AEG June Meeting: Tuesday, October 27
Please join us on Tuesday, October 27, 2020 for an AEG Sacto virtual monthly meeting! We will be hosting Renmin Pretell from UC Davis, who will be giving a presentation titled Liquefaction and Cyclic Softening at Balboa Boulevard During the 1994 Northridge Earthquake
You can join the Zoom meeting by clicking HERE!
SPEAKER BIO:
Renmin earned his B.Sc. in civil engineering from the National University of Engineering (UNI) in Peru (2012). From 2013 to 2017, Renmin worked for Golder Associates in the Lima (Peru) and Denver (CO) offices, mainly focused on geotechnics applied to mining projects. Renmin joined the University of California, Davis, in 2017 received his M.Sc. in 2019, and is currently pursuing his Ph.D. degree. Renmin’s research interests include liquefaction, site response, ground motions, and geostatistics..
SPEAKER ABSTRACT:
The seismic performance of the Balboa Blvd. during the 1994 MW 6.7 Northridge Earthquake was examined through nonlinear deformation analyses (NDAs) using stateoftheart tools to (1) evaluate the accuracy of the adopted modeling protocols and engineering procedures to capture ground deformation patterns and displacement magnitudes; and (2) investigate the failure mechanisms and key factors leading to ground deformations at this site. 1D liquefaction vulnerability indexes (LVIs) and permanent displacements using Newmark sliding block analyses were also estimated and compared against ground deformations observed after the earthquake. The geotechnical characterization of Balboa Blvd. was assessed based on field and laboratory data obtained from two investigation campaigns. Transitional probability geostatistics were used to develop stratigraphic models that capture the heterogeneity and the spatial variability patterns of sandlike and claylike soils present at this site. The stratigraphic models were implemented in the finite different software FLAC and the behavior of sandlike and claylike soils simulated using the PM4Sand v3.1 and PM4Silt v1.0 constitutive models (Boulanger and Ziotopoulou 2017, 2018). A series of sensitivity analyses were performed to address uncertainties associated to the spatial variability of soils, input ground motions, the Ic cutoff parameter to differentiate between sandlike and claylike soils, relative density (DR) of sandlike soils, and undrained strength (su) of claylike soils, amongst others. Results from NDAs suggest that a compounded effect of both liquefaction of sandlike soils and cyclic softening of claylike soils led to the excessive ground deformations at Balboa Blvd. This study sheds light on the importance of using appropriate engineering procedures and numerical modeling protocols in the prediction of deformation patterns, the selection of key input parameters, as well as the applicability of LVIs in complex sites.
AGENDA:
- Social Hour/Waiting Room Opens – 5:30 – 6:00 p.m.
- Announcements & Introductions: 6:00-6:15 pm
- Presentation: 6:15 – 7:15 pm
- Q&A: 7:15 – 7:30 pm
Feel free to BYOB!
MEETING COSTS AND RSVP:
No Charge! Virtual Meeting
2020 Calendar of Events
| Date | Event |
| January 21 | AEG January Meeting Speaker: Mitchell Swanson Talk: Lower American and Sacramento Rivers Geomorphology Applications for Bank Erosion and Levee Stability and Ecosystem Restoration Location: Aviators, Sacramento Registration: HERE! |
| February 25 | AEG February Meeting: Jahn’s Lecturer Series Speaker: Scott Lidnvall Talk: Characterizing Fault Displacement Hazards: Significant Progress and Significant Uncertainties Location: Aviators, Sacramento Registration: HERE! |
| February 28 | Taber Ranch Foundation Drill Class Annual Taber Ranch one day course for undergraduate students. |
| March 24 (POSTPONED) | AEG March Meeting Speaker: Jim Bailey Talk: Migrating Mud Pot – Emergency Responses to Protect Critical Transportation Infrastructure (POSTPONED) |
| April 3 | Undergraduate and Graduate Scholarships Deadline Deadline: Friday, April 12th |
| April 21 (CANCELLED) | Annual Student Night Theme: Student poster presentations, student-professional interaction and networking, AEG presentation of scholarship recipients Location: Old Spaghetti Factory, Sacramento |
| May 19 (POSTPONED) | AEG May Meeting Speaker: Alex Morelan Talk: Ridgecrest Earthquakes Location: Aviators, Sacramento |
| June 23 | AEG June Meeting Speaker: Augie Smarkel Talk: Slope Stability Case History Project in the AP Zone Along the Hayward Fault Location: Zoom Virtual Meeting |
| July | No July Meeting |
| August 23 | No August Meeting |
| September 24 | No September Meeting: Annual Meeting |
| October 27 | AEG October Meeting Speaker: Renmin Pretell Talk: Liquefaction and Cyclic Softening at Balboa Boulevard During the 1994 Northridge Earthquake Location: Zoom Virtual Meeting |
| November 17 | Joint AEG/CalGeo Emerging Professionals November Meeting Speaker: Ross Boulanger Talk: Liquifaction Location: TBD |
| December 14 | Annual Joint GRA/AEG Holiday Meeting Speaker: TBD Talk: TBD Location: Aviators, Sacramento |
