New paper by Balaji Paramasivam selected as Editor's Choice

Recent Ph.D. Graduate Balaji Paramasivam’s paper on the influence of prefabricated vertical drains on soil, foundation and structure response in earthquakes is published in the October edition of the Journal of Geotechnical and Geoenvironmental Engineering. It has been selected as the Editor’s Choice.

 Results of centrifuge tests of a structure on liquefiable soil, showing effects of drains (DR) vs. unmitigated (UM) cases.

Results of centrifuge tests of a structure on liquefiable soil, showing effects of drains (DR) vs. unmitigated (UM) cases.


POLLY MURRAY PRESENTS her RESEARCH AT University of auckland, NEW ZEALAND!

Polly Murray, a PhD student at the University of Colorado at Boulder, presented her research on modeling of a ductile reinforced concrete building damaged in the 2016 Kaikoura earthquake to the QuakeCoRE Emerging Researchers Auckland chapter meeting in Auckland, New Zealand.  In an effort to understand the performance of ductile RC buildings during seismic events, a 3D nonlinear model was developed to run dynamic analysis. This research aims to compare predicted strength to observed damage, and assess modifications that could improve performance during future seismic events. Laboratory testing of extracted beam-column joints will offer further insight to the extent of building damage.

Rob Chase Presents on Induced Earthquakes at the Forum for Infrastructure presented by SEG in Oklahoma State University!

On August 24th, Rob Chase presented a poster on Damage Accumulation for a Two-Story Wood Frame Building in Sequences of Induced Earthquakes at the Forum for Infrastructure presented by SEG at Oklahoma State University. Rob’s work is focused on examining how potential seismic loss can change in a light-frame wood structure from multiple low magnitude shaking events.

Sarah's new position: USAID Office of Food for Peace

Sarah Welsh-Huggins has been accepted to the AAAS Science & Technology Policy Fellowship (STPF) program, and awarded a placement at the US Agency for International Development in the Office of Food for Peace. The AAAS STPF program aims to connect science with policy and foster a network of science and engineering leaders who understand government and policymaking, and are prepared to develop and execute solutions to address societal challenges. 

Sarah will complete her fellowship by supporting the Office of Food for Peace as a technical expert in structural engineering. In her role she will manage the development and implementation of civil infrastructure projects that help to reduce food insecurity in vulnerable populations and build resilience in communities facing chronic poverty and recurring crises like drought.   

As an AAAS Science & Technology Policy Fellow, Sarah is among 275 scientists and engineers who will spend a year serving professionally in federal agencies and congressional offices. As highly trained scientists and engineers, the U.S. government benefits from the contributions of STPF fellows, while they learn first-hand about federal policymaking and implementation. The fellowships are operated as part of the American Association for the Advancement of Science (AAAS) mandate to advance science and serve society. The program aims to support evidence-based policymaking by engaging the knowledge and analytical mindset of science and engineering experts, and foster leaders for a strong U.S. science and technology enterprise.

Congratulations, Sarah!

 

Upcoming Webinar

Abbie will be speaking on the EERI Younger Member Committee's webinar on September 17, examining "How induced earthquakes are making us rethink the challenges of earthquake engineering". For more information, or to register, please visit the EERI page

New Paper: Probabilistic Models for Tilt of Shallow-Founded Structures

Zach Bullock's paper, “Probabilistic Models for Residual and Peak Transient Tilt of Mat-Founded Structures on Liquefiable Soils”, has recently been accepted for publication by ASCE's Journal of Geotechnical and Geeoenvironmental Engineering.  The paper is co-authored by Zana Karimi, Shideh Dashti, Abbie Liel, Kevin Franke and Keith Porter. This paper is a companion to Zach's probabilistic models for settlement of buildings on liquefiable soils, available online from Geotechnique

We also provide spreadsheets for users to easily implement these models. 

 Sensitivity of residual tilt to properties of the structure for three representative ground motions and intensity levels in numerical analyses.

Sensitivity of residual tilt to properties of the structure for three representative ground motions and intensity levels in numerical analyses.

Congratulations to Balaji Paramasivam

Balaji successfully defended his doctoral dissertation entitled: "Influence of traditional and innovative liquefaction mitigation strategies on the performance fo soil-structure systems, considering soil heterogeneity". Congratulaions, Balaji! We will post his dissertation here when the final version is available. 

Presentations and Papers at 11th National Conference in Earthquake Engineering

Current and past members of our group were well-represented at the 11NCEE, held in LA in June 2018. 

 Samantha Grey, M.S. student; D. Jared DeBock, Ph.D., 2013, now Assistant Professor at Chico State; Siamak Sattar, Ph.D. 2012, now Research Structural Engineer at the National Earthquake Hazards Reduction Program at NIST; Abbie Robert Chase, Ph.D. Candidate; Yolanda LIn, M.S. graduate & recent Ph.D. from Cornell University; and Dustin Cook Ph.D. Candidate

Samantha Grey, M.S. student; D. Jared DeBock, Ph.D., 2013, now Assistant Professor at Chico State; Siamak Sattar, Ph.D. 2012, now Research Structural Engineer at the National Earthquake Hazards Reduction Program at NIST; Abbie Robert Chase, Ph.D. Candidate; Yolanda LIn, M.S. graduate & recent Ph.D. from Cornell University; and Dustin Cook Ph.D. Candidate

 Robert Chase, at his presentation at 11NCEE

Robert Chase, at his presentation at 11NCEE

SEISMIC PERFORMANCE ASSESSMENT OF HSR BRIDGES THROUGH STRUCTURAL SIMULATION AND TESTING (work of Mohammad Salehi and others) 

IMG_7081.JPG

 

QUANTIFYING IMPROVEMENTS IN SEISMIC PERFORMANCE POSSIBLE THROUGH RETROFIT OF RC FRAMES (work of Cody Harrington and others) 

TORSIONAL IRREGULARITY AS A COLLAPSE INDICATOR FOR OLDER CONCRETE BUILDINGS (work of Travis Marcilla and others) 

We were also happy to support the efforts of the CU undergraduate seismic design team. 

 CU undergraduate seismic design team. Excellent work! 

CU undergraduate seismic design team. Excellent work! 

 A group of us celebrating CU's strong presence at the conference. Go Buffs!

A group of us celebrating CU's strong presence at the conference. Go Buffs!

 

 

Predicting Liquefaction-Induced Settlement and Tilt of Buildings

Zach Bullock has produced two models relevant to liquefaction consequences. One predicts settlements of shallow-founded structures, considering soil, foundation and structural properties.  The other predicts tilt (or permanent rotation) of mat-founded structures. Both models are fully probabilistic. 

Check out these resources to get started: 

1) the manuscript describing the settlement model ("A physics-informed semi-empirical probabilistic model for the settlement of shallow-founded structures on liquefiable ground"), published in Geotechnique 

2)  the manuscript describing the tilt model ("Probabilistic Models for Residual and Peak Transient Tilt of Mat-Founded Structures on Liquefiable Soils"), recently accepted by the Journal of Geotechnical and Geoenvironmental Engineering

3) a spreadsheet for implementing both settlement and tilt models. 

Details about the numerical simulations of soil-foundation-structure interaction on liquefiable ground that partially underlay the models is in a paper available from Soil Dynamics and Earthquake Engineering. 

 

Remembering a mentor

I have had amazing mentors in my life. One of the most influential - Professor David Billington.

Check out this story (https://www.princeton.edu/news/2018/04/05/david-billington-scholar-structural-art-dies-90) about his legacy. 

Presentations at Structures Congress

Our group made a number of presentations at the 2018 Structures Congress in Fort Worth, Texas. 

These include: Jakub Valigura "Risk-Based Seismic Loss Assessment for RC Bridges, Accounting for Various Repair Strategies", Mohammad Salehi "Computational and Experimental Seismic Performance Evaluation of Hybrid Sliding-Rocking Bridges", Robert Chase "Damage Accumulation in Sequences of Induced Earthquakes", and Abbie Liel "Evaluation of ASCE 41 for Seismic Retrofit Design" and "Linking Community Participation to Structural Performance in Post Earthquake Housing Reconstruction Programs". 

 Ph.D. Student Robert Chase, making his presentation. 

Ph.D. Student Robert Chase, making his presentation. 

 Ph.D. Student Jakub Valigura, at Structures Congress 2018

Ph.D. Student Jakub Valigura, at Structures Congress 2018

Congratulations, Jenny!

PhD student Jenny Ramirez was awarded the Graduate Teacher Program Award for Excellence in Academic Leadership. This award recognized Jenny's hard work in the Graduate Teacher Program (GTP): "Jenny’s work as Lead for the GTP this year was truly outstanding. Through her own hard work and initiative, she has vastly increased interest and participation in GTP programs by CEAE grad students. She performed an astounding twenty-four Videotape Teaching Consultations for her fellow TAs (Leads are only required to do two, and each VTC requires a good deal of time and energy). Equally impressively, at her own initiative Jenny personally went through the GTP workshop records for several hundred CEAE grad students, figured out which students had done at least five workshops, and then she contacted those students and encouraged them to finish their GTP Certificate in College Teaching. As a result, we’ve seen an increase in the number of grad students from your department at workshops and engaged in the certification process, which not only improves teaching, but also helps them on the job market.  Jenny also created a handbook for incoming and continuing graduate students to help them navigate the graduate program. Throughout the year she was in constant contact with our Lead Coordinators at GTP, figuring out what more she could do, and how she could do it better. We at GTP are so impressed with what she’s been able to do, and so grateful for all her hard work. "

Congratulations, Jenny! Thanks for all that you do! 

 Jenny Ramirez, at the award ceremony. 

Jenny Ramirez, at the award ceremony. 

Graduation & Abbie awarded CEAE Research Development Award

Congratulations to the class of 2018! At the graduation ceremonies, Abbie was also awarded the Civil, Environmental and Architectural Engineering Research Development Award, recognizing the efforts of so many in our group. 

 Samantha Grey, M.S. graduate! Great work Sam! 

Samantha Grey, M.S. graduate! Great work Sam! 

 Congratulations to Dr. Erin Arneson! I was delighted to be a part of your PhD journey.       

Congratulations to Dr. Erin Arneson! I was delighted to be a part of your PhD journey. 

 

 

 Tyler Davis, BS/MS Graduate. Congratulations, Tyler! 

Tyler Davis, BS/MS Graduate. Congratulations, Tyler! 

New papers on liquefaction consequences and mitigation

Our group has authored three papers on liquefaction consequences and mitigation that have recently been published. These are: 

Bullock, Zach, Zana Karimi, Shideh Dashti, Keith Porter, Abbie Liel and Kevin Franke, “A Physics-Informed Semi-Empirical Probabilistic Model for the Settlement of Shallow Founded Structures on Liquefiable Ground”, Geotechnique, In Press, 2018.  We will also provide a spreadsheet that assists in doing the calculations for this model. Check back here soon for updates. 

Paramasivam, Balaji, Shideh Dashti and Abbie Liel, “Influence of Prefabricated Vertical Drains on the Seismic Performance of Structures Founded on Liquefiable Soils”, ASCE Journal of Geotechnical and Geeoenvironmental Engineering, In Press, 2018.

Olarte, Juan, Shideh Dashti and Abbie B. Liel, “Effects of Drainage Control on Densification as a Liquefaction Mitigation Technique”, Soil Dynamics and Earthquake Engineering, 110, 212-231, 2018.

Thanks Zach, Balaji and Juan for these excellent works of scholarship! 

Casie presented at the Construction Research Congress

 

Read More

Congratulations to Jenny Ramirez

 

Read More

Congratulations to Amy Javernick-Will!

 

Read More