Soil mixing design methods and construction techniques for use in high organic soils.
-
2015-06-01
-
Details:
-
Creators:
-
Corporate Creators:
-
Subject/TRT Terms:
-
Publication/ Report Number:
-
Resource Type:
-
Geographical Coverage:
-
Corporate Publisher:
-
Abstract:Organic soils present a difficult challenge for roadway designers and construction due to the high
compressibility of the soil structure and the often associated high water table and moisture content. For
other soft or loose inorganic soils, stabilization via cement or similar binders (a method called soil
mixing) has proven to be an effective and predictable solutions; the FHWA has published a
comprehensive design manual for these techniques. Organic soils, however, are not addressed therein
to a level of confidence for design as organic soils do not follow the trends of inorganic soils.
In short, the high porosity, high water content, and high levels of humic acids differentiate organic soils
from all other soils where soil mixing has been proven successful. To combat these effects, more
cement content is required to bring the water/cement ratio down to acceptable levels and even more
cement is required to offset the acidity.
Extending the observations of past researchers, a threshold cement content was defined below which
no strength gain was achieved. This threshold was then defined as a cement content offset above which
the measured strengths matched well with other soil types.
This report presents the findings from a thorough literature search, laboratory bench tests, large scale
laboratory tests, field evaluation of past and on-going projects and concludes with recommendations
for designing for soil mixing applications in highly organic soils.
-
Format:
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type: