Abstract
Finite element modelling of jointed rock masses requires detailed input data concerning the mechanical behaviour of the relevant joint sets. In the case of the Naesliden project, the properties of the footwall and hanging wall contacts were of particular concern because of their planarity. Methods of estimating the full-scale shear strength and shear stiffness are summarized. The estimates are based on assessment of full-scale values of the joint roughness coefficient (JRC), the joint wall compressive strength (JCS) and the residual friction angle. Sensitivity analyses indicate which of these parameters need to be determined with greatest accuracy at the levels of normal stress of interest. The full-scale estimates are compared with laboratory scale data and with data obtained from small scale tilt tests and tests on model tension fractures. A scale effect makes direct application of laboratory data of doubtful value. A simple dimensionless shear force-displacement formulation is suggested that describes the mobilization and subsequent reduction of joint roughness, as peak strength is exceeded during a given shearing event. The effect of changing normal stress during shearing is accounted for using this method.
Citation Formats
Barton, N.
Estimation of in-situ joint properties, Naesliden Mine.
Sweden: N. p.,
1980.
Web.
Barton, N.
Estimation of in-situ joint properties, Naesliden Mine.
Sweden.
Barton, N.
1980.
"Estimation of in-situ joint properties, Naesliden Mine."
Sweden.
@misc{etde_8489276,
title = {Estimation of in-situ joint properties, Naesliden Mine}
author = {Barton, N.}
abstractNote = {Finite element modelling of jointed rock masses requires detailed input data concerning the mechanical behaviour of the relevant joint sets. In the case of the Naesliden project, the properties of the footwall and hanging wall contacts were of particular concern because of their planarity. Methods of estimating the full-scale shear strength and shear stiffness are summarized. The estimates are based on assessment of full-scale values of the joint roughness coefficient (JRC), the joint wall compressive strength (JCS) and the residual friction angle. Sensitivity analyses indicate which of these parameters need to be determined with greatest accuracy at the levels of normal stress of interest. The full-scale estimates are compared with laboratory scale data and with data obtained from small scale tilt tests and tests on model tension fractures. A scale effect makes direct application of laboratory data of doubtful value. A simple dimensionless shear force-displacement formulation is suggested that describes the mobilization and subsequent reduction of joint roughness, as peak strength is exceeded during a given shearing event. The effect of changing normal stress during shearing is accounted for using this method.}
place = {Sweden}
year = {1980}
month = {May}
}
title = {Estimation of in-situ joint properties, Naesliden Mine}
author = {Barton, N.}
abstractNote = {Finite element modelling of jointed rock masses requires detailed input data concerning the mechanical behaviour of the relevant joint sets. In the case of the Naesliden project, the properties of the footwall and hanging wall contacts were of particular concern because of their planarity. Methods of estimating the full-scale shear strength and shear stiffness are summarized. The estimates are based on assessment of full-scale values of the joint roughness coefficient (JRC), the joint wall compressive strength (JCS) and the residual friction angle. Sensitivity analyses indicate which of these parameters need to be determined with greatest accuracy at the levels of normal stress of interest. The full-scale estimates are compared with laboratory scale data and with data obtained from small scale tilt tests and tests on model tension fractures. A scale effect makes direct application of laboratory data of doubtful value. A simple dimensionless shear force-displacement formulation is suggested that describes the mobilization and subsequent reduction of joint roughness, as peak strength is exceeded during a given shearing event. The effect of changing normal stress during shearing is accounted for using this method.}
place = {Sweden}
year = {1980}
month = {May}
}