7920 EVERGREEN WAY 2018-01-01 MF Import

GEOTECHNICAL ENGINEEf G STUDY ; E 8�79 McDonald's Corporation Page 3 August 30, 1999 Structural fill is deiined as any compacted fill placed under buildings, roadways, slabs, pavements, or any other load bearing areas. Structural fill under floor slabs and fuotings shoi;ld be placed in thin horizontal lif:s not exceeding twe{ve (12) inches in loose thickness. Each lifc must be compacted to at least 90 percent of laboratory maximum dry density, determined in accordance with ASTM Test Designation D-1557-91 (Modified Proctor). Fill under pavements and walks should be placed in similar thin horizontal lifts and, with the exception of the upper twelve (12) inches, be compacted to at least 90 percent of maximum density. The top twelve (12) inches should be compacted to at least 95 percent maximum density. Durinc� dry weather, most soils which are compactible and non-organic can be used as structural fill. Based on the results of our laboratory tests, the on-site soils at the time of our exploration appear to near the optimum moisture content and should be suitable for use in their present condition as structural fill, provided the grading operations are co��ucted Juring dry weather. However, laboratory testing indicates the native soil has betwe� n 2"o and 28 percent fines passing the No. 200 sieve. Soil with fines in this range will degrade if exposed to excessive moisture, and compaction and grading will be difficult if the soil moisture increases significantly above its optimum condition. If the native soil is exposed to moisture and cannot be adequately cornpacted then it may be necessary to import a soil which can be compacted. During dry weather, most non-o�ganic compactible soil with a maximum particle size of six inches can be used. Fill for use during wet weather should consist of a fairly well graded gran�lar material having a maximum particie size of six inches and no more than five percent fines passing the No. 200 sieve based on the minus 3/4-inch fraction. A contingency in the earthwork budyet should be included for this possibility. Foundations Based on the results of our study, it is our opinion the proposed building may be supported on a conventional spread and continuous footing foundation bearing on the very dense native soils or on structural fill. For frost protection considerations, exterior foundation efements should be placed at a minimum depth of eighteen (18) inches below final exterior grade. Interior spread fcundations can be placed at a minimum depth of twelve (121 inches below the top of slab, except in unheated areas, where interior foundation elements should be founded at a minimum depth of eighteen (18) inches. With foundation support obtained as described, for design, an allowable bearing capacity of three thousand (3,000) psf for competent native soil or structural fill can be used. Continuous and individual spread footings shauld have minimum widths o� eighteen (18) and twenty-four (24) inches, respectively. Loading of this magnitude would be provided with a theoretical factor-of-safety in excess of three against actual shear failure. For short-term dynamic loading conditions, a one-third increase in the above allowable bearing capacities can be used. Earth Coneukente, Inc.