Showing papers by "Daniel W. Wilson published in 2020"

Vertical pullout tests of orchard trees for bio-inspired engineering of anchorage and foundation systems.

Abstract: Application of bio-inspired design in geotechnical engineering shows promise for improving the energy and material efficiency of several processes in infrastructure construction and site characterization. This project examines tree root systems for use in future bio-inspired design to improve the capacity of foundations used to support, for example, buildings and bridges. Foundation and anchorage elements used in industry are comprised almost solely of linear elements with a constant cross-sectional geometry. This functional form has remained the same for more than a century, primarily due to material availability and installation simplicity. Knowledge and understanding of the mechanisms that contribute to capacity development of natural nonlinear or branched foundation systems, such as tree root systems, could make foundation design more sustainable. The experiments described herein show that the root systems studied are 6-10 times as efficient as a conventional micropile system in developing tensile capacity on a per volume basis, with some systems displaying nearly 100 times efficiency in comparison to a conventional shallow footings. This paper explores the relationship between root system architecture and force-displacement behavior of tree root systems to better understand how to improve foundation capacity and demonstrates the potential for a more efficient use of materials and energy as compared to conventional pile and footing approaches.

NHERI Centrifuge Facility: Large-Scale Centrifuge Modeling in Geotechnical Research

Abstract: Author(s): Boulanger, RW; Wilson, DW; Kutter, BL; DeJong, JT; Bronner, CE | Abstract: The 9-m and 1-m radius geotechnical centrifuges at the Natural Hazards Engineering Research Infrastructure (NHERI) facility at the University of California at Davis provide the national research community with open access to unique and versatile modeling capabilities for advancing methods to predict and improve the performance of soil and soil-structure systems affected by earthquake, wave, wind, and storm surge loadings. Large-scale centrifuge models are particularly effective for the building of basic science knowledge, the validation of advanced computational models from the component to the holistic system level, and the validation of innovative soil remediation strategies. The capabilities and unique role of large-scale centrifuge modeling are illustrated using three example research projects from the shared-use NHERI facility. Education impacts stemming from operations activities and coordination of activities by the center’s user base are discussed. Future directions and opportunities for research using the NHERI facilities are discussed.