|
Lutzky Associates Development. LP - Geotechnical invescigation
<br />MACTEC Project 4953-03-2631
<br />September 18. 2003
<br />Section 1659.4.2 of the 2001 CBC states that the motions shall be scaled such that the average
<br />value of the square root of the sum of the squares (SRSS) spectra does not fall below 1.3 times the
<br />DBE (or UBE) spectrum by more than 10 percent for the periods of interest. A period range of 0.1
<br />second to 3.5 seconds was provided by the structural engineer. Therefore, a target spectra of 90%
<br />DBE (or UBE) was used, so that, the SRSS spectra could be approximately 10% lower than the 1.3
<br />times the DBE (or UBE) spectra.
<br />Table 7, Modified Orthogonal Horizontal Components, identifies the horizontal components for
<br />each record listed in Table 6 and presents initial and modified peak ground acceleration (PGA)
<br />values.
<br />Response spectra for the original and the modified time histories and the 90% of DBE (target
<br />spectrum) for one orthogonal horizontal component are presented in Figures 9.1,10.1,11.1,12.1,
<br />13.1, 14.1, and 15.1 and for the other orthogonal horizontal component in Figures 9.3,10.3,11.3,
<br />12.3, 13.3,14.3, and 15.3. Response spectra for the original and the modified time histories and
<br />the 90% of UBE (target spectrum) for one orthogonal horizontal component are presented in
<br />Figures 9.6, 10.6, 11.6, 12.6, 13.6, 14.6, and 15.6 and for the other orthogonal horizontal
<br />component in Figures 9.8,10.8,11.8,12.8, 13.8,14.8, and 15.8.
<br />Acceleration, velocity and displacement time histories for the original records and the modified
<br />time histories, for DBE matching, for one orthogonal horizontal component are presented in
<br />Figures 9.2, 10.2, 11.2, 12.2, 13.2, 14.2, and 15.2 and for the other orthogonal horizontal
<br />component in Figures 9.4, 10.4, 11.4, 12.4, 13.4, 14.4, and 15.4. Acceleration, velocity and
<br />displacement time histories for the original records and the modified time histories, for UBE
<br />matching, for one orthogonal horizontal component are presented in Figures 9.7,10.7,11.7,12.7,
<br />13.7,14.7, and 15.7 and for the other orthogonal horizontal component in Figures 9.9,10.9,11.9,
<br />12.9,13.9,14.9, and 15.9.
<br />The SRSS and the 90% of 1.3 times the DBE spectrum are presented in Figures 9.5,10.5,11.5,
<br />12.5, 13.5, 14.5, and 15.5. The SRSS and the 90% of 1.3 times the UBE spectrum are presented in
<br />Figures 9.10,10.10,11.10,12.10,13.10,14.10, and 15.10.
<br />24
|