60 A practical approach to the optimal design of precast, prestressed concrete highway bridge girder systems is presented. The approach aims at standardizing the optimal design of bridge systems, as opposed to standardizing girder sections. Structural system optimization is shown to be more relevant than conventional girder optimization for an arbitrarily chosen structural system. Bridge system...

16. Abstract Two prestressed high performance concrete (HPC) highway bridges were constructed in Texas utilizing concrete with 56 day design strengths of up to 97 MPa (14,000 psi). The utilization of HPC allowed for longer spans and larger girder spacing than typically used in conventional prestressed concrete bridges. An extensive research program was conducted to monitor the shortand long-ter...

A bridge is a structure providing passage over an obstacle without closing the way beneath. The required passage may be for a road, a railway, pedestrians, a canal or a pipeline. Now a days, bridge deck section of Box shapes are used widely. Most of the bridges constructed are of Box girders. Method of post-tensioning in the construction of bridges is very common today. Most of the bridges are ...

Deflection control is the crucial procedure in construction control of cantilever prestressed concrete continuous girder bridge. This paper summarizes the advantages of Grey theory’s poor information processing and abilities of Neural Network’s self-learning and adaption, and the combinational algorithm of grey Neural Network is applied to the prestressed concrete bridge cantilever construction...

The recently developed smart strand offers the possibility of measuring the prestress force of the tendon from jacking and all along its service life. In the present study, a method estimating the force distribution in all the tendons of a prestressed concrete (PSC) girder installed with one smart strand is proposed. The force distribution in the prestressed tendons is formulated by the frictio...

In the precast structures, optimization of structural elements is of great interest mainly due to a more rationalized way that elements are produced. There are several elements of precast prestressed concrete that are objects of study in optimization processes, as the prestressed joist applied in buildings slabs. This article inquires into cost minimization of continuous and simply supported sl...

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 Reinforced Polymer (CFRP) sheets provides a low-cost solution by increasing the speed of construction and reducing traf...

Most of the previous researches conducted on shear lag of box girders were only concerned about simple types of structures, such as simply supported and cantilever beams. The structural systems concerned in these previous researches were considered as determined and unchangeable. In this paper, a finite element method considering shear lag and creep of concrete was presented to analyze the effe...

INTRODUCTION The lower ratio of dead load to live load than existing multi-girder bridges, wide girder spacing and simplified structural system of the twin-girder bridges can give rise to change of dynamic characteristics of the bridges. Wider girder spacing and changing of dynamic features will also effect on a vibration serviceability of the bridges. What is worse, according to running vehicl...