Location
St. Louis, Missouri
Date
03 Jun 1993, 10:30 am - 12:30 pm
Abstract
Construction of a 21-foot wide, 28-foot deep braced excavation in Detroit soft clays has been completed. In order to protect an existing 50-year old tunnel adjacent to the excavation, a semi-rigid, tangent wall earth retention system was constructed to minimize the soil movements. The tangent wall was formed by 118 drilled piers with 42-inch in diameter and 41-foot long. The maximum soil lateral and vertical movements adjacent to the excavation were controlled below a magnitude of 2.0 inches, while bottom of the excavation experienced about 3 inches of heave. This paper presents the design considerations and construction performance of the retention system based on geotechnical instrumentation data. Prediction of maximum soil lateral movement based on a finite element analysis and a semi-empirical method conformed well with field measurements. Experience learned from the design and construction will be valuable for future construction of braced excavation systems in similar soil conditions.
Department(s)
Civil, Architectural and Environmental Engineering
Meeting Name
3rd Conference of the International Conference on Case Histories in Geotechnical Engineering
Publisher
University of Missouri--Rolla
Document Version
Final Version
Rights
© 1993 University of Missouri--Rolla, All rights reserved.
Creative Commons Licensing
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
Recommended Citation
Lien, B. H.; Abedi, H.; Ramos, J. A.; and Porter, T. G., "Performance of a Semi-Rigid Braced Excavation in Soft Clay" (1993). International Conference on Case Histories in Geotechnical Engineering. 22.
https://scholarsmine.mst.edu/icchge/3icchge/3icchge-session05/22
Performance of a Semi-Rigid Braced Excavation in Soft Clay
St. Louis, Missouri
Construction of a 21-foot wide, 28-foot deep braced excavation in Detroit soft clays has been completed. In order to protect an existing 50-year old tunnel adjacent to the excavation, a semi-rigid, tangent wall earth retention system was constructed to minimize the soil movements. The tangent wall was formed by 118 drilled piers with 42-inch in diameter and 41-foot long. The maximum soil lateral and vertical movements adjacent to the excavation were controlled below a magnitude of 2.0 inches, while bottom of the excavation experienced about 3 inches of heave. This paper presents the design considerations and construction performance of the retention system based on geotechnical instrumentation data. Prediction of maximum soil lateral movement based on a finite element analysis and a semi-empirical method conformed well with field measurements. Experience learned from the design and construction will be valuable for future construction of braced excavation systems in similar soil conditions.