Analysis of the behavior of piled rafts with and without defective piles when horizontally loaded in soil from Campinas region, SP

• Grant number: 14/06611-4
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2015
• End date: February 28, 2017
• Field of knowledge: Engineering - Civil Engineering - Geotechnical Engineering
• Principal Investigator: Paulo José Rocha de Albuquerque
• Grantee: Paulo José Rocha de Albuquerque
• Host Institution: Faculdade de Engenharia Civil, Arquitetura e Urbanismo (FEC). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated researchers: Renato Pinto da Cunha

Abstract

This project aims to know the behavior of piled rafts foundations with and without defective piles when laterally loaded, by testing an already executed group of piled raft system executed with bored piles with 5.0 m in length and 0.25 m in diameter. These piles will be founded into a diabase deposit at the Research Site of Soil Mechanics and Foundations from the Faculty of Civil Engineering, Architecture and Urbanism of the Unicamp; the subsoil from this area is usually formed by layers of sandy silt upper and silty sand underneath. In this site several laboratory tests have already been carried out with undisturbed soil samples retrieved from inspection wells, and some in situ tests were already carried out as SPT-T, DMT, CPT, DPL via previously supported research project from CNPq.Static horizontal load tests will be performed in accordance to theNBR12131/2006 and ASTM D3966/2007 prescriptions, on piled raft systems composed by one, two, three and four piles respectively, with and without contact of the cap on the natural ground; other tests will also be carried out in three piled rafts systems which already have one defective pile in each one of them, to know the behavior of these foundations under such extreme conditions. It is worth saying that some of these structures were already built at the experimental field as part of the project Fapesp 2011/17959-3.As previously stated, it will be built as part of this research three extra piled raft systems with one, three and four piles with 0.30 m of diameter, and length of 5.0 m, with inclinometer tubes placed in the center of each pile to use the inclinometer torpedo. It will also be built another three isolated concrete piles with 0.25 m of diameter and auger length of 5.0 m, which present several and different sorts of defective piles (structural damages). In all these new concrete structures, it will be done integrity test (PET) before execution of the top cap, just for qualitative analysis of the damage into the structural element. All blocks will have contact with the ground.Numerical analyses of the results will also be done by using well recognized soil models and computational tools, aiming the simulation and evaluation of 3D behavior of the foundations, besides of the simulation of the defective piles. It is hoped herein the advance in the knowledge of the behavior of piled rafts, with the aim to foster to technical area with guidelines for better elaboration of technical designs and execution processes of this type of foundation.With this project a 2 Doctorate Thesis, one Master Thesis and some Scientific Initiation Projects will be achieved. It is worthy to emphasize that the working group will count with researchers from the University of Brasília (UnB), whose members have vast experience in investigations of this type of foundation. (AU)