Location

New York, New York

Session Start Date

4-13-2004

Session End Date

4-17-2004

Keywords and Phrases

Slope movement, Slope stability, Site instability, Shale

Abstract

A study conducted for St. Louis County of Missouri, United States of America classified several areas of the county as unstable for any type of construction because of the presence of high plastic shaley clay or clayey shale on sloping bedrock. These areas are considered to have a potential for site instability to occur due to any change in natural conditions that may increase the moisture content of the high plastic shaley clay or clayey shale. A two-story parking garage, founded on shallow foundations, constructed in one of the potentially unstable zones, showed some movement after several years of its construction. After movements in the structure were observed, further review of the subsurface conditions revealed that as a result of construction at the site, the clayey shale layer became exposed, thus, creating easy access for water to enter this layer. Infiltration of water caused softening of the clayey shale layer, which in turn caused movements in the structures constructed on the site. This paper presents the detailed information about the subsurface conditions and type of structures constructed on the site.

Department(s)

Civil, Architectural and Environmental Engineering

Appears In

International Conference on Case Histories in Geotechnical Engineering

Meeting Name

Fifth Conference

Publisher

University of Missouri--Rolla

Publication Date

4-13-2004

Document Version

Final Version

Rights

© 2004 University of Missouri--Rolla, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

Share

 
COinS
 
Apr 13th, 12:00 AM Apr 17th, 12:00 AM

A Case History of Site Instability Due to the Presence of a Shale Layer Above Sloping Bedrock

New York, New York

A study conducted for St. Louis County of Missouri, United States of America classified several areas of the county as unstable for any type of construction because of the presence of high plastic shaley clay or clayey shale on sloping bedrock. These areas are considered to have a potential for site instability to occur due to any change in natural conditions that may increase the moisture content of the high plastic shaley clay or clayey shale. A two-story parking garage, founded on shallow foundations, constructed in one of the potentially unstable zones, showed some movement after several years of its construction. After movements in the structure were observed, further review of the subsurface conditions revealed that as a result of construction at the site, the clayey shale layer became exposed, thus, creating easy access for water to enter this layer. Infiltration of water caused softening of the clayey shale layer, which in turn caused movements in the structures constructed on the site. This paper presents the detailed information about the subsurface conditions and type of structures constructed on the site.