Loizos Pelecanos

Distributed fiber optic sensing of axially loaded bored piles

AbstractInstrumented pile tests are vital to establish the performance of a pile and validate the assumptions made during initial design. Conventional instrumentation includes vibrating wire strain...

The Effects of Dam–Reservoir Interaction on the Nonlinear Seismic Response of Earth Dams

ABSTRACT The objective of this study is to investigate the effects of dam–reservoir interaction (DRI) on the nonlinear seismic response of earth dams. Although DRI effects have for long been considered as insignificant for earth dams, that conclusion was mainly based on linear elastic investigations which focused only on the acceleration response of the crest without examining the seismic shear stresses and strains within the dam body. The present study explores further the impact of DRI focusing on the nonlinear behavior of earth dams. The effects of reservoir hydrodynamic pressures are investigated in terms of both seismic dam accelerations and nonlinear dynamic soil behavior (seismic shear stresses and strains). It is shown that although dam crest accelerations are indeed insensitive to DRI, the stress and strain development within the dam body can be significantly underestimated if DRI is ignored.

Steady-state and transient dynamic visco-elastic response of concrete and earth dams due to dam-reservoir interaction

The aim of this study is to investigate the effects of dam–reservoir interaction on the dynamic response of dams. Both thin rectangular concrete cantilever and large trapezoidal earth dams are considered with empty and full reservoir. It has recently been shown by Pelecanos et al. [32] that the amplification of accelerations at the crest of the dam depends on the combinations of the frequency of the harmonic acceleration load and the fundamental frequencies of the dam and the reservoir. This study considers transient dynamic loading and selected scenarios of different combinations of the abovementioned frequencies are examined under random seismic acceleration load. It is shown that for certain cases the amplification of accelerations of the dam can be affected by the presence of the upstream reservoir. In general, thin rectangular concrete cantilever dams are found to be considerably more sensitive to dam–reservoir interaction than large trapezoidal earth dams. Therefore, this investigation examines the significance of dam–reservoir interaction and when this interaction should be taken into consideration or it could be neglected.