Cumulative damage theory for composite materials: Residual life and residual strength methods

1985 ◽  
Vol 23 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Z. Hashin
2014 ◽  
Vol 1055 ◽  
pp. 161-164
Author(s):  
Tao Wang ◽  
Wei Zhong Zhang ◽  
Chen Xie ◽  
Deng Xia Zhang ◽  
Yan Ru

With the study subject of the gear transmission in an unmanned system, several common methods of fatigue life prediction are analyzed. According to the actual running state, S-N nominal stress method is used to predict the fatigue life of the gears. Based on the S-N data of the gear material and the linear cumulative damage theory, ANSYS is used to estimate the bending fatigue life of the gears, so as to obtain the fatigue life loss coefficient of the gears. It provides a reliable data reference of the design, use and maintenance of the gear transmission in unmanned system.


Author(s):  
Tingyao Wu ◽  
Zhou Chuanbo ◽  
Jiang Nan ◽  
Xia Yuqing ◽  
Bin Zhu

As for the slope with fault fracture zone, the fault fracture zone is the main sliding surface, whose shear strength parameter is the main calculation parameter of landslide occurrence. In this paper, shaking table model tests and damage theory were used to study the change of shear strength and mechanical cumulative damage model of fault fracture zone under the blasting vibration cyclic load. At first, the slope of Daye Iron Mine is selected as a case to study the shear strength weakening law of fault fracture zone by the similarity theory and the principle of the orthogonal test, in which the influence of the characteristics of vibration loading on the shear strength parameters of fault fracture zone with different thicknesses was studied. Secondly, by the assumption of Lemaitre strain equivalence and according to the extreme value characteristics of the normal stress-shear stress curve, the damage theory model of the fault fracture zone was reconstructed, and the microelement of fault was selected for analysis and divided into two parts, including damaged and undamaged materials. Finally, the results of the shaking table model tests were compared with the results of the shear cumulative damage model to verify the rationality of the theoretical model. Moreover, the predicted results of the theoretical model can better reflect the degradation trend of the fault fracture zone with the loading amplitude, normal stress, and loading times. It can be used as a reference for slope stability prediction under the action of cumulative static and dynamic loads.


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