Session 01: Case Histories of Unexpected Behavior and Failure of Shallow, Deep and Other Foundations
Location
Arlington, Virginia
Date
13 Aug 2008, 5:15pm - 6:45pm
Abstract
Settlement during hydro-testing of two 30-m diameter oil tanks was generated mostly by a layer of highly plastic clay at about 10 m depth. Based on about 5 months of readings on one of the tanks, the total predicted settlement at the tank perimeter was about 300 mm (with little differential movement) and at the center was closer to 550 mm. The settlement of a 7-m diameter water tank located close to the oil tanks followed quite a different pattern during hydro-testing. Within about 6 days, the tank had settled about 130 mm on one side, but only about 20 mm on the other. The water tank was only about half the height of the oil tank, and the diameter was less than one quarter, resulting in loading at the depth of the plastic clay layer of less than 15% of that of the oil tank. Yet, settlement rates were much faster than those of the oil tank, and differential settlement was not anticipated based on the depth of the clay layer. This paper describes the settlement measurements and computations made for the oil tanks and describes the efforts made to determine the reasons for the unanticipated settlement of the water tank and the actions taken to remedy the situation.
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
Far, Ashraf El and Davie, John, "Tank Settlement Due to Highly Plastic Clays" (2008). International Conference on Case Histories in Geotechnical Engineering. 32.
https://scholarsmine.mst.edu/icchge/6icchge/session_01/32
Tank Settlement Due to Highly Plastic Clays
Arlington, Virginia
Settlement during hydro-testing of two 30-m diameter oil tanks was generated mostly by a layer of highly plastic clay at about 10 m depth. Based on about 5 months of readings on one of the tanks, the total predicted settlement at the tank perimeter was about 300 mm (with little differential movement) and at the center was closer to 550 mm. The settlement of a 7-m diameter water tank located close to the oil tanks followed quite a different pattern during hydro-testing. Within about 6 days, the tank had settled about 130 mm on one side, but only about 20 mm on the other. The water tank was only about half the height of the oil tank, and the diameter was less than one quarter, resulting in loading at the depth of the plastic clay layer of less than 15% of that of the oil tank. Yet, settlement rates were much faster than those of the oil tank, and differential settlement was not anticipated based on the depth of the clay layer. This paper describes the settlement measurements and computations made for the oil tanks and describes the efforts made to determine the reasons for the unanticipated settlement of the water tank and the actions taken to remedy the situation.
