Geotechnical Info .Com provides various earthquake parameters that
geotechnical engineers use and calculations for determining the potential
for liquefaction in the Earthquake Technical Guidance. If you need more information than what is currently
provided here, then post a question in the
- Soil Dynamics and Special Design Aspects. Main topics include soil dynamics,
earthquake engineering and special design aspects. Information pertaining to these topics
include machine foundations, impact loadings, dynamic soil properties, slope stability,
bearing capacity, settlement, vibratory compaction, pile driving analysis and field testing,
ground anchor systems, seismic design parameters, liquefaction, sheet pile walls and laboratory
TM 5-852-4 - Arctic and Subarctic Construction - Foundations for Structures
EM 1110-1-1905 - Bearing Capacity of Soils
USACE EM 1110-2-2906 - Design of Pile
Foundations. Note: This publication does not have an appendix. For link to appendix,
USACE EM 1110-2-2200 -
Gravity Dam Design. Includes evaluation of existing dams, foundation parameters, concrete
properties, loads, stability analysis, structural design considerations, construction
considerations and static/ dynamic stress analysis.
USACE EM 1110-2-2502
- Retaining and Flood Walls. Note: This publication does not have an appendix. For link to appendix,
USACE EM 1110-1-2908 - Rock
USACE EM 1110-1-1904 - Settlement
USACE EM 1110-2-1902 - Slope
Stability. Note: This publication does not have an appendix. For link to appendix,
USACE TM 5-818-1 - Soils and Geology Procedures
for Foundation Design of Buildings and Other Structures (Except Hydraulic Structures)
References to Earthquake Engineering in other Publications
Edinger, P.H., "Seismic Response Consideration in Foundation Design,"Foundation
Engineering: Current Principles and Practices, Northwestern University, Kulhawy,
Vol. 1, pp 814-824, ASCE, New York, 1989.
Tokimatsu, K., Seed, H.B. "Evaluation of Settlements in Sands due to Earthquake
Shaking," Journal of Geotechnical Engineering, Vol. 113, pp 861-878, ASCE,
New York, 1987.
Shake2000 - Ground acceleration analysis.
Earthquake engineering for retaining walls
Review the detailed information, equations, and calculations in the Retaining Walls
Maximum ground acceleration
The maximum ground acceleration for different geographical regions in the United States may be estimated from the
United States Seismic Zones Map here.
Soil class and spectral response
Site classifications based on general soil types may be derived from this link. In
addition, relationships between general soil types and spectral response accelerations are provided.
Liquefaction Assessment (from NAVFAC)
Liquefaction basically occurs during an earthquake in which the soil behaves
like a liquid. Poorly graded sands below the water table are most
susceptible. Silts and gravels have a lower potential for liquefaction.
Usually, liquefaction is not a problem when ideal conditions exist at a
depth greater than 50 feet below the ground surface. The liquefaction
calculations provided below utilizes the Standard Penetration Test (SPT).
NAVFAC also has a method for Cone Penetrometer Test (CPT). See publications
F.S. = CRR > 1.2
F.S. = Factor of safety for liquefaction. Usually a F.S. greater than
1.2 is acceptable for liquefaction.
CRR = Cyclic Resistance Ratio. Factor derived from NAVFAC
CRR Chart. Need corrected N-value, (N1)60.
Chart is based on earthquake magnitude of 7.5. Multiply CRR by
for other earthquake magnitudes.
CSR = 0.65 amax
(N1)60 = CN(ERm) N
CN = overburden correlation from NAVFAC
CN chart. Based on
ERm = energy ratio (%) from NAVFAC
N = N-value from SPT test
amax = peak horizontal
acceleration of earthquake, g's
g = 32.2 ft/sec2 = gravitational constant
s = total overburden stress above
liquefiable soils, lb/ft2
*see notes below
effective overburden stress above liquefiable soils, lb/ft2
*see notes below
= stress reduction factor
= 1.0 if liquefiable soils are at ground surface
= 0.9 if top of liquefiable soils are at a depth of 30 ft below the ground
Notes: Total and effective overburden stress may be calculated from the
and stress guidance.
If you found this website useful, then Tell a friend!