Soil-steel structures have been used widely as short-span bridges and as substitutes for concrete culverts. However, many of these structures have now shown signs of distress, with some suffering catastrophic collapse. Generally, such failures are related to the failure of the surrounding soil to provide the necessary support to the steel structure. In this paper, the concept of reinforcing the surrounding granular soil, as well as tying the flexible steel structure into the stable part of the surrounding soil by horizontally placed galvanized ties, is introduced. It is shown that this novel design concept would lead to improvements in the structural response during construction and at the service load stage. Such construction will (a) add considerable stiffness to the soil and decrease the movement of the backfill in service, such as during freeze-thaw cycles; (b) restrain the movement of the steel structure; and (c) induce large deformations, in case of overload, and therefore give ample warning before failure. Results from tests on soil-steel structural models are reported. This paper appears in transportation research record no. 1231, Analysis, design, and behavior of underground culverts.
Abstract