Taking bridge structures in service period as research objects, durability experimental method of reinforced concrete (RC) components strengthened with fibre reinforced polymer (FRP) under time-varying hot-wet environment and random fatigue load coupling/interaction was discussed and corresponding experimental system of structural components was developed and integrated. To prove the effectiveness and feasibility of the experimental method proposed, durability/environmental fatigue experiments of RC beams strengthened with carbon fibre laminates (CFL) were carried out including the following four experiments: a) non-interaction experiments (the current method) of constant temperature, constant humidity and fatigue loads, b) interaction experiments of constant temperature and humidity and fatigue loads, c) interaction experiments of real service environment and fatigue loads, d) interaction experiments of real service environment and vehicle random loads. The results showed the durability/environmental fatigue experimental method proposed by this paper was effective and feasible.

Correlation coefficients of mode shape between higher frequency modes and lower frequency modes are given. Then 17 high modes were initially selected as the dominant high modes in the analysis of wind-induced response, and cumulative mode correlation was used to judge the rationality of the method of selecting dominant high modals, so dominant modals of wind-induced response analysis are constructed. Based on these, the wind-induced vibration response of spherical Kiewitt cable dome was analyzed in frequency domain using CQC method. Through analyses of computational results, it is found that the selecting method of dominant modals by using the mode correlation coefficient can be applied in frequency domain analysis for wind-induced vibration response of cable dome structures. If the first 100 modals are considered into the analysis, the computational results obtained will be high precision.

The static failure can be seen as a special fatigue failure, which means the static failure is the fatigue failure only bearing one cycle under the ultimate-strength loading. By learning from the analysis of fatigue damage, the stress- strain curve and damage of steel fiber reinforced concrete under uniaxial loading have been studied in this paper. The damage evolution equation can be derived from the damage theory, and it can be used to describe the relationship between the damage variable and strain. According to the strain equivalence principle, the corresponding constitutive equation considering damage can be obtained. Finally, comparisons among test results, the model and ansys simulation results show that the model is suitable to describe the uniaxial stress-strain curves of steel fiber reinforced concrete.

By using finite element method, analysis the static response of internal force and displacement of gravity dam under water and no-load factors. The change of the stiffness ratio and the difference of dam and foundation stiffness at the dam heel and toe are considered. The stress in the key parts of the dam and the maximal displacement on the dam top are obtained. It is found that the change of foundation stiffness affects the stress of the dam, and the displacement decreases with the increasing of the foundation stiffness. Some computational results and conclusions are the theoretical basis for the optimization design of the gravity dam.

The torsion of the multi-span aqueduct body was studied under the lateral seismic excitation by FSI computational analysis. The results show that the difference of stiffness of both sides has little influence on the torque of the aqueduct body. However, the influence of the torque on both end sections of the aqueduct body is not to be neglected. For the simply-supported beam aqueduct, if the centre moment of the aqueduct is adopted as the controlling condition to design the whole aqueduct body and when the bending-torsion effect is small, the safety of anti-seismic structures can meet the requirements. Otherwise, on the section between the centre section of the aqueduct body and the end slot section, the safety of anti-seismic structures could not meet the requirements.