Goal of Compaction - University of Waterloo

1 1 CompactionAsphalt, Roads, Trench Restoration2 Goal of Compaction Place loose soil in the field and compact it to make soil strong as possible Maximum shear strength Very little settlement Find soil lowest dry unit weight3 Field Compaction EquipmentVibratory Smooth Wheel Rollers45 Field Compaction EquipmentPneumatic rubber-tired rollerField Compaction EquipmentVibratory sheepsfoot roller6 Soil Compaction Equipment7 Field Compaction Equipment Vibroflotation unit Vibrate loose sand depositsField Compaction Equipment Drop weight 10 to 20 feet at close centres Makes craters Loss fill and sand8 Field Compaction EquipmentProctor Test9 Standard proctor TestModified proctor Test1011 Impact of No. BlowsImpact of No. Blows12 Impact of proctor Method Increase energy increase dry unit weight Decrease optimum moisture content 2004 Brooks/Cole Publishing / Thomson Learning Influence of Compaction on soil hydraulic conductivity13 Soil Compaction MeasurementSoil Compaction Measurement Use dry sand with known dry density and specific gravity Use dry sand to get volume of hole Quick and reliable method14 Soil Compaction Measurement Use radioactive material to get moisture content and soil density Quick method Reliable if calibrated Radioactive device therefore special transportation and rules must be followedCompaction SpecificationStandard proctor Specification 95 to 100 percent of MDUWM odified proctor Specification 92 to 98 percent of MDUW100 ( proctor )t unit weighdry weighdry Insitu (%)

2 Level Compaction x=15 Compaction Specification Make sure compacted soil same as proctor material (grain size distribution analysis) Add water to soil if too dry95% Field Specification