Based on the first order shear deformation theory and classic buckling theory, the paper investigates the creep buckling behavior of viscoelastic laminated plates and laminated circular cylindrical shells. The analysi...Based on the first order shear deformation theory and classic buckling theory, the paper investigates the creep buckling behavior of viscoelastic laminated plates and laminated circular cylindrical shells. The analysis and elaboration of both instantaneous elastic critic load and durable critic load are emphasized. The buckling load in phase domain is obtained from governing equations by applying Laplace transform, and the instantaneous elastic critic load and durable critic load are determined according to the extreme value theorem for inverse Laplace transform. It is shown that viscoelastic approach and quasi-elastic approach yield identical solutions for these two types of critic load respectively. A transverse disturbance model is developed to give the same mechanics significance of durable critic load as that of elastic critic load. Two types of critic loads of boron/epoxy composite laminated plates and circular cylindrical shells are discussed in detail individually, and the influencing factors to induce creep buckling are revealed by examining the viscoelasticity incorporated in transverse shear deformation and in-plane flexibility.展开更多
A creep buckling analysis of orthotropic viscoelastic thin plates,simply-supported all around, is given. In order to simulate the real condi-tions, the relaxation time of modulus in different pripeipal material orient...A creep buckling analysis of orthotropic viscoelastic thin plates,simply-supported all around, is given. In order to simulate the real condi-tions, the relaxation time of modulus in different pripeipal material orienta-tions is arbitrary in the constitutive equations of the plates. In deriving the as-sociated governing equations, transverse shear deformations are incorporated-By means of theoretical analysis, the instantaneous critical load and durablecriticaI load are obtained. In the example, a time incremental method is usedfor the first time to calculate the creep deformation of the viscoelastic plateswith initial imperfection, subjected to a constant compressive load for a longtime.展开更多
基金the Natural Science Foundation of Hunan Province (Grant No. 05JJ3008)the National Natural Science Foundation of China (Grant No. 10572049)
文摘Based on the first order shear deformation theory and classic buckling theory, the paper investigates the creep buckling behavior of viscoelastic laminated plates and laminated circular cylindrical shells. The analysis and elaboration of both instantaneous elastic critic load and durable critic load are emphasized. The buckling load in phase domain is obtained from governing equations by applying Laplace transform, and the instantaneous elastic critic load and durable critic load are determined according to the extreme value theorem for inverse Laplace transform. It is shown that viscoelastic approach and quasi-elastic approach yield identical solutions for these two types of critic load respectively. A transverse disturbance model is developed to give the same mechanics significance of durable critic load as that of elastic critic load. Two types of critic loads of boron/epoxy composite laminated plates and circular cylindrical shells are discussed in detail individually, and the influencing factors to induce creep buckling are revealed by examining the viscoelasticity incorporated in transverse shear deformation and in-plane flexibility.
文摘A creep buckling analysis of orthotropic viscoelastic thin plates,simply-supported all around, is given. In order to simulate the real condi-tions, the relaxation time of modulus in different pripeipal material orienta-tions is arbitrary in the constitutive equations of the plates. In deriving the as-sociated governing equations, transverse shear deformations are incorporated-By means of theoretical analysis, the instantaneous critical load and durablecriticaI load are obtained. In the example, a time incremental method is usedfor the first time to calculate the creep deformation of the viscoelastic plateswith initial imperfection, subjected to a constant compressive load for a longtime.
