Study on Variation Rule of Pore Pressure on CPTU Model Test

Abstract:

Through a series of Piezocone Penetration Test (CPTU) model tests with saturated clay soil, excess pore pressure produced by CPTU penetrating and dissipating has been measured by CPTU probe and pore pressure mini-transducers, the variation rules of excess pore pressure has been analyzed, the results show that at the same transducers layer, the value of initial excess pore pressure at the probe is biggest, and with the horizontal distance from probe increasing, the value of initial excess pore pressure measured by transducers around the probe has been decreased quickly; at the same dissipating process, the value of initial excess pore pressure measured by transducers locating in the same horizontal plane with probe is bigger than the value by transducers of the other layer; difference between the variation rule of excess pore pressure dissipation measured by CPTU probe and pore pressure mini-transducers is that after the value of excess pore pressure is maximum, with the dissipating time increasing, the value of excess pore pressure measured by probe decreased rapidly, but at first the value of excess pore pressure measured by transducers decreased slowly and then after a short time decreased rapidly; the time of 90% of the maximum of excess pore pressure dissipating measured by CPTU probe is longer than the time of 90% of the maximum of excess pore pressure dissipating measured by transducers; at the same transducers layer, with horizontal distance from the probe increasing, the time of 90% of the maximum of excess pore pressure dissipating decreased. The achieved result can provide a foundation for further study for CPTU mechanism.

• Periodical: Advanced Materials Research (Volumes 160-162)
• Pages: 544-549
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.160-162.544
• Online since: November 2010
• Authors: Yan Chun Tang, Gao Tou Meng
• Keywords: CPTU, Dissipating, Excess Pore Pressure, Model Test, Pore Pressure Mini-Transducer

References

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