6605 HARDESON RD BASE FILE 2016-01-01 MF Import

Intracorp September 21, 1998 E-3592-720 Pape 5 Based on the encountared subsurface soil conditions, preliminary de:,ign criteria and assumfnp compliance with the preceding Site Preparation and Grading section, the propo;;ed warehouse may be supported on conventional spread and coiiti�uous footing foundation systema bearing on the competent native soil or on structural fill placed to modify existin� sitc: grades. For frost protection, exterior foundations elements should be placed at a minimum depth of eighteen, (18) inches belc�nr final exterior grade. interior spread footings �can be pla�:ed at a minimum depth of twelve (12) inches below the top of slab, except in unhoated areas, where interior foundation elements should be founded at e minimum depth of eighteen (18) inches. Continuous and individual spread footings should have minimum widths of eighteen (18) and twenty-four (24) inches, respectively. With faundation support obtained as described, footings may be designed for an ailowablo soil bearing capacity of three thousand (3,000) psf for competent native so,l, existing fill, or structural fill. Loading of this magnitude wouid be provided with a theoretic�il factor-of-safety in excess of three against actual shear failure. For short-term dynamic loading conditions, a one-third increase in the above allowabie bearing capacities can be used. Horizontal loads can be resisted by friction between the base of the foundation and the supporting soil and by passive soil pressure acting on the face of the buried portion of the foundation. For the latter, the foundation must be poured "neat" agai�st competent native soils or backfilled with structural fili. For frictional capacity, a coefficient of .35 can be used. For passive earth pressure, the available resistance can be computed using an equivalent flufd pressure of three hundred fifty (350) pcf. These lateral resistance values are allowable values, a factor-of-safety of 1.5 has been included. As movement of the foundation element is required to mobilize full passive resistance, the passive resistance shoutd be neglected if such movement is not acceptable. Footing excavations should be observed by a representative of ECI, prior to placing forms or rebar, ta verify conditions are as anticipated in this report. Slab-on-Grade Floors Slab-on-grade floors may be supported on competent native soils or on structural fill used to modify site grades. Where loose soil is encountered at the slab subgrade elevation, the loose soil should be compacted to the previously discussed requirements for structural fill. Disturbed subgrade soils should either be recompacted or replaced with structural fill. Concrete slabs should be provided with a minimum of four inches of free-draining sand or gravel. In areas where slab moisture is undesirable, a vapor barrier such as a 6-mil plastic membrane may be placed beneath the slab. Two inches of damp sand may be placed over the membrane for protection during construction and to aid in curing of the concrete. Erth Corouhrm. Inc.