Abstract:
This presentation describes the field installation and load testing of prototype intermediate-scale root-inspired ground anchors. Plant root-inspired ground anchors and foundations endeavor to leverage the geometric principles of fibrous plant roots to reduce the construction time, cost, material consumption, and environmental impact of anchored earth retention and foundation systems. Previous publications describe the form and installation process of plant root-inspired ground anchors (RIGAs) (e.g. Mallett et al., 2021). In this study, a set of RIGAs were installed vertically at relatively shallow depth in coarse grained soil and vertical pullout load tests were performed to experimentally quantify the effects of anchor geometry and installation factors on the anchors’ expansion mechanism during installation and on ultimate anchor pullout capacity. Stresses in the expansive mechanism of the root-inspired ground anchor during installation and corresponding mechanism displacements were interpreted using analog displacement dial gages and analog recordings of pressure in the hydraulic equipment used for anchor expansion. Anchor displacement and loading during pullout load testing were measured and interpreted using the same measurement techniques. Anchors were exhumed after pullout load testing and their geometry characterized using 3-D laser-scan-generated models. This paper also discusses hypothesized correlations between anchor exterior geometry and installation factors with observed anchor behavior during both installation and pullout load testing.