Laserfiche WebLink
Bremer Financial Corporation <br />Project B2008939 <br />November 17, 2020 <br />Page 11 <br /> <br /> <br />C.2.b. Excavation Oversizing <br />When removing unsuitable materials below structures, we recommend the excavation extend outward <br />and downward at a slope of 1H:1V (horizontal:vertical) or flatter. See Figure 2 for an illustration of <br />excavation oversizing. <br /> <br />Figure 2. Generalized Illustration of Oversizing <br /> <br /> <br /> <br />C.2.c. Excavated Slopes <br />Based on the borings, we anticipate on-site soils in excavations will consist of silty sand and clayey soils. <br />These soils are typically considered Type B Soil under OSHA (Occupational Safety and Health <br />Administration) guidelines. OSHA guidelines indicate unsupported excavations in Type B soils should have <br />a gradient no steeper than 1H:1V. Slopes constructed in this manner may still exhibit surface sloughing. <br />OSHA requires an engineer to evaluate slopes or excavations over 20 feet in depth. <br />1. Engineered fill as defined in C.2.g <br />2. Excavation oversizing minimum of 1 to 1 <br />(horizontal to vertical) slope or flatter <br />3. Engineered fill as required to meet <br />pavement support or landscaping <br />requirements as defined in C.2.g <br />4. Backslope to OSHA requirements