Development of Load Carrying Capacity Evaluation Model Based on Bridge Frequency Response

Roh, Hwasung; Ryu, Minkwan; Park, Kyung-Hoon

Journal of the Korean Society of Hazard Mitigation 2015;15(4):169-176.
Published online August 31, 2015.

주파수 응답에 기초한 교량 내하력 평가 모델 개발

노화성, 유민관, 박경훈

Development of Load Carrying Capacity Evaluation Model Based on Bridge Frequency Response

Hwasung Roh, Minkwan Ryu, Kyung-Hoon Park

Abstract

The current method evaluating a load carrying capacity of bridges requires numerical structural analysis model and vehicle passing test in field on the bridges. Here, the numerical model such as finite element model of the bridges needs to reflect their current health state each evaluation time. Also, the field test requires a traffic closing, which frequently leads to traffic jam. Furthermore, the peak impact factor should be decided considering all possible vehicle speeds on the bridges. However, such all vehicle speeds cannot be considered since the testing-truck driver cannot make these all vehicle speeds during the test. Therefore, in this study, a new model is proposed as an alternative to the current method, which is based on the frequency-peak impact factor response spectrum and requires the fundamental frequency of bridges. This paper explains in details the framework of the model, using a simply-supported beam bridge as an example.

Key Words: Load carrying capacity evaluation; Framework; Frequency-peak impact factor response spectrum; Response reduction factor

요지

기존의 교량 내하력 평가 방법은 매번 구조해석모델 구축과 재하시험을 실시해야 하며, 이때 구조해석모델은 평가 당시의 교량의 건강 상태를 대변하고 있어야 한다. 또한 현장시험의 경우 교통 통제로 인한 교통체증과 최대 충격계수가 도출되는 차량속도를 재현하기가 어렵다. 본 논문에서는 교량의 기본 주파수 또는 진동수만을 기반으로 주파수-최대 충격계수 응답스펙트럼을 이용하는 새로운 형태의 교량 내하력 평가모델을 제안하였으며, 단순교를 예제로 하여 이 모델의 프레임웍을 자세히 설명하였다.

핵심용어: 교량내하력 평가; 프레임웍; 주파수-최대 충격계수 응답스펙트럼; 응답감소계수