Experimental study on the seismic deformations of rockfill breakwaters

Breakwaters protect ports from high waves and hydraulic related phenomena. However, their seismic performance is of paramount importance in earthquake-prone areas. This study examined the seismic behavior and deformation of rockfill breakwaters with the use of shaking table modeling. As a part of performance base design, the scaled model tests were performed based on breakwaters of South Pars Petrochemical Port (SPPP), south Iran. The results indicate that, along with shear deformation, volumetric strain plays a major role in the deformation and settlement of breakwaters. Sections that were protected by armor exhibited better stability and performance. For SPPP breakwater a limited settlement was a strict performance criterion to allow installation of a pipeline on its crest. It was observed that densifying the upper part of breakwater did not control the settlement particularly when the core was made up of fine-grained material. The seismic performance of the pile-breakwater system also has been examined using scale-model tests. The results showed that the pile bearing system exhibited good performance in preventing the settlement of the pipelines running along the crest of the breakwater. However, it was shown that the pile bearing system did not provide sufficient control for lateral displacement and an isolation system would be necessary.