Innovative techniques for ground improvement

Ground improvement methods to ensure structure’s safety under static conditions, and to mitigate seismic risk of structures and infrastructures, became during the last years a challenging research topic with substantial economic interest in global scale. Soil mixtures (essentially sand and gravels) with lightweight geomaterials (such as volcanic pumice or other industrial materials, as recycled car tires after special processing) are commercially available in the form of grains in a variety of sizes, and present an attractive solution to improve structural safety and to reduce the seismic risk. At the same time, such mixtures offer an interesting solution to the eco-friendly use of recycled materials. Our research activities focus on:

• Laboratory testing of the mechanic and dynamic properties of soil mixtures with volcanic coarse materi­als and granulated rubber derived from recycled used tires
• Investigation of factors influencing the dynamic properties of the mixtures (i.e. percentage of rubber, size of the granules, ratio of the mean diameter between the soil and the synthetic material)
• Proposal of analytical expressions for the dynamic properties of lightweight mixture materials and of the best practices for specific applications in a wide range of cyclic strains and compositions
• Numerical analysis of the seismic response of different structures (i.e. buildings, tanks, bridge piers and abutments) and geo-structures (i.e. retaining walls and embankments) using the rubber/pumice soil mix­tures as foundation or backfill material, in order to evaluate the improved earthquake behavior and the most influencing parameters