Study on the Compaction Effect Factors of Lime-treated Loess Highway Embankments

This paper presents a study to investigate the effects of water content, lime content and compaction energy on thecompaction characteristics of lime-treated loess highway embankments. Laboratory compaction tests were conducted todetermine the maximum dry density pdmax and optimum water content wopt of loess with different lime Contents (0, 3, 5and 8%), and to examine the effects of water content, lime content and compaction energy on the value of pdmax and wopt.In situ compaction tests were performed to obtain the in situ dry density and the degree of compaction k ofdifferent lime-treated loess. Experimental embankments with different fill materials (0, 3, 5 and 8% lime treated loess)were compacted by different rollers during in situ tests. The results indicate that pd increases due to the increase of watercontent w . Once water content exceeds wopt, dry density pd decreases dramatically. The addition of lime induced theincrease of wopt and the decrease of pdmax. A higher compaction energy results in a higher value of pdmax and a lowervalue of wopt. The value of pin-situ achieves it’s maximum value when in situ water content win−situ was larger than thevalue of wopt (+1-2%). The degree of compaction k can hardly be achieved to 100% in the field construction ofembankments. Higher water content and compaction energy is needed for optimum compaction.

Keywords:

Lime-treated Loess , Highway Embankments , Loess Compaction , Degree of Compaction