Applied Mechanics and Materials Vols. 178-181

Abstract: The application of ABAQUS in thermal stress analysis of mass reinforced concrete, focusing on the temperature field, crack propagation, ABAQUS modeling, finite element analysis approaches of thermal stress, is reviewed first in this paper. Then, based on the observation of one cable-stayed bridge pylon, a finite element analysis of existing crack tips in temperature stress is done, and the simulation results are compared with the measured ones to verify the validity and accuracy of the finite element calculation.

Abstract: Increasing the section method is the commonest method in double-curved arch bridge reinforcement. In order to research on the force condition of main arch ring in double-curved arch bridge reinforcement, we use internal force superposition method and stress superposition method to deduce the stress distribution of arch ring, and make contrastive analysis on each construction stage in bridge reinforcement. Internal force superposition method is unsafe; the stress superposition meets the actual situation.

Abstract: Combining with the construction of Dazhangcun Grand Bridge of Datong-Xian passenger dedicated railway line, typical pile foundations’ axial load of steel bars and settlement of foundation was monitored and analyzed. At the same time, some meaningful conclusion which were reference and guiding significance for design and construction of the similar project in collapsed loess district were drawn.

Abstract: Based on DaZhangCun Grand Bridge across HejingYuncheng Highway’s specific conditions of DatongXian Passenger Dedicated Railway Line, construction method of group support and five segments pouring was designed. Support resistance during concrete placing and tension was analyzed by the software MIDAS/CIVIL and the mechanical behaviors of the bowl-scaffold support was identified while considering the gravity and construction load. Then targeted strengthening supports had been taken to ensure security.

Abstract: Bridge upper hinge or just a widened, because of uneven settlement in upper structure based generate additional internal forces. To analysis Foundation does not uniform settlement on upper structure by force of effect, using niumake numerical analysis method on structure for analysis, established has new, and old bridge transverse mosaic Hou of simplified calculation formula, and on effect additional internal force of main factors for has analysis research, and results indicates that, using niumake numerical method on structure for simulation calculation comparison reasonable, and can using calculation structure anti-is foundation settlement difference allowed value, under on relying on engineering for calculation analysis, calculation out foundation of allows settlement value, Ensure the overall performance of widened bridge.

Abstract: This paper bases on building grey prediction model with the stress sequence of continuous beam bridge construction control section, discusses the application of the model in the construction control of the continuous beam bridge. SCGM (1, 1) dynamic model is based on test results of control cross-sections of Nanhe Bridge have been established for prediction, on the background of the construction of Nanhe Bridge, in Jiangsu province. The example shows that the prediction precision and adaptability of the model can achieve the requirements of the engineering construction, and the feasibility and adaptability of the construction control for bridge by using this model is validated to forecast the stress value in the practical construction control for a PC continuous bridge.

Abstract: Based on the engineering background as which a box-girder bridge under construction in typical winter weather of Qinghai-Tibet plateau is chosen, a diffusion equation of temperature of the structure has been established, whose choices of initial and boundary conditions are discussed according to the field monitoring data and local weather information including solar radiation and air convection. Secondly, some tests of numerical simulation have been done by FEM software, and related parameters of the model are obtained. Finally, based on the determinate parameters, the temperature fields of another box-girder bridge are simulated, which agree with the measured data in the field. All these show that the investigation is not only providing basic parameters for temperature loading in the control of construction process of the bridge, but also providing significant reference for the design and construction of the same kind of bridges in typical winter weather of Qinghai-Tibet plateau.

Abstract: For an existed reinforced concrete rigid-frame arch bridge in reconstruction project, reinforcement effects of the bridge are studied and discussed while the original load grades are maintaining and it is based on dynamic load test including scheme, execution and FEM analysis in this paper. In our investigations, such characteristics as dynamic flexibility, impact coefficient, natural vibrations and dynamic responses are analyzed. All the investigations show that the bridge meets the original-designed-loading requirement, which behaves well in dynamic characteristics after being strengthened and whose stiffness also satisfies requirement.

Abstract: Based on the South-to-North Water Diversion Bridge (70m+120m+70m prestressed concrete composite box-girder bridge with corrugated steel webs), structural static analysis of the bridge’s superstructure was taken out by finite element method, which were checked with the existing regulatory requirements. The result indicates that the carrying capacity in the ultimate limit state meet the requirement of the standard, the vertical shear stress of corrugated steel web satisfies the standard limit and the thickness of corrugated steel web satisfies the request, but the safety factor is not high.

Abstract: Against the problem of the aerodynamic interference effects on aerostatic coefficients between parallel continuous rigid frame bridges with high-pier and long-span, the aerodynamic interference effects on aerostatic coefficients of main beam in the parallel long-span continuous rigid frame bridges were investigated in details by means of wind tunnel test. The space between the two main beams and wind attack angles were changed during the wind tunnel test to study the effects on aerodynamic interferences of aerostatic coefficients of main beam. The test got aerostatic coefficients of 10 conditions. The research results have shown that the aerodynamic interference effects on aerostatic coefficients of main beam in parallel bridges can not be ignored. The aerodynamic interference effects on parallel bridge main beam is shown mainly as follows: The drag coefficient of main beam downstream dropped and the drag coefficient of main beam upstream changed but not change significantly. There are also the aerodynamic interference effects of lateral force coefficient and torque coefficient between the main beams upstream and downstream. The effects upstream are smaller and the effects downstream are larger.