Characterizing the Effects of Pore Pressure Reduction and Voids using X-ray CT Scan towards Physical Changes due to Static Loading

Abstract

Peat soil is widely known as soil with very low compressive strength and poor in shear strength. When loaded, it is easy to deform and visually witnessed. To understand the vital means to study the characteristic of this rupture soil material, which is of great significance in determination of soil shear strength involving peat soil settlement where pore and voids diminished when loaded especially for embankment prediction. On this basis, static triaxial test has been carried out to simulate the loading phase while pore and void elements inspected through 2D X-ray CT scan. Through the process, peat and the relationship between loading, pore and physical changes are monitored. Measurements were performed on consolidated undrained condition with strain-controlled method under monotonic loading. The 2D X-ray CT scan pattern of the sample deformation was imaged before and after loading process. Sample height is 100 mm and diameter 50 mm in cylindrical shape. Physical changes are visualized, and the data showed that, pore and voids diminished by loading factor, leading pore pressure decrease with increase of effective pressure. Pore pressure developed down-trend characteristic. From the result, there is no volume change are disclosed when loaded. From 2D CT-scan shows that, the pore between peat particles diminished in volume after static loading and parallel to static loading process.