R is an open-source, object-oriented language and environment for computing that offers a wide availability of add-on user-contributed software codes (packages). The geotech R package is the first to perform a broad range of calculations that appear in geotechnical engineering education, research, and practice; its development was supported by a special project grant through the United States Universities Council and Geotechnical Education and Research (USUCGER). Note that the geotech R package is no longer actively updated on the R website, but files for installing and running the package are available below and at the geotech R package archive.
Kaklamanos, J., and K. T. Elmy (2016a). geotech: Geotechnical Engineering. R package version 1.0.
Kaklamanos, J., and K. T. Elmy (2016b). Development of a geotechnical engineering software package in R and its implementation in the civil engineering curriculum, Geotechnical and Structural Engineering Congress 2016, Phoenix, Arizona, 14-17 February 2016, American Society of Civil Engineers (ASCE), C. Y. Chandran and M. I. Hoit (eds)., pp. 635–647.
geotech R package web site
Reference manual (PDF)
Installation file (zip)
Kaklamanos and Elmy (2016) conference paper and presentation
USUCGER final summary report
Phase diagrams and index parameters
Grain size distributions
Plasticity
Soil classification
Subsurface exploration
Groundwater
Mohr circle analyses
Stress
Bearing capacity
Lateral earth pressures
Slope stability
Background plot functions
The nga R package is an implementation of the earthquake ground-motion models released in 2008 as part of the Next Generation Attenuation of Ground Motions (NGA-West 1) Project, using the open-source statistical language and environment R. Note that the nga R package is no longer actively updated on the R website, but files for installing and running the package are available below and at the nga R package archive.
Kaklamanos, J., and E. M. Thompson (2010). nga: NGA Ground Motion Prediction Equations. R package version 1.4-1.
Kaklamanos, J., D. M. Boore, E. M. Thompson, and K. W. Campbell (2010). Implementation of the Next Generation Attenuation (NGA) ground-motion prediction equations in Fortran and R, U.S. Geological Survey Open-File Report 2010-1296, 43 p.
nga R package web site
Reference manual (PDF)
Installation file (zip)
Kaklamanos et al. (2010) open-file report
Change log (PDF)
NGA (comprehensive functions for all models)
Abrahamson and Silva (2008)
Boore and Atkinson (2008)
Campbell and Bozorgnia (2008)
Chiou and Youngs (2008)
Miscellaneous Functions
We have developed Mathcad worksheets for the ground-motion models released in 2008 as part of the Next Generation Attenuation of Ground Motions (NGA-West 1) Project and in 2014 as part of the Enhancement of Next Generation Attenuation Relationships for Western U.S. (NGA-West 2) Project. Because the Mathcad worksheets present the equations in a highly visual, easy-to-comprehend framework, they allow for users to obtain a greater understanding of the models than otherwise possible, and also allow users to perform calculations on sub-portions of the models that are not readily available in other programs.
Blair, T. J., T. C. Cross, A. N. Moolacattu, B. M. Picard, and J. Kaklamanos (2016a). Implementation of the Next Generation Attenuation of Ground Motions (NGA-West 1) models in Mathcad. Merrimack College, North Andover, Mass.
Blair, T. J., T. C. Cross, A. N. Moolacattu, B. M. Picard, and J. Kaklamanos (2016b). Implementation of the Enhancement of Next Generation Attenuation Relationships for Western U.S. (NGA-West 2) models in Mathcad. Merrimack College, North Andover, Mass.
Abrahamson and Silva (2008)
Boore and Atkinson (2008)
Campbell and Bozorgnia (2008)
Chiou and Youngs (2008)
Idriss (2008)
Abrahamson, Silva, and Kamai (2014)
Boore, Stewart, Seyhan, and Atkinson (2014)
Campbell and Bozorgnia (2014)
Chiou and Youngs (2014)
Idriss (2014)
As part of the Kaklamanos et al. (2011) paper, we derived physical equations relating three earthquake distance parameters used in these ground-motion models: the rupture distance (RRUP), Joyner-Boore distance (RJB), and site coordinate (RX). The following electronic files are provided for implementing the physical distance equations.
Kaklamanos, J., L. G. Baise, and D. M. Boore (2011). Estimating unknown input parameters when implementing the NGA ground-motion prediction equations in engineering practice, Earthquake Spectra, Vol. 27, No. 4, pp. 1219–1235.
R script, using the open-source statistical language and environment R. This file may be opened using any text editor.
Mathcad worksheet, with various examples and numerical solutions for back-solving.
Microsoft Excel worksheet. When opening the document, please enable macros; otherwise, the worksheet will not function.