บดินทร์ แต่งเจริญสุข. Behaviors of Cement-Treated Laterite with Industrial Ash Replacement for Construction ofRoad Structure. Master's Degree(Civil Engineering). King Mongkut's University of Technology Thonburi. KMUTT Library. : King Mongkut's University of Technology Thonburi, 2010.
Behaviors of Cement-Treated Laterite with Industrial Ash Replacement for Construction ofRoad Structure
Abstract:
This research presents a study on strength and deformation characteristics of cement
mixed laterite with partial cement replacement by fly ash and rice husk ash. Special
attention was paid to the investigation of stiffness of the mixtures under cyclic loading,
or the equivalent modulus. The experimental study was done by performing a series of
unconventional unconfined compression and cyclic loading tests. All strain values were
locally measured by means of a pair of local deformation transducers (LDTs). From
tested results, unconfined compressive strength of the mixtures having small cement
content (1% for fly ash and 1-2% for rice husk ash replacement) with ash replacement
of 10-30%, is close to that of the mixtures without ash replacement. For mixtures with
higher cement content (2% or 3%), replacing the cement with ashes of 10-30% results
in decrease of value of unconfined compressive strength. The efficiency of fly ash and
rice husk ash on Portland cement replacement partially in laterite soil cement was
discussed. The equivalent modulus values (Eeq) from cyclic loading test were evaluated
by performing monotonic loading to considered level stress and sustained loading then
applied minute-amplitude cycles of unload and reload. The cyclic loading test results
indicate that equivalent values did not decrease with varying fly ash and rice husk ash
proportion for cement replacement, except for 30% of fly ash replacement. An empirical
equation relating the efficiency factor (k) and mixing proportion proposed a good
prediction for ultimate strength and equivalent modulus values.