Location
Arlington, Virginia
Date
15 Aug 2008, 11:00am - 12:30pm
Abstract
Vertical containment walls have been used as barriers to cut off hazardous fluid and chemical flow in the ground at contaminated sites. An application of this technique in South Carolina is to construct a 1.6-mile long containment wall along a dike using cement-bentonite slurry, which features low permeability and high compressive strength. However, concerns about the stability of the cement-bentonite slurry trench have been raised because an existing soil-bentonite wall will be in very close proximity to the alignment of the cement-bentonite slurry trench; and the shear strength of the existing soil bentonite backfill is considered to be low. Excessive overbreak of the new trench sidewalls is anticipated during construction. Utilizing the data obtained from the geotechnical borings drilled on the dike and CPT results, a parametric study was carried out in order to establish the minimum distance between the cement-bentonite slurry trench and the existing soil-bentonite backfill. Different cases were analyzed according to the strength parameters of the soil-bentonite backfill and the water level of the pond. In this paper the authors present the method and results of the stability analyses of the cement-bentonite slurry trench against wall collapsing. The calculated factor of safety with varying soil-bentonite backfill friction angles is plotted as function of the distance to the proposed trench. The results are discussed and recommendations are given to minimize the probability of trench overbreak. As a means to monitor the stability of the dike, inclinometers were installed prior to trench excavation. With the new trench being advanced, the measurements from the inclinometers show the movement of the dike due to trenching. These data are also discussed in the paper.
Department(s)
Civil, Architectural and Environmental Engineering
Meeting Name
6th Conference of the International Conference on Case Histories in Geotechnical Engineering
Publisher
Missouri University of Science and Technology
Document Version
Final Version
Rights
© 2008 Missouri University of Science and Technology, 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
Wang, Xiaohai; Bernardeau, François G.; and Younan, Jean-Claude, "Slurry Trench Stability Analysis – Constructing Cement-Bentonite Slurry Trench Adjacent to Existing Soil-Bentonite Backfill" (2008). International Conference on Case Histories in Geotechnical Engineering. 24.
https://scholarsmine.mst.edu/icchge/6icchge/session05/24
Slurry Trench Stability Analysis – Constructing Cement-Bentonite Slurry Trench Adjacent to Existing Soil-Bentonite Backfill
Arlington, Virginia
Vertical containment walls have been used as barriers to cut off hazardous fluid and chemical flow in the ground at contaminated sites. An application of this technique in South Carolina is to construct a 1.6-mile long containment wall along a dike using cement-bentonite slurry, which features low permeability and high compressive strength. However, concerns about the stability of the cement-bentonite slurry trench have been raised because an existing soil-bentonite wall will be in very close proximity to the alignment of the cement-bentonite slurry trench; and the shear strength of the existing soil bentonite backfill is considered to be low. Excessive overbreak of the new trench sidewalls is anticipated during construction. Utilizing the data obtained from the geotechnical borings drilled on the dike and CPT results, a parametric study was carried out in order to establish the minimum distance between the cement-bentonite slurry trench and the existing soil-bentonite backfill. Different cases were analyzed according to the strength parameters of the soil-bentonite backfill and the water level of the pond. In this paper the authors present the method and results of the stability analyses of the cement-bentonite slurry trench against wall collapsing. The calculated factor of safety with varying soil-bentonite backfill friction angles is plotted as function of the distance to the proposed trench. The results are discussed and recommendations are given to minimize the probability of trench overbreak. As a means to monitor the stability of the dike, inclinometers were installed prior to trench excavation. With the new trench being advanced, the measurements from the inclinometers show the movement of the dike due to trenching. These data are also discussed in the paper.
