AIA 101 Agreement 08302024 - Laserfiche WebLink

Home Browse Search

June 13, 2023 HWA Project No. 2022-188-21 and are suitable for support of the proposed buildings. The site is also impacted by high ground water levels during the summer months due to irrigation. Details regarding our recommendations for design and construction of the proposed improvements are provided in the following sections. 4.2 SEISMIC DESIGN PARAMETERS The contribution of potential earthquake -induced ground motion from known sources is included in the probabilistic ground motion maps developed by the United States Geologic Survey (USGS). Design data seismic site characterization and design recommendations based on USGS mapping and analysis are implemented in the 2018 International Building Cade (IBC). As part of this code, the design of structures must consider dynamic forces resulting from seismic events. These forces are dependent upon the magnitude of the earthquake event as well as the properties of the soils that underlie the site. As part of the procedure to evaluate seismic forces, the 2018 IBC requires the evaluation of the Seismic Site Class, which categorizes the site based upon the characteristics of the subsurface profile 100 feet below the proposed foundation. The Site Class can then be determined in accordance with Section 20.3 of ASCE 7-16, and the corresponding values of Fa and Fv determined from Tables 11.4-1 and 11.4-2 of ASCE 7-16. In Section 11.4.8 of ASCE 7-16, it is stated that a site -specific ground motions hazard analysis is required on sites with seismically isolated structures and structures with dampening systems when Si greater than or equal to 0.6. Provided these conditions do not pertain to the proposed structures a site -specific hazard analysis is not required. Based on the obtained SPT blow counts noted in our boring logs and extrapolated to a depth of 100 feet, the site classifies as Site Class "C". Should the information used as a basis for this design be incorrect, HWA should be notified to provide appropriate recommendations. The associated probabilistic ground acceleration values and site coefficients for the general site area were obtained from the Applied Technology Council Seismic Hazard Maps. The risk targeted seismic values and coefficient are presented in Table 1 below. 2022-188-21 KCTS — Final Geotechnical Report 8 HWA GEOSCIENCES INC.