Document Type

Article

Department/Program

Virginia Institute of Marine Science

Publication Date

2022

Journal

Journal of Waterway, Port, Coastal, and Ocean Engineering

Volume

148

Issue

5

First Page

04022015

Abstract

Oysters are hypothesized to affect the shear strength of nearby surficial seafloor sediment as fragments of oyster shells (shell hash) are typically more angular relative to sand particles alone, among other differences. Resistance to shearing is well characterized by the friction angle, which is estimated in this study from vacuum triaxial laboratory and portable free-fall penetrometer field tests. Friction angles of sediment with shell hash were higher relative to those of sediment without shell hash (via hydrochloric acid treatment) on average by about 19% (36.0°–30.2°, respectively). Triaxial confining pressures ranged between 2.1 and 49.0 kPa to simulate subtidal and intertidal aquatic conditions. Regularity (average of particle roundness and sphericity) values of sediment samples with shell hash were found to be less than those of samples without by about 6% (0.66 and 0.70, respectively), which indicates the particle shapes of the former are, overall, more angular and less spherical. Further study and methodology improvements are needed to decrease the approximate 9° friction angle discrepancy estimated from field- and laboratory-based tests. Knowing oysters have the potential to increase sediment shearing resistance helps establish a pathway of how shellfish colonies may contribute to mitigating surficial erosion around coastal infrastructure.

DOI

doi: 10.1061/(ASCE)WW.1943-5460.0000716.

Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.

Included in

Sedimentology Commons

Share

COinS