The Deep Foundations Institute’s Tieback and Soil Nailing Committee recently concluded that a shortage of current and complete soil nail wall performance data exists to guide engineers, specialty geotechnical contractors, and owners. Furthermore, it was recognized that the state-of-practice in analysis and design is based on domestic and foreign case studies that are more than 10 years old, dating back perhaps to the French CLOUTERRE project originally translated into English in 1991. As a result, the committee is undertaking a new, national effort to collect, categorize, and begin analysis of soil nail wall performance data.
Data types sought are typical project, geotechnical, and wall geometry information; design and analysis methods and software; construction and monitoring duration; settlement and lateral deformation data; and nail strain gauge data. The committee wants to review all documented case histories of soil nail walls that performed well or poorly, both for temporary and permanent applications. The primary goal of this collection and analysis process is to confirm or adjust the soil nail wall movement envelopes stated in the current literature and to compare measured soil nail loads and stresses to those predicted by the available methods of analysis. Future teaming with academia will be sought by the committee to facilitate a complete review, extract and analyze the desired performance data, and possibly synthesize updated prediction methodologies.
To help in this effort, click here to complete a form for each pertinent project and return it to the committee for initial review and classification by Sept. 30, 2008.