To accurately obtain the performance of concrete structures in coastal regions, it is necessary to correctly understand the damage evolution law of reinforced concrete (RC) members under real working conditions. In this paper, four RC beams, subjected to different levels of corrosion and sustained load, are first tested. Reinforcement corrosion coupled with sustained load increases the number and width of cracks at the soffit of beams but decreases their loading capacities. Crack width of the corroded beam under 50% of designed load is two times of that under 30% of designed load. Residual loading capacities of the corroded beams subjected to 30% and 50% of designed load are 87.5% and 81.8% of the control beam. A finite element model is developed for the corroded RC beams. Due to less confinement, concrete below and at the sides of reinforcements is subjected to a higher stress, compared to concrete above the reinforcements. Corrosion expansion of reinforcements is successfully modelled by a temperature-filed method, as it properly simulates the damage evolution of the corroded RC beams. As a result, concrete cracking, caused by the reinforcement corrosion, is well captured. Coupling reinforcement corrosion with sustained load significantly increases the damage level in RC beams, particularly for those subjected to a high sustained load. The whole damage evolution process of concrete cracking due to corrosion expansion under the coupling effect of sustained loading and environment can be simulated, thus providing a reference for the durability evaluation, life prediction, and numerical simulation of concrete structure.

This paper presents a strain-based damage model to predict the stress-strain relationship and investigate the damage onset and evolution of the fibre and matrix of a fully bio-resorbable phosphate glass fibre reinforced composite under three-point bending. The flexural properties of the composite are crucial, particularly when it is employed as implant for long bone fracture. In the model, the 3D case of the strain and stress was used and the response of the undamaged material was assumed to be linearly elastic. The onset of damage was indicated by two damage variables for the fibre and matrix, respectively. The damage evolution law was based on the damage variable and the facture energy of the fibre and matrix, individually. A finite element (FE) model was created to implement the constitutive model and conduct numerical tests. An auto-adaptive algorithm is integrated in the FE model to improve the convergence. The FE model was capable of predicting the flexural modulus with around 3% relative error, and the flexural strength within 2% relative error in comparison with the experimental data. The numerical indices showed that the top surface of the sample was the most vulnerable under three-point bending. It was also found that the damage initiated in the fibre, was the primary driver for composite failure under three-point bending.

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Through impregnation with UF and PF resin, the modification technology of Poplar was experimented and studied. The study results showed that WPG(weight percent gain) of the test-pieces impregnated with UF and PF resin had less difference. The wood vessels were scarcely filled by resin especially UF resin. Regardless of impregnating with UF or PF resin, the cell lumens near the veneer junctions are basically filled by the resin. But the most of the cell lumens depart farther from the veneer junctions were only filled by PF resin instead of UF resin.

This paper presents an investigation on the structural performance of steel plate shear wall (SPSW) with flush end-plate beam-column connections and infill precast reinforced concrete (precast RC) panels. Two single-span two-story SPSW specimens, including unstiffened SPSW (NBRP) and precast RC panel restrained SPSW (Con-BRP), are first tested, followed with a parametric study by finite element method. Precast RC cover panels are installed on both sides of the infill steel plate and are disconnected from steel frame. Test results indicate that the use of precast RC cover panels increases the load carrying and energy dissipation capacities of the SPSW structure, but decreases its ductility. It is also effective in reducing the inward flexural deformation of columns. Moreover, the stiffening effect of the infill steel plate on the beam-column connections remains, which is a result of the precast RC cover panel's resistance to the local buckling and the tears of the infill steel plates. The influence of the gap size between the precast RC cover plate and frame members on the failure mode of the specimen Con-BRP is also investigated, based on which a maximum gap size is recommended. Conclusions are drawn that SPSW structure with flush end-plate beam-column connections and precast RC cover panels fully exploits the strength of infill steel plates and exhibits excellent structural performance.