| In China, the wide distribution of loess,genetic type,thickness variation,collapsible andcomplex compression. In the loess region by the geographical conditions commonly usedlime to improve the loess as roadbed filler. Mixed with lime can effectively improve thephysical and mechanical properties of the loess, and will continue to improve with the growthof the age. However, in practical engineering design, designers rarely consider the lime soilengineering properties of the curing period. This will make the design value is low in actualvalue, resulting in economic waste.Conducted a laboratory test of lime to improve the loess, including moisture content,density, heavy compaction test limits of moisture content test, consolidation test, triaxial tests,lime to improve soil physical and mechanical properties changes of these trials,analysis of therelationship between project performance and curing period. This experiment, the limecontent of1%,3%,6%,10%,12%, the curing period for the7d,14d,28d,60d,90d,180d. Byboundaries of moisture content we can know the loess is silty clay; Heavy Compaction Test todetermine the optimum moisture content and maximum dry density of a variety of dosage oflime to improve the loess;With the growth of the curing period, lime soil shear andcompression continued to improve. The shear strength index increases, the compressionmodulus increases, the compression factor decreases。Specimen destruction gradually becomebrittle failure by plastic collapse. In the semi-logarithmic coordinates shear strength and agehad a linear relationship. The lime reinforcement loess subgrade design parameters choicecome to the conclusion is: when the Lime dose is low (≤6%)，subgrade design parameters ofthe curing period of not less than28days, the larger dose (>6%) design parameters of thecuring period not less than60d. Take full advantage of the limestone soil of this nature to savematerials, reduce the project cost of great significance. |
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