An Empirical Correlation of Index Geomechanical Parameters with the Compressional Wave Velocity

The geomechanical strength of rockmass plays a key role in planning and design of mining and civil construction projects. Determination of geomechanical properties in the field as well as laboratory is time consuming, tedious and a costly affair. In this study, density, slake durability index, uniaxial compressive strength (UCS) and P-wave velocity tests were conducted on four igneous, six sedimentary and three metamorphic rock varieties. These properties are crucial and used extensively in geotechnical engineering to understand the stability of the structures. The main aim of this study is to determine the various mechanical properties of 13 different rock types in the laboratory and establish a possible and acceptable correlation with P-wave velocity which can be determined in the field as well as laboratory with ease and accuracy. Empirical equations were developed to calculate the density, slake durability index and UCS from P-wave velocities. Strong correlations among P-wave velocity with the physical properties of different rock were established. The relations mainly follow a linear trend. Student’s ‘t’ test and ‘F’ test were performed to ensure proper analysis and validation of the proposed correlations. These correlations can save time and reduce cost during design and planning process as they represent a reliable engineering tool.

[1]  V. S. Vutukuri,et al.  Handbook on Mechanical Properties of Rocks , 1977 .

[2]  H. Hardy.  Handbook on mechanical properties of rocks: Vol. 1. V. S. Vutukuri, R. D. Lama, and S. S. Saluja. Trans Tech Publications, D-3392 Clausthal, Germany. , 1976 .

[3]  J. J. Hill,et al.  Seismic spectroscopy in fracture characterization , 1985, Quarterly Journal of Engineering Geology.

[4]  T. Singh,et al.  Assessment of tunnel instability—a numerical approach , 2010 .

[5]  Mustafa Laman,et al.  Settlement and slaking problems in the world's fourth largest rock-fill dam, the Ataturk Dam in Turkey , 2000 .

[6]  J. Franklin,et al.  The slake-durability test , 1972 .

[7]  C. Oguchi,et al.  Effect of porosity on the increase in weathering-rind thicknesses of andesite gravel , 1999 .

[8]  Jerome V. DeGraff,et al.  Principles of engineering geology , 1988 .

[9]  Giovanni B. Crosta,et al.  Slake durability vs ultrasonic treatment for rock durability determinations , 1998 .

[10]  Masahiro Chigira,et al.  Weathering rate of mudstone and tuff on old unlined tunnel walls , 2000 .

[11]  S. Kahraman,et al.  Determination of physical properties of carbonate rocks from P-wave velocity , 2008 .

[12]  V. Gupta,et al.  The effect of pH of water and mineralogical properties on the slake durability (degradability) of different rocks from the Lesser Himalaya, India , 2007 .

[13]  Candan Gokceoglu,et al.  Factors affecting the durability of selected weak and clay-bearing rocks from Turkey, with particular emphasis on the influence of the number of drying and wetting cycles , 2000 .

[14]  Paul M. Santi,et al.  Predicting the unconfined compressive strength of the Breathitt shale using slake durability, Shore hardness and rock structural properties , 1999 .

[15]  T. Singh,et al.  Prediction of p -wave velocity and anisotropic property of rock using artificial neural network technique , 2004 .

[16]  B. M. New,et al.  P-wave velocity measurements in a machine-bored, chalk tunnel , 1980, Quarterly Journal of Engineering Geology.

[17]  P. Gaviglio.  Longitudinal waves propagation in a limestone: The relationship between velocity and density , 1989 .

[18]  G. H. F. Gardner,et al.  FORMATION VELOCITY AND DENSITY—THE DIAGNOSTIC BASICS FOR STRATIGRAPHIC TRAPS , 1974 .

[19]  Abdul Shakoor,et al.  Characterizing durability of mudrocks for slope stability purposes , 1995 .

[20]  J. Delgado Rodrigues,et al.  Physical Characterization and Assessment of Rock Durability Through Index Properties , 1991 .

[21]  Atiye Tugrul,et al.  Reply to discussion by Larson and Tullborg on “The effect of weathering on pore geometry and compressive strength of selected rock types from Turkey” by Tuğrul, Engineering Geology, 75: 215–227 (2004) , 2006 .

[22]  E. T. Brown.  Rock characterization, testing & monitoring: ISRM suggested methods , 1981 .

[23]  D. Deere,et al.  Engineering classification and index properties for intact rock , 1966 .

[24]  E. Yaşar,et al.  Correlating sound velocity with the density, compressive strength and Young's modulus of carbonate rocks , 2004 .

[25]  S. P. Pradhan,et al.  Tensile Strength of Rock Under Elevated Temperatures , 2011 .

[26]  Manoj Khandelwal,et al.  A correlation between Schmidt hammer rebound numbers with impact strength index, slake durability index and P-wave velocity , 2011 .

[27]  M. Vidal,et al.  pH(stat) vs. single extraction tests to evaluate heavy metals and arsenic leachability in environmental samples. , 2009, Analytica chimica acta.

[28]  S. Kahraman.  Evaluation of simple methods for assessing the uniaxial compressive strength of rock , 2001 .

[29]  T. Singh,et al.  A correlation between P-wave velocity, impact strength index, slake durability index and uniaxial compressive strength , 2008 .

[30]  S. P. Pradhan,et al.  Stability of slopes in a fire-prone mine in Jharia Coalfield, India , 2013, Arabian Journal of Geosciences.

[31]  M. Gladwin,et al.  Ultrasonic stess monitoring in underground mining , 1982 .

[32]  J. P. Harrison,et al.  A mechanical degradation index for rock , 2001 .

[33]  Manoj Khandelwal,et al.  Effect of pH on the physico-mechanical properties of marble , 2007 .

[34]  İ. Çobanoğlu,et al.  Estimation of uniaxial compressive strength from point load strength, Schmidt hardness and P-wave velocity , 2008 .

[35]  A. Tugrul,et al.  The effect of weathering on pore geometry and compressive strength of selected rock types from Turkey , 2004 .

[36]  T. Singh,et al.  Slake durability study of shaly rock and its predictions , 2005 .

[37]  Ana-María Fuertes,et al.  Sieve bootstrap t-tests on long-run average parameters , 2008, Comput. Stat. Data Anal..

[38]  Katsuhiko Kaneko,et al.  Slake durability and mineralogical properties of some pyroclastic and sedimentary rocks , 2002 .

[39]  Masayasu Inoue,et al.  Relation Between Uniaxial Compressive Strength And Elastic Wave Velocity of Soft Rock , 1981 .