Experimental Investigation of Mechanical Behavior of Plastic Concrete in Cutoff Walls

摘要

This paper presents the results of an extensive experimental study carried out to characterize the mechanical behavior of plastic concrete materials in consolidated undrained triaxial compression tests. The effect of various parameters such as confining pressure, mix design, age, and curing condition on the mechanical behavior including total and effective shear strength parameters, pore water pressure development, and the failure modes of the corresponding specimens was investigated. The geotechnical parameters of plastic concrete required for drained and undrained numerical analyses of embankment dams containing plastic concrete cutoff walls were presented as well. It was shown that the variation of confining pressure and plastic concrete mix design including cement and bentonite content and coarseness of aggregates obviously affects the contractive-dilative behavior and resultant excess pore pressure during undrained tests. The effects of specific curing condition of the plastic concrete samples under high water head as well as their failure mode at the completion of the tests were also investigated. The results revealed that the mode of failure varies from bulge-shaped sides to completely distinct shear bond in the various samples based on the mix design and confining pressure acting on the specimens.