public void setParamDefaults()
{
stressDrop = StressDrop.SD_140;
siteType = HazardCalculation.ThisScenario.SiteType;
mag = HazardCalculation.ThisScenario.Magnitude;
rRup = HazardCalculation.ThisScenario.RuptureDistance;
updateCoeffs();
}
private static readonly double facv2 = -0.9295360; // ln(v2/vref)
private double getMean(int iper, SiteType st, StressDrop sd, double rRup, double mag)
{
double vs30 = (st == SiteType.HARD_ROCK) ? 2000 : 760;
// double sigma = 0.3 * sfac;
// double sigmaf = 1.0 / SQRT_2 / sigma;
double period = pd[iper];
// double H1 = Doubles.max(dtor(kk),2.0);
// double H1sq = H1*H1;
// if (magType == LG_PHASE) mag = Utils.mblgToMw(magConvCode, mag);
double gndm = c1[24] + c2[24] * mag + c3[24] * mag * mag; // pga
// reference
double gndmp = c1[iper] + c2[iper] * mag + c3[iper] * mag * mag;
double sf2;// , ie; ie apparantly not used
// if (ir > 2) { // 200 bar
if (sd == StressDrop.SD_200)
{
double diff = Math.Max(mag - m1[iper], 0.0);
// c sf2 is supposed to be eqn(6) of AB06 paper. Note use of Mw.
sf2 = stressfac *
Math.Min(del[iper] + 0.05, 0.05 + del[iper] * diff /
(mh[iper] - m1[iper]));
// ie = 2;
}
else
{
sf2 = 0.0;
// c default stress factor, use ie=1
// ie = 1;
}
// R=sqrt(rjb**2+H1sq)
// use rRup - NOTE min 2km for gridded, 5km for faults
// pga calculations
double rfac = Math.Log10(rRup);
double f0 = Math.Max(1.0 - rfac, 0.0);
double f1 = Math.Min(rfac, fac70);
double f2 = Math.Max(rfac - fac140, 0.0);
double gnd, S = 0;
// why this check; is there a NSHMP flag for negative vs?
if (vs30 > 0)
{
// compute pga on rock
gnd = gndm + (c4[24] + c5[24] * mag) * f1 +
(c6[24] + c7[24] * mag) * f2 + (c8[24] + c9[24] * mag) * f0 +
c10[24] * rRup + sf2;
// apply stress factor before nonlinear adjustments, which occur
// in eqn (7) of ab paper
double bnl;
if (vs30 <= v1)
{
bnl = b1[iper];
}
else if (vs30 <= v2)
{
bnl = (b1[iper] - b2[iper]) * Math.Log(vs30 / v2) / facv1 +
b1[iper];
}
else if (vs30 <= vref)
{
bnl = b2[iper] * Math.Log(vs30 / vref) / facv2;
}
else
{
bnl = 0.0;
}
double pga_bc = Math.Pow(10, gnd);
if (st == SiteType.HARD_ROCK)
{
S = 0.0;
}
else if (pga_bc <= 60.0)
{
S = bln[iper] * Math.Log(vs30 / vref) + bnl * tfac;
}
else
{
S = bln[iper] * Math.Log(vs30 / vref) + bnl *
Math.Log(pga_bc / 100.0);
}
// need to take alog10(exp(S)) according to eqns. 7a and 7b
// AB2006. p. 2200 BSSA (new nov 26 2007)
S = Math.Log10(Math.Exp(S));
}
gnd = gndmp + (c4[iper] + c5[iper] * mag) * f1 +
(c6[iper] + c7[iper] * mag) * f2 + (c8[iper] + c9[iper] * mag) *
f0 + c10[iper] * rRup + sf2 + S;
if (iper < 26)
{
gnd = gnd * sfac - gfac;
}
else
{
// pgv?
gnd = gnd * sfac;
}
return(gnd);
}
