Recyled content of steel shapes

[StructuralEngGuy]

Hi everyone,

Do any of you have experience with specifying recycled content of steel shapes? With so much emphasis on green buildings and LEED these days, I've been having to specify recycled content percentages in steel shapes in my specifications. Anyone done this before and have a general rule of thumb to follow? Seems to me like it shouldn't really matter as long as the steel still meets the applicable yield and ultimate strength requirements it needs to for ASTM requirements.

 

[kslee1000]

Foreign particles, especially chemically reactive/active.
No specific informations. But from experience of Japanese cars built in before 80s, which seemed to use steel made of cheap, dirty recycled scraps for body. Their engin last for 15 years or more, while needs new body every 4-5 years. Technology may have advanced to take care of this, just watch out.

 

[Ron]

SEG....hitting a hot button here.

As structural engineers, we should not be put in a position to dictate a percentage of recycled material (particularly as a minimum) in anything! We are structural engineers. We know the finished properties of the material we use, but we don't need to tell a steel producer how to do his job. He's responsible for quality control of his products. He has to meet standards such as A36, A570, etc., all of which were developed long before "green" was popular.

If possible, resist it. Specify that preference will be given to producers who subscribe to "green" processes and develop "green" products, but don't get into telling them how much of anything to put in structural steel.

 

[hokie66]

We are getting into this same nonsense in Australia, not only for structural steel, but other components of construction. The architect says he has to include this kind of thing in the specifications because the state government or commonwealth government require it. The insane are ruling the asylum.

 

[H57]

You can resist specifying it, but it is the reality of the design world right now. LEED allows for the contractor to consider that all steel has a 25% recycled rate without documentation. This is because the actual recycled rate of steel is higher than that. In reinforcing I am told that it can be 100%. On the last LEED project I worked on the LEED consultant asked that the steel have recycled contents of 100% for reinforcing bar and 80% for all structural steel shapes. I was the one that put this criteria into the specifications (as I am the one specifying the steel). It has not been built, but there was not a single question about this that was raised during bidding. This tells me that either the suppliers don't have a problem with this or it wasn't looked at during the bid. Considering the depth of the bid and the questions that were raised during the process I tend to think that the suppliers don't have a problem meeting these requirements.

 

[hokie66]

Who polices this sort of thing? Does the "LEED consultant go to the steel mill or to the rolling mill to determine if the requirements are being met? How would he/she know?

 

[JStephen]

I was under the impression that some of the mills not in mining areas work essentially 100% off scrap. In which case, you could just specify which mills the material could come out of.

The whole process seems relatively pointless to me, though. Scrap steel has value, and is largely recycled. If you specify more recycled steel for your project, you're not going to magically generate more scrap into existence. Meaning the same amount of iron ore is going to be mined, only it will be used on someone else's project instead of yours. That's not exactly a big accomplishment.

 

[JStephen]

Oh, and in the process, you're going to use more fuel to haul your "green" steel around the country or the globe.

 

[hokie66]

But JS, the people who come up with these silly schemes don't use logic.

 

[Ron]

H57...my guess is they didn't read the specs.

For rebar, 100% is common, particularly in electric arc furnaces. For rolled shapes, I would be surprised if 80% is achieved routinely, though it could certainly be. Keep in mind, the higher the percentage of scrap, the more difficult the chemical control of the steel will be. That's one reason there are essentially no chemical controls on rebar, yet structural shapes have reasonably tight controls on the chemistry.

For my $0.02, I just think such quotas are wrong and generated by people who have no concept of the process, just a political position. As hokie66 pointed out, logic doesn't enter the process.

 

[csd72]

I am trying to find my notes on this but I believe in the UK that rebar is 100% recycled and regular steel is made up of at least 60% recycled and has been like this for a few years.

In the UK, sustainanability has been on the agenda for quite some time now and is considered an integral part of the design process (along with health and safety considerations). It does make sense to have the engineer involved in these decisions because we do make a difference.

Yes the truth is very complicated and often contradictory but we have to start somewhere. When China and India are developed, we will not have enough resources to maintain the current resource usage rates that the western world has enjoyed so far.

 

[Ron]

csd72...I am certainly an advocate of recycling, and in general, protection of our environment and resources. I am not in favor of this being a political process and having ignorant people making random decisions for the masses without sufficient technical discourse and input.

I grew up in a recycling environment (my father had a recycling business), so I know it reasonably well, have seen first hand the benefit, have participated in the process (knee deep in aluminum cans, running a bailing machine...working a smelter to melt aluminum transmission casings...dismantling electrical transformers to salvage the copper wire and steel plates), and continue to recycle.

As you noted, your country has been recycling and using the materials for years...long before the "green" push. Interestingly, this is one area that the free market was ahead of the politically correct movement and its political expedience.

I fully agree that engineers and scientist need to be involved. Perhaps we could make a difference if heard through the social ignorance and logic void of the current trend.

Diatribe over....

 

[bridgebuster]

I don't see how the recycled content can be done unless you make arrangements with a specific mill.

Contact AISI - American Steel and Iron Institute

http://www.steel.org

As I recall they and AISC advertise that most of the steel produced in the US is better than 90% recycled material.

 

[csd72]

Ron,

What you describe is exactly what occured. The IStructE got involved in the process and has been integral in providing guidance.

If only ASCE could do the same.

 

[H57]

The point of recycled content in LEED isn't specific to steel. You get a point (or more than one) depending on the percent of all materials used on a project that are made with recycled materials. It then becomes about identifying products that recycled material can be used.

To say that it won't do anything for the environment to require recycled steel may be true (as it won't directly increase the amount of recycled steel), but to say that using recycled products in general does nothing for the environment would be foolish.

In regards to who is verifying the recycled content, that comes down to the contractor. For all materials used in a project LEED requires that the percent recycled content be calculated by cost. If material cost is not known a standard 55/45 labor/material split is acceptable. Without documentation of recycled content you get no credit. Steel is the one exception as they allow you to consider 25% recycled content w/o documentation. Some suppliers provide documentation while others will not.

With this credit it seems to be left to the contractor to a large degree. The specs provide ways to get recycled content along with what the overall goal is. The contractor needs to tabulate and organize to see if he will meet the goals or not. If needed products need to be substituted to meet the overall project goal.

 

[hokie66]

H57,

None of us are talking down the importance of recycling. We just can't understand how all this paperwork (remember the forests) helps in controlling what really are market forces. The recycling industry is well developed and competitive. More bureaucracy doesn't help.

 

[kslee1000]

Metals and papers are easily recycled. How about plastics?
Maybe considering recycled plastic money, coins..a way to go - 100% recycled.

 

[csd72]

The following quote is from the IISI
"The recycled metals market is already mature and a recycled content approach may create market distortions and environmental inefficiencies. If a designer specifies high recycled content in a well meaning effort to reduce environmental impact, it may stimulate the market away from products where recycling is most economical. For metals, where there is a limited supply of recyced feedstock, market stimulation is ineffective and may result in inefficient processing and unecessary transportation'

 

[StructuralEngGuy]

Thanks all for the input. I think it would be worthwhile to contact the steel fabricators/mills near the project site and see what they're take is on the topic. I'm sure they've been asked the question plenty of times by now.

 

[JLNJ]

Some of those LEED bars are set so low that the "points" are almost automatic. I think the recycled steel content is one of them.