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FEBRUARY MEETING NOTICE
***Tuesday, February 12, 2013***

Topic: #1: "Approaching Geologic Variability with Outcrop Confidence, Geotechnical Complexity, and Quality Levels"

#2: "Reconnaissance-level terrestrial photogrammetry of rock slopes"

Speaker: Dr. Jeffrey Keaton, AMEC

Location: Steven's Steak House
5332 Stevens Place, City of Commerce, CA
(323) 723-9856

Date/Time: Tuesday, February 12, 2013
5:30pm - Social Hour
6:30pm - Dinner
7:30pm - Program

Cost: $30 per person with reservations, $35 without reservations (at the door), $15 for students with a valid Student ID

RSVP: PLEASE EMAIL SHANT MINAS AT: SHANT@AESSOIL.COM
or call (818) 552-6000 ext.109
PLEASE MAKE RESERVATIONS BY E-MAIL PRIOR TO 5 P.M., FRIDAY, FEBRUARY 8, 2013

Abstract #1:
Approaching Geologic Variability with Outcrop Confidence, Geotechnical Complexity, and Quality Levels

Geologic variability must be described explicitly for use in engineering reliability-based design projects. Current engineering practice treats subsurface conditions as "soil layers" and uses geotechnical parameters measured in the field or laboratory as surrogates for geology. Burland's (1987) Soil Mechanics Triangle is a useful starting point for geologic variability; it is modified into a Geologic Model representing the geologic conditions at a site relevant to a proposed project; a Ground Model representing the Geologic Model portrayed with engineering parameters; and a Geotechnical Model representing the Ground Model displaying design parameters and predicted performance of the project. NRCS (2002) Outcrop Confidence is a relative measure of predictability or homogeneity of the structural domain and lithology of rock units over a project site: OC-1 pertains to massive, homogeneous rock units that are vertically and laterally extensive at a site that has a history of low tectonic activity; OC-2 pertains to rock characteristics that are generally predictable, having expected lateral and vertical variability with tectonically produced structural features that tend to be systematic in orientation and spacing; OC-3 pertains to extremely variable rock conditions caused by complex depositional or structural history, mass movement, or buried topography. Sources of geotechnical complexity (Morgenstern and Cruden, 1977; Watters and Delahaut, 1995) are genetic (associated with original formation or deposition); epigenetic (associated with subsequent deformation or diagenesis and alteration); and surface weathering, including erosion and subsequent burial processes. Quality levels used in subsurface utility engineering (SUE) projects (FHWA, 2011) are analogous to geologic investigation levels: QL-D is based solely on existing information (desktop); QL-C includes field observations (reconnaissance); QL-B includes surface geophysics (limited verification); whereas QL-A includes subsurface investigation (verification). These processes and approaches, when combined, appear to provide a framework for estimating project-scale uncertainty and variability of geologic conditions at a site and are worthy of further consideration.

Geologic variability must be described explicitly for engineering reliability-based design projects. Engineering practice treats subsurface conditions as soil layers, using geotechnical field or laboratory parameters as surrogates for geology. Burland's Soil Mechanics Triangle is modified into a Geologic Model representing the geologic conditions at a site relevant to a proposed project; a Ground Model representing the Geologic Model portrayed with engineering parameters; and a Geotechnical Model representing the Ground Model displaying design parameters and predicted performance of the project. Outcrop Confidence is a relative measure of predictability or homogeneity of the structural domain and lithology of rock units over a project site: OC-1 is massive, homogeneous rock units that are vertically and laterally extensive at sites with histories of low tectonic activity; OC-2 rock characteristics are generally predictable, having expected lateral and vertical variability with tectonically produced structural features that tend to be systematic in orientation and spacing; OC-3 rock conditions are extremely variable because of complex depositional or structural history, mass movement, or buried topography. Geotechnical complexity consists of genetic (original formation or deposition); epigenetic (subsequent deformation, diagenesis, or alteration); and surface weathering, erosion, and burial. Quality levels used in subsurface utility engineering (SUE) projects are analogous to geologic investigation levels: QL-D is based on existing information (desktop); QL-C includes field observations (reconnaissance); QL-B includes surface geophysics (limited verification); QL-A includes subsurface investigation (verification). These approaches, when combined, provide a framework for estimating project-scale geologic variability worthy of further consideration.
 
Abstract #2:
Reconnaissance-level terrestrial photogrammetry of rock slopes

Digital photos of slopes have been used widely for many years for reconnaissance-level documentation of conditions for subsequent examination and display. Pairs of photos of the same view from slightly different positions (i.e., stereo pairs) can be used for routine stereoscopic viewing, as well as for making anaglyphs or 3D models with special software (e.g., StereoPhoto Maker or ShapeMetriX3D). Visualization of slope conditions is enhanced with anaglyphs viewed with special glasses (i.e., red-blue) and generic 3D models; however, 3D models made from stereo pairs of digital photos taken with calibrated camera-and-lens combinations and with visible range and vertical-reference features (e.g., a vertical range pole) can be used for making true-scale measurements of positions, distances, and orientation of planar surfaces. Conventional limitations common to all photographic methods apply to 3D models (e.g., slope segments obscured by vegetation, oblique views of inclined elements, parallax distortion). 3D models are more useful than simple photographs for aiding in visualization of slope conditions and understanding causes of failure. Measurements made with the special software can be exported for use in other software applications, such as GIS, precision plotting, and rock-structure analysis programs (e.g., ArcGIS, SigmaPlot, and RockPack). An example from a topographic profile of rock slope over 100 feet high on west-bound Interstate Highway 24 Tennessee located approximately 40 miles west of Chattanooga demonstrate the utility of these technologies.
 
Speaker Biography:
Jeffrey R. Keaton is a Principal Engineering Geologist in AMEC's Los Angeles office. He specializes in quantifying hazardous natural processes for siting and design of all types of facilities in all geologic environments. He has degrees in Geological Engineering, Engineering (Geotechnical), and Geology. He is registered in several states as an Engineer and as a Geologist, he is a Diplomate, Geotechnical Engineering of the Academy of Geo-Professionals, and an Envision Sustainability Professional through the Institute for Sustainable Infrastructure.

He has remained active in professional societies throughout his career, serving as president of AEG, chair of the Engineering Geology Division of GSA, chair of two committees and a section at Transportation Research Board, and chair of the Technical Coordination Council of ASCE's Geo-Institute. Currently, he is chair of IAEG Commission No 1, Engineering Geological Characterisation and Visualisation, and a member of the Executive Committee of the Engineering Accreditation Commission of ABET, Inc.

Contact Information:
Jeffrey R. Keaton, PhD, PE, PG, D.GE, ENV SP, F.ASCE, F.GSA
Principal Engineering Geologist
AMEC
6001 Rickenbacker Road
Los Angeles, CA 90040

Phone: (323) 889-5316
Cell: (323) 215-8454
Email: Jeff.Keaton@amec.com
Website: www.amec.com