Static Tests of Shallow-Buried Reinforced Concrete Arches

摘要

The determination of the loads on and behavior of shallow-buried arch structures is complicated by the geometry of the arch and by existence if soil structures arches interaction effects. A common approach to the analysis of buried is to idealize the structure as a lumped parameter single degree of freedom (SDOF) system. The parameters which must be assumed for input into the SDOF model include a loading function and a structural resistance deflection relationship. The applied load on a buried arch due to overpressure at the ground surface includes a radial and a tangential component. The radial component can be measured experimentally; however, there seems to be no available transducers to measure the tangential component or interface friction. Two 1/12-scale model reinforced concrete arches were tested statically in a sand backfill. The arches were semicircular with an inside radius of 1 foot 9 inches and a thickness of 2 inches. One arch was covered with two layers of 1/32-inch-thick Teflon at the soil-structure interface to significantly reduce the interface friction, and the loading and behavior of the two arches were compared. Pretest finite element calculations were conducted to estimate the arch behavior. Based on both the experimental data and posttest calculations, it appears that interface friction on a shallow buried arch has an effect on its behavior, at least for the case of static loads. The load path at sections in the arch with a lower friction coefficient at the interface tended more toward pure compression than it did in the other arch. Keywords: Air blast simulation; Concrete structures; Hardened installation. (SDW)