Investigation of Excess Pore Water Pressure in Cone Penetration Test in Saturated Clayey Soils under Undrained Condition

The widespread use of the cone penetration test in geotechnical engineering, due to its quick identification of soil layers and properties, has led to the development of various analytical methods for interpreting this test. Monitoring excess pore water pressure during the piezocone penetration test can be crucial for assessing the properties and engineering parameters of clayey soils. The initial stresses in the ground and the coefficient of lateral earth pressure at rest, K0, are important parameters needed for the design and analysis of various geotechnical problems such as piles, and slope stabilities. Due to the limited research on clayey soils, the significance of understanding their behavior, and the limitations of laboratory experiments, this study investigates soil behavior via numerical modeling of cone penetration tests in saturated clay with undrained conditions. In this study, the effect of the coefficient of lateral earth pressure and initial effective vertical stresses on pore water pressure has been investigated. Additionally, the correlations between excess pore water pressures at points u2 and u1, as well as u2 and u3, have been outlined. Modified Cam-Clay constitutive model was employed in all numerical analyses using FLAC2D software. The validation of proposed relationships was also addressed using the database of field tests available in the literature provided by different researchers. The obtained results indicated that as each parameter of lateral pressure coefficient and vertical effective stress increased, the excess pore water pressure also increased at all three locations where pore water pressure is measured.