The nature and causes of the differential settlement between a bridge deck and the adjoining highway pavement have been studied by only a few investigators. Highway engineers often attribute this fault in the riding surface to the settlement of the embankment because of the improper placement and compaction of material in the approach embankment. Although there exists suggestive evidence that this condition produces the bridge approach fault, no conclusive evidence has been presented which shows this to be the primary source of settlement. Jones (1), Bishop (2) and Deen (3) suggest that differential settlement between the bridge deck and approach pavement may be due in part to volume change of the embankment and in part to consolidation of the embankment foundation. According to Jones, the approach defect is often built in -- that is, the profile of the approach pavement does not fit smoothly with the profile of the bridge deck.

Report Date


Report Number

No. 273

Digital Object Identifier



The opinions, findings, and conclusions in this report are not necessarily those of the Department of Highways or the Bureau of Public Roads.