Strength Envelopes of Florida Carbonate Rocks near Ground Surface
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 145, Issue 8
Abstract
Florida carbonate rocks are typically weak, with a median unconfined compressive strength value of approximately 3 MPa. Due to the infeasibility of attaching strain gauges to their vuggy and shelly surfaces, an innovative volume change device was added to a Hoek cell triaxial system, enabling the measurement of volumetric responses during triaxial tests. In this study, 223 triaxial tests on five different Florida rock formations were performed, with confining pressures ranging from 0.35 to 20.7 MPa. The tests indicate that (1) only a small percentage of Florida carbonate rocks exhibit brittle rupture; and (2) most Florida carbonate rocks exhibit ductile stress-strain behavior, even at the lowest confining pressure. A ductile response is typically associated with contractive volumetric behavior due to the rock’s porous structure. The study established a ductile threshold ratio, which was found to not be a constant, but to vary with confining pressure. It was confirmed through the triaxial test results that (1) the Hoek-Brown criterion works well for the dense specimens, which are not commonly encountered in Florida; and (2) for the typical porous Florida rocks, the stress-strain response is ductile and the strength envelopes in Lambe’s diagram have a linear increasing (constant slope) zone followed by a decreasing slope zone, which is a function of the Florida formations as well as the specimens’ bulk dry unit weights.
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References
AASHTO. 2017. AASHTO LRFD bridge design specification. Washington, DC: AASHTO.
ASTM. 2016. Standard test method for splitting tensile strength of intact rock core specimens. ASTM D3967. West Conshohocken, PA: ASTM.
Briaud, J.-L., B. Smith, K-Y. Rhee, H. Lacy, and J. Nicks. 2009. “The Washington Monument case history.” Int. J. Geoeng. Case Histories 1 (3): 170–188.
Brown, D., J. P. Turner, and R. J. Castelli. 2010. Drilled shafts: Construction procedures and LRFD design methods. Washington, DC: Federal Highway Administration.
Carter, J. P., and F. H. Kulhawy. 1988. Analysis and design of drilled shaft foundations socketed into rock. New York: Empire State Electric Engineering Research Corporation and Electric Power Research Institute.
Eagar, T. W., and C. Musso. 2001. “Why did the World Trade Center collapse? Science, engineering, and speculation.” JOM 53 (12): 8–11. https://doi.org/10.1007/s11837-001-0003-1.
Elliott, G. M., and E. T. Brown. 1985. “Yield of a soft, high porosity rock.” Geotechnique 35 (4): 413–423. https://doi.org/10.1680/geot.1985.35.4.413.
FDOT (Florida DOT). 2018. Soils and foundations handbook. Davie, FL: State Materials Office.
Fereidooni, D., and R. Khajevand. 2018. “Determining the geotechnical characteristics of some sedimentary rocks from Iran with an emphasis on the correlations between physical, index, and mechanical properties.” Geotech. Test. J. 41 (3): 20170058. https://doi.org/10.1520/GTJ20170058.
Gowd, T. N., and F. Rummel. 1977. “Effect of fluid injection on the fracture behavior of porous rock.” Int. J. Rock Mech. Min. Sci. Geomech. Abstr. 14 (4): 203–208. https://doi.org/10.1016/0148-9062(77)90949-4.
Hoek, E., and E. T. Brown. Forthcoming. “The Hoek–Brown failure criterion and GSI—2018 edition.” J. Rock Mech. Geotech. Eng. https://doi.org/10.1016/j.jrmge.2018.08.001.
Hoek, E., and E. T. Brown. 1980. “Empirical strength criterion for rock masses.” J. Geotech. Eng. Div. 106 (9): 1013–1035.
Hoek, E., and E. T. Brown. 1988. “The Hoek-Brown failure criterion—A 1988 update.” In Proc., 15th Canadian Rock Mechanics Symp., edited by J. H. Curran, 31–38. Toronto: Univ. of Toronto.
Hoek, E., C. Carranza-Torres, and B. Corkum. 2002. “Hoek-Brown failure criterion—2002 edition.” In Proc., Mining and Tunnelling Innovation and Opportunity, 5th North American Rock Mechanics Symp. and 17th Tunnelling Association of Canada Conf., 267–273. Toronto: Univ. of Toronto.
Hoek, E., and J. A. Franklin. 1968. “Simple triaxial cell for field or laboratory testing of rock.” Trans. Inst. Min. Metall. Sect. A 77: 22–26.
Johnston, I. W. 1985. “Strength of intact geomechanical materials.” J. Geotech. Eng. 111 (6): 730–749. https://doi.org/10.1061/(ASCE)0733-9410(1985)111:6(730).
Kimmerling, R. 2002. Geotechnical engineering circular no. 6: Shallow foundations. Washington, DC: Federal Highway Administration.
Lambe, T. W., and R. V. Whitman. 1969. Soil mechanics. New York: Wiley.
Mogi, K. 1965. “Deformation and fracture of rocks under confining pressure (2): Elasticity and plasticity of some rocks.” Bull. Earthquake Res. Inst. 42: 349–379.
Mogi, K. 1966. “Pressure dependence of rock strength and transition from brittle to ductile flow.” Bull. Earthquake Res. Inst. 44: 215–232.
Nguyen, T., M. C. McVay, D. Horhota, and R. Herrera. 2018. “Overview of carbonate-rocks and IGMs supporting Florida bridges.” In Proc., 52nd US Symp. on Rock Mechanics. Alexandria, VA: American Rock Mechanics Association.
Paikowsky, S. G., M. C. Canniff, K. Lesny, A. Kisse, S. Amatya, and R. Muganga. 2010. LRFD design and construction of shallow foundations for highway bridge structures. Washington, DC: Transportation Research Board.
Perras, M. A., and M. S. Diederichs. 2014. “A review of the tensile strength of rock: Concepts and testing.” Geotech. Geol. Eng. J. 32 (2): 525–546. https://doi.org/10.1007/s10706-014-9732-0.
Schwartz, A. E. 1964. “Failure of rock in the triaxial shear test.” In Proc., 6th US Symp. on Rock Mechanics, 109–151. Alexandria, VA: American Rock Mechanics Association.
Truzman, M. 2016. “Use of geological strength index to characterize the miami limestone for shallow foundation design.” In Proc., 50th US Rock Mechanics/Geomechanics Symp. Alexandria, VA: American Rock Mechanics Association.
Wong, T., C. David, and W. Zhu. 1997. “The transition from brittle faulting to cataclastic flow in porous sandstones: Mechanical deformation.” J. Geophys. Res. 102 (B2): 3009–3025. https://doi.org/10.1029/96JB03281.
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©2019 American Society of Civil Engineers.
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Received: Sep 26, 2018
Accepted: Jan 11, 2019
Published online: Jun 11, 2019
Published in print: Aug 1, 2019
Discussion open until: Nov 11, 2019
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