Natural Hazards Research Summit 2022: GreenWall Systems: less steel, more earth for equitable and sustainable hazard resilience

This poster discusses a novel type of coastal defense, termed a 'GreenWall'. The proposed research on GreenWalls is inspired by the Doctoral work of the PI on Dual Row Retaining Walls. There is a clear need to re-examine the design philosophy of conventional coastal defenses and breakwaters following the failures caused by multi-hazard events in recent decades (e.g., following the 2011 Tohoku earthquake and tsunami event).
Previous studies have highlighted that systems that combine soil and structural systems to intentionally utilize the shear strength of the soil can be both resilient to multiple hazards and sustainable in terms of material use and environmental footprints. Results from centrifuge tests and numerical analyses for systems in dry sand inform the fundamental dynamic response of these systems and could inspire a move away from ultimately ambiguous dynamic earth pressure coefficients that have traditionally been used in academia and practice. The same systems founded in liquefiable soils showed a surprising resilience to catastrophic collapse, justified with a ratcheting mechanism that induces co-seismic relative suctions and shear dilation.
These findings are currently being progressed in the context of testing GreenWall designs using experimental and analytical studies at the Center for Infrastructure, Energy and Space Testing at the University of Colorado Boulder. Open issues, including the convergence of the historically different computational methodologies, experimental methods and especially scaling laws in coastal and geotechnical engineering are explored.