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Caribou Industries Proposed Alternative Seismic Improvements - 888 North Main Street July 25, 2018 Page 6 The site-specific BSE-2N and BSE-l N response spectra for 5% of critical structural damping are presented in Table 1 and Figures 2 and 3. The site-specific BSE-lE and probabilistic 50-in-50 geometric mean and maximum direction response spectra for 5% of critical structural damping are shown in Table 2 and Figures 4 and 5. 4.0 Period Range of Interest The fundamental building period of 1.4 seconds was provided by Mr. Leonard Martin Joseph of Thornton Tomasetti. The upper bound period of 2.1 seconds was selected equal to 1.5 times the largest fundamental period in accordance with Section 2.4.2.2 of ASCE/SEI 41-13. The lower bound period of 0.28 seconds was selected equal to 0.2 times the fundamental period. 5.0 Seed Time Histories We have used the four sets of acceleration-time histories previously selected and spectrally matched to the BSE- lE response spectrum for the NOVA Children's Academy (Amec Foster Wheeler, 2016). Each set of time histories consists of two orthogonal horizontal ground motion components. Each component of each set of time histories was scaled to the new BSE-lE and 50-in-50 response spectra such that the response spectrum closely matched the target spectrum. The scaling factor used for the BSE-l E target spectrum was 1.054 and the scaling factor used for the 50-in-50 target spectrum was 0.65. In Table 3, we present a total of four time history records that were scaled to the BSE-lE and 50-in-50 response spectra. Also presented in Table 3 are the earthquake magnitudes, fault mechanisms, source-to-site (Joyner- Boore - Rjb) distance, site Vs,30, lowest usable frequency, significant duration (Ds.95), and pulse period (Tp). The plots of acceleration, velocity and displacement time histories of the two components of the candidate time histories as well as the respective spectral acceleration and square root sum of the squares (SRSS) of the two orthogonal horizontal response spectra are shown on Figure 6.1.la through Figure 6.4.3 and Figure 8.1.la through Figure 8.4.3 for the BSE-lE hazard level and the 50-in-50 hazard level, respectively. The average of the 'Hl' and 'H2' horizontal components and average of the SRSS spectra are presented in Figures 7 and 9 for the BSE-lE hazard level and the 50-in-50 hazard level, respectively. The digital data for the time histories will be transmitted electronically. ...