1716 EDGEMOOR LN 2016-01-01 MF Import

Roth Quality Homes JN 90016 January 25 , 1990 Page 4 The site soils are .generally silts , which are sensitive to changes in moisture content. Grading of silts is difficult to impossible to accomplish when they are wet. It is preferable that development of this site occur during the dry summer months when site work will be less difficult. Gn�uvcnimTnninr. F'nnNDATIONS The proposed structure can be supported on conventional continuous and spread footings keyed into native, hard silts . The northern, downslope footings should be embedded at least two ( 2 ) feet into the competent native silt. These foundations should bear directly on the competent silt. Continuous and individual spread footings should have minimum widths of twelve ( 12) and sixteen ( 16 ) inches , respectively, and should be bottomed at least twelve ( 12 ) inches below the lowest adjacent finish ground surEace. Unless lean concrete is used to fill overexcavations below the upslope footings , the width of the overexcavation at the bottom must be at least as wide as the sum of the depth of the overexcavation and the footing width. For example, an overexcavation extending two feet below the bottom of a 3- foot-wide footing must be at least five feet wide at the .,ase of the excavation. Footings constructed according to the above recommendations may be designed for an allowable soil bearing pressure of two thousand (2000 ) pounds per square foot (psf ) . A one-third increase in this design bearing pressure may be used when considering short-term wind or seismic loads . For the above design criteria , it is anticipated that total post- construction settlement of footings founded on competent, native .soils or on structural fill up to five (5 ) feet in thickness will be about one-half inch, with differential settlements between adjacent isolated footings of less than one-half inch. Lateral loads due to wind or seismic forces may be resisted by friction between the foundations and the bearinc� soils , or by passive earth pressure acting on the vertical , embedded portions of the foundatior . For the latter condition, the foundations must either be poured directly against level , undisturbed soil or level structural fill must be placed GEOTECH CONSULTANTS , INC.