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The model test is an effective means to verify the mechanical performance of the bridge structure and to ensure the structural safety. The accuracy of design and manufacture is the key of model test.For a arch ridge with curved beam and skewed arch, the model test based on the similarity theory is analysized in detail including selecting materials, designing the size of section and calculating the geometrical parameters and so on, and the simulation reults between model and prototype are evaluated.Meanwhile some key technologies and valuable matters for design of aerodynamic model are presented,which provides an important reference value for model design of bridge structures.

Studying the deformation and fracture properties of soft materials can not only provide insight into the physical mechanisms underlying their superior properties and functions but also benefit the design and fabrication of rubberlike materials. In this paper, an application of the experimental digital moire method to determine the damage zone around crack tip for rubberlike material is presented. The measurement principles and the basic procedures of the method are explained in detail. The in-plane defomation distributions of crack tip fields under Mode I fracture condition are measured. In addition, the deformation of crack tip fields in the damage zones is also analyzed using the sector division mode. Finally, an analysis of the damage zone is proposed to describe crack-tip fields in rubber-like materials with large deformation.

A new constitutive model which is modified from Gao’s constitutive model has been introduced to analyze the finite deformation of a circular membrane with an embedded rigid inclusion under uniform pressure. Based on the basic controlling equations, the constitutive parameters and the dimension of the rigid inclusion have been discussed to demonstrate the influences on the membrane stresses.

Following the modified Gurson model in meso-mechanics, the models with spherical holes are established by the assumption which the matrix meets the two-parameter elliptic yield condition. The macroscopic stress expression which contains micro structure parameters and the material equation of yield surface are given by the upper bound theorem of plastic limit analysis. The parameters of the matrix material and damage(porosity) which impact on macroscopic yield surface equation are discussed. These works provide theory foundations for material damage and design.