FEM Analysis output for negative live load are significantly different than the values in the Line Girder analysis. CSibridge FEM model produces values closer to the liner girder analysis.

Hello.

I am using LEAP bridge steel to compare results from a CSiBridge refined model. The model is a 2 span bridge with fixed supports at the ends to obtain the max negative live load at the abutments.

All the moments and shears have correlated pretty closely except for the negative live load. Upon further discovery, LEAP bridge steel also has significant differences between the line girder and FEM model. I understand they will vary but should they be varying by 1500+-.  The CSibridge output is closer to the line girder analysis, which made me question if LEAP bridge steel FEM replicated the fixed condition accurately.

Please see screenshots below: