I have the privilege of serving as an adjunct professor at the University of Arkansas with the assignment of teaching construction management to our senior civil engineering students. After reading [Bernie Siben's] recent article in CE News ("So you want to be a project manager?" September 2011, page 35) I wanted to congratulate [him] on the clarity of the expression of [his] thoughts on the skills required of a construction manager. Being an effective manager requires many more skills than the technical expertise of a design engineer and these are the qualities that we attempt to convey to the students. [Siben] expressed this very well in this article and I hope that I have your permission to share [his] wisdom and ideas with my class. Certainly it is one thing to be a capable engineer and another to be a successful manager.
Thank you! The article by [Bernie Siben] was simply the best article I have ever seen about down and dirty project management (PM) and project managers. I have been a certified project management professional (PMP) for many years and have been teaching PMP training to some friends/co-workers in the government. I immediately sent them all the URL and told them if this is not what they think PM is about, they should consider another life's work. Great job!
Franklin Smith, PMP
Opportunity Calls, LLC
Thanks for the article on leadership in the September issue of CE News ("The —L' word," page 6). [Mark Zweig] nailed it.
Carl F. Bonner, P.E.
Making retaining walls succeed
The author of "When retaining walls fail" (CE News, June 2011, page 34) says, "[Mechanically stabilized earth (MSE)] walls fail at an alarmingly high rate – about 1 in every 1,000," but his examples are all dry-cast modular block walls with geosynthetic soil reinforcements. MSE walls with steel soil reinforcements and precast concrete panels have a significantly lower failure rate – about 1 in 5,000 – after tens of thousands of critical structures and a 40-plus-year history.
The key reasons for this performance difference are:
- Most steel-reinforced MSE walls support highway loading and conform to AASHTO specifications, which control foundation preparation, drainage systems, backfill quality, compaction, and construction inspection.
- AASHTO-specified MSE backfill is free draining, avoiding the water buildup often identified as the cause of blown out blocks and failed geosynthetic-reinforced walls.
- Steel-reinforced walls are supplied through a single source of responsibility – a single supplier designs and manufactures its own quality-controlled wall components and advises the owner and contractor regarding installation.
Many of these MSE suppliers belong to the Association for Metallically Stabilized Earth (AMSE), which promotes single-source-of-responsibility for MSE wall design and supply and advocates for specifications which ensure added value, performance, reliability, and long-term safety. We believe our members' efforts, and their single-source-of-responsibility approach, make the difference between 1 in 5,000 and 1 in 1,000. This is something all owners and contractors can benefit from.
Robert A. Gladstone, P.E.
Association for Metallically Stabilized Earth
In your CE News article, "Transportation Projects Roadmap" (September 2011, page 18), you provided a table listing major transportation projects. One listed was the I-269 Loop; however, you did not have a project website. Although they are not doing the design work for the interstate, the consulting firm of McBride Dale Clarion has been contracted to study the above-referenced corridor as well as help "steer" associated development so as to have it align best with local needs and goals. They are early in the process, and the study area is only that part of the I-269 loop that falls within DeSoto County, Miss. On the Tennessee side of the I-269 Loop there is some discussion about preparing a similar study, but no RFP has been issued to date. The website for the DeSoto I-269 study is www.desotodiscovery.com I've also attached a map of the loop to show how it actually traverses two states and four counties. Hope it helps with your research, and we appreciate any good press we get for this project, the Southern Gateway Project (bridge over Mississippi River), and the MRIMF (Memphis Regional Intermodal Facility, which is part of Norfolk Southern's Crescent Corridor).
Dan Frazier, AICP