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LRFD 설계를 위한 교대의 신뢰성 해석 모델

Reliability Analysis Modeling for LRFD Design of Bridge Abutments

  • 투고 : 2013.12.04
  • 심사 : 2014.08.25
  • 발행 : 2014.08.31

초록

본 연구의 목적은 신뢰성해석을 통해 교량의 하부구조인 교대에 대해 주요설계변수와 신뢰성계수의 관계를 정립하여 하중저항계수설계를 위한 신뢰성해석방법을 개발하는 것이다. 하중조건으로는 사하중, 연직토압 및 수평토압, 상재하중, 그리고 통행차량에 의한 활하중을 고려하였다. 고려한 하중에 대해 지반의 허용지지력, 전도, 활동 등을 반영하는 한계상태함수를 정의하여 신뢰성 해석을 몬테-카를로 시뮬레이션을 이용하여 수행하였다. 신뢰성 해석 결과 신뢰성지수에 가장 큰 영향을 미치는 인자는 내부마찰각이었으며 민감도해석 결과 신뢰성 지수는 저항계수와 수평토압의 변화에 따라 민감하게 변화하는 것을 알 수 있었다.

The objective of this paper is to develop a rational reliability analysis procedure for the LRFD design provisions of bridge substructures. A bridge abutments is considered in this study. The reliability analysis is applied to determine the relationship between the major design parameters for bridge abutment and reliability index. The considered load components include dead load, vertical and horizontal earth pressure, earth surcharge, and vehicle live load. Several limit states are considered: foundation bearing capacity, sliding, and overturning. The analysis results show that the most important parameter in the reliability analysis is the effective stress friction angle of the soil. The reliability indices are calculated using Monte Carlo simulations for a selected bridge abutment. The results of the sensitivity analysis indicate that reliability index is most sensitive with regard to resistance factor and horizontal earth pressure factor.

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참고문헌

  1. AASHTO (2013), LRFD Bridge Design Specifications. American Association of State Highway and Transportation Officials, Washington, D.C.
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