verification Spectral Intensity according to Housner (1952)

Calculate the spectral intensity as defined by Housner (1952) using OpenSeismoMatlab

Contents

Reference

Housner, G. W. (1952). Intensity of ground motion during strong earthquakes. California Institute of Technology, Second technical report, Office of naval research, task order 25, project NR-081-095.

Description

Table II on page 15 of the above reference is verified for the case of the El Centro, 1940 earthquake.The spectral intensity according to this table is 8.35ft for damping 0.0, 2.71ft for damping 0.2 and 1,89ft for damping 0.4. These values are verified with the present example

Load earthquake data

Earthquake acceleration time history of the El Centro earthquake will be used (El Centro, 1940, El Centro Terminal Substation Building)

fid=fopen('elcentro_NS_trunc.dat','r');
text=textscan(fid,'%f %f');
fclose(fid);
t=text{1,1};
dt=t(2)-t(1);
xgtt=text{1,2};

Calculate Housner Spectral Intensity

Switch

sw='SIH1952';

First value of damping (Table II in the above reference)

ksi1=0.0;

Second value of damping (Table II in the above reference)

ksi2=0.2;

Third value of damping (Table II in the above reference)

ksi3=0.4;

Apply OpenSeismoMatlab for calculating of the spectral intensity

S1=OpenSeismoMatlab(dt,xgtt,sw,ksi1);
S2=OpenSeismoMatlab(dt,xgtt,sw,ksi2);
S3=OpenSeismoMatlab(dt,xgtt,sw,ksi3);

Spectral intensities in ft

For damping 0.0

S1.SI*3.28084

ans =

          8.00634608331064

For damping 0.2

S2.SI*3.28084

ans =

          2.33622318056444

For damping 0.4

S3.SI*3.28084

ans =

          1.63462066423459

Copyright

Copyright (c) 2018-2023 by George Papazafeiropoulos

Published with MATLAB® R2022b