8.3 SR 04-04-2022 - Laserfiche WebLink

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March 2, 2020 Project 19-460 Jackson Hills Residential Suite Phases II- IV Elk River, Minnesota Any footings placed on native soils or on properly compacted fill should be proportioned for a maximum net allowable soil bearing pressure of 2000 psf. We recommend compaction tests be taken on any fill below the footings at a rate of one test per 50 linear feet for wall footings and one test per column footing. We recommend compaction tests be taken immediately prior to pouring the footings. The recommended bearing pressure is a net value and represents the actual loads that may be transmitted to the soil independent of overburden pressures. We estimate total settlement to be less than 1 inch with differential settlement about half of this if the recommendations in this report are followed. Floor Slab We recommend a minimum of 6 inches of clean, free draining washed sand with less than 5% passing a No. 200 sieve be placed beneath the floor slabs. This will provide a capillary break and a uniform level subgrade for the floor slabs. We recommend floor slabs be designed using a modulus of subgrade reaction of 300 pounds per cubic inch. We recommend a vapor moisture barrier consisting of minimum 6-mil polyethylene sheeting. A vapor barrier should be placed under all concrete floors on ground that are likely to receive an impermeable floor finish or be used for any purpose where the passage of water vapor through the floor is undesirable. Floor coverings such as linoleum, vinyl tile, carpeting, wood, and synthetic surfacing effectively seal the moisture within the slab where it eventually may loosen, buckle, or blister the floor covering. In order to lessen the moisture post -construction, we recommend using a low water -cement ratio concrete, less than .45. We recommend allowing the slab a 2-month drying period and testing the slab moisture condition before installing any floor covering. Wall Backfill Page 8