Seismic performance on tuned liquid damper in novel wall interlocking block

Abstract

Building structural vibrations are generally regarded to be a serviceability problem, mainly affecting the architectural façade, and occupant comfort. However, in extreme cases such as earthquakes, it may lead to structural collapse. The excessive building vibrations are sometimes seen due to the resonant effect. In this study, the following blocks were proposed and investigated: Tuned Liquid Damper block (i-Block), Friction Damper block (B-Block) and vertical supporting block (V-Block). The newly developed non-loadbearing cement interlocking-block masonry was incorporated with damping characteristics. The laboratory study has identified Young’s modulus of 3.3 N/m2 and Poisson’s ratio of 0.278 to be most optimum for dry-mix concrete. Meanwhile, based on various robustness tests, the i-Block was found to possess the most suitable mechanical properties for interlocking block damper. Geometrical aspects of the i-Block were fixed at internal dimensions of 190 mm (length) x 60 mm (width) x 90 mm (height) with varying water depth, dw in the range of 0 mm to 80 mm. In the dynamics tests, resonant Transmissibility’s ratio plot approaches were used to compare the control sample with different dw. The responses of sine-sweep resonant test have shown the increasing damping values which were compared by simulation and empirical calculation. It was found that natural frequencies, fn obtained from the test were considerably matching the numerical simulation and empirical calculation. Interestingly, a small portion of water at 5 mm dw was sufficient to increase the damping ratio of the overall performances. In the seismic simulation, the Northridge, El Centro and Loma Prieta ground motion were numerically simulated by Ansys software. The peak ground base shears to displacement hysteresis on structural responses have been reduced by 19%, 26% and 35% for Northridge, El Centro and Loma Prieta’s earthquakes respectively. Meanwhile, effective performances were observed at the top floor level in relation to the mass of lower water contents to overall structure mass ratio requirement. Therefore, i-Block can be used to provide damping and reduce responses to building from earthquake disasters.