Location

Chicago, Illinois

Date

02 May 2013, 7:00 pm - 8:30 pm

Abstract

The Panama Canal Third Set of Locks Project is being constructed within a geologically diverse setting. Of particular interest is the upper chamber of the Pacific Locks Complex, which is 400 meters long and founded on basalt bedrock but crosses a 90 m wide fault zone. After completing the excavation to foundation grade, the fault zone was mapped and drilling investigations, in-situ geomechanical testing, and laboratory testing were performed. The fault zone contains highly fractured, faulted, and brecciated rock types that were grouped into two geomechanical classes, Class I and Class II. Given the extent of the fault zone and variability of the geologic conditions within the fault zone, the foundation analysis was coordinated with the structural design of the lock walls to take into account deformation and sliding stability to meet the design and performance requirements. Two-dimensional (2D) and three-dimensional (3D) finite element analyses were performed using Phase2 and Abaqus 3D to estimate foundation settlements and evaluate the stresses within the lock walls. In addition, sensitivity analyses were performed using Abaqus 2D to evaluate bearing capacity and optimize concrete reinforcement. A second less extensive fault zone was later encountered, and based on the experience gained in developing the mitigation measures for this fault zone, it was determined that similar mitigation measures were applicable.

Department(s)

Civil, Architectural and Environmental Engineering

Meeting Name

7th Conference of the International Conference on Case Histories in Geotechnical Engineering

Publisher

Missouri University of Science and Technology

Document Version

Final Version

Rights

© 2013 Missouri University of Science and Technology, All rights reserved.

Creative Commons Licensing

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Apr 29th, 12:00 AM May 4th, 12:00 AM

Foundation and Structural Design of Lock Walls Founded on a Fault Zone

Chicago, Illinois

The Panama Canal Third Set of Locks Project is being constructed within a geologically diverse setting. Of particular interest is the upper chamber of the Pacific Locks Complex, which is 400 meters long and founded on basalt bedrock but crosses a 90 m wide fault zone. After completing the excavation to foundation grade, the fault zone was mapped and drilling investigations, in-situ geomechanical testing, and laboratory testing were performed. The fault zone contains highly fractured, faulted, and brecciated rock types that were grouped into two geomechanical classes, Class I and Class II. Given the extent of the fault zone and variability of the geologic conditions within the fault zone, the foundation analysis was coordinated with the structural design of the lock walls to take into account deformation and sliding stability to meet the design and performance requirements. Two-dimensional (2D) and three-dimensional (3D) finite element analyses were performed using Phase2 and Abaqus 3D to estimate foundation settlements and evaluate the stresses within the lock walls. In addition, sensitivity analyses were performed using Abaqus 2D to evaluate bearing capacity and optimize concrete reinforcement. A second less extensive fault zone was later encountered, and based on the experience gained in developing the mitigation measures for this fault zone, it was determined that similar mitigation measures were applicable.