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In this thesis, an analytical tool for predicting fatigue performances of RC bridge slabs isdeveloped based on the concept of fracture mechanics. The degradation of bridging stress in thenormal direction of concrete cracks is considered as a primary mechanism for the propagation ofboth flexural cracks and shear cracks that induce the failure of RC slabs. The analysis of RC slabs...

Recent advances of interfacial micromechanics in fiber reinforced composites using micro-Raman spectroscopy are given. The faced mechanical problems for interface design in fibrous composites are elaborated from three optimization ways: material, interface, and computation. Some reasons are depicted that the interfacial evaluation methods are difficult to guarantee the integrity, repeatability,...

A variational asymptotic micromechanics model has been developed for predicting effective thermoelastic properties of composite materials, and recover the local fields within the unit cell. This theory adopts essential assumptions within the concept of micromechanics, achieves an excellent accuracy, and provides a unified treatment for 1D, 2D, and 3D unit cells. This theory is implemented using...

The ear detects sounds so faint that they produce only atomic-scale displacements in the mechanoelectrical transducer, yet thermal noise causes fluctuations larger by an order of magnitude. Explaining how hearing can operate when the magnitude of the noise greatly exceeds that of the signal requires an understanding both of the transducer's micromechanics and of the associated noise. Using micr...

A multiphysics micromechanics model is developed to predict the effective properties as well as the local fields of periodic smart materials responsive to fully coupled electric, magnetic, thermal and mechanical fields. This work is based on the framework of the variational asymptotic method for unit cell homogenization (VAMUCH), a recently developed micromechanics modeling scheme. To treat the...

a new model is proposed in this research to calculate the longitudinal strengthof unidirectional e-glass reinforced polymer composites exposed to sulfuricacid environment, using a micromechanics model. in the proposed method,it is assumed that the residual strength of the degraded composites under acidic environment can be calculated by knowing the degraded strength properties of the constituen...

The in-plane thermo-elastic behaviour of woven fabric reinforced composites is analysed using a combination of published micromechanics and finite element techniques. The repetitive unit of an arbitrary woven fabric composite is divided into elements of which the thermo-elastic properties are determined using micromechanics. The properties of the repetitive unit are obtained using the finite el...

A micromechanics based thermal model was developed to predict the temperature and degree of cure (DOC) distribution inside a unidirectional fiber reinforced composite during the curing process. Using the concentric cylinder assemblage (CCA) model as a representation of the composite microstructure, the effective thermodynamic properties of the composite were computed based on the fiber and matr...