Abstract
The effect of variable confining pressure (VCP) on the cyclic deformation and cyclic pore water pressure in K0-consolidated saturated soft marine clay were investigated with the help of the cyclic stress-controlled advanced dynamic triaxial test in undrained condition. The testing program encompassed three cyclic deviator stress ratios, CSR=0.189, 0.284 and 0.379 and three stress path inclinations ηampl=3,1 and 0.64. All tests with constant confining pressure (CCP) and variable confining pressure (VCP) have identical initial stress and average stress. The results were analyzed in terms of the accumulative normalized excess pore water pressure rqu recorded at the end of each stress cycle and permanent axial strain, as well as resilient modulus. Limited data suggest that these behavior are significantly affected by both of the VCP and CSR. For a given value of VCP, both of the pore water pressure rqu and permanent axial strains are consistently increase with the increasing values of CSR. However, for a given value of CSR, the extent of the influence of VCP and the trend is substantially depend on the CSR.
Highlights
Engineering structures founded on soft marine clay deposits are often designed to withstand cyclic loading such as earthquakes, traffic, or ocean waves etc. during their operational life
As most of the variable confining pressure (VCP) studies were conducted on granular materials or sandy soils in free to drained conditions, the pore water pressure during cyclic loading is not considered
Reliable excess pore-water pressure in the specimen during cyclic loading is the key to assessment of effective stresses that control its deformation response
Summary
Engineering structures founded on soft marine clay deposits are often designed to withstand cyclic loading such as earthquakes, traffic, or ocean waves etc. during their operational life. Cai et al (2013) conducted a series of undrained and partially drained one-way cyclic triaxial tests on remolded saturated clay under various VCP and CCP stress paths with identical initial stress (p0, q0) to simulate traffic loading and observed that the cyclic confining pressure has great influences on the characteristics of pore water pressure and axial strain under both undrained and partially-drained conditions [20]. The literature listed above revealed that, no consensus has been reached on the coupling effect of cyclic deviator stress and cyclic confining pressure on the cyclic behavior of soils, apart from the cyclic stress amplitude and the number of cycles, the cyclic deformation and cyclic pore water pressure in clays are significantly affected by the type of VCP tests and drained conditions. Knowing the extent of the effect and the trend is important in the evaluation of the dynamic properties of soil for the analyses of cyclic response of soil deposits
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
