Influence of water content on torque versus angle of rotation degree shape in the SPT-T test

• Grant number: 06/06853-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2007
• End date: October 31, 2007
• Field of knowledge: Engineering - Civil Engineering - Geotechnical Engineering
• Principal Investigator: Anna Silvia Palcheco Peixoto
• Grantee: Ana Carolina Fausto Girio
• Host Institution: Faculdade de Engenharia (FE). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil

Abstract

In Brazilian foundation practice, SPT Test is generally used in the design of pile and shallow foundations. By the way, Mayne (2001) inquire how just a number (N-value) is enough to estimate a great number of different soil parameters and advocated the use of in situ testing with hybrid devices. Ranzini (1988) just already suggested supplementing the conventional SPT with measurement of the torque required to turn the split spoon after driving. After this, some engineers began to use that new technique. Peixoto (2001), in her Ph.D. Thesis "The SPT-T Test and his Application in Foundation Engineering”, studied several aspects of that test: the behavior of the torque versus rotation degree shape; the T/N ratio; the speed test and a suggestion of a method to predict the bearing capacity of piles. Carvalho et al. (2001) showed that both N value and T, torque measurement, are influenced by suction soil. But, it is necessary to do an evaluation how it is relevant in engineering practice. In this manner, this research are planning to study the water content influence on torque measurement.