Various innovative materials have been identified which may be suitable for use as stress absorbing layers behind integral bridge abutments to relieve any high lateral stresses which would otherwise build-up because of thermal expansion of the deck. A product from each of the generic types of material was selected for testing. The testing was aimed both at assessing the potential fitness for purpose of the type of material and also refining the test procedures which have been proposed for assessing their suitability for use as stress absorbing layers. The proposed tests included the determination of the modulus at the strain levels expected in service, the shear strength, and any permanent compression set locked-in after release of loading. Trials were undertaken to evaluate the effect of compacting free draining granular fill against some of the materials. (Author/publisher)
Abstract