Source code for openquake.hazardlib.gsim.bahrampouri_2021_duration

# -*- coding: utf-8 -*-
# vim: tabstop=4 shiftwidth=4 softtabstop=4
#
# Copyright (C) 2013-2022 GEM Foundation
#
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# 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.
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"""
Module exports :class:`BahrampouriEtAldm2021`
               :class:`BahrampouriEtAldm2021ASC`
               :class:`BahrampouriEtAldm2021SSlab`
               :class:`BahrampouriEtAldm2021SInter`
"""
import numpy as np
from openquake.hazardlib.gsim.base import CoeffsTable, GMPE
from openquake.hazardlib import const
from openquake.hazardlib.imt import RSD595, RSD575


def _get_source_term(C, ctx):
    """
    Compute the source term described in Eq. 8:
    `` 10.^(m1*(M-m2))+m3``
    m3 = varies as per focal mechanism for ASC and Slab TRTs
    """
    if ctx.rake <= -45.0 and ctx.rake >= -135.0:
        # Normal faulting
        m3 = C["m3_NS"]

    elif ctx.rake >= 45.0 and ctx.rake <= 135.0:
        # Reverse faulting
        m3 = C["m3_RS"]
    else:
        # No adjustment for strike-slip faulting
        m3 = C["m3_SS"]
    fsource = round(10**(C['m1'] * (ctx.mag-C['m2'])) + m3, 4)
    return fsource


def _get_path_term(C, ctx):
    """
    Implementing Eqs. 9, 10 and 11
    """
    slope = C['r1'] + C['r2']*(ctx.mag-4.0)

    if ctx.mag > C['M2']:
        mse = 1
    elif ctx.mag <= C['M1']:
        mse = 0
    else:
        mse = ((ctx.mag - C['M1'])/(C['M2'] - C['M1']))
    fpath = np.round(slope * ctx.rrup, 4)
    idx = ctx.rrup > C['R1']
    fpath[idx] = np.round(slope * (C['R1']+(mse*(ctx.rrup[idx] - C['R1']))), 4)
    return fpath


def _get_site_term(C, ctx):
    """
    Implementing Eqs. 5, 6 and 12
    """
    mean_z1pt0 = (np.exp(((-5.23 / 2.) * np.log(((ctx.vs30 ** 2.) +
                  412.39 ** 2.) / (1360 ** 2. + 412.39 ** 2.)))-0.9))
    delta_z1pt0 = np.round(ctx.z1pt0 - mean_z1pt0, 4)
    fsite = []
    for i, value in enumerate(delta_z1pt0):
        s = (np.round(C['s1']*np.log(min(ctx.vs30[i], 600.)/600.) +
             C['s2']*min(delta_z1pt0[i], 250.0) + C['s3'], 4))
        fsite.append(s)
    return fsite


def _get_stddevs(C):
    """
    The authors have provided the values of
    sigma = np.sqrt(tau**2+phi_ss**2+phi_s2s**2)
    The within event term (phi) has been calculated by
    combining the phi_ss and phi_s2s
    """
    sig = C['sig']
    tau = C['tau']
    phi = np.sqrt(C['phi_ss']**2 + C['phi_s2s']**2)
    return sig, tau, phi


[docs]class BahrampouriEtAldm2021Asc(GMPE): """ Implements GMPE by Mahdi Bahrampouri, Adrian Rodriguez-Marek and Russell A Green developed from the KiK-net database. This GMPE is specifically derived for significant durations: Ds5-Ds95,D25-Ds75. This GMPE is described in a paper published in 2021 on Earthquake Spectra, Volume 37, Pg 903-920 and titled 'Ground motion prediction equations for significant duration using the KiK-net database'. """ #: Supported tectonic region type is active shallow crust DEFINED_FOR_TECTONIC_REGION_TYPE = const.TRT.ACTIVE_SHALLOW_CRUST #: Supported intensity measure types are 5 - 95 % Arias and 5 - 75 % Arias #: significant duration DEFINED_FOR_INTENSITY_MEASURE_TYPES = {RSD595, RSD575} #: Supported intensity measure component is the geometric mean horizontal #: component DEFINED_FOR_INTENSITY_MEASURE_COMPONENT = const.IMC.AVERAGE_HORIZONTAL #: Supported standard deviation type is only total, see table 7, page 35 DEFINED_FOR_STANDARD_DEVIATION_TYPES = { const.StdDev.TOTAL, const.StdDev.INTER_EVENT, const.StdDev.INTRA_EVENT} #: Requires vs30 REQUIRES_SITES_PARAMETERS = {'vs30', 'z1pt0'} #: Required rupture parameters are magnitude and top of rupture depth REQUIRES_RUPTURE_PARAMETERS = {'mag', 'rake'} #: 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] = np.log(_get_source_term(C, ctx) + _get_path_term(C, ctx)) + _get_site_term(C, ctx) sig[m], tau[m], phi[m] = _get_stddevs(C)
COEFFS = CoeffsTable(table=""" imt m1 m2 m3_RS m3_SS m3_NS M1 M2 r1 r2 R1 s1 s2 s3 sig tau phi_s2s phi_ss rsd595  0.6899  6.511   4.584 4.252 5.522   4. 6.5  0.21960   0. 60.  -0.3008  0.00119  -0.1107 0.462 0.204 0.185 0.370 rsd575  0.7966  6.5107 0.06828 0.2902 0.613 4. 6.5 0.1248 0. 60.  -0.1894 0.0003362 -0.03979 0.586 0.233 0.223 0.490 """)
[docs]class BahrampouriEtAldm2021SSlab(GMPE): """ Implements GMPE by Mahdi Bahrampouri, Adrian Rodriguez-Marek and Russell A Green developed from the KiK-net database. This GMPE is specifically derived for significant durations: Ds5-Ds95,D25-Ds75. This GMPE is described in a paper published in 2021 on Earthquake Spectra, Volume 37, Pg 903-920 and titled 'Ground motion prediction equations for significant duration using the KiK-net database'. """ #: Supported tectonic region type is active shallow crust DEFINED_FOR_TECTONIC_REGION_TYPE = const.TRT.SUBDUCTION_INTRASLAB #: Supported intensity measure types are 5 - 95 % Arias and 5 - 75 % Arias #: significant duration DEFINED_FOR_INTENSITY_MEASURE_TYPES = {RSD595, RSD575} #: Supported intensity measure component is the geometric mean horizontal #: component DEFINED_FOR_INTENSITY_MEASURE_COMPONENT = const.IMC.AVERAGE_HORIZONTAL #: Supported standard deviation type is only total, see table 7, page 35 DEFINED_FOR_STANDARD_DEVIATION_TYPES = { const.StdDev.TOTAL, const.StdDev.INTER_EVENT, const.StdDev.INTRA_EVENT} #: Requires vs30 REQUIRES_SITES_PARAMETERS = {'vs30', 'z1pt0'} #: Required rupture parameters are magnitude and top of rupture depth REQUIRES_RUPTURE_PARAMETERS = {'mag', 'rake'} #: 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] = np.log(_get_source_term(C, ctx) + _get_path_term(C, ctx)) + _get_site_term(C, ctx) sig[m], tau[m], phi[m] = _get_stddevs(C)
COEFFS = CoeffsTable(sa_damping=5, table=""" imt m1 m2 m3_RS m3_SS m3_NS M1 M2 r1 r2 R1 s1 s2 s3 sig tau phi_s2s phi_ss rsd595  0.385 4.1604 5.828 4.231 5.496 5.5 8.0 0.09936 0.02495 200.0 -0.244 0.001409 -0.04109 0.458 0.194 0.245 0.335 rsd575  0.4232 5.1674 0.975 0.3965 0.8712 5.0 8.0 0.057576 0.01316 200.0 -0.1431 0.001440 0.04534 0.593 0.261 0.288 0.449 """)
[docs]class BahrampouriEtAldm2021SInter(GMPE): """ Implements GMPE by Mahdi Bahrampouri, Adrian Rodriguez-Marek and Russell A Green developed from the KiK-net database. This GMPE is specifically derived for significant durations: Ds5-Ds95,D25-Ds75. This GMPE is described in a paper published in 2021 on Earthquake Spectra, Volume 37, Pg 903-920 and titled 'Ground motion prediction equations for significant duration using the KiK-net database'. """ #: Supported tectonic region type is active shallow crust DEFINED_FOR_TECTONIC_REGION_TYPE = const.TRT.SUBDUCTION_INTERFACE #: Supported intensity measure types are 5 - 95 % Arias and 5 - 75 % Arias #: significant duration DEFINED_FOR_INTENSITY_MEASURE_TYPES = {RSD595, RSD575} #: Supported intensity measure component is the geometric mean horizontal #: component DEFINED_FOR_INTENSITY_MEASURE_COMPONENT = const.IMC.AVERAGE_HORIZONTAL #: Supported standard deviation type is only total, see table 7, page 35 DEFINED_FOR_STANDARD_DEVIATION_TYPES = { const.StdDev.TOTAL, const.StdDev.INTER_EVENT, const.StdDev.INTRA_EVENT} #: Requires vs30 REQUIRES_SITES_PARAMETERS = {'vs30', 'z1pt0'} #: Required rupture parameters are magnitude and top of rupture depth REQUIRES_RUPTURE_PARAMETERS = {'mag', 'rake'} #: 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] = np.log(_get_source_term(C, ctx) + _get_path_term(C, ctx)) + _get_site_term(C, ctx) sig[m], tau[m], phi[m] = _get_stddevs(C)
COEFFS = CoeffsTable(sa_damping=5, table=""" imt m1 m2 m3_RS M1 M2 r1 r2 R1 s1 s2 s3 sig tau phi_s2s phi_ss rsd595  0.2384 4.16 8.4117 5.5 8.0 0.08862 0.04194 200.0 -0.2875 0.001234 -0.03137 0.403 0.191 0.233 0.275 rsd575  0.4733 6.1623 0.515 5.0 8.0 0.07505 0.0156 200.0 -0.1464 0.00075 0.357 0.490 0.218 0.238 0.369 """)