Influence of Traditional and Innovative Liquefaction Mitigation Strategies on the Performanc of Soil-structure Systems, Considering Soil Heterogeneity
出版項
2018
說明
1 online resource (427 pages)
文字
text
無媒介
computer
成冊
online resource
附註
Source: Dissertation Abstracts International, Volume: 80-02(E), Section: B
Advisers: Shideh Dashti; Abbie B. Liel
Thesis (Ph.D.)--University of Colorado at Boulder, 2018
Includes bibliographical references
Liquefaction mitigation techniques are often used in the field to alleviate liquefaction hazard to the built environment. However, the current practice of designing mitigation techniques ignores the presence of buildings, and depends solely on satisfying the settlement criteria, and constructability. This design practice is due to lack of understanding of the influence of different mitigation strategies on the performance of soil-foundation-structure systems
In this dissertation, centrifuge experiments were designed and conducted to investigate soil-mitigation-foundation-structure systems, considering two potentially inelastic structures (3- and 9-story) placed on a layered liquefiable deposit (with and without a silt cap), with three different mitigation strategies: 1) enhanced drainage through prefabricated vertical drains (PVDs); 2) shear reinforcement using in-ground structural walls (SWs); and 3) enhanced drainage and damping, and shear reinforcement provided by an in-ground gravel-rubber panel wall system
The first set of test results show that PVDs and SWs reduced total foundation settlement compared to the unmitigated case. However, they amplified accelerations on the foundations, which could increase flexural deformations and P-Delta effects, with potentially adverse effects on foundation tilt (particularly for the taller, heavier, more deeply embedded, and weaker 9-story structure). The presence of soil interlayering (due to a silt cap) affected the overall response of unmitigated and PVD-mitigated structures, particularly impacting foundation tilt
Based on the insights gained from the tests with traditional mitigation techniques, we designed and tested a new mitigation strategy for shallow-founded structures: an in-ground gravel-rubber panel wall (GR) system. This system aims to reduce building settlements and tilts, while isolating the structure from the larger acceleration demands expected in mitigated ground. Test results showed that the GRs could be beneficial, roughly satisfying design objectives for the 3-story structure, but amplified tilt on the 9-story structure. Therefore, additional design considerations and shear reinforcement are required in the panel walls to improve total system response
The results presented in this dissertation point to the importance of considering the structure's dynamic and geometric properties, force-deformation behavior, soil interlayering, and the possible increase in shaking intensity level due to different mitigation strategies, when designing traditional or innovative techniques to mitigate consequences of liquefaction
Electronic reproduction. Ann Arbor, Mich. : ProQuest, 2019
