SHI Builders West Orange NJ Prelim GI SWM Report 1

should be sized no less than minimum dimensions of 24 inches for continuous wall footings and 36 inches for isolated column footings. Footings subject to tension loads should be designed so that the maximum toe pressure due to the combined effect of vertical loads and overturning moment does not exceed the recommended maximum allowable net bearing pressure recommended above. In addition, positive contact pressure should be maintained throughout the base of the footings such that no uplift or tension exists between the base of the footings and the supporting soil. Uplift loads should be resisted by the weight of the concrete, side friction (vertical along the footer) should be neglected. Lateral resistance should be provided by friction on the base of the footing with a recommended coefficient of friction against sliding:  Formed concrete on gravel subbase material – 0.40;  Mass concrete on gravel subbase material – 0.50; and  Mass concrete on on-site natural soils - 0.30. Partial Rock Support: Footings should not bear partially on rock and partially on soil due to the risk of brittle fracture at hinging points. Any foundation subgrades that would result in partially supported rock conditions should be overexcavated an additional six inches and replaced with well graded, compacted structural fill to provide a cushion against brittle fracture. Alternatively, isolated spread footings (if applicable) may be extended to bear entirely on rock. Inspection/Overexcavation Criteria: The suitability of the bearing soils along and below the footing bottoms must be verified by Dynamic Earth’s geotechnical engineer prior to placing concrete, especially to confirm that unsuitable materials are removed and new fills are adequately placed and compacted. Any overexcavation to be restored with structural fill (on-site or imported) will need to extend at least one foot laterally beyond footing edges for each vertical foot of overexcavation. The bottom of overexcavations should be compacted with smooth drum rollers, walk-behind compactors, vibrating plates or plate tampers (“jumping jacks”) to compact locally disturbed materials and densify underlying natural soil zones. Unsuitable materials should be overexcavated prior to placing new fill materials where site grades are to be raised. The extent of overexcavation can be estimated based on an evaluation

soil zones. Unsuitable materials should be overexcavated prior to placing new fill materials where site grades are to be raised. The extent of overexcavation can be estimated based on an evaluation of the final site grading plans, structural loading conditions, foundation plans, and supplemental geotechnical investigation. Furthermore, the proposed building footprint/interior column foundation locations should be located by a professional surveyor prior to performing overexcavation operations. Settlement: Once design loading conditions have been determined, settlement evaluation associated with the proposed structure will be required as part of the final evaluation. SHI Builders 9 4266-99-001E