Web-based Class Project on Rock Mechanics In Situ Shear Wave Velocity Measurements in Rocks Prepared by: William Greenwood Report prepared as part of course CEE 544: Rock Mechanics Winter 2015 Semester Instructor: Professor Dimitrios Zekkos Department of Civil and Environmental Engineering University of Michigan With the Support of:

Outline In Situ Tests Shear Wave Velocity Case Study Soils and Rocks Applications Vs of Rocks In Situ Tests Refraction Reflection Surface Waves Borehole Methods Case Study Ellefson et al. (2012) Fracture Zone Identification

Physical and Chemical Weathering Soils and Rocks Site investigations often involve both soil and rock Vp,soil is very sensitive to saturation Stokoe et al. (2004) Rock For a fully-saturated soil: Vp,soil = Vp,water Between 0-100% saturation, Vp,rock may only change by a few percent. Physical and Chemical Weathering Soil

Applications Small-Strain Shear Modulus Foundation Design Gazetas (1991) Small-Strain Shear Modulus Foundation Design NIBS (2010) Rathje and Kottke (2010) Seismic Site Response Analyses Building Codes Various correlations, and much more.

Shear Wave Velocity of Some Rock Types Velocities are highly dependent on degree of weathering The Vs of a material may change by an order of magnitude over a relatively short distance

Surface Tests for Shear Wave Velocity Stokoe et al. (2004) Stokoe et al. (2004) Refraction Survey Reflection Survey See also: ASTM D5777 ASTM D7128 Stokoe et al. (1994) Park et al., (1998) Sahadewa et al. (2012) Surface Waves (MASW)

Borehole Tests for Shear Wave Velocity Stokoe and Santamarina (2000) Stokoe and Santamarina (2000) Crosshole Test Suspension Logging See also: ASTM D7400 ASTM D4428 Kitsunezaki (1980) Woods (1994) Stokoe and Santamarina (2000) Downhole Test

Case Study: Ellefson et al. (2012) Characterization of geologic framework at a contaminated site in West Trenton, NJ, USA Groundwater contaminated with chlorinated solvents from the Naval Air Warfare Center (NAWC) Ellefson et al. (2012)

Case Study: Ellefson et al. (2012) Fault locations estimated from geologic mapping and previous site investigations Two boreholes drilled to estimate orientation of faults and extent of discontinuities Ellefson et al. (2012)

Case Study: Ellefson et al. (2012) Two seismic transects for refraction surveys were used in conjunction with other investigations Low velocity zones identified as the extents of the fault zones Ellefson et al. (2012)

References ASTM Standard D4428. (2014). “Standard Test Methods for Crosshole Seismic Testing.” ASTM International, West Consohocken, PA. ASTM Standard D5777. (2011). “Standard Guide for Using the Seismic Refraction Method for Subsurface Investigation.” ASTM International, West Consohocken, PA. ASTM Standard D7128. (2010). “Standard Guide for Using the Seismic Reflection Method for Shallow Subsurface Investigation.” ASTM International, West Consohocken, PA. ASTM Standard D7400. (2014). “Standard Test Methods for Downhole Seismic Testing.” ASTM International, West Consohocken, PA. Ellefson, K. J., Burton, W. C., and Lacombe, P. J. (2012). “Integrated Characterization of the Geologic Framework of a Contaminated Site in West Trenton, New Jersey.” J. of Applied Geophysics, 79, 71-81. Gazetas, G. (1991). ”Formulas and Charts for Impedances of Surface and Embedded Foundations.” J. Geotech. Engrg., 117(9), 1363–1381. Kitsunezaki, C. (1980). “A New Method for Shear Wave Logging.” Geophysics, 45, 1489-1506. Rathje, E. M., and Kottke, A. (2010). "Strata," https://nees.org/resources/strata. Sahadewa, A., Zekkos, D., and Woods, R. D. (2012). “Observations from the Implementation of a Combined Active and Passive Surface Wave Based Methodology.” Proc. State of the Art and Practice in Geotechnical Engineering (Geocongress 2012), 2786-2795. Stokoe, K. H., II, Joh, S. –H., and Woods, R. D. (2004). “Some Contributions of in Situ Geophysical Measurements to Solving Geotechnical Engineering Problems.” International Conference on Site Characterization, Porto, Portugal. Stokoe, K.H., II and Santamarina, J.C. (2000). “Seismic-wave Based Testing in Geotechnical Engineering.” Plenary Paper, International Conference on Geotechnical and Geological Engineering, GeoEng 2000, Melbourne, Australia, pp. 1490-1536. (2010). “Earthquake Resistant Design Concepts.” FEMA P-749 December 2010, National Institute of Building Sciences.

More Information More detailed technical information on this project can be found at: http://www.geoengineer.org/education/web-based-class-projects/rock-mechanics