Investigation of Crack Behavior on Cover Soils at Landfill using X‐ray CT

Microstructure Investigation in Unsaturated Soils: A Review with Special Attention to Contribution of Mercury Intrusion Porosimetry and Environmental Scanning Electron Microscopy

“…However, much more powerful X-rays provided by synchrotron radiation and microfocus X-ray systems have recently allowed moving a step forward in the analysed domain and going to micrometric scale, narrowing the gap between meso and microstructural techniques , Takahashi et al 2006. Recent applications of these mesostructural techniques in unsaturated soils have been devoted to the monitoring of hydro-chemo-mechanical processes (Comina et al 2008), to the detection of desiccation cracks (Gebrenegus et al 2006;Mukunoki et al 2006), to the visualisation of diffusion/hydration phenomena and to the study of fluid movements (Rolland et al 2003;Rolland et al 2005;Van Geet et al 2005;Rodríguez-Rey et al 2006;Carminati et al 2006;Koliji et al 2006a).…”

Segmentation of X-ray tomography images of compacted soils

“…The basic principle and parameters associated with X-ray CT test were given by Kak and Slaney (1988), Herman (2009) and ASTM E1441-11 (2011). In geotechnical engineering, the X-ray CT studies were mainly focused on characterization of mineralogy (Van Geet et al 2000), characterization of failure in soils and failure process, crack and fracture studies in rocks (Otani et al 2000;Wang et al 2019), heterogeneity of soil structure and prediction of saturated hydraulic conductivity (Rogasik et al 1999;Elliot et al 2010;Pe ´riard et al 2016), quantification of macropores (Pierret et al 2002;Rab et al 2014), desiccation crack studies in landfill liners and cover soils (Gebrenegus et al 2006;Mukunoki et al 2006;Julina and Thyagaraj 2019;Tang et al 2019), fluid flow, diffusion studies and particle movement in soils (Nakashima 2000;Fukahori et al 2006;Sato et al 2006;Grayling et al 2018), internal structure of soils during hydration and water content distribution (Heijs et al 1995;Kozaki et al 2001;Van Geet et al 2005;Kawaragi et al 2009;Gens et al 2013;Saba et al 2014aSaba et al , 2014bGuerra et al 2018) and sand particle breakage, deformation and their microscopic structure (Ando `et al 2012;Alikarami et al 2015). The success of the X-ray CT tests largely depend on the thresholding technique adopted during the segmentation of the acquired CT images.…”

A subgrade cracking monitoring sensor based on optical fiber sensing technique

“…Although many cracks appear on the exposed surface of the soil specimens, there are others within the specimens . X‐ray, magnetic resonance, or electrical resistivity tomography, which may need expensive equipment or complicated setups, were used to detect the inner cracks of soil specimens . Levatti et al used ground‐penetrating radar (GPR) to monitor the cracking process inside soil specimens.…”