Dynamic elasticity and strength anisotropy of some surficial rocks
Titel:
Dynamic elasticity and strength anisotropy of some surficial rocks
Auteur:
Inyang, H. I. Fish, K.
Verschenen in:
International journal of mining, reclamation and environment
Paginering:
Jaargang 6 (1992) nr. 2 pagina's 65-71
Jaar:
1992
Inhoud:
Rock mass classification systems that comprise both rock material properties and large-scaldiscontinuities are essential in surface mining operations, tunneling and rock foundation engineering. As reported in this paper, point load strength measurements made on limestone, sandstone, granite, basalt and syenite rock samples indicate anisotropy ratios (axial to diametral) ranging approximately from 2.0 to 9.5. In general, direct proportionality exists between measured strength values in the two orthogonal directions. Furthermore, axial and diametral strength values are respectively, directly proportional to the dynamic elastic modulus of the samples. Values for the latter were obtained indirectly through density and sonic wave transit time measurements. Although it is known to be significant in rock excavation processes, rock quality designation (RQD) exhibits no discernible relationship with elastic modulus or point load strength of each of the rock samples tested. Along with the results of previous investigations, experimental data obtained in this investigation are used to discuss the utility of combining rock material strength measures and information on the distribution of joints (beyond the scale of small test samples) to characterize rock masses.