This report presents the findings of the research performed on distribution of wheel loads on highway bridges under funding from thenational cooperative highway research program (nchrp). this study was performed in two phases; the first phase (nchrp 12-26) concentrating on beam and slab, and box girder bridges; and the second phase (nchrp 12-26/1) concentrating on slab, multi-box beam, and spread boxbeam bridges. for each bridge type three levels of analysis are considered. the most accurate level, level-three, involves detailed modeling of the bridge deck. level-two includes graphical methods, nomographs, influence surfaces; or simplified computer programs developed to apply such methods. level-one methods include simple formulae to predict lateral load distribution to various girders using a wheelload distribution factor. this research has resulted in a number ofmore accurate formulae for wheel load distribution, and recommendations for use of computer programs to achieve more accurate results. these recommendations focus on use of plane grid analysis as well asdetailed finite element analysis. also, as a result of this research, a draft specification is prepared for determination of wheel loaddistribution factors. this draft specification is recommended to replace the current aashto specification. this paper appears in transportation research record no. 1290, third bridge engineering conference, march 10-13, 1991, denver, colorado, volume 1.
Samenvatting