Seismic performance of a pre-cast concrete arch system

Lock Block Ltd of Vancouver, Canada produces pre-cast concrete products, including their name-sake retaining wall system which uses recycled materials. More recently they have adapted these products to create a system of easy to assemble dome and arch structures. This study aims to evaluate the behavior of these systems when subjected to seismic loading. A program of experimental shake-table testing was undertaken using a small scale arch models. For the tests, a suite of six earthquake records were chosen, including Tohoku 2011, Loma Prieta 1989 and Kobe 1995. The records were time scaled to increase the applied frequencies to the tested models; the accelerations were applied full-scale. For each model, they were tested with increasing intensity until failure occurred; this determined the failure level for each earthquake. For all the cases, the failure mode exhibited the typical four-hinge mechanism. The failure intensity varied with type of earthquake, with impulses being the dominant factor. The study also explored a method of reinforcing the arches, using a steel band over the structure to withstand the tension force, anchored at both ends of the arch. This method performed well to all applied earthquakes.