Laboratory Study on the Cyclic and Postcyclic Behavior of Plastic Concrete Used in Cutoff Walls of Embankment Dams

摘要

In this paper, the cyclic response of plastic concrete material used in cutoff walls of embankment dams has been studied. To investigate the dynamic behavior of such a material, an extensive series of triaxial monotonic and cyclic compression tests were performed on plastic concrete specimens. The effects of confining pressure, mix design, age, anisotropy, and various loading conditions on the cyclic behavior of the material as well as the variation of the shear modulus and damping ratio have been assessed. Moreover, an empirical equation was derived by which the maximum shear modulus of the plastic concrete material can be estimated based on the stress level. Furthermore, to evaluate the degradation of the material due to cyclic loadings, the postcyclic monotonic stress-strain curves were compared with the corresponding curves for the specimens not subjected to cyclic loadings. It was concluded that in the high-cement- or low-bentonite-content specimens especially at the higher ages, the cyclic loading has little effect on the postcyclic monotonic behavior of the material.