Fatigue Testing of Shear Reinforcement in Prestressed Concrete T-Beams of Bridges

Matthias Hillebrand,Josef Hegger

doi:10.3390/app10165560

Abstract

In the recent years, bridges, as an important part of the national and international infrastructure, had to comply with stricter requirements due to increased heavy load traffic. Many of these bridge structures built in the 1960s and 1970s often contain less web reinforcement than the modern required minimum web reinforcement. In this context, the shear resistance under cyclic loading is of special interest. For this reason, experimental tests were conducted on prestressed concrete beams with and without shear reinforcement at the Institute of Structural Concrete of RWTH Aachen University to investigate the shear fatigue strength. This paper describes the recent tests on ten Tshaped prestressed beams with web reinforcement. The specimens were able to resist more load cycles than predicted by the approaches implemented in the Eurocodes for bridges. Based on the test results, design models for shear under cyclic loading should be reviewed and improved, especially regarding the assessment of existing structures.

Highlights

Bridges are an important part of the national and international infrastructure
The verification of shear resistance under cyclic loading has been required for concrete bridges in Germany since 2003 by introducing the DIN Fachbericht 102 [12], which is based on Eurocode 2 [13]
This paper presents fatigue tests on 10 T-shaped single span beams with shear reinforcement to complement the previous findings on I-shaped beams (I-beams) with shear reinforcement to another cross-section

Summary

Introduction

Bridges are an important part of the national and international infrastructure. Due to higher traffic volume, especially concerning heavy load traffic, the requirements on bridge structures have increased significantly in recent years [1,2,3,4]. Numerous German bridges were designed and built in the 1960s and 1970s for lower load classes [5]. Many existing bridges exhibit a deficit in shear strength, applying the current standards (e.g., Eurocode 2 [6,7,8,9]) because of the lower required shear reinforcement of previous design rules [10,11]. The verification of shear resistance under cyclic loading has been required for concrete bridges in Germany since 2003 by introducing the DIN Fachbericht 102 [12], which is based on Eurocode 2 [13]. A guideline to assess the load bearing capacity of existing bridges [14,15]

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Discussion

Conclusion