Facilitating interaction between engineers and contractors

Editor’s Note: Bob Koerner wrote about the Geosynthetics Institute‘s second Inspector Certification Program in the August/September 2011 issue of Geosynthetics and he responds to this query.

Question

From: Chet Soydemir
To: Ron W. Bygness
Subject: GSI News

Dear Editor of Geosynthetics:

I read with great interest the “GSI News” section prepared by Dr. Robert Koerner in the August/September 2011 issue of Geosynthetics (“GSI’s second Inspector Certification Program.”)

It is indeed illuminating that 64% of the “failure mechanisms” observed in the failed MSE walls, berms, and slopes is “water related” (i.e., “internal” and “external” water), which comprises nearly two-thirds of all “failures.” In other words, if I may suggest “failure” is associated with “inadequate drainage.” I first learned this phenomenon from Prof. Arthur Casagrande in 1958.

If I may also suggest that most often the design of MSE walls, berms, and slopes is performed by the contractor’s technical staff who assumes drained conditions in the design to stay competitive. I strongly believe that drainage is more so a design issue than a construction issue, and it should be implemented by the project’s geotechnical engineer.

Thus, I think that even though the planned “second GSI Inspector Certification Program” is sound and useful, the more critical issue is to facilitate the interaction between the geotechnical engineer and the contractor in every (small or big) MSE project in dealing with the drainage elements.

Chet Soydemir, Ph.D., P.E.
Senior Geotechnical Consultant, Environmental Compliance Services Inc.,Woburn, Mass.

GSI responds

Dr. Soydemir has written a wonderful letter that fits perfectly into our perspective of the issue.

We only wish that GSI could facilitate (make that “force”) the interaction between the geotechnical design engineer and the owner/contractor/project manager. [Unfortunately], that is beyond our means and capabilities.

What we can do (albeit, somewhat less directly) is to have qualified field inspectors who can:

1. transmit design oversights to the geotechnical design engineer and
2. to report contractors’ inadequate performances to the owner/contractor/project manager.

Our hope at this point, since the program is just beginning, is to have stakeholders in the technology recommend and implement the use of these certified field inspectors of MSE walls, berms, and slopes. We encourage the readers of Geosynthetics magazine to do so and to distribute the information to others as well.

Bob and George Koerner
Geosynthetic Institute

Join the discussion

To post your thoughts on these comments, fill out the comment form on the bottom of the article “GSI’s second Inspector Certification Program,” or send your comments to editor Ron Bygness at rwbygness@ifai.com.

Comments and letters can contain opinions of individuals who are writing and do not necessarily reflect the views of Geosynthetics magazine or the Industrial Fabrics Association International.