
Evaluation of internal and external stresses on the SPT sampler
Author(s) -
Juliana Zapata Galvis,
Edmundo Rogério Esquivel
Publication year - 2016
Publication title -
dyna
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.164
H-Index - 18
eISSN - 2346-2183
pISSN - 0012-7353
DOI - 10.15446/dyna.v83n195.51138
Subject(s) - internal friction , settlement (finance) , foundation (evidence) , geotechnical engineering , acceleration , cylinder , internal forces , extractor , mechanics , structural engineering , environmental science , mechanical engineering , engineering , materials science , physics , computer science , classical mechanics , composite material , process engineering , archaeology , world wide web , payment , history
The N SPT index is usually used in empirical correlations to estimate parameters of the soil, carrying capacity, foundation settlement, etc. Because these correlations have no scientific basis, researchers have been developing rational methods of analysis, based on energy concepts. The amounts of energy involved in the SPT test are evaluated by the EFV method. With force and acceleration records, amounts of energy, equipment efficiency, experimental dynamic reaction force of the soil and stresses acting on the sampler were assessed. In this study, a sample extractor system was designed, which consists of a base, a hydraulic cylinder and a load cell. The objective of this equipment is to experimentally quantify the internal friction force, allowing the stresses acting on the sampler to be evaluated. Also, the Aoki's a parameter, which is the ratio of internal friction and external friction between the ground and the sampler, could be calculated.