Source code for openquake.hazardlib.gsim.vanhoutte_2018

# -*- coding: utf-8 -*-
# vim: tabstop=4 shiftwidth=4 softtabstop=4
#
# Copyright (C) 2013-2022 GEM Foundation
#
# OpenQuake is free software: you can redistribute it and/or modify it
# under the terms of the GNU Affero General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# OpenQuake is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with OpenQuake. If not, see <http://www.gnu.org/licenses/>.

"""
Module exports :class:`VanHoutteEtAl2018RSD`
"""
import numpy as np

from openquake.hazardlib.gsim.base import CoeffsTable, GMPE
from openquake.hazardlib import const
from openquake.hazardlib.imt import RSD575


[docs]def get_magnitude_term(C, mag): """ Returns linear magnitude scaling term """ return C["b0"] + C["b1"] * (mag - 6) + C["b2"] * (mag - 6) ** 2
[docs]def get_distance_term(C, rrup, mag): """ Returns distance scaling term """ fac = rrup > 100 rmax100 = rrup.copy() rmax100[rmax100 > 100] = 100 fr = C["b3"] * np.log(np.sqrt( rmax100 ** 2 + (np.exp(C["b4"] + C["b5"] * (mag - 6))) ** 2)) + \ fac * ( C["b6"] * np.log(np.sqrt( rrup ** 2 + (np.exp(C["b4"] + C["b5"] * (mag - 6))) ** 2)) - C["b6"] * np.log(np.sqrt( 100 ** 2 + (np.exp(C["b4"] + C["b5"] * (mag - 6))) ** 2)) ) return fr
[docs]def get_site_amplification(C, vs30): """ Returns linear site amplification term """ return C["b7"] * np.log(vs30 / 1000)
[docs]class VanHoutteEtAl2018RSD(GMPE): """ Implements the GMPE of Van Houtte et al. (2018) for significant duration with 5 - 75 % Arias Intensity. doi:10.1785/0120170076. The oscillator duration model has not yet been implemented. """ #: Supported tectonic region type is active shallow crust DEFINED_FOR_TECTONIC_REGION_TYPE = const.TRT.ACTIVE_SHALLOW_CRUST #: Supported intensity measure types are 5 - 75 % Arias #: significant duration DEFINED_FOR_INTENSITY_MEASURE_TYPES = set([RSD575]) #: Supported intensity measure component is RotD50 DEFINED_FOR_INTENSITY_MEASURE_COMPONENT = const.IMC.AVERAGE_HORIZONTAL #: Supported standard deviation types are total, inter and intra-event DEFINED_FOR_STANDARD_DEVIATION_TYPES = { const.StdDev.TOTAL, const.StdDev.INTER_EVENT, const.StdDev.INTRA_EVENT} #: Requires vs30 REQUIRES_SITES_PARAMETERS = {'vs30'} #: Required rupture parameter is magnitude REQUIRES_RUPTURE_PARAMETERS = {'mag'} #: Required distance measure is closest distance to rupture REQUIRES_DISTANCES = {'rrup'}
[docs] def compute(self, ctx, imts, mean, sig, tau, phi): """ See :meth:`superclass method <.base.GroundShakingIntensityModel.compute>` for spec of input and result values. """ for m, imt in enumerate(imts): C = self.COEFFS[imt] mean[m] = (get_magnitude_term(C, ctx.mag) + get_distance_term(C, ctx.rrup, ctx.mag) + get_site_amplification(C, ctx.vs30)) sig[m] = np.sqrt(C["tau"] ** 2. + C["phi"] ** 2.) tau[m] = C["tau"] phi[m] = C["phi"]
COEFFS = CoeffsTable(sa_damping=5, table="""\ imt b0 b1 b2 b3 b4 b5 b6 b7 tau phi rsd575 -1.7204 0.2272 0.0967 0.8870 2.7641 0.5777 1.1700 -0.1413 0.2270 0.4163 """)