RECYCLE TIRE ISOLATOR AS EARTHQUAKE RESISTANCE SYSTEM FOR LOW RISE BUILDINGS

Abstract

The purpose of this research is to study the use of Recycle Tire Isolator (RTI) as earthquake resistance system to protect low rise buildings from life threatening collapses and casualties when earthquake takes place. Many buildings are built with seismic design based on the concept of increasing the resistance capacity of the structures by using shear walls, braced frames and others. However, these methods result in high floor accelerations and could cause significant damage to nonstructural components of the buildings. Some of these buildings’ content are quite costly. Hospitals and government offices, for example, are important premises which contain valuable machines or documents such as X-rays machines and the data stored in computers. RTI could be installed at the pad foundation to absorb low to moderate earthquake energy which is less than 6 Richter scale. The isolator uses recycle tire as main component to absorb lateral forces produced during earthquake. The use of RTI also helps to reduce the hazard of dumping old tires on earth. This study focuses on the role of RTI in protecting two stories buildings. The displacement of RTI was measured when vertical or lateral forces were applied. Compression test using Universal Testing Machine was carried out in the laboratory to find the maximum vertical load. The vertical load was applied to the specimen by the vertical hydraulic actuator in displacement control. The specimen was monotonically loaded to failure. COMSOL Multiphysic V4.2, a finite element software was used to model the behavior of RTI and the results were compared to the results obtained from laboratory. The behavior of RTI was also compared to the behavior of existing rubber bearing (RB) and scrap tire pads (STP). The results of laboratory and finite element analysis indicated that RTI could support a maximum axial load of 184 kN and lateral force up to 20 kN. Based on the results, RTI had a potential to be used as a device to protect low rise buildings against low to medium earthquake. The compressive strength of RTI and STP was quite similar with about 6.7% difference. This was expected since both materials were recycle tires. The compression modulus between RB and RTI was also similar with about 11.1% difference. This showed that RTI had similar features with RB and STP. However, RTI fabricated mainly by using recycle tires contained about 4 to 6 layers of steel mesh which was stiffer than RB and more efficient in supporting heavier structures vertically. The use of recycle tires in production of RTI made it more affordable for most house owners compared to RB or STP.