The Good, the Bad, and the ….

For my research project, I am looking into flyash concrete as a suitable replacement for current concrete. Concrete, as I stated in a previous post, is the most widely used material in building construction, and as a result of this, creates huge CO2 emissions into the atmosphere. Flyash concrete is being used widely into days concrete structures. Flyash, when it is used with concrete, is mixed together to reduce the amount of aggregate and portland cement that is needed to be used. The standard mix is usually about 9% flyash with the rest normal cement. This is what is being used in today’s construction for projects, and I am proposing that flyash, in the future, replace concrete 100%. I am currently looking into the research as of if this would be possible, and am finding some great feedback.

35W Bridge Casting

35W Bridge Casting

One thing that I will be using in my research is the 35W bridge in Minneapolis, MN as a precedent. The 35W bridge collapsed on August 1, 2007 and when they rebuilt it, using a mixture of flyash and concrete. Structurally, the flyash doesn’t weaken the concrete, and you are removing CO2 emissions in 2 ways: both as less concrete is used in a heavily harmful production, and the flyash isn’t going to a landfill thus not releasing CO2 into the atmosphere. There is also arsenic, lead, and mercury in flyash, and release of these into the atmosphere is stifled when it is locked into concrete form.

Flyash has many benefits, and downfalls as well, but my research will be in seeing if it is a viable replacement for the future in building construction.

 

minnesotaindependent.com

http://minnesota.publicradio.org/features/2008/09/17_35wbridge/

Advertisements

One comment

  1. wils1489

    I like that fact that you are trying to come up with a suitable replacement for cement but, you are proposing something that is already in the works. “Approximately 60-70% of central Texas ready-mix suppliers offer flyash concrete. Some suppliers provide it automatically,” and that’s how it should be. You’ve already listed the positive things that it would do for the environment but, it has a lot more potential than that. Here is a list that I found online of all its possibilities.

    “Although flyash offers environmental advantages, it also improves the performance and quality of concrete. Flyash affects the plastic properties of concrete by improving workability, reducing water demand, reducing segregation and bleeding, and lowering heat of hydration. Flyash increases strength, reduces permeability, reduces corrosion of reinforcing steel, increases sulphate resistance, and reduces alkali-aggregate reaction. Flyash reaches its maximum strength more slowly than concrete made with only portland cement. The techniques for working with this type of concrete are standard for the industry and will not impact the budget of a job.”

    The devastation caused by the collapse of the old 35W bridge inspired the use of flyash concrete in the new 35W bridge. They needed a way to make the concrete stronger and as above, not only does flyash make it stronger but, it improves the performance and quality of the concrete. The use of flyash concrete is on the rise and it’s only a matter of time before is does replace regular concrete as you are proposing.

    http://flyash.sustainablesources.com/

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: