Site Response
The purpose of this assignment is to investigate the SH-wave site
response function for a simple model.
Model:
The model consists of a single layer over a
halfspace with the following parameters:
Vs1 = 300 m/s, Vs2 = 3000 m/s, H=10 m,
Rho1=1200 kg/m3 and Rho2=2500 kg/m3
.
Problem 1:
Compute and plot the site amplification as a
function of frequency for frequencies between 0 and 20 Hz for the above
model. Assume that the SH wave is vertically incident.
Problem 2:
Modify problem 1 by permitting a Q=20 in the surface
layer.
Problem 3:
Compute the quarter-wavelength approximation of
Joyner and Boore (1997) and Boore (2003, PAGEOPH eqns 11-18) for
the same model, and plot together with the response of Problem
1.
Extra Credit:
- Write a program to compute the
quarter-wavelength response for a general input velocity model, using
the model96 format of Compute Programs in Seismology. For
generality, the command line should define the maximum and minimum
frequency range of interest, and source depth and/or the shear-wave
velocity and density at the source. A added aspect after this is
done correctly is to write out the equally spaced frequency response as
a sac file, for use with comparisons to real data