Seismic behaviour of roller compacted concrete dams under different base treatments

Abstract

The effect of base roughness on the seismic behaviour of roller compacted concrete gravity dams were investigated by pseudo-dynamically testing two 1/75 scaled specimens with smooth and rough base treatments. Both specimens were tested under the effect of three different hazard level earthquakes and also a pushover experiment was conducted to obtain the capacity curve of each specimen. The smooth base specimen exhibited significant sliding under the effect of the maximum credible earthquake motion. In contrast, the rough base specimen had no base sliding response even during the pushover experiment, whereas large body cracks reaching almost the downstream toe of the specimen was the main reason for the loss of lateral strength. The numerical simulation of these two experiments were also conducted by using the sliding response analysis and the finite element method. The base sliding response of the smooth-base specimen was simulated successfully by considering a variable friction coefficient. The finite element results for the rough-base specimen was also promising as far as the base shear and tip displacement estimations were considered. However, the crack propagation estimates were inconclusive due to the severe diffusion of the cracks.

Keywords:

• RCC gravity dams
• body failure
• base sliding
• pseudo-dynamic testing
• numerical simulations

Acknowledgements

The contributions of Salim Azak and Hasan Metin during the laboratory work are also gratefully acknowledged.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported by the Turkish National Sciences Foundation TUBITAK under the grant number 111M712.