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D. Foundations <br />Our foundation design assumptions include a minimum factor of safety of 3 with <br />respect to localized shear or base failure of the foundations. We assume the structure will <br />be able to tolerate total settlements up to one (1) inch, and differential settlements over <br />thirty (30) feet distance of up to one -half (%:) inch. <br />We understand the proposed building will be one -story slab on grade. Building <br />and loading information was not provided. Based upon similar structures, we assume <br />bearing wall loads of up to 6 kips per lineal foot and column loads of up to 125 kips. We <br />also assume that maximum floor loads will not exceed 300 psf. <br />Based upon the soil conditions encountered, it is our opinion the building <br />foundations can be designed on a maximum allowable soil bearing pressure of 2000 <br />psf, based upon that all unsuitable soil material be excavated, as discussed above, <br />and that the footings be set on engineered fill, see Table I. <br />All fill supporting the foundations should be compacted to a minimum of 95% of <br />Standard Proctor density. This 95% compaction requirement includes utility, floor slab <br />and foundation trench backfill. It is our judgement this design pressure will have a factor <br />of safety of at least 3 against localized shear or base failure. We judge that total <br />settlements under this loading should not exceed 1 ". We also judge that differential <br />settlements of conditions depicted by the borings should not exceed one -half (%) inch <br />over thirty (30) feet distance. <br />We recommended for footings under heated building that all frost footings be <br />placed at a minimum of 4 feet (48 inches) below ground.. We recommend for all areas of <br />building not heated that all frost footings be placed a minimum of 5 feet (60 inches) below <br />ground. <br />If any other footing arrangements or alternatives are considered, if foundation <br />loadings are higher, or if soils of a significantly different nature are discovered during <br />excavations, the office of SPC Engineering & Testing, Inc. should be contacted for re- <br />analysis. <br />E. Slabs <br />Slabs should also rest upon and over mineral soil of adequate density. This density <br />needs only to be sufficient to control settlement potential. The maximum floor loads will <br />not exceed 300 psf. <br />Based upon boring evidence, base mineral soils on the site are adequate for slab support <br />when; <br />a) Garage and Floor concrete slabs should rest on controlled fill (compacted, <br />and tested), see Table I. <br />