Uncertainty Analysis in Dynamic Site and Slope Response

Implements a four-stage pipeline for probabilistic seismic performance analysis of slopes and embankments. The package takes a uniform-hazard spectrum at multiple return periods as input (any source) and produces: (1) synthetic soil profile generation and fundamental period estimation from USCS classification via Ishihara's small-strain shear-modulus model and the inhomogeneous truncated shear-beam theory of Gazetas and Dakoulas; (2) nonlinear site amplification using the NGA-East ergodic site-response models (Stewart et al. (2020) and Hashash et al. (2020) , with the 2017 PEER-report generation retained as an option), with inter-period correlation via Baker & Jayaram (2008) ; (3) Monte Carlo ensemble of six empirical Newmark sliding-block displacement models (Ambraseys & Menu (1988) , Jibson (2007) , Saygili & Rathje (2008) , Bray & Travasarou (2007) , Bray & Macedo (2017) , and the Bray and Macedo shallow-crustal update) with coherent correlated draws; (4) log-log inversion to the performance-based seismic coefficient kmax at user-specified displacement targets. All outputs are 'data.table' objects.

newmark

Overview

The package implements probabilistic propagation of seismic hazard uncertainty through the Newmark sliding-block displacement framework. Two stages of variability — the joint distribution of rock-level spectral demand from PSHA quantiles, and the conditional dispersion of empirical site-amplification and sliding-block models — are sampled via Gaussian copulas with mean-preserving recentering, and propagated to the mean, dispersion and design quantiles of the residual displacement Dn(ky) and the performance-based seismic coefficient kmax(d*).

Inputs are uniform-hazard spectra (UHS) at multiple return periods, produced by any external PSHA engine. Outputs are tabulated kmax(d*) and the normalised pseudostatic coefficient Kh = kmax / PGA at user-specified displacement targets, intended for performance-based seismic stability of slopes, embankments, tailings storage facilities and waste rock dumps.

Installation

# Stable release
install.packages("newmark")

# Development version
devtools::install_github("averriK/newmark")

Getting started

Four vignettes ship with the package:

vignette("newmark-quickstart",     package = "newmark")    # runnable hello world
vignette("pipeline",               package = "newmark")    # function-level overview
vignette("dynamic-site-response",  package = "newmark")    # Ts, stiffness profile, site amplification
vignette("ensemble-formulation",   package = "newmark")    # mathematical derivation

Function-level reference: ?fitSaF, ?getDnKy, ?fitDnCurve, ?invertDnDraws, ?getSiteProperties, ?geSiteTable, ?getCylinderRoots, ?fitModel.Ts, ?buildGMDP, ?Vs30toSID, ?SIDtoVs30, or help(package = "newmark").

Rendered documentation: https://averriK.github.io/newmark/.

Getting help

Open an issue at https://averriK.github.io/newmark/.

Citation

If you use this package in a publication, please cite the companion paper:

@unpublished{VerriKozlowski2026,
  author = {Verri Kozlowski, Alejandro},
  title  = {Probabilistic estimation of {Newmark} displacements and seismic
            coefficients under hazard uncertainty},
  year   = {2026},
  note   = {Working paper}
}

To cite the software package itself:

@Manual{Verri2026,
  title  = {{newmark}: Uncertainty Analysis in Dynamic Site and Slope Response},
  author = {Verri Kozlowski, Alejandro},
  year   = {2026},
  note   = {R package version 1.1.0},
  url    = {https://averriK.github.io/newmark/}
}

License

MIT — see LICENSE

Author

Alejandro Verri Kozlowski — [email protected]
ORCID 0000-0002-8535-1170
Universidad de Buenos Aires, Facultad de Ingeniería