Seismic behaviours of rubberized concrete (RuC) columns : bidirectional shaking table test

Abstract

Rubberized concrete (RuC) is an environmentally friendly material, showing many merits in the field of civil and earthquake engineering. While extensive research has been done on the static and dynamic properties of RuC materials and performance of RuC structures, shaking table tests on the seismic performances of RuC structures remain limited. Based on the best knowledge of the authors through comprehensive literature searches, this paper presents the first bidirectional shaking table test to investigate the seismic behaviours of RuC columns with different rubber volume fractions (R<inf>v</inf>) subjected to ground excitations of different peak ground accelerations (PGAs). Results showed the RuC columns were generally more ductile, deformable and energy-dissipative than the conventional concrete column, while the loading-capacity could be significantly reduced when using an excessive rubber replacement. Notably, the column with 10 % rubber replacement, i.e., 10 % RuC column exhibited up to a 9.72 % increase in lateral drift capacity and a 73.33 % reduction in residual displacement compared to the conventional column. The 10 % RuC column in average reduced the peak acceleration response by 32.05 %. Importantly, the bidirectional earthquake ground motion induced complex seismic responses, highlighting the necessity of incorporating these effects in the seismic design and analysis.