• About Us
  • What's New
  • People
  • Publications
  • Resources for Students
  • Educational Materials
  • SOFTWARE & DATA
Menu

Liel Research Group

Civil, Environmental and Architectural Engineering; University of Colorado Boulder
  • About Us
  • What's New
  • People
  • Publications
  • Resources for Students
  • Educational Materials
  • SOFTWARE & DATA

Our group does research in structural engineering, focusing on the impacts of extreme events on structures and communities, at the University of Colorado Boulder. Please explore this site to see what we are working on, find recent publications and contact us. 

temp.png

New publication: EFFECTS OF DRAINAGE CONTROL ON DENSIFICATION AS A LIQUEFACTION MITIGATION TECHNIQUE

March 19, 2018

Juan Olarte's paper "Effects of Drainage Control on Densification as a Liquefaction Mitigation Technique" will be published by Soil Dynamics and Earthquake Engineering. Please email me if you would like a copy before it is available here. 

Abstract: 

Ground densification is among the most popular techniques for liquefaction mitigation employed in practice. Yet, the effects of densification, especially in combination with strategies that enhance or inhibit drainage to or from the densified area, on the performance of the soil-foundation-structure system are not well understood. This paper describes dynamic centrifuge experiments to evaluate these effects, considering 3- and 9-story, model moment-resisting frame structures, founded on a stiff mat and a 1-story basement, respectively, on a layered liquefiable soil deposit. The experiments compared structures mitigated with densification alone, and mitigated with a combination of densification and either prefabricated vertical drains (enhancing drainage) or a flexible impermeable latex barrier (inhibiting drainage) around the densified area. Ground densification tended to reduce the foundation settlement, although not to acceptable levels (based on limiting values typically considered in design and performance assessment, and discussed in this paper), but amplified the drift and acceleration demands on the superstructure. The addition of a flexible impermeable barrier around the densified area did not have a notable influence on foundation settlement. However, it increased the excess pore pressures under the edges of the 3-story structure by inhibiting outward flow, amplifying its foundation rotation compared to the case with densification alone. In the case of the heavier and deeper, 9-story structure, adding a barrier around the densified zone restricted the locally inward flow from the adjacent loose soil. This helped reduce net pore pressures under the edges of the structure after strong shaking, foundation rotation, and seismic demand on the superstructure. Enhancing drainage around the densified zone, on the other hand, notably reduced permanent foundation settlement and rotation during all motions nearly to acceptable limits, but amplified accelerations, imposing additional seismic demands on the structure, which could lead to damage if not considered in design. These results demonstrate the importance of considering the structure’s dynamic properties and force-deformation behavior, foundation and ground motion properties, and soil-structure interaction when planning the geometry of ground densification and drainage.

← Recent talks New paper published on Settlement on Liquefiable ground →

UPDATES 

Featured
Dec 3, 2021
Blogs on safe housing
Dec 3, 2021
Dec 3, 2021
IMG_5599.jpg
Dec 3, 2021
Research group accomplishments
Dec 3, 2021
Dec 3, 2021
IMG_1011.jpg
Nov 6, 2020
Presentation at NCSEA Summit
Nov 6, 2020
Nov 6, 2020
Oct 14, 2020
Our work on Functional Recovery
Oct 14, 2020
Oct 14, 2020
IMG_9221.jpg
Oct 14, 2020
Research Group Hike
Oct 14, 2020
Oct 14, 2020
May 28, 2020
Congratulations, Lianne!
May 28, 2020
May 28, 2020
May 28, 2020
Congratulations, Casie!
May 28, 2020
May 28, 2020
sustainability-12-03837-g001-550.jpg
May 14, 2020
Paper: Perceptions of Post-Disaster Housing Safety in Future Typhoons and Earthquakes
May 14, 2020
May 14, 2020
Picture1.png
May 2, 2020
Recent field work
May 2, 2020
May 2, 2020
DSC_0467.jpg
May 2, 2020
Congratulations to Dr. Siamak Sattar
May 2, 2020
May 2, 2020

Powered by Squarespace