Laserfiche WebLink
<br />I <br /> <br />City of Elk River <br />Project BN-04-06875 <br />December 8, 2004 <br />Page 6 <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />D.3. Observations <br />We recommend a geotechnical engineer observe all excavation and pavement subgrades. These <br />observations are recommended to evaluate if the sub grade soils are similar to those encountered <br />by the borings and adequate to support the proposed construction. <br /> <br />I <br />I <br /> <br />D.4. BacklIlls and Fills <br />Site soils, which will be excavated and reused as backfills and fills, appear to be dry of optimum. <br />We anticipate it will be necessary to moisten these soils to achieve the recommended <br />compaction. We recommend that backfills and fills be placed in lifts not exceeding 4to 12 <br />inches, depending upon the size of the compactor and material usecl <br /> <br />I <br /> <br />I <br /> <br />D.S. Testing <br />We recommend density testing be performed beneath pavements. We also recommend density <br />testing of the compacted pavement subgrade and gravel base course. Samples of proposed <br />backfill and fill materials should be submitted to our testing laboratory at least three days prior to <br />placement for evaluation of their suitability and determination of their optimum moisture <br />. contents and maximum dry densities. <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />We recommend at least one density test be performed on the subgrade for every 10,000 square <br />feet of pavement area, with at least one test for every 2 vertical feet of embanlanent placed. We <br />recommend the gravel base and bituminous surfacing be tested at a similar frequency. <br /> <br />I <br />I <br />I <br /> <br />D.6. Cold Weather <br />If site grading is anticipated during cold weather, we recommend good winter construction <br />practices be observed. All snow and ice should be removed from cut and fill areas prior to <br />grading; <br /> <br />Roadbed embanlanents should not be constructed during peliods when the embanlanent material <br />freezes while being placed and compacted, nor should any embanlanent material be placed on <br />soil that is frozen to a depth greater than 4 inches. When the foundation soils are frozen to a <br />depth exceeding 4 inches, at a time when weather conditions are such that embanlanent <br />construction could be continued without the material freezing as it is being placed and <br />compacted, the contractor may be permitted to excavate the frozen foundation soil and proceed <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />I <br />I <br />