900 PACIFIC AVE WOMEN AND CHILDREN PAVILLION 2018-01-02 MF Import

I i I Providence Family Services Center �'91�'�-12M� August 25. 1999 Pape 11 � I • Excavation Setbacks: Any planned excavations for fooGngs, grade beams, underground utilities,or partial basements should maintain an adequate horizontai I setback from existing foundation elements. We should be allowed to review ail proposed excavation pians and peRinent as-built foundaGon plans on a case-by- c2se basis in orderto develop appropriate setback distances,underpinning criteria, Ior shoring wall pressures, as needed. • St u i Considerations: If a composite(pile/pier and footing)foundation system I is utilized,the building wouid likely exhibit differential motions during an earthquake, due to differences in the stiffness properties of each foundation type. This corxliGon couid be mitigated or possibly even eliminated by employing a rtwre-unifortn I foundation system. Specifically, the entire structure could be supported either on piles/piers,in which case the pile/pier lengths would vary considerably,oron spread footings,in which case it would be advantageous to inGude a deep basement below ! a portion of the building. The project structural engineer should be allowed to � evaluate the design and performance impiications of each foundation system. I • Seismic Considerations: Based on our literature reviev+ and subsu�face interpretations,we recommend that the project structural engineer use the following I seismic parameters as appropriate fordesign of buildings,retaining walis,and other site structures. If a future version of the UBC is to be used for structural design purposes, we should be retained to assist the project structural engineer in Ideveloping appropriate seismic criteria. Design Parameter Value I Acceleration Coefficient (1996 USG5) . 028 Risk Zone (1997 U8C) 3 Soil Profile Type (1997 UBC) S-C • On-Site Soil Reuse: Our visual soil Gacsifications and laboratory testing indicate i that most of the on-site soils are moderately to highiy moisture-sensitive and � susceptible to disturbance when wet. In order to maximize the potential for reusing on-site soits as structural fill, earthwork should be scheduled for periods of dry I weather, such as usually occur during the summer and early fall months. • Sub rade Protection: Due to the moisture-sensitive nature of the on-site soils,the I contractor should install appropriate temporary drainage systems to keep water out of the construction areas,and should minimize traffic overany subgrades prepared within these soils. , • Environmental Consid�rations: Although we did not encounter any obvious indications of environmental contaminants within the on-site soils, these negative S�WOROPROC'�59 Pro�eclf�5ea111e�1200Ci':":J RoO��so��ProviOen[e NosµRpl.w�pE '�J -7 I