Behavior Analysis of Approach Slabs of IPM Bridges according to Unsupported Length and Settlement

토압분리형 교량 접속슬래브의 비지지길이와 지반 침하에 따른 거동 해석

  • Park, Min-Cheol (Department of Civil Engineering, Kumoh National Institute of Technology)
  • 박민철 (금오공과대학교 토목공학과)
  • Received : 2018.02.26
  • Accepted : 2018.05.04
  • Published : 2018.05.31


The approach slab plays an important role in the driving comfort of the connection section on a bridge. On the other hand, the approach slab only calculates the section force of a simple beam, and does not analyze the behavior. In this study, the unsupported length and settlement of approach slabs of IPM Bridges were examined using structural analysis. First, the section force was calculated by designing a simple beam, according to the length of the approach slab. The structural analysis was conducted to examine the behavior of the unsupported length and settlement. As the result, the bending moment decreased when the unsupported length was increased, and the bending moment increased when the settlement was increased. In addition, the design section force was estimated to be larger than the force of structural analysis, and the design of the approach slab according to the design guideline showed no problem in stability. Nevertheless, the vertical displacement exceeded the maintenance criterion of a 1/200 curve when the settlement exceeded 10 mm regardless of the unsupported length. Therefore, excessive settlement occurs in the reinforced earth retaining wall supporting the approach slab, and the design bending moment may be exceeded. Therefore, strict management is required.


Supported by : 도로교통연구원


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