Ultrasonic wave velocities as a diagnostic tool for the quality assessment of marble

Abstract Marbles are frequently used as building stones even if they mostly show a limited durability. Thus, different marbles with different fabric types and states of preservation have been investigated in order to constrain the interaction between fabric, state of deterioration and ultrasonic wave velocities. Experimental data reveal that the state of preservation of a marble is clearly documented by ultrasonic wave velocities of compressional waves. For a maximum porosity of up to 1% velocities determined on dry samples range from about 1 km s−1 to over 6 km s−1. Anisotropy of ultrasonic wave velocities is a common feature of marbles due to a lattice preferred orientation of the anisotropic rock-forming minerals calcite and dolomite. Pre-existing and thermally induced microcracks tend to increase this anisotropy. For Lasa marble, this increase can be explained by a coincidence of intrinsic anisotropy and the effect of pre-existing and thermally induced microcracks. For many marbles, velocities are reduced to at about 1 km s−1 as a consequence of thermal degradation due to only one heating cycle up to 100°C. Model calculations reveal that the velocity reduction is caused by cracks with an extremely small aspect ratio of about 0.005 or even less. The porosity associated with this very early stage of deterioration will not be increased significantly and thus, thermal degradation cannot be determined by other petrophysical measurements.

[1]  J. Fredrich,et al.  Micromechanics of thermally induced cracking in three crustal rocks , 1986 .

[2]  Manika Prasad,et al.  Structural damage evaluation of natural building stones: Potential and limitations of ultrasonic diagnostics , 1999 .

[3]  Siegfried Siegesmund,et al.  Physical weathering of marbles caused by anisotropic thermal expansion , 2000 .

[4]  Helmut Dürrast,et al.  Die Schadensanalyse von Naturwerksteinen mittels Ultraschalldiagnostik: Möglichkeiten und Grenzen , 1999 .

[5]  Bernd Leiss,et al.  Fabric anisotropy and its influence on physical weathering of different types of Carrara marbles , 2000 .

[6]  A. Reuss,et al.  Berechnung der Fließgrenze von Mischkristallen auf Grund der Plastizitätsbedingung für Einkristalle . , 1929 .

[7]  N. Christensen.  Compressional wave velocities in metamorphic rocks at pressures to 10 kilobars , 1965 .

[8]  R. Arts,et al.  13. Experimental and Theoretical Tools for Characterizing Anisotropy Due to Mechanical Defects in Rocks under Varying Pore and Confining Pressures , 1996 .

[9]  S. Siegesmund,et al.  Thermal expansion and its control on the durability of marbles , 2002, Geological Society, London, Special Publications.

[10]  E. Tschegg,et al.  Reasons for insufficient shape stability of marble plates , 1999 .

[11]  S. Siegesmund,et al.  Thermal tresses and microcracking in calcite and dolomite marbles via finite element modelling , 2002, Geological Society, London, Special Publications.

[12]  Z. Hashin.  Analysis of Composite Materials—A Survey , 1983 .

[13]  S. Siegesmund,et al.  The Significance of rock fabrics for the geological - interpretation of geophysical anisotropies , 1996 .

[14]  A. R. Gregory,et al.  An experimental investigation of factors affecting elastic wave velocities in porous media , 1958 .

[15]  S. Siegesmund,et al.  Characterization of crack distribution: fabric analysis versus ultrasonic inversion , 2000 .

[16]  F. Birch.  The velocity of compressional waves in rocks to 10 kilobars: 1. , 1960 .

[17]  Olivier Coussy,et al.  Acoustics of Porous Media , 1988 .

[18]  A. R. Gregory,et al.  ELASTIC WAVE VELOCITIES IN HETEROGENEOUS AND POROUS MEDIA , 1956 .

[19]  Elmar Karl Tschegg,et al.  Anisotropic Thermal Expansion Causes Deformation of Marble Claddings , 1996 .

[20]  Bernard Budiansky,et al.  Seismic velocities in dry and saturated cracked solids , 1974 .

[21]  Siegfried Siegesmund,et al.  Natural Stone, Weathering Phenomena, Conservation Strategies and Case Studies , 2003 .