Applied Mechanics and Materials Vols. 477-478

Abstract: In order to guide the construction of immersed tube tunnel of Hongkong-Zhuhai-Macao bridge project, the model tests of immersed tunnel tube were done in static water. Movements in six degrees of freedom, including three translational movements (sway, surge and heave) and three rolling movements (roll, pitch and yaw), were conducted. Four groups of environment conditions with different water depths were compared, and the added water mass and damping of tunnel tube changed with water depth were obtained. There test results can offer references for reasonable predictions of motion response of tube tunnel, and provide service to construction of immersed tube tunnel of Hongkong-Zhuhai-Macao bridge project .

Abstract: By using the intrinsic character of the truss structure, a new direct damage identification method of the truss structure based on residual force vector is presented. The stiffness connectivity matrix is got by sensitivity analysis, and it can be used to expand the stiffness perturbation matrix of damage structure, then, a new residual force vector is got, it can be solved directly, so the stiffness perturbation of structure is got, by it, the damaged locations and the extents of the truss structure are identified. At last, a hyper static truss structure example is given, the identification result shows that, only needed the first-order mode of the damaged structure, the damage can be identified accurately.

Abstract: To study the influence of structure combination on performance of rigid pavement hot-mix asphalt (HMA) overlays, four Hot-mix asphalt overlays are prepared for the research at the base of long-term performance of experimental roads. The results indicate that the SMA +AC+SMA sandwich structure can effectively restrain reflective cracking and rut. In addition, the structure can reduce the thickness and cost of pavement.

Abstract: The performance of the interface between fiber reinforced polymer (FRP) and concrete is one of the key factors to affect the behaviors of RC beams strengthened with FRP plate. Under external loading, the relative slip occurring on the interface between FRP plate and concrete causes the redistribution of stress and then the bearing capacity of the member is reduced. This study analyzes the effect of the interfacial soft behavior on the interfacial shear stresses of RC beams strengthened with FRP plate under symmetry concentrated loading. The analytical model is established, and the differential equations of interfacial shear stresses of RC beams strengthened with FRP plate are established. The calculated formulas of interfacial shear stresses are deduced under symmetry concentrated loading.

Abstract: Due to the rear-face steel plate of the steel plate concrete wall (SC) is very effective in preventing the perforation and scabbing of concrete, in order to resist the impact of commercial aircraft crash, steel plate concrete structures are usually used in the design of external walls of nuclear power plants. In this paper, the simulation analysis of the impact test of 1/7.5 scaled aircraft model impacting the steel plated concrete panels is carried out by using finite element code ANSYS/LS-DYNA. The Winfrith material model (*MAT_84) in ANSYS/LS-DYNA is used to simulate the concrete. The damage profile of panels and residual velocity of aircraft engine comparisons between the simulations and tests are presented in this paper. The results indicate that the damage modes from the impact simulations are very good agreement with the experimental result. It is verified that not only the selection of the material parameters needed for the steel plated concrete wall and aircraft model but also the entire analysis method was appropriate and effective. This paper provided the effective methodology for simulation of the response of the steel plated concrete structure of nuclear power plant due to commercial aircraft crash impact.

Abstract: Frame shear wall structure as a high-rise building one of the most widely used structure form, has good seismic performance and high bearing capacity, the frame shear wall structure research focused on the study of shear wall quantity more, pay attention to consider shear wall quantity and the intrinsic relationships between shear wall lateral stiffness and to seek the optimal design of shear wall stiffness, ignores the position of the shear wall, on the whole architecture of the influence of lateral stiffness, and can go, is set the location of the shear wall is difficult to study, this article will focus on the research of location of shear wall structure seismic performance, provide reference for the future of this kind of structure design.

Abstract: Based on geometrically nonlinear FEM, combined with stochastic imperfection mode, the stochastic imperfection mode superposition method was proposed for domes. Using the method the least favorable distribution of imperfection can be found and the corresponding critical buckling load of the structure can be calculated. Moreover the process of the structure with the load increment can be tracked. Finally the example demonstrated effectiveness of the method in finding the least favorable distribution of imperfection and the critical buckling load.

Abstract: As the significant difference in wind tunnel data between two scaled models of a practical engineering, the cause of this difference, which was regarded as blockage effect, was analyzed in this paper. Research shows that, for wind tunnel test with more surrounding buildings, blockage effect may result in serious data distortion, especially for lateral wind pressure, and existing correction method does not possess universality. Moreover, blockage ratio, as a global concept, is not appropriate to evaluate blockage effect of wind tunnel pressure data at different parts of building models. This study has reference value for blockage effect of wind tunnel pressure date in practical engineering.

Abstract: Structures with long span and high flexibility are very sensitive to the wind forces, so it is necessary to study on the wind effects on such structures. In this paper, based on section model wind tunnel high-frequency force balance tests, two horizontal base bending moments and shear forces of the typical supporting columns as well trestle bridge deck of the closed coal trestle under different wind directions were measured. The shape coefficients and their variations with the wind directions of the typical supporting columns as well trestle bridge deck were calculated then analyzed by the mean values of base forces. The experimental values of the shape coefficients were compared with those in the Chinese Load Code, the results shown that both were in good agreement, which verified the reliability of the test, which also illustrated that wind-resistant design of the coal trestle in accordance with the Code was reasonable. Based on analysis of the variances of base forces between overall model with and without surrounding buildings, influences of surroundings buildings were studied. Interference factors were proposed which provided the basis for the base forces checking and wind-resistant design of the long-span closed coal trestle structures.

Abstract: Reinforced concrete chimney lining initiation time should be slightly behind the outer wall. Adopting blasting scheme of preliminary demolition and big blasting cut is helpful to control the collapse of chimney and reduce the blasting vibration directions. Combined with a real blasting engineering, blasting demolition design of the reinforced concrete chimney under complex environmental condition was introduced.