Applied Mechanics and Materials Vols. 204-208

Abstract: Steel corrosion is the most important and direct factor of reinforced steel concrete bridge durability damage as well as one of the main forms of the concrete bridge durability destruction. This article gives a comprehensive discuss from the corrosion mechanism, influencing factors and consequences.

Abstract: Guangxi the Yulin Tieshan'gang Expressway Bridge Grouting roadbed practice, describes a chemical grouting of construction methods to prevent highway traffic bridgehead depression after jumping disease, cone penetration test by heavy cone momentum before and after grouting Deflection detection method for testing the effects of the project, validation of the technology for the new road bridge (culvert) abutment soil reinforcement pretreatment oil with good results, can significantly improve the bearing capacity of foundation.

Abstract: Yangjiawan grand bridge is located in Lanzhou section of the Yellow River. In order to study the change laws near the bridge site of flow direction, velocity distribution, water surface slope, backwater area, river bed topography change and the effect of flood control on Lanzhou city after the bridge-built when the river gets through the average discharge, 20-year discharge, and 100-year discharge before and after the bridge-built. Based on the similar principle of model, the river near the bridge site was simulated by the hydraulic model experiment of movable bed. The result of experiment showed that the design data adopted in bridge project of Yangjiawan grand bridge were reasonable and fulfilled the requirements of city flood control. It was also suggested to excavate and dredge river near the piers of 6# ~11# and strengthen embankment near the riverbank and protection of constructions after the bridge-built.

Abstract: For the bridge health monitoring it is very important to understand the information what factors lead to the bridge damage. Clearly know these factors and the correlation between them can improve the efficiency of the bridge operation. But, the informed researches of damage factors are based on the expert's opinion and not on a systematic method of as the basis. First around 30 candidate factors are Scientific selected in reinforced concrete bridge related database in this paper, then these factors are divided into four common type, and in turn using rough clustering in the light of the four types, the rank of each type and comprehensive class are partition. Finally, the most significant influence factors to the structural damage are searched by the rough set theory (RST), and the association rules of each factor are analyzed.

Abstract: The cable-girder anchorage zone of cable-stayed bridge is vital to the safety of the entire structure. Aiming at uniformly conveying the vehicle and populaiton load as well as the load of the main girder to the cables, this zone shows unique characters with concentrated and massive loads, complex structures, comprehensive load paths and non-uniformly stress distributions. This paper established the 3D finite element modal for the Ronggui Cable-Stayed Bridge. A nonlinear analysis on its anchorage zone has been conducted to provide reasonable references for future design and optimization.

Abstract: Hong Kong-Zhuhai-Macao Bridge will cross Lingding navigation channel in the form of immersed tunnels, with two large artificial islands to provide change-over facilities between bridge and tunnel. In order to predict the effects on the hydrodynamic environment caused by the artificial islands, the physical model for the Bridge is built to analyze the changes of the tidal level and tidal current. The experimental results show that the drag force on flow is increased and the flow section area is decreased by the two large artificial islands built in the sea. Near both ends of the artificial islands, the velocities of tidal currents increase. The opposite side of the artificial islands, there is the recirculation zone with many vortexes in different scales, which have the periodic change from formation to disappearance. Affected by the topography, hydrodynamic conditions, as well as by the position, shape and scale of the artificial islands, the changes of hydrodynamic environment caused by both the west artificial island and the east one is similar in the change rules and different in the forms.

Abstract: The paper takes a non-conventional bridge as the case, analyzes the shortcoming of Plane Bar Structure Analysis Software (PBSAS) in non-conventional structure, in order to study load-carrying features of non-conventional type bridge, it proposes a new non-conventional type bridge analysis approach integrating both spatial analysis software and graphic software. Such an approach is to make an overall analysis firstly by large-scale general-purpose finite element software ANSYS, then to compute and recheck various control sections by professional software DR.BRIDGE. Thus to evaluate non-conventional type bridge, and the approach aims to provide a certain reference for analysis on similar bridges.

Abstract: This paper is aimed to verify the effects of reinforcement by tests before and after reinforcement of a two-way curved arch bridge with a clear span of 70m. Four 100kN and 180kN trucks are used for load tests of the bridge before and after reinforcement, and then the test values are compared with the calculated values. Tests before reinforcement has proved insufficient rigidity in some parts of the bridge, the design load grade is low, and the common fault in two-way curved arch bridges. The finite element numerical analysis tool ANSYS is used for finite element simulative analysis of the bridge, and the comparison of test values with calculated values shows the bridge can meet the existing design load grade after reinforcement. This paper has verified the feasibility and rationality of utilizing the physical unit of ANSYS for analysis of two-way curved arch bridges after reinforcement, and meanwhile, proved that the rigidity and design grade of bridges can be improved by reinforcement.

Abstract: According to the principle of minimum potential energy and energy differential methods and assuming the shear lag warp displacement function with consideration of prestressed steel, a set of differential equations are deduced with different boundary conditions in considering moment, torsion, shear lag coupling. And the numerical solution of the differential equations is gained by Galerlein method. In addition, explores the influence on shear lag with prestressed force or not, dead loading, live loading and prestressed forces of the prestessed steels the areas of them basing on the model experiment and finite element model. Comparisons of results for typical numerical examples are given to verify the accuracy and applicability of the present method.

Abstract: In order to accurately determine the weight of railway bridges parts, for railway concrete girder bridge case, this thesis is based on analysing the construction features of the railway concrete girder bridges and destructive characteristic of seismic damage and proposes a detailed method, which adopts combination of the analytic hierarchy process and the fuzzy synthetical evaluation. The weight of railway concrete girder bridges can be confirmed, by utilizing its logical and pairwise comparison method, Studies show that this is an effective method to confirm the weight of railway concrete girder bridges. It is of great value to quickly evaluate earthquake loss of railway bridges in the earthquake stricken areas.