A Study on the Design of the Top Flange of a Modular T-Girder Bridge Using the Limit State Design Method

Jongho Park,Sungnam Hong,Sun-Kyu Park,Hongmyung Lee,Jinwoong Choi

doi:10.3390/app6120381

Abstract

This study involved applying a design code change on a modular bridge design. The top flange of a modular T-girder bridge was examined by the Korean Highway Bridge Design Code Limit State Design (2015) and was compared with the Korean Highway Bridge Design Code (2010) in terms of the stability under the bending moment. In addition, the cross-sectional height and reinforcement amount were re-designed to obtain a safety factor similar to the original code. The reinforcement arrangement and development of the transverse joints were examined in the section considered. The result indicated that the application of the Korean Highway Bridge Design Code Limit State Design (2015) increased the bending moment safety factor and decreased the width of the transverse joints. The results of the re-design with respect to a safety factor similar to that in the Korean Highway Bridge Design Code (2010) indicated that it was possible to reduce the cross-sectional height and reinforcement amount. Furthermore, based on the obtained section, the results revealed that the width of the transverse joints could be reduced by changing the arrangement of lap splices from the straight bar to the loop.

Highlights

In recent years, a considerable number of bridges have required replacement, repair, and strengthening owing to their degradation in performance with aging induced by deterioration, accidents, and natural disasters [1]
A new optimal cross section was obtained by performing a study with a safety factor that was similar to the designed flange using an existing strength design method (2010)
The reinforcement arrangement and the development and splice length of the transverse joint were analyzed based on the obtained cross section

Summary

Introduction

A considerable number of bridges have required replacement, repair, and strengthening owing to their degradation in performance with aging induced by deterioration, accidents, and natural disasters [1]. Maintenance and replacement of an existing bridge or construction of a new bridge is a labor-intensive involving a series of on-site fabrication processes that require a long construction period. Many studies have been conducted on the prefabricated bridges that can cope with various demands such as the minimization of traffic congestion and environmental impacts, cost reduction, securing site safety, and the improvement of quality and constructability [2,3]. A precast modular bridge involves the application and implementation of a plug-in technique in which a bridge is constructed by combining prefabricated standard members. Accelerated construction is enabled in the case of a modular bridge, and uniform quality and economic feasibility improvements are expected through the minimization of cast-in-place construction based on the partial replacement of damaged members using precast members.

Methods

Results

Conclusion