The prestressed ducts of concrete continuous girder bridges are usually three-dimensionally distributed and long in length. control prestress loss during construction is very important. In order to ensure the effect tensioning, test analysis friction parameters particularly Based on tension process a beam bridge, initial stress, loading time channel bridge tested by field tests. Combined with m...

The numerical results from a finite element (FE) model often differ from the experimental results of real structures. FE model updating is often required to identify and correct the uncertain parameters of FE model and is usually posed as an optimisation problem. Setting up of an objective function, selecting updating parameters and using robust optimisation algorithm are three crucial steps in...

Taking a prestressed concrete box girder as the research object, aiming at problem that bridge durability is reduced due to appearance of temperature cracks in girder, this paper adopted different types heat insulation materials, and theoretically analyzed structural field under high difference low environment from aspects whether source was set inside which provides reference for technical app...

................................................................................................................................... xi Acknowledgements ................................................................................................................. xii Chapter 1 General Introduction ...................................................................................................

The objective of this research is to investigate the advantages of using large-diameter 0.7 inch prestressing strands in pretention applications. The advantages of large-diameter strands are mainly beneficial in the heavy construction applications. Bridges and tunnels are subjected to a higher daily traffic with an exponential increase in trucks ultimate weight, which raise the demand for highe...

In order to find the relationship between deflected pre-stressed tendons and diagonal cracks of webs and provide basis to design and construction of bridges, a characteristics section model of a long span pre-stressed concrete continuous box girder, which is now under construction in Chongqing is analyzed by using nonlinear finite element program Midas-FEA. A numerical simulation analysis to th...

This study aims to analyze the longitudinal seismic performance of a typical multi-span continuous girder bridge with seat-type abutments under earthquake excitation, especially accounting for different abutment behaviors. Three-dimensional finite element models bridges are built considering nonlinearity columns, bearings, abutment-backfill interactions, pile-soil and pounding at expansion join...

The use of heavier trucks demanded upgrading of a twenty-seven year old bridge in Winnipeg, Manitoba, Canada. Analysis of the precast prestressed concrete girders using the current AASHTO Code indicates a deficiency in the shear capacity. Shear strengthening using Carbon Fibre R_einforced Polymer (CFRP) sheets provides a low-cost solution by increasing the speed of construction and reducing tra...

In this paper, the authors used finite element method to investigate longitudinal and transverse shear lag effects effect of aspect ratio on double-chamber cantilever concrete box girder under uniform distributed load. The results show that root section is positive lag, mid-span negative lag. direction, changes appear in girder. at fixed end significantly affected by ratio, degree different par...

In this article, we present an optimization model which incorporates uncertainty induced by geometrical imperfections. Within the model, geometrical imperfections are represented by means of random fields. The induced uncertainties are then treated using the concept of a convex model. The resultant problem is then solved in a two-stage optimization procedure. An arched girder is used to demonst...