Integrated computational-experimental soil behavior characterization from direct simple shear tests on Boston Blue Clay

A constitutive model that represents soil behavior under a wide range of loading conditions is necessary for the simulation of complex boundary value problems. However, most laboratory tests are interpreted with an assumption of uniform stresses and strains within the tested soil specimen even when the specimen is known to experience non-uniform stress-strain distribution as in the Direct Simple Shear (DSS) test. Numerous tests are often needed to fully characterize a soil’s nonlinear and anisotropic and time-dependent behavior and to develop an appropriate soil model. This study utilizes an evolutionary inverse analysis approach to directly extract non-uniform stresses and strains within an undrained DSS test specimen, and which is subsequently to K0 consolidated-undrained direct simple shear (CK0UDSS) tests on Boston Blue Clay (BBC). The extracted soil behavior is consistent with known behavior of BBC including anisotropic stress-strain response and small strain nonlinearity obtained under complex laboratory loading conditions. The developed material models from DSS tests on Boston Blue Clay (BBC) are directly applied to deep excavation case histories. The analysis results show that the global responses, such as lateral wall deflections and vertical ground surface settlements, can be successfully reproduced. The proposed approach represents a major shift in our ability to efficiently bridge numerical modeling and laboratory testing and change the way we approach soil characterization and constitutive model development. We can use very few laboratory tests to directly develop versatile material models that can be used in the solution of geotechnical field problems without the need for complex formulations or long development periods or calibration process. This is something that we have been unable to do before.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Civil Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Moon, Sungwoo

Contributors dc:contributor

• Hashash, Youssef M.
• Mesri, Gholamreza
• Olson, Scott M.
• Ghaboussi, Jamshid

• inverse analysis
• direct simple shear
• constitutive models
• soil behavior
• excavation

Statement dc:rights

• Copyright 2014 Sungwoo Moon

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/49670

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/49670