Evaluation of rock mechanical behaviors under uniaxial compression with reference to assessed weathering grades


Autoria(s): BASU, A.; CELESTINO, T. B.; BORTOLUCCI, A. A.
Contribuinte(s)

UNIVERSIDADE DE SÃO PAULO

Data(s)

18/10/2012

18/10/2012

2009

Resumo

A weathering classification for granitic rock materials from southeastern Brazil was framed based on core characteristics. The classification was substantiated by a detailed petrographic study. Indirect assessment of weathering grades by density, ultrasonic and Schmidt hammer index tests was performed. Rebound values due to Schmidt hammer multiple impacts at one representative point were more efficient in predicting weathering grades than averaged single impact rebound values, P-wave velocities and densities. Uniaxial compression tests revealed that a large range of uniaxial compressive strength (214-153 MPa) exists in Grade I category where weathering does not seem to have played any role. It was concluded that variability in occurrences of quartz intragranular cracks and in biotite percentage, distribution and orientation might have played a key role in accelerating or decelerating the failure processes of the Grade I specimens. Deterioration of uniaxial compressive strength and elastic modulus and increase in Poisson`s ratio with increasing weathering intensity could be attributed to alteration of minerals, disruption of rock skeleton and microcrack augmentation. A crude relation between failure modes and weathering grades also emerged.

Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)

Identificador

ROCK MECHANICS AND ROCK ENGINEERING, v.42, n.1, p.73-93, 2009

0723-2632

http://producao.usp.br/handle/BDPI/17907

10.1007/s00603-008-0170-2

http://dx.doi.org/10.1007/s00603-008-0170-2

Idioma(s)

eng

Publicador

SPRINGER WIEN

Relação

Rock Mechanics and Rock Engineering

Direitos

restrictedAccess

Copyright SPRINGER WIEN

Palavras-Chave #Weathering classification #granite #index tests #uniaxial compressive strength #Young`s modulus #Poisson`s ratio #failure modes #SCHMIDT HAMMER #HONG-KONG #MICROCRACKS #GRANITE #Engineering, Geological #Geosciences, Multidisciplinary
Tipo

article

original article

publishedVersion