Load-bearing performance of model GRS bridge abutments with different facing and reinforcement spacing configurations

Abstract

The paper reports the construction and surcharge load-testing of three (3) large-scale (~2.50 m-tall) GRS bridge abutment models in an outdoor test station to investigate the influences that the facing type and reinforcement spacing could have on their load-bearing performance. The facing types examined included cored Concrete Masonry Units (CMU) in Model #1 and much larger solid concrete blocks in Models #2 and #3. Reinforcement spacing in the first two models was 0.20 m, whereas it was increased to 0.30 m in the third model. Results show that using large facing blocks in GRS abutments could lead to significant improvements in their load-deformation performance relative to those with the CMU facing alternative. This improvement was observed even in the case of model with increased reinforcement spacing. Therefore, use of larger facing blocks could also help reduce the cost of GRS abutments by reducing the need for tighter reinforcement.