In-Plane Lateral Cyclic Behavior of Insulated Concrete Form Grid Walls

Abstract

The in-plane lateral behavior of insulated concrete form grid walls consisting of prefabricated stay-in-place form blocks made of recycled expanded polystyrene and evenly spaced horizontal and vertical reinforced concrete cores was experimentally investigated. Incrementally increasing reversed cyclic drifts were imposed on sets of full-scale walls of two different aspect ratios and on two different vertical loading conditions. The results of the 13 experiments indicated that a consistent wall failure mode stemmed from fracture of the individual vertical cores. Additional vertical load was found to increase the strength and effective stiffness of the walls, but the effect on drift capacity and ductility depended on the wall aspect ratio. The residual stiffness and energy dissipation severely degraded within cycles of 1% drift for all aspect geometries and loading conditions. The stay-in-place form blocks had a significant positive influence on the behavior despite the material’s relatively low strength.