed based on the stiffness analysis of the fatigue-damaged section. The elastic modulus of damaged concrete and the effective residual area of steel were introduced as well as an adjusted three-stage concrete fatigue damage evolution model. The strip method was used to analyze concrete damage due to changing stress along the depth of the beam section. The simulation and test results were compared and a method of predicting fatigue deflection was presented based on the simulation model. The predicted results were compared with that of the neural network method. It is in good agreement for the simulation results with the test results. It is only less than5% error for the simulation model which can reveal the two-stage degradation of prestressed concrete beams under cyclic loading. It is more precise for the simulation prediction method under proper conditions.
基金supported by the National Natural Science Foundation of China(Nos.11875223 and 11805155)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA15015000)+1 种基金the Innovation Foundation of Radiation Application(No.KFZC2018040201)the Foundation of State Key Laboratory of China(No.SKLIPR1803,1903Z)。
文摘In this paper,the degradation related parameters of GaInP/GaAs/Ge triple-junction solar cell induced by electron irradiation are carried out by numerical simulation.The degradation results of short-circuit current,open-circuit voltage,maximum power have been investigated,and the degradation mechanism is analyzed.Combining the degradation results,the degradation of normalized parameters versus displacement damage dose is obtained.The results show that the degradation increases with the increase of the electron fluence and electron irradiation energy.The degradation normalized related parameters versus displacement damage dose can be characterized by a special curve that is not affected by the type of irradiated particles.By calculating the annual displacement damage dose and the on-orbit operation time of special space orbit,the degradation of normalized parameters can be obtained with the fitting curve in the simulation.The study will provide an approach to estimate the radiation damage of triple-junction solar cell induced by space particle irradiation.