I am working on a site where we are adding several feet of fill material. The underlying soils are saturated clayey sand soils (SC). The fill material is a slightly silty sand (-200=12 to 15%) with a modified proctor of 119 pcf and 11% moisture. We have two feet of fill in above the wet clayey soils (SC). The fill material was tested to be at 96 to 98% compaction of the modified proctor maximum dry density with an in-situ moisture of about 10%. However, poritons of the building pad were yielding and pumping under the weight of a human (i.e. me walking on the site). The fill was placed and compacted with a vibratory roller. I believe the vibratory roller caused the underlying satrurated clayey sand soils (SC) to lose shear strength. I believe the underlying clayeys soils will stabilize once the excess pore water pressures built up from the vibratory roller have had a chance to dissipate. The contractor has obviously passed the fill compaction requirement of 95% MPMDD, but the pumping subgradein the buidling pad is not acceptable. What to I need to do or what should I tell the contractor? Should they continue to place fill to see if they can bridge the underlying soft soils? Thanks for your help!
Red Flag Submitted
Thank you for helping keep Eng-Tips Forums free from inappropriate posts. The Eng-Tips staff will check this out and take appropriate action.
Reply To This Thread
Posting in the Eng-Tips forums is a member-only feature.
Improving the battery life of our devices remains one of the tech industryâ€™s biggest challenges, and the most inefficient draw on power comes from the display, more specifically, the backlight that illuminates most displays. Download Now