% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/F_models.R
\name{SaF_ST17}
\alias{SaF_ST17}
\title{Site-amplified spectral acceleration using Seyhan & Stewart (2014)}
\usage{
SaF_ST17(Sa, pga, Tn, vs30, vref = 760)
}
\arguments{
\item{Sa}{numeric vector - rock spectral accelerations at period Tn (g)}

\item{pga}{numeric vector - peak ground acceleration on rock (g), same length as Sa}

\item{Tn}{numeric scalar - oscillator period (s)}

\item{vs30}{numeric scalar - time-averaged shear-wave velocity to 30 m (m/s)}

\item{vref}{numeric scalar - reference velocity (m/s), default 760}
}
\value{
A \link[data.table]{data.table} with columns:
\describe{
\item{\code{muLnSaF}}{natural-log mean of amplified Sa}
\item{\code{sdLnSaF}}{natural-log standard deviation of amplified Sa}
\item{\code{ID}}{character string "ST17"}}
}
\description{
Computes site-amplified spectral acceleration Sa_F using the Seyhan & Stewart (2014)
non-linear site factor model. This is the canonical implementation that calls
the underlying F_ST17() function.
}
\section{References}{

Seyhan, E. & Stewart, J.P. (2014) "Semi-empirical nonlinear site amplification
from NGA-West2 data and simulations." \emph{Earthquake Spectra} \strong{30}(3):1241--1256.
\doi{10.1193/063013EQS181M}
}

\examples{
library(data.table)

# Site amplification for soft soil site
Sa_rock <- c(0.1, 0.2, 0.3, 0.4)
PGA_rock <- c(0.1, 0.1, 0.1, 0.1)

result <- SaF_ST17(
  Sa = Sa_rock,
  pga = PGA_rock,
  Tn = 0.5,      # 0.5s period
  vs30 = 300,    # Soft soil
  vref = 760     # Rock reference
)

print(result)
}
\seealso{
\code{\link{F_ST17}} for the underlying site factor model

\code{\link{fitSaF}} for Monte-Carlo site amplification analysis
}
