Edinburgh Napier University

  The main aim of the project seeks to enhance the resistance of the soil foundation against seismic events with the introduction of a mixture composed of recycled rubber tyres and sand particles. As a consequence of the regulation, the reuse and recycling of tyres has been proposed during the past decades for different purposes such as civil engineering projects, converted into ground rubber applications or some agricultural uses. The implementation of tyres in civil engineering projects has been mainly focused on its use during the past thirty years as backfill for retaining walls and bridge abutments, additive to asphalt, sound barrier and admixture in bituminous concrete. However, some of the most recent results have demonstrated that rubber-soil mixture is a highly deformable material which is able to dissipate a great amount of energy compared to the sand alone. Therefore, this property confers rubber-soil mixture an ideal material to be used as a seismic isolator.

It has been estimated that the annual losses caused by seismic events in the U.S. are around £4 billion. Moreover, it has been registered that over 813,000 casualties related to the action of earthquakes have occurred principally, among other causes, due to the collapse of residential building since 2000. Actually, various traditional seismic isolation systems have been successfully introduced in a few government buildings and civil structures such as schools and hospitals. However, these systems are relatively expensive apart from the fact that it presents some technical difficulties that restricts its introduction to uniquely new buildings. Hence, the investigation with rubber-soil mixtures is encouraged by the numerous benefits that the implementation of this material can bring to earthquake prone regions. One of the most important advantages compared to the traditional isolation systems is the feasibility in the installation of the mixture in order to work as a seismic isolator. In addition to that, the mixture is considered to be an affordable material for the developing countries that are affected by the effects of earthquakes.

Consequently, the use of rubber-soil mixture as part of the soil foundation would reduce vibrations coming from earthquakes not only in new constructions but also existing buildings. Thus, this new technique of constructing the soil foundation would enhance the performance of constructions during seismic events reducing the number of buildings collapsed due to dynamic vibrations.