2825 COLBY AVE COLBY CENTER Geotech Report 2018-01-02 MF Import

_ ._ _ ____ _ GEOl'ECHNICAL ENGINEERING STUDY Mr. Arthur Skotdal � c/o Dykeman Architects E-6225 July 27, 1993 Page 6 -. Structural fill is defined as any compacted fill piaced under buildings, slabs, or any other load-bearing areas. Structural fill under floor slabs and footings should be placed in horizontal lifts not exceeding 12 inches in loose thic:kness and compacted to a minimum -� of 90 percent of its laboratory maximum dry density determined in accordance with ASTM Test Designation D-1557-78 (Modified Proctor). The fill materials should be placed at or near the optimum moisture content. Fill under pavements and walks should also be � placed in horizontal lifts and compacted to 90 percent of maximum density except for the top twelve (12) inches, which should be compacted to 95 percent of maximum density. -' During dry weather, most soiis which are compactibie and non-organic can be used as � �tructural fill. On-site soils at the time of our exploration were near the optimum moisture content and would be suitable for use in their present condition as structural fill. However, j the fine grained site soils will be moisture sensitive due to high fines content which ranges � from 20 to 49 percent, and will degrade if exposed to excessive moisture and construction traffic. Comp�action and grading will be difficult if the soil moisture in�reases Isignificantly above its optirnum condition. I If the native soil is exposed to moisture and cannot be adequately compacted then it may be ne�essary to use an imparted free-draining granular fiil. Fill for this purpose and for use in wet weather should consrst of a fairly well graded granular material having a maximum I size of three inches and no rnore than five percent fines passing the No. 200 sieve based on the minus 3/4-inch fraction. A contingency should be included in the earthwork budget for this possibility. IFoundations I Based on the results of our study, it is our opinion the proposed buildings can be supported on a conventional' spread footing foundation system bearing on the dense native soil. IExterior foundation elements ahould be placed a minimum depth of eighteen (18) inches �� -- below final exterior grade. Interior spread footings should be placed at a depth of + twelve (12) inches below the top of the slab. I I � I IEarth Consultants, Inc.