English abstract
Dune sands belong to the category of problematic soils because of its low strength
characteristics, susceptibility to collapse on wetting, low bearing capacity, high
permeability, and precludes the support of structures loads and road building.
Consequently, it is necessary to stabilize dune sands to take advantage of the vast areas
and establish infrastructure. Moreover, roughly no studies were found worldwide for
adopting Deep Soil Mixing technology (DSM) in stabilizing dune sand.
This research experiment evaluates the deep soil mixing technique's effectiveness in
stabilizing dune sand by developing a laboratory scaled apparatus and investigating
particular parameters that influence strength characteristics. Also, an attempt to
explore potential stabilize agents as a grout material in DSM such as Cement Kiln Dust
(CKD), Nano-Silica and Polymer
Eight parameters are studied to evaluate the DSM method on Dune sand: (1)
Water/Binder; (2) Replacement of CKD; (3) Replacement of Nano; (4) Replacement
of Polymer; (5) Auger speed; (6) Penetration speed; (7) Auger angle; (8) Cement
Content. The selected parameters will be measured by undertaking Unconfined
Compressive Strength (UCS) tests at specimens ages of 7, 14, and 28 days.
The results reveal that binder content, auger speed, and penetration speed significantly
affected increasing UCS. The blade with 40-degree had a better performance than with
20-degree. In comparison to pure OPC binder, all the binders' combinations of OPC
with a replacement of (CKD, Nano-silica, and polymer) are considered an effective
sample and can be used in DSM. Lastly, by graphical analysis of the results, functional
equations were derived from the results for the UCS of 28-days, the strength for a
specific binder dosage, and the secant modulus with acceptable precision, which may
be used for prediction of DSM performance in dune sand.
