Characteristics of Cement Treated Soil: A Case Study from Soft Bangkok Clay and Red Soil of Nepal

Abstract

Soft Bangkok Clay from Thailand and clayey silt of red soil,
Nepal have been incorporated for the research as a case study
in order to understand the characteristics. Highly plastic soft
Bangkok Clay and low plastic clayey silt have been confirmed
as non-swelling soils through XRD analyses. The peak
intensities of red soil from Nepal is more than two times higher
than the intensity of soft Bangkok Clay. Higher water content
and warm temperature form lower intensities in the soft Bangkok
Clay resembling the amorphous state with compared to red soil
of Nepal. As a result, the amount of admixture of cement in clay
varies significantly to enhance the adequate strength. Hence,
the research has delineated through determining undrained
strengths treated with cement in different proportions at different
curing time and checked the stiffness by passing through
ultrasonic wave velocity. The specimens were extracted from
the depths of 3.0 m and 12.0 m soil-cement column formed by
dry method in Thailand and in-situ clayey silt from Nepal was
treated with cement. Besides, 20% local poorly graded soil was
added in the clayey silt and all treated specimens were cured for
7, 14 and 28 days. The results confirmed that the Bangkok Clay
received the highest strength at 13.89% of cement addition for
3.0 m depth core and 11.11% of cement treatment received the
maximum strength for 12.0 m core cured for 28 days.
Conversely, clayey silt from Nepal received the maximum
strengths at 7% cement treatment cured for 28 days.