The stabilizer used in this study was
OPC only and partial replacement of OPC with
the RHA. DOH and JICA (1998) suggested a
reasonable OPC content for improvement of soft
Bangkok clay was within the range 80–200 kgm-3
of soil and a W/B ratio (the ratio of the weight of
water to the weight of OPC) of about 0.8–1.2. To
conform to these suggested specifications and
those of Nonthananandh et al. (2004), an OPC
content of 200 kg.m-3 of soil and a W/B ratio of 0.8
were adopted. In this study, SCM00 represented
the stabilized soil with OPC only (control) while
SCM10, SCM20, SCM30 and SCM40 represented
stabilized soil mixed with OPC and with partial
replacement of the OPC with RHA at 10, 20, 30
and 40% by dry weight, respectively.