PL PACKET 08172021 - Laserfiche WebLink

Home Browse Search

Bremer Financial Corporation Project B2008939 November 17, 2020 Page 8 B.4. Laboratory Test Results The Log of Boring sheets in the Appendix show the results of soil laboratory testing we performed, next to the tested sample depth. The moisture content (ASTM D 2216) of the selected samples varied from approximately 4 to 17 percent, indicating that the material was likely near or below its probable optimum moisture content. The organic content tests (ASTM D2974) of the selected organic samples were approximately 2 to 3 percent organic, indicating the selected samples are slightly organic. C. Recommendations C.1. Design and Construction Discussion C.1.a. Building Subgrade Preparation We believe there are multiple viable subgrade preparation procedures for this site. Two of the most likely are summarized below. C.1.a.1. Option A – Standard Soil Correction Based on the results of our subsurface exploration and evaluation, spread footing foundations bearing on the native soils or engineered fill can support the proposed structure, after performing subgrade preparation. Subgrade preparation includes removing existing fill, topsoil or organic soils, structures and any very loose sands or soft clays directly below the footings. If the soil corrections are needed and extend more than 10 feet from finished grade, select sand with less than 12 percent fines should be placed if more than 10 feet below finished grade. C.1.a.2. Option B – Ground Improvement Based on the excavation depths required for a soil correction , and the costs associated with it, we believe that ground improvement such as aggregate piers/stone columns may be another viable option for subgrade preparation that may be more cost effective than a standard soil correction. If the owner can assume some risks of future slab settlement, ground improvement would not be needed below slabs,