Jeffrey R Keaton Principal Engineering Geologist Amec Foster Wheeler, Los Angeles, USA

Transcription

1 Association of Environmental and Engineering Geologists AEG Inland Empire Chapter Newsletter of the Southern California Section December 2015 Vol.12 No. 3 December 2015 Meeting Announcement Earthquake Ground Motion for Design of Hoover Dam Bypass Bridge (US Highway 93) Jeffrey R Keaton Principal Engineering Geologist Amec Foster Wheeler, Los Angeles, USA Wednesday, December 9 th, 2015 Location: Pinnacle Peak Steakhouse, Colton, CA See speaker & meeting details on pages 3-4 RSVP to aeginland@gmail.com by 5:00pm, Monday December 7, INSIDE Pages: 2 Chair Message 3-4 Meeting Information 5-7 Other Meetings & Announcements

2 AEG Inland Empire Chapter - December 2015 Chair s Message Another nice group for our November 12th meeting at Pinnacle Peak. The AEG-Inland Empire Chapter would like to extend its gratitude to Dr. Norman Meek for his presentation, How (In) Effective is the Headward Erosion Process? Part of Dr. Meek s lecture involved his research into numerous surficial and physical geology textbooks and the discussion or limited discussion of erosion processes, therein. I have to admit, Friday morning at work, I checked both of the books I used in school, Physical Geology by Leet, Judson & Kauffman and Surficial Geology Building with the Earth by Costa and Baker, and found them very limited in the discussion of the various erosional processes described by Dr. Meek. He also discussed the ideas of stream capture vs. ponding and overflow as it relates to the current alignment of the Colorado River. Very compelling. His presentation was topped off with a series of videos, shot in time lapse photography, clearly illustrating the major points he made in his talk. A picture (or video in this case) is worth a thousand words. In last month s Chair s Message, I moved outside of my geologic boundaries and ventured into the area of land surveying. The idea described to me from a field supervisor of our County Survey Division was that because of the San Andreas fault in southern California, the survey datum or baseline was constantly changing due to the movements of the Pacific plate. Along these same lines but on a more local and severe level, our Development Review section received an inquiry from one of the cities on the Palos Verdes Peninsula about property on active landslides. A property owner with property of one of the active landslides on the peninsula wanted to sell their property and hired a surveyor to define the property boundaries. The surveyor s question, which was forwarded to the County through the city, was should his benchmark be outside of the landslide, or should he determine where the property boundaries would be based on where they are currently located with respect the property. If he uses a benchmark outside of the active landslide then, a portion of the physical property would be located on someone else s lot. The bottom line is the current property lines are not in the locations as originally surveyed. I don t know if there is an established precedent but we re (the Development Review section) thinking this will require input from someone s counsel. One last note. I m going to cross boundaries here and mention the November 5th Inland Geological Society meeting. The speaker was Laurie Racca of the State Board for Professional Engineers, Land Surveyors, and Geologists (BPELSG). She provided an excellent overview on the history of the Board but, more importantly, changes in the regulations that affect geologists. If you re like me, I haven t given much thought to the Board since I received my PG and CEG registrations and, of course, every 2 years, when I pay my registration fees. You need to go to the BPELSG website atwww.bpelsg.ca.gov to review the changes in regulations that affect geologists, particularly those of you who are working independently or for private firms. One word contracts. We look forward to meeting and seeing you at this month s talk titled Earthquake Ground Motion for Design of the Hoover Dam Bypass Bridge by Dr. Jeff Keaton, Principle Engineering Geologist with AMEC Foster Wheeler. If you don t know Dr. Keaton, I m sure you ve seen him at several of our meetings and functions and will recognize him instantly. Greg Johnson, Chair AEG Inland Empire Chapter Note from the Editor SPONSOR! SPONSOR! SPONSOR! We are looking for companies to be annual sponsors so more students can get involved by attending at a lower cost. So help the students out while you market your business. Students!!! If you attend the meeting, you can me your resume after the meeting and it will be included in the next months newsletter. Members, if you have any announcements, please me the information by the 25 th of the month. Otherwise the information will be put into the following month s newsletter. Thank you, and I look forward to seeing you at the next event. James Burns AEG-IE Newsletter Editor AEG Inland Empire Chapter News December 2015 Page 2

3 Jeffrey R. Keaton PhD, PE, PG, D.GE, ENV SP, F.ASCE, F.GSA, Principle Engineering Geologist Amec Foster Wheeler, Americas -Environment & Infrastructure Earthquake Ground Motion for Design of Hoover Dam Bypass Bridge (US Highway 93) ABSTRACT The Hoover Dam Bypass Project is a 3.5-mile corridor on U.S. Highway 93 in Clark County, Nevada, and Mohave County, Arizona, crossing the Colorado River approximately 1,500 feet downstream of Hoover Dam. The proposed bridge will be 1,896 feet long and 88 feet wide. The main span will be a Composite Concrete Deck Arch Bridge with an overall length of 1,090 feet. Five approach spans on the Nevada side and two on the Arizona side range in length from 100 to 120 feet. Seventeen faults within 100 miles of the site were considered to be active. Maximum earthquake magnitudes were determined for each active fault, and peak horizontal accelerations were estimated using three ground-motion attenuation relationships. The Colorado River bridge was designed on the basis of a nonlinear dynamic analysis using three-component seismograms at each abutment. The approach bridges were designed on the basis of a response spectrum analysis. The river bridge will be a flexible structure with a fundamental period longer than 1 s. A 1-s spectral acceleration of g was selected as the target ground motion on which to anchor design earthquakes and response spectra. The target 1-s spectral acceleration would be produced by a moment magnitude earthquake of 6.2 on the Mead Slope fault at a hypocentral distance of 16 km, or by a moment magnitude earthquake of 7.0 on the California Wash fault at a hypocentral distance of 36 km. Acceleration response spectra for both design earthquakes were calculated using an appropriate attenuation relationship. The smaller magnitude earthquake produced the maximum high-frequency motion, whereas the larger magnitude earthquake produced the maximum low-frequency motion. The recommended design response spectrum for the river bridge was the maximum of the two motions. A Composite Source Model was used to produce synthetic, three-component seismograms at each abutment for nonlinear dynamic analysis of the river bridge. Input parameters for the Composite Source Model included specific geographic fault location, parameters pertaining to the physics of fault rupture (length, width, average displacement, rake and rupture velocity), and seismological parameters of the source (seismic moment and stress drop) and site area (Green s functions). The acceleration time history records generated with the Composite Source Model were adjusted to bring their acceleration response spectra into close agreement with the design response spectrum. The synthetic seismograms have realistic appearances in both amplitude of motion and duration of strong shaking. The velocity seismogram for the magnitude 6.2 earthquake contains a single, prominent spike representing a fault fling effect that has been observed in near-field earthquakes. SPEAKER BIOGRAPHY Jeffrey R. Keaton 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. Keaton has been employed by consulting firms for over 45 years, and in Amec Foster Wheeler s Los Angeles office of since July 2005 where he is a Principal Engineering Geologist. He is registered in several states as an Engineer and as a Geologist; he holds the Envision Sustainability Professional (ENV SP) credential from the Institute for Sustainable Infrastructure and is a Diplomate in Geotechnical Engineering of the Academy of Geo-Professionals. He has remained active in professional societies throughout his career. He currently serves the International Association for Engineering Geology and the Environment as Vice President for North America, the American Society of Civil Engineers as a member of the Committee on Sustainability and as the chair of its Strategic Communications Subcommittee. He also is chair of the Sustainability in Geotechnical Engineering Committee of ASCE s Geo-Institute, a member of the Steering Committee of the Geotechnical Extreme Event Reconnaissance (GEER) Association, and an ex officio member of the Executive Committee of ABET s Engineering Accreditation Commission. He is a past president of the Association of Environmental & Engineering Geologists, past chair of the Transportation Research Board Section on Geology and Properties of Earth Materials, the Exploration and Classification of Earth Materials Committee, and the Engineering Geology Committee, and past chair of the Environmental & Engineering Geology Division of the Geological Society of America. AEG Inland Empire Chapter News December 2015 Page 3

4 AEG-IE Chapter Officers Chair Greg Johnson LA County DPW (626) Vice Chair Jeff Fitzsimmons Lahontan RWQCB (951) AEG-IE DECEMBER MEETING DETAILS Date/Time Wednesday, December 9, Social hour 5:30-6:30 Dinner 6:30-7:15 Announcements 7:15-7:30 Talk and Q&A 7:30-8:30 Location Pinnacle Peak 2533 La Cadena Drive South Colton, CA Vice Chair South Andrew Robinson University California Riverside (951) Treasurer Mark Doerschlag Peak Group Cost RSVP $25 with RSVP $10 per student with RSVP and proof of valid student ID $30 for walk-ins without RSVP Deadline is COB Monday, December 7, 2015 Individuals who RSVP but do not attend may be charged if the final attendance does not meet the restaurant guarantee. Secretary Shaun Wilkins Petra Geosciences, Inc. (657) Past Chairs; Greg Johnson, 2015 David Gaddie, 2014; Douglas Johnston, 2013; Debbie Kunath, 2012; Frank Jordan, 2005, 2011; Douglass Johnston, 2010; Kerry Cato, 2009 Newsletter Editor James Burns (760) The AEG Inland Empire Chapter Newsletter is a monthly publication of the Inland Empire Chapter of the Southern California Section, Association of Environmental and Engineering Geologists. For more information visit the Chapter website: nlandempire. DIRECTIONS TO THE MEETING LOCATION Directions: From I-215 Heading South: 1. Exit Barton Road and merge onto La Crosse Ave 2. Turn Right onto Barton Road 3. Turn slight Left onto La Cadena Drive South 4. Destination on right. (2533 La Cadena Drive South). Directions: From I-215 Heading North: 1. Exit South Iowa Avenue. 2. Turn Right onto South Iowa Avenue 3. Continue onto La Cadena Drive South 4. Make a U-Turn at West La Loma Street 5. Destination on right. (2533 La Cadena Drive South). Submittals: Deadline, 25 th of the month. Employment notices, job position announcements, and advertisements can be posted for a minimal fee. Newsletter circulation exceeds 300 people in greater inland areas of Southern California, and elsewhere. Address changes: aeginland@gmail.com AEG Inland Empire Chapter News December 2015 Page 4

5 ANNOUNCEMENTS & OTHER MEETINGS OTHER MEETINGS AEG-Southern California Section: December 2015 Meeting TBD. For more information visit: AEG-Inland Empire Section: December 9, 2015 (Wednesday). Earthquake Ground Motion for Design of Hoover Dam Bypass Bridge (US Highway 93) Speaker: Jeffrey R Keaton PhD, PE, PG, D.GE, ENV SP, F.ASCE, F.GSA, of Amec Foster Wheeler For more information visit: ASCE: (Orange County Branch). December 10, 2015 (Thursday). Branch Luncheon Unmanned Aerial Vehicles (UAVs) Ms. Jackie L Patterson. For more info visit: ASCE: (San Bernardino-Riverside County Branch). December 2015 Meeting TBD. For more info visit: ASCE: (San Diego County Branch). December 2015 Meeting TBD. For more info visit: EERI: (San Diego). TBD. For more info, visit: GRA: December 10, 2015 (Thursday). Field Trip & Holiday Island White -THUMS Islands. See Website for Meetings. For more info, visit IGS: December 2, 2015 (Wednesday) A Poor Judgement Can Lead to Better Judgment Speaker: Ms. Marina West, PG, General Manager, Bighorn-Desert View Water Agency. For more info visit: LA Basin: January Meeting TBD. For more info visit: SCGS: December 7, 2015 (Monday). Topic: SCGS Annual Holiday Party & Raffle Speaker: YOU! For more info visit: SME: December Meeting TBD. For more info visit: SDAG: December 9, 2015 San Diego Natural History Museum. Topic: TBD Speaker: Tom Deméré. Annual Field Trip, 2016: TBD For more info visit: AEG Inland Empire Chapter News December 2015 Page 5

6 CONGRATULATIONS NEW OFFICERS! The ballots have been counted and these are your new officers for Chair Greg Johnson LA County DPW Vice Chair, North Jeff Fitzsimmons Lahontan RWQCB Vice Chair, South Andrew Robinson UC Riverside Treasurer Mark Doerschlag Peak Group Secretary Shaun Wilkins Petra Geosciences AEG MEMBER BENEFITS Conferences - You will find value at both Annual Meetings and Specialty Conferences and in the technical knowledge and continuing education you receive at these meetings. (More Info) Networking Opportunities - With over 3000 members, AEG provides you with access to a wide network of Environmental and Engineering geology professionals at both our local section meetings and at national conferences. (More Info) Publications - AEG News, the Environmental & Engineering Geoscience Journal, and the AEG Insider contain relevant geoscientific information, updates on AEG activities, and engaging scientific interest stories. (AEG News)(AEG Insider) With benefits like these, of course you want to be part of AEG! We encourage you to spread the word talk to your co-workers, classmates and friends about AEG and all it has to offer. REMEMBER: Student Membership is FREE! Graduating student receive their first year of full membership for FREE as our Graduation Gift to you (Contact us at aeg@aegweb.org to receive your gift) If you have thank you! Full members receive discounted registration for Annual Meetings and Specialty Conferences. If you have any questions regarding your membership status or would like to join, please call one of our officers. AEG Inland Empire Chapter News December 2015 Page 6

7 AEG_Inland Empire Chapter Monthly Speaker Schedule Meeting Date Guest Speaker Title of Presentation Wednesday, October 21, 2015 Dr. Jonathan C. Matti - Geologist, U.S. Geological Survey The San Andreas Fault system in the Inland Empire region: What is known and what remains to be known Thursday, November 12, 2015 Wednesday, December 09, 2015 Dr. Norman Meek - Chair of the Department of Geography and Environmental Studies, CSUSB Dr. Jeff Keaton - Principal Engineering Geologist, AMEC Foster Wheeler, Los Angeles, CA Wednesday, January 20, 2016 Dr. Peter Robinson - Technical/Management Advisor Gregg Drilling and Testing, Inc. Signal Hill, California Wednesday, February 17, 2016 Wednesday, March 16, 2016 Dr. Sally McGill - Chair of the Department of Geologic Sciences, CSUSB Dr. David Oglesby - Chair of the Department of Earth Sciences, UCR How (In)Effective is the Headward Erosion Process Earthquake Ground Motion for Design of Hoover Dam Bypass Bridge An Introduction to the CPT for geotechnical and geoenvironmental applications Distribution of fault slip across the Pacific-North America plate boundary in southern California: Recent results from geologic and geodetic studies Dynamic models of an earthquake and tsunami offshore Ventura, California April 2016 INLAND GEOLOGICAL SOCIETIES-JOINT MEETING: AEG-IE, IGS, SME, CSUSB TBA May 2016 Short Course TBA June 2016 Dr. John Izbicki - Geologist, U.S. Geological Survey TBA AEG Inland Empire Chapter News December 2015 Page 7