Bending Moment Multiplication Factor for AASHTO Live Loads Adopted in Jordan for Four Equal Spans with One Lane

Abstract

The main objective of this study is to determine a fixed multiplication factor for AASHTO LRFD that will be recommended to give the same result of bending moments due to 1.8 AASHTO LFD for four equal continuous spans with various span lengths of 20, 25, 30, 35 and 40 m.
The bridge models will be analyzed using the CSiBridge software. This study contains twenty finite element bridge models with one lane. Models are subjected to AASHTO LFD and AASHTO LRFD loadings to obtain the girders moments.
For one-lane models, bending moments, values -at exterior and interior girder - increase when the span length increases. Whereas, bending moment values for AASHTO LFD are higher than those for AASHTO LRFD. The maximum multiplication factors for one lane were obtained when span length equals to 20 m at second interior girder, such that bending moment factor is 1.35.
In case of live loads, the maximum factor for one lane are obtained in span length of 20 m at second interior girder, where the bending moment factor is 1.70