Dear Geotechnical Colleagues working
around the
You are warmly invited to attend a seminar
to be given by Prof. John Atkinson, Professor of Soil Mechanics,
Thank you for your attention.
regards,
Ian
Soil Parameters for Geotechnical
Design
John Atkinson, BSc, ACGI, MSc, DIC, PhD, FICE, CEng, FGS,
CGeol.
Professor of Soil Mechanics,
Visiting Senior Principal, Coffey Geotechnics.
Synopsis.
Geotechnical design
requires analyses for stability (ultimate limit states) and ground movements
(serviceability limit sates). These analyses need input of numerical values for
soil parameters for strength and stiffness. They also require input of factors,
global or partial, and assessment of performance. Values for parameters and
factors are inter-related and both depend on the nature of the structure and
the limit state being considered.
Some soil parameters are
material parameters; they depend only on the soil grains and are independent of
the water content or relative density. Some soil parameters are state dependent
and they depend both on the soil grains and on the state of the soil. These
dependencies provide rapid assessments of reasonable values for many common
soil parameters.
The lecture will firstly
consider which parameters are required for different analyses; it will consider
particularly choices between peak, ultimate and residual strengths and the
importance of non-linear stiffness. Secondly it will consider relationships
between material parameters and simple classification tests and the variations
of parameter values with state.
The lecture will
demonstrate that different designs require different parameters and different factors
and, for each case, there are key parameters which should be determined. Many
important soil parameters can be estimated from simple classification tests.