08-08-2007 Council Agenda - Laserfiche WebLink

Home Browse Search

These sheets present infoiuiation on preferred soil types, frost considerations, drainage, and lateral pressures. We recognize that basements are not planned for this building although the first data sheet also provides infornation on lateral earth pressures for design of exterior retaining walls. 4. Inspection and Testing The recommendations in this report are based on the subsurface conditions found at our test boring locations. Soil conditions can be expected to vary away from the soil boring locations, we recommend on -site observation by a Geotechnical Engineer or technician during construction to evaluate these potential changes. Soil density testing should be performed on new fill placed in order to document that the project specifications for compaction have been satisfied. 5. Final Site Topography Final soil surfaces should be graded to provide adequate drainage from structures and hard surfaces so that as little water as possible infiltrates into soils adjacent to the structures. The areas adjacent to footing walls should be adequately compacted, not loosely placed, to avoid this zone acting as a "sump" and creating nuisance conditions in the building area. 6. Pavement Subgrade Preparation and Pavement Design Design (1) With uncontrolled fill and Organic Sediments present on site the client can not expect a pavement section to be designed to last 20 years unless all unsuitable material is removed, see Table I, and replaced with engineered fill, oversized, compacted and tested. This can be expensive and the client may want alternative designs. MATERIAL Section Thickness Car Only Areas Section Thickness Heavy Duty Areas Bituminous Wear (Type 41) 1 ' %" 2 %z" Bituminous Base (Type 31) 1 '/z" 1 %z" Class 5 Aggregate Base (MnDOT 3138) 8" 8" MnDOT 3149.2B Select Granular Material to bottom of excavation to bottom of excavation Design (2) Typically the pavement section is concerned about the upper three feet of the parking lot or driveway's subgrade. The fill encountered in the proposed parking lot areas have N- values of 7 or greater in the upper three feet of the subgrade(not including Boring 6 which is in located near the proposed pond). The client may want to perform a test roll to evaluate the stability of the subgrade. We refer to the attached sheet entitled "Bituminous Pavement Subgrade Preparation and Design" for information on pavement design and subgrade preparation including items such as test roll evaluation, subgrade drainage and compaction recommendations. - 1 4 - 7