|
Soil Cement
Water Resources Home
> Soil Cement
Soil Cement for Water Resources
 The
U.S. Bureau of Reclamation undertook a field research project in
1950 to determine if soil-cement was a durable material when exposed
to severe climatic conditions and loading conditions imposed by
pounding waves. The Bureau constructed a stair stepped soil-cement
slope facing along a portion of the Bonny Dam reservoir located
in far eastern, Colorado. The soil-cement was inspected over a ten
year period which saw an average of over 100 freeze cycles a year
with waves exceeding eight feet in height. The unqualified success
of this research kicked off the increasing use of soil-cement in
water resources applications.
Soil-cement is now readily used not only for embankment
slope protection but also for stream bank protection, grade control
structures, and reservoir and channel linings. Soil-cement is defined
in ACI 116R as a mixture of soil and measured amounts of portland
cement and water compacted to a high density.  It
can be further defined as a material produced by blending, compacting,
and curing a mixture of soil/aggregate, portland cement, possibly
admixtures including pozzolans, and water to form a hardened material
with specific engineering properties.
Almost any inorganic type soil is suitable for soil-cement. The
fines content (minus No. 200 sieve material) typically ranges from
5 % to 35 %. Typically granular soils are preferred over clay soils
because they pulverize more easily and require less cement to achieve
the required strength and durability. A well graded  granular
soil will generally require 5 % to 8 % cement by dry weight of soil
aggregate, while a soil that is a sandy silt with 25 % passing the
No. 200 sieve will need 8 % to 11 % cement. The typical construction
of soil-cement water structures is shown in the photo series.
Development of Soil-Cement for Water Resources
A rapid expansion of water resources projects in the Great Plains
region of the United States followed World War II. Rock riprap of
satisfactory quality for upstream slope
protection was not locally available for many of these projects,
and the high costs of transporting the material from distant quarries
made the economic feasibility of some projects questionable.  The
U.S. Bureau of Reclamation (USBR) initiated a major research effort
to study the suitability of soil-cement as an alternative to riprap.
Following successful laboratory studies that showed soil-cement
made of sandy soils were durable in a water erosive environment,
the USBR constructed a full-scale test section in 1951.  A
location along the south-east shore line of Bonny Reservoir in eastern
Colorado was selected because of natural severe service conditions
created by large waves, ice, and more than 100 freeze-thaw cycles
per year. The USBR was convinced after evaluating the test section
for ten years that soil-cement was suitable for slope protection.
Two significant flood events occurred in Arizona in
1983 and 1993 causing millions of dollars in damage. The areas protected
with soil-cement had excellent performance. Photos show the flooding
along the Santa Cruz River in Tucson.
|
 |
More on Soil Cement:
Overview
Embankment Slope Protection
Bank Protection/Levees
Drop and Grade Control Structures
Liners
FAQs
Southern California Case Study
Moss Creek Dam Case Study
Rueter-Hess
Dam and Reservoir Case Study
RCC Contractor Directory
|