Behavior of Concave Segmental Soil Retaining Wall Using Porcupine Blocks

Motivated by recent studies showing concave slopes are more stable than planar slopes, this paper presents a feasible approach to build a dry-stone concave gravity segmental soil retaining wall (GSW) using special prefabricated concrete blocks (Porcupine Blocks). Unlike common segmental blocks that can only be assembled in one particular facing configuration, the Porcupine Block can be assembled with three different options, making it possible to build a concave GSW using a mixed block assembly. In this study, results from both centrifuge tests and numerical analyses indicated that a concave GSW has better performance than planar walls because concave facing contributes to reduced active earth pressure acting at the back of the GSW and the presence of porcupine offsets behind the concave wall provides additional downward forces to resist overturning. An additional highlight of this study is the use of 3D printing technique to fabricate 1:10 Porcupine Blocks for centrifuge model testing and to fabricate equipment parts for measuring the interfacial strength of the blocks.