U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
|This report is an archived publication and may contain dated technical, contact, and link information|
Publication Number: FHWA-HRT-04-095
Date: November 2004
Manual for LS-DYNA Soil Material Model 147
PDF Version (1.96 MB)
PDF files can be viewed with the Acrobat® Reader®
APPENDIX A. DETERMINATION OF PLASTICITY GRADIENTS
In the following, the gradient of the yield surface in stress space is determined. The yield function is:
J3= third invariant of the stress deviator
e= material parameter describing the ratio of triaxial extension strength to triaxial compression strength
We need to find . A convenient method is:
Here, si is the stress deviator. Now, we just need to determine the coefficients C1, C2, and C3.
Note that is not defined at e = 0.5 and .
For the hardening functions, see equations 40 and 41.
In comparison with Abbo and Sloan:
Topics: research, safety, infrastructure, structures, materials, geotechnical
Keywords: research, safety, infrastructure, structure, materials, soil, LS-DYNA, shear, elastic, plastic, damage, roadside safety
TRT Terms: Soil mechanics–Mathematical models–Handbooks, manuals, etc, Shear strength of soils–Testing–Computer simulation–Handbooks, manuals, etc, Foundation soils, Roadside structures, Soil structure interaction, Finite element method, Impact loads, Computer models