Source code for openquake.hazardlib.gsim.gupta_2010

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"""
Module
:mod:`openquake.hazardlib.gsim.gupta_2010`
exports
:class:`Gupta2010SSlab`
"""

from openquake.hazardlib import const
from openquake.hazardlib.imt import PGA, SA
from openquake.hazardlib.gsim.base import CoeffsTable
from openquake.hazardlib.gsim.atkinson_boore_2003 \
    import AtkinsonBoore2003SSlab


[docs]class Gupta2010SSlab(AtkinsonBoore2003SSlab): # pylint: disable=too-few-public-methods """ Implements GMPE of Gupta (2010) for Indo-Burmese intraslab subduction. This model is closely related to the model of Atkinson & Boore (2003). In particular the functional form and coefficients ``C2``-``C7`` of Gupta (2010) are adopted from Atkinson & Boore (2003). The only substantive changes are a) the horizontal component modeled is different (as noted below) b) a coefficient ``C8`` and a dummy variable ``v`` are added to model vertical motion and c) the coefficient ``C1`` is recalculated based on a database of "a total of 56 three-component accelerograms at 37 different sites from three in-slab earthquakes along the Indo-Burmese subduction zone" (p 370). Equation (2) p. 373 gives the form of the equation which was fitted: ``log Y - C2*M - C3*h - C4*R + g log R = C1 + C8*v + sigma`` The left-hand side of this equation was computed using event parameters and the coefficients of Atkinson & Boore (2003). The regression coefficients C1 and C8 on the right-hand side were slightly smoothed after fitting. Note that since "v=0 for horizontal and 1 for vertical motion", and since the current implementation only models horizontal motion, we can subclass directly from :class:`openquake.hazardlib.gsim.atkinson_boore_2003.AtkinsonBoore2003SSlab`, modifying only the metadata constants and regression coefficients. Page number citations in this documentation refer to Gupta (2010). **References** Gupta, I. (2010). Response spectral attenuation relations for in-slab earthquakes in Indo-Burmese subduction zone. *Soil Dyn. Earthq. Eng.*, 30(5):368–377. Atkinson, G. M. and Boore, D. M. (2003). Empirical ground-motion relations for subduction-zone earthquakes and their application to Cascadia and other regions. *Bull. Seism. Soc. Am.*, 93(4):1703–1729. """ #: As stated in the title. DEFINED_FOR_TECTONIC_REGION_TYPE = const.TRT.SUBDUCTION_INTRASLAB #: "The actual peak ground acceleration (PGA) from the corrected time #: histories are taken as the response spectral amplitudes at a period of #: 0.02 s (50 Hz frequency)." p. 371. Based on this comment, the #: coefficients labeled as being for 0.02 s have been relabeld as PGA. DEFINED_FOR_INTENSITY_MEASURE_TYPES = {PGA, SA} #: Unlike Atkinson & Boore (2003), "rather than the random horizontal #: component, the geometric mean of both the horizontal components has #: been used in the modified attenuation relations." (p. 376) DEFINED_FOR_INTENSITY_MEASURE_COMPONENT = const.IMC.MEDIAN_HORIZONTAL #: Since the database is small only the total standard deviation is #: reported. DEFINED_FOR_STANDARD_DEVIATION_TYPES = {const.StdDev.TOTAL} #: Coefficients taken from Table 3, p. 884. The row for 0.02 was #: relabeled PGA since the paper indicates this is what it actually is #: (see p. 371) and since these were the coefficients for PGA in #: Atkinson & Boore (2003). COEFFS_SSLAB = CoeffsTable(sa_damping=5., table="""\ IMT c1 c2 c3 c4 c5 c6 c7 c8 sigma pga 0.4598 0.69090 0.01130 -0.00202 0.19 0.24 0.29 -0.3312 0.347 0.04 0.7382 0.63273 0.01275 -0.00234 0.15 0.20 0.20 -0.3090 0.343 0.10 1.0081 0.66675 0.01080 -0.00219 0.15 0.23 0.20 -0.3005 0.341 0.20 1.2227 0.69186 0.00572 -0.00192 0.15 0.27 0.25 -0.4001 0.340 0.40 0.8798 0.77270 0.00173 -0.00178 0.13 0.37 0.38 -0.4408 0.341 1.00 -0.3339 0.87890 0.00130 -0.00173 0.10 0.30 0.55 -0.3380 0.344 2.00 -2.0677 0.99640 0.00364 -0.00118 0.10 0.25 0.40 -0.2674 0.347 3.00 -3.4227 1.11690 0.00615 -0.00045 0.10 0.25 0.36 -0.3942 0.351 """) #: Mean value data obtained from author matched well at 1 s and below but #: not at longer periods. As a temporary measure the reference test result #: has been generated from the current implementation. non_verified = True