Applied Mechanics and Materials Vols. 587-589

Abstract: Larger displacement and inter-force response of the structure will be produced when self-anchored cable-stayed suspension bridge in longitudinal earthquake. For the isolation system of self-anchored cable-stayed suspension bridge, whose main tower is set the lead core rubber isolation bearing. This essay does the nonlinear time history analysis under the longitudinal earthquake about the isolation system when the viscous damper is put in different location. Analysis results show that inter-force and displacement of control section and control node are reduced greatly in hybrid vibration control. The result is obvious when the viscous damper is set both in the main tower, the side block and only in the main tower.

Abstract: Wood possesses material properties that may be significantly different from other materials normally encountered in structural design. It is necessary for the engineer to have a general understanding of the properties and characteristics that affect the strength and performance of wood in bridge applications. This paper discusses the mechanical properties of wood, including elastics properties and strength properties. Timber bridge are often exposed to harsh environment conditions. Over time, this exposure can lead to deterioration. In turn, this deterioration may lead to a loss of structural integrity that is detrimental to the structure and its users. Timber structural elements are susceptible to degradation due to environmental and loading conditions. A variety of inspection techniques can be employed to locate damage and decay in timber members in order to maintain structural performance. Methods of non-destructive techniques for timber bridges are getting more and more important. This paper presents several non-destructive methods to timber bridge structures.

Abstract: In order to improve the work on investment estimate of municipal bridge project,the paper screens the impact factor of municipal bridge project investment estimation to build municipal bridge project investment estimation model. It regards hollow plate girder bridge as the research object.It obtains the initial set of impact factor affecting municipal bridge project investment model by analyzing the relevant literature using the method of information precipitation.And it screens out 10 feasibility impact factor set by analyzing the data collected by the questionnaire with membership degree analysis.

Abstract: The cable-stayed bridge got rapid development in recent years. And for long-span cable-stayed bridges, the cable-girder anchorage structure is a key component in designing. The function of the cable-girder anchorage structure is to transfer the load between cables and the main girder. With the complex load transfer mechanism and stress concentration induced by large cable force, rational design of cable-girder anchorage structure is critical to long-span cable-stayed bridges. Take a certain long-span railway cable-stayed bridge in Zhejiang Province as the investigation, the load transfer mechanism and the stress distribution state was studied by finite element model. The research indicated that the design of this anchor box was rational. The stress distribution on each plate of the anchor box was relatively uniform. And the load transfer path and mechanisms of the main components of this anchor box were clear.

Abstract: The diagonal cracks in the web of box girder bridge which caused by excessive loss of vertical prestressed tensioning force are particularly common. In order to effectively detect the real force of the vertical prestressed rebars. Take the exposed section of the vertical prestressed rebar as an analysis entity, and take the rebar as a rigid body; the anchoring segment is simulated by an annular outrigger and an annular elastic support. When vertical pretress tension changes, the stiffness of elastic support and the vibration frequency also change accordingly, the change of the value of tensile force can be reflected by the vibration frequency. Combined with the model test data, the nonlinear elastic parameter model between the finish .deformed rebar vertical tensioning force T and the space elastic support stiffness K is established. The validity of the method was checked by extension test. The study indicate that this method is accurate, fast and convenient for engineering applications, can effectively improve the construction quality.

Abstract: Vehicle load is one of the most important factors to influence the structural security and applicability of the highway bridge. In this study, in order to learn the situation of the vehicle loads on expressway in recent years, and to provide the basic standard for highway bridge load, collected the dynamic data of nearly 4000 trucks through the traffic investigation of a section of 24 consecutive hours on the expressway in Hebei province. According to the actual survey results for statistical analysis and the principle of equivalent fatigue damage, the model of 5 kinds of daily operation vehicle load was deduced based on the measured data and the fatigue loading spectrum was established. The results of the survey can provide references for the design of the highway bridge fatigue load and fatigue assessment in our province in the future.

Abstract: The paper analyzed the temperature control technique measures of mass concrete in the pile cap of main pier in Yangtze River Bridge. Consider the effect of the cooling pipe, ANSYS finite element analytical software was used to calculate the temperature field of the pile cap in the construction, the distribution rules of the temperature field was simulated by finite element analysis. It is shown that the cooling effect of the mass concrete is obvious by using cooling water pipe, the finite element calculation results can be used to lead to the design and construction. It also provides the reference to develop a reasonable temperature control solutions during the construction of the similar mass concrete.

Abstract: The paper describes the basic principles of stress-free status control method and application in construction control of various phased construction bridge.Through a series of engineering example calculation and analysis shows that: the method can solve all kinds of problems in bridge construction control calculation directly and efficiently, its application and promotion can promote the whole bridge construction control level of progress.

Abstract: This paper presents the fatigue checking methodology of the steel bridge members according to Romanian norm SR 1911-98 and EN 1993-1-9. A comparative analysis regarding the fatigue checking of the main girders of a 30 m span steel railway bridge is made. The concluding remarks and observations are useful in the design activity of this type of structures.

Abstract: The finite element analysis method of variable cross-sectional Concrete-Filled Steel Tubular (CFST) laced columns is put forward. The influence of longitudinal elements slope and slenderness ratio on stability factor are analyzed, and the computational formula of slenderness ratio of variable cross-sectional CFST laced columns is presented. On the basis of the analytical results, a rational methodology for calculating the stability factor of four-element variable cross-sectional CFST laced columns is proposed.