Effect of soaking on the CBR-value of subbase soil

Abstract EN

The effect of soaking on the top and bottom CBR value of a sub-base is studied in this paper.

Fourteen CBR samples were prepared at 95 % relative modified AASHTO compaction .Two CBR samples were prepared for each soaking period of 0.

4, 7, 14, 30 and 60 days.

These samples were prepared and compacted mechanically in the laboratory.

The first group was tested in case of unsoaked while the second group was tested in case of soaking.

The results showed that, a significant drop in the CBR for top and bottom due to the soaking was observed compared with natural case due to softening of soil particles Which means that the bearing capacity of sub base soil decrease with increase of soaking time.

Most of decrease in soaked CBR value is pronounced in the first days for top and bottom CBR, respectively.

And it dropped to 20 % and23 % value for top and bottom after 60 days soaking period and this drop is in full of weakness of soil with soaking.