R2024-344 Resolution Accepting the Bid and Authorizing the Execution of a Contract with Burdick Plumbing and Heating Company, Inc. for the Vulcan Watermine Pipeline, City Project 2022-22

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PIPE FLOATING CONSIDERATIONS Pipe floating, as a result of high groundwater, is a consideration in areas of shallow fills. The design engineer should make every attempt to ensure an adequate amount of fill is placed above ' the pipe to prevent such floating. A rule of thumb to ensure an adequate amount of soil is above the pipe, is to place a volume of soil equal to one and one-half(1.5) times the volume of the pipe ' above the pipe itself. LATERAL EARTH PRESSURES Lateral earth pressures will be imposed on those jack pit walls and other such structural walls retaining fill materials or supporting structural backfill below grade. The net lateral pressure developing against these walls will depend upon the type of movement the wall can undergo, the backfill soil used, the wall height, and surcharge loading. ' - structural walls such as rigid cylindrical walls valve The lateral earth pressure on non yielding struc g y ' vaults), is the earth pressure at rest condition. This type of earth pressure may be estimated by assuming the wall pressure is equal to the pressure imposed by a fluid with a unit weight of 60.0 ' lbs. per cu. ft. This pressure is based on a coefficient of lateral earth pressure (at rest) equal to 0.5 for sand or gravel backfill. ' If low plasticity silty clays are used for backfill, this coefficient should be increased to 0.75 and the unit weight of the assumed fluid should be increased to 90.0 lbs. per cu. ft. In addition to the earth pressure, the expected water pressure should be added to compute the total lateral pressure. The lateral earth pressure for yielding structural walls, such as temporary sheet pile walls and walls restrained only at the bottom, is the active earth pressure condition. This type of earth pressure may be estimated by assuming wall pressure equal to the pressure imposed by a fluid with a unit weight of 40.0 lbs. per cu. ft. This pressure is based on a coefficient of active earth pressure equal to 0.33 for sand or gravel backfill. If the temporary sheet pile walls must stand for more than a few months, the fluid pressure should be increased to 60.0 lbs. per cu. ft. because the clayey soils will tend to creep, thus increasing the wall pressure. Geotechnical Exploration for Sanitary Pipeline New Vulcan Waterline Pipeline, Decatur, Macon County, Illinois SKS Project No. 12-418885 Page 6