Creep characterization of a fiber reinforced plastic material

Creep behavior of [±45°]_s composite material is characterized by using uniaxial creep and recovery tests. The well-known Schapery nonlinear viscoelastic consti tutive relation was modified to make it suitable for characterizing the creep behavior of this material. Then, using this modified Schapery constitutive equation, by which the vis coplastic and creep damage can be taken into consideration, the creep behavior of [±45°]. glass fiber reinforced epoxy laminate was studied. The constitutive parameters of the material were determined experimentally, and the procedure and method of determination of the material parameters are proved to be valid.

Influence of secondary void damage in the matrix material around voids

The mechanism of ductile damage caused by secondary void damage in the matrix around primary voids is studied by large strain, finite element analysis. A cylinder embedding an initially spherical void, a plane stress cell with a circular void and plane strain cell with a cylindrical or a flat void are analysed under different loading conditions. Secondary voids of smaller scale size nucleate in the strain hardening matrix, according to the requirements of some stress/strain criteria. Their growth and coalescence, handled by the empty element technique, demonstrate distinct mechanisms of damage as circumstances change. The macroscopic stress-strain curves are decomposed and illustrated in the form of the deviatoric and the volumetric parts. Concerning the stress response and the void growth prediction, comparisons are made between the present numerical results and those of previous authors. It is shown that loading condition, void growth history and void shape effect incorporated with the interaction between two generations of voids should be accounted for besides the void volume fraction.

Edital nº 01/86 : concurso público para Técnico em Material e Patrimônio

Torna pública a abertura de inscrição para concurso público destinado ao preenchimento de cargos de Técnico em Material e Patrimônio, do Grupo-Atividades de Apoio Legislativo da Câmara dos Deputados.

The effect of strain softening in the matrix material during void growth

Furthermore, the compressed flow driven by the piston is discussed. The consistent solution of gasdynamical equations including solar gravity is obtained for the unsteady and two-dimensional configuration, which is applied to the region between the piston and shock wave. This solution may satisfy the jump conditions of shock wave, which separates the region of compressed flow and quiet corona.

Visual Basic在油藏数值模拟中的应用

随着油藏数值模拟技术的发展以及油藏数值模拟软件的不断改进和完善,油藏数值模拟软件在油田开发中的应用越来越广泛。对油藏数值模拟软件计算出的数据进行整理不仅枯燥而且花费了大量时间。本文利用Visual Basic语言编制了处理ECLIPSE软件生成的油气田开发指标数据软件(RSMAN)。该软件方便了油气田开发指标的整理和汇总,软件界面友好,操作简单。

Lo visual como construcción. Desarrollo de un modelo pictórico de representación de la imagen

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