Relationship between aggregate microstructure and mortar expansion. A case study of deformed granitic rocks from the Santa Rosa mylonite zone

It is shown that the deformation state of a granitic rock has a profound impact on the long-term stability of concrete, if used as aggregate due to enhanced susceptibility to the alkali-silica reaction. An investigation of the microstructure of granitic rocks from the Santa Rosa mylonite zone in southern California with transmission electron microscopy and neutron diffraction revealed that, as these rocks become progressively deformed from granite to mylonite and phyllonite, accompanied by grain size reduction, the dislocation density in quartz (investigated with TEM) increases and preferred orientation of biotite (determined by neutron diffraction) becomes stronger. While the contribution of dislocations to the bulk energy increase of quartz is low, dislocations provide favorable sites for dissolution and precipitation to occur. A comparison with ASTM C 1260 expansion tests of these same samples indicates that expansion increases with the dislocation density.

[1]  H. Wenk Electron microscopy in mineralogy , 1976 .

[2]  A. Lasaga,et al.  The effect of dislocation density on the dissolution rate of quartz , 1990 .

[3]  J. Pannetier,et al.  Texture development in deformed granodiorites from the Santa Rosa mylonite zone, southern California , 1990 .

[4]  W. Casey,et al.  Crystal defects and the dissolution kinetics of rutile , 1988 .

[5]  A. Lasaga,et al.  Surface chemistry, etch pits and mineral-water reactions , 1986 .

[6]  S. Matthies,et al.  On the Reproduction of the Orientation Distribution Function of Texturized Samples from Reduced Pole Figures Using the Conception of a Conditional Ghost Correction , 1982 .

[7]  H. Wenk DEFORMATION OF MYLONITES IN PALM CANYON, CALIFORNIA, BASED ON XENOLITH GEOMETRY , 1998 .

[8]  H. C. Heard,et al.  Mechanical twinning and slip in experimentally deformed plagioclases , 1969 .

[9]  H. Wenk,et al.  Preferred orientation of phyllosilicates in phyllonites and ultramylonites , 1987 .

[10]  D. Mainprice,et al.  Deformation mechanisms in a high-temperature quartz-feldspar mylonite: evidence for superplastic flow in the lower continental crust , 1987 .

[11]  H. Wenk,et al.  BEARTEX: a Windows-based program system for quantitative texture analysis , 1998 .

[12]  H. Wenk,et al.  Texture analysis with the new HIPPO TOF diffractometer , 2003 .

[13]  P. Bird,et al.  Dissolution of quartz in aqueous basic solution, 106-236 C - Surface kinetics of 'perfect' crystallographic faces , 1990 .

[14]  H. Heinisch,et al.  Elastic stresses and self-energies of dislocations of arbitrary orientation in anisotropic media: Olivine, orthopyroxene, calcite, and quartz , 1975 .

[15]  H. Wenk,et al.  The Microstructure of Some Naturally Deformed Quartzites , 1976 .

[16]  N. Cabrera,et al.  XLV. On the dislocation theory of evaporation of crystals , 1956 .

[17]  P. Somasundaran,et al.  Introduction to surface chemistry and catalysis , 1997 .

[18]  G. R. Holdren,et al.  Bulk dislocation densities and dissolution rates in a calcic plagioclase , 1988 .

[19]  Hans-Peter Schertl,et al.  Geochim. cosmochim. acta , 1989 .

[20]  C. W. Burnham,et al.  The solubility of quartz in super-critical water , 1965 .

[21]  F. Augustine,et al.  Topography and ETCH patterns of synthetic quartz , 1960 .

[22]  W. K. Burton,et al.  The growth of crystals and the equilibrium structure of their surfaces , 1951, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[23]  L. Murr,et al.  Kinetic effects of particle-size and crystal dislocation density on the dichromate leaching of chalcopyrite , 1981 .

[24]  B. S. Gogte An evaluation of some common Indian rocks with special reference to alkali-aggregate reactions , 1973 .

[25]  R. Stallard,et al.  Dissolution at dislocation etch pits in quartz , 1986 .

[26]  R. Wintsch,et al.  The effect of dislocation density on the aqueous solubility of quartz and some geologic implications: A theoretical approach , 1985 .

[27]  P. Bennema,et al.  Thermodynamical stability conditions for the occurrence of hollow cores caused by stress of line and planar defects , 1982 .

[28]  J. Bogdanoff,et al.  On the Theory of Dislocations , 1950 .

[29]  H. Wenk,et al.  Development of phyllonite from granodiorite: Mechanisms of grain-size reduction in the Santa Rosa mylonite zone, California , 1995 .

[30]  Hans-Rudolf Wenk,et al.  Evidence for regional Dauphiné twinning in quartz from the Santa Rosa mylonite zone in Southern California. A neutron diffraction study , 2005 .

[31]  Gy. Zimonyi On the mechanism of the growth of quartz crystals , 1957 .

[32]  R. Hooton,et al.  ASR OF CONCRETE AGGREGATE QUARRIED FROM A FAULT ZONE: RESULTS AND PETROGRAPHIC INTERPRETATION OF ACCELERATED MORTAR BAR TESTS , 1992 .

[33]  J. Tullis,et al.  Energy associated with dislocations: A calorimetric study using synthetic quartz , 1995 .

[34]  Guk-Rwang Won American Society for Testing and Materials , 1987 .

[35]  S. Brantley,et al.  Dissolution kinetics of strained calcite , 1989 .