This article describes various reasons that can lead to nonzero moment at abutment location of bridge objects.

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Nonzero moment due longitudinal restraint

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For results reported for individual girders, the moments reported on the "Bridge Object Response Display" form are obtained from section cuts that include both the girder and the tributary section of the deck. When there is a skew at the abutment, the skew also causes twisting of the deck and the interaction with the adjacent girder or the deck of the adjacent girder may cause negative section cut moment at the abutment. In other words, the reported moment is not solely caused by the vertical reaction at the support, but the contribution of all joints included in the section cut must be accounted for.

See also

• Effect of insertion point on beam reactions test problem