Grillage analogy is a popular method for analyzing various types of highway bridges in designudoffices. For load assessment of existing bridges in Australia, mainly beam line model and grillage analogyudare employed to evaluate the structural integrity of bridge components due to live loadings. With majorityudof existing bridge networks designed per superseded design vehicles, the necessity to utilize moreudrigorous analysis methods to assess the load effects of bridges is indispensable. In this paper, variousudvehicular loading cases on grillage model of a box girder bridge with its equivalent finite element modeludwere made. Based on the numerical analysis, it was observed that component-level load effects of twoudmodels have notable differences irrespective of vehicle speed, position and loading. However, whenudglobal-level load responses are compared, the discrepancy in outputs drops dramatically. Developedudmodelling ratios are practical and found to be applicable to any modelling techniques for assessment ofudvehicular loading both in global and component-response basis. Proposed flowchart suggested for heavyudload assessment incorporates detailed and simple modelling approaches aligned with experimental dataudwhich can be used for periodic and long term monitoring of bridges. It can enhance the properuddetermination of bridge condition states, as any conservative estimation of bridge capacity may result inudunnecessary load limitations.
展开▼
