Domestic or Foreign Steel Reinforceme...

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Author Message Jerome J. Lazar, RA, CCS, CSI, SCIP Senior Member Username: lazarcitec Post Number: 914 Registered: 05-2003 Posted on Thursday, October 25, 2012 - 09:28 pm:    One of our clients wants us to open up the Concrete spec by allowing for Foreign Steel, this is a privately funded project - is this wise? advantages and disadvantages? Mark Gilligan SE, Senior Member Username: mark_gilligan Post Number: 513 Registered: 10-2007 Posted on Thursday, October 25, 2012 - 09:46 pm:    Technically there should be no problem. The only concern is that the quality control from the foreign suppliers may not be good enough. It is not clear that there is any basis for this concern. If somebody wants to have an extra level of comfort work with the structural engineer to specify some physical tests of the reinforcing steel supplied. Robin E. Snyder Senior Member Username: robin Post Number: 434 Registered: 08-2004 Posted on Thursday, October 25, 2012 - 10:35 pm:    Foreign from where? Europe - probably ok. China - be cautious scott piper (Unregistered Guest) Unregistered guest Posted on Friday, October 26, 2012 - 09:08 am:    it may depend on what the structure is. If the R-bar is basically temperature reinforcement in foundation walls it would be less of a worry. If it is structural reinforcement in a suspended structural concrete slab it would be another story. Mark Gilligan SE, Senior Member Username: mark_gilligan Post Number: 514 Registered: 10-2007 Posted on Friday, October 26, 2012 - 02:39 pm:    Suggest we deal with facts and not emotions. The reality is, and I speak from the perspective of California experience, there have not been problems with substandard reinforcing steel. In the case of California public schools where there is no requirement for US sourcing reinforcing, the reinforcing is regularly subjected to physical tests. The report from testing labs is that these tests never fail. Thus the objective data suggests either that there is no foreign steel in the market or there is no reason to be concerned about foreign steel. Normal practice is for the specifications to require submission of mill certifications for rebar. The mill cert provides information on chemical properties as well as results of physical tests. As I stated above if one still has concerns it would be appropriate to specify physical tests of the steel being used on the project for all sources of reingorcing steel. This should identify any substandard material. I do not believe that there is a rational reason to impose additional constraints related to the source of the reinforcing steel. Ultimately I suggest that the structural engineer should take the lead in specifying requirements related to the quality of reinforcing steel. Robin E. Snyder Senior Member Username: robin Post Number: 435 Registered: 08-2004 Posted on Friday, October 26, 2012 - 02:45 pm:    @Mark: Who is dealing with emotions? Mill certificates can be faked. J. Peter Jordan Senior Member Username: jpjordan Post Number: 511 Registered: 05-2004 Posted on Friday, October 26, 2012 - 03:49 pm:    It is my understanding that steel reinforcing is one of the items that is readily available from "minimills" located around the country. These facilities produce steel with high-recycle content and qualify for regional materials under LEED. That being said, if you are concerned about the quality, insert a testing requirement for 3rd-party testing from steel delivered to jobsite; say, 3 random samples for every ton (or half ton) of rebar delivered to the jobsite. This should be able to be done relatively quickly and should confirm that the steel meets the specification. Mark Gilligan SE, Senior Member Username: mark_gilligan Post Number: 515 Registered: 10-2007 Posted on Saturday, October 27, 2012 - 01:31 pm:    There are real concerns about the quality of construction but in my experience the problems are usually the result of short cuts and bad practices as opposed to deliberate fraud. There is extensive literature that tells us that an individual’s perception of risk is typically driven by emotions as opposed to the facts. We often worry about risks that are trivial while being oblivious to other more serious risks. Construction quality assurance is something that we do because the building code requires it but designers and owners typically do a poor job of monitoring quality assurance activities. It is easy to focus on “foreign” sources of problems while ignoring domestic sources. The focus on foreign sources is often the result of xenophobia as opposed to facts. Many of the common problems are the result of domestic sources yet we tend to pay them less attention. In the case of reinforcing steel while I believe the problem is minimal the concern can be addressed by physical tests by a testing lab retained by the owner. Do the tests and move on unless you are concerned that the testing lab will fake the results. There is no end to the nature of concerns that can be imagined. Recently I have been looking at specification requirements that place additional limits on the chemical composition of fly ash. Typically the engineers and architects have no idea why the requirement was added but they defend keeping them in the specification because they are in the master specifications of reputable firms. When we look at all of the concrete in place that does not have these additional limits we do not see problems that result from the failure to specify these limits. Still it is very difficult to extract these additional limits on fly ash from specifications.