Compaction-Induced Distress of a Long-Span Culvert Overpass Structure

Compaction of backfill produces soil stresses and earth pressures which are not amenable to analysis by conventional methods. These compaction-induced earth pressures can produce stresses and deformations in flexible buried culvert structures which may significantly affect the stability and performance of these structures. This paper presents the results of a study in which deformations of a long-span flexible metal culvert were measured during carefully monitored backfill operations. These field measurements were then compared with the results of finite element analyses in order to investigate (a) the influence of compaction effects on culvert stresses and deformations, and (b) the ability of recently developed finite element analysis procedures to accurately model these compaction effects. The structure being monitored suffered excessive and unacceptable deformations which were shown to be primarily the result of compaction effects; these were well modelled by the analyses performed.