The photo of this failed SPL wall is pretty remarkable. It was discussed in a thread I came accross on EngTips.com. The originator of the thread (kleo) says he was involved from the contractor side on this project in a mountainous rainforest region near Cuba. He also says the wall was designed by “FHWA”, don’t know if that means US FHWA or what. But if so, I have no idea where this project would be located. The wall was designed for a 15-ft high cantilever with around 20-ft embedded with the last 7-ft being into bedrock. Check out the thread to kick in your hypothesis for kleo.
The FHWA has released for download a comprehensive update to the 1999 O’Neil and Reese manual “Drilled Shafts: Construction Procedures and Design Methods”, lovingly referred to in the industry as the “Brown Book” or the “Drilled Shaft Bible”. This 2010 manual from the National Highway Institute (NHI) of the FHWA is entitled “Drilled Shafts: Construction Procedures Procedures and LRFD Design Methods” and was authored by Dan A. Brown, Ph.D, P.E. of Dan Brown and Associates, John P. Turner, Ph.D, P.E. of the University of Wyoming, and Raymond J. Castelli, P.E. From an FHWA Memo on the manual:
Distributed with this memorandum is the publication entitled "Drilled Shafts: Construction Procedures and LRFD Design Methods" (FHWA-NHI-10-016). This manual is the reference text used for the National Highway Institute (NHI) course numbered 132014 on Drilled Shafts. The publication will become the tenth in the series of geotechnical engineering guidelines called "Geotechnical Engineering Circulars." Geotechnical Engineering Circular (GEC) No. 10 is prepared as a significant revision and update to "Drilled Shafts: Construction Procedures and Design Methods" (FHWA IF-99-025), and reflects the standard of practice for the design, construction and inspection of these features. The guidance is developed following Load and Resistance Factor Design (LRFD) procedures and will enable engineers to identify and evaluate technical feasibility and potential applications. The text is developed with a sufficiently broad scope to be of value to a wide range of transportation specialists responsible for assisting with selection, design, development of materials specifications, construction monitoring, and contracting methods for Drilled Shafts.
Click through for the download link and some preliminary comments on what has been updated in this significant new publication in the drilled shaft construction industry as well as the geotechnical engineering profession.
[Disclosure] NCS Consultants is the employer (day job) of Randy Post, the owner of this site. [/Disclosure]
Geotechnical engineers who encounter MSE retaining walls or Mechanically Stabilzed Earth Walls are undoubtedly familiar with the FHWA NHI manual on “Mechanically Stabilized Earth Walls and Reinforced Soil Slopes”. This manual, along with the NCMA manual that is used for non-transportation projects, is virtually the bible for MSE wall design. In late summer/early fall of 2009, a revised version of this manual will hit the streets. Read on for more details.