Here is a news release about use of cellular concrete in bridge construction. The arches are precast standard density concrete, with an overfill (presumably up to the deck) of cellular concrete. Read the whole story by following the link.    

Cellular concrete in bridge construction

Here are some secrets of contented living that most dogs follow.

• Never pass up the chance to go for a ride.


• Allow the experience of fresh air and the wind in your face to be pure ecstasy.


• Always greet loved ones with enthusiasm, even if they have only been gone five minutes.


• When it's in your best interest, practice obedience.


• Carve out your niche and let others know when they've invaded your territory.


• Take frequent naps and take time to stretch before rising.


• Run, romp and play daily.


• Eat with gusto and enthusiasm!


• Be loyal, no matter what.


• Never pretend to be something you're not.


• If what you want lies buried, dig until you find it.


• When someone is having a bad day, be silent, sit close by and nuzzle them gently now and then.


• Thrive on attention and let people touch you.


• Avoid biting when a simple growl will send the message.


• On hot days, drink lots of water and sleep under a shady tree.


• When you're happy, dance around and wag your entire body.


• No matter how often you're scolded, don't buy into the guilt thing and pout...run right back and make friends.


• Delight in the simple joy of a long rambling walk.

This week was another demo week for the CreteFoamer

Here's a photo of the driveway pour which was completed on Wednesday June 9. It was our intent to do a cellular concrete sub-base under the whole driveway, but city regulators would not permit that. They required the standard compacted fill under all the driveway that was on the right-of-way. On the rest, we used a 3" cellular sub-base (25 pcf) and a reduced density top cap (115 pcf - 5.5 inches thick)

Compaction of the cellular sub-base was not required! There was a materials cost savings, while still getting 3500 psi strength. The "garage end" load had about 7% air because we forgot to tell our producer "no air entrainment" when we ordered, so our density was lower than we intended. If we had chosen to check mix density before adding foam, we would have caught the error. As you can see in the photo, we used wire mesh for the whole driveway. City regulations required that the ROW portion was an Iowa DOT spec mix with no foam added and 800 lbs/Portland per yard. Normal 28 day strength for that mix is about 6500 psi. We used the same mix for the "garage end" load, but added the foam. We will finish the control joints and get a final inspection when it quits raining in "our neck of the woods" as many TV weather personalities, including Al Roker, seem fond of saying.

Here is a link to a 1999 article found on IrishConcrete.ie about Cellular Concrete for Road Construction.

IrishConcrete

I was just alerted to this video by Google Alerts. There are two quick images of buildings in Haiti which were not destroyed by the earthquake.

We are in current discussions with two groups who are rebuilding Haiti.

Facebook video --CLICK HERE - Cellular Concrete in Haiti

Some of our staff members at Richway have been working on the new 4,000 sq ft R&D facility, which will be located on the south end of our polymers building. As Richway has grown into the current 55,000 sq ft factory, so has the need for a larger R&D facility. Here is a picture of the old R&D, along with two current photos of the progress on the new R&D.

Here is a short story about hillside soil stabilization using cellular concrete (aka foamed concrete).

Click on This: Soil "Stabilisation" in Poland


Note: 900 kg/m3 = about 56 pcf (divide kg/m3 by 16 to get approximate density in lbs/cubic foot)

Here is a story about void filling with cellular concrete.

Click here: Void Filling

The lead line notes that "Since foam concrete was first developed in America in 1923 ... ". Most of the time credit is given as first developed in Sweden in the early 1920's. This is the first time I have seen America credited as the "birthplace."

Tony and Bryce are testing the 7-day breaks on some 3/1 Portland-sand cellular mixes we did on our Demo Day last week. More photos will follow of the Demo Day and results of our 7-day break tests.

CreteFoam CMX complies with all ASTM C869 Specifications

A good foaming agent is important in producing cellular concrete. Bubble size, strength, and life are all critical elements. Our new foam, CreteFoam CMX, has just been tested to compliance with ASTM C869 standard specification. CMX development began in May 2009. During field testing, one user noted the "really fine tight bubbles" and found it to much more stable than the foam he had been using. The compliance testing was done by an independent laboratory which is ASTM recognized.

CMX has two polymers for superior performance. The flash point is in excess of 201F, which is important because flash points below 200F require shipping and handling restrictions. Dilution rate is from 1.5 to 4 ounces per gallon. In our 35 years of formulation of foaming agents which are used throughout the world, we have repeatedly "learned" that there is no single universal rate for dilution of any foaming agent. Water hardness, temperature, and other "water quality" factors determine the amount of concentrate required per gallon of water to make a "good" foam.

If you are involved in cellular concrete and would like a free sample of CreteFoam CMX, call Richway at 800-553-2404 (or 319-987-2976) and ask for Tony, Marty, or Rich.

The first demo day of the summer is coming ---Friday April 23, 2010

Join us at 10:00 at the Richway factory at the northwest edge of Janesville, Iowa.  (504 North Maple Street)

We will be doing a demonstration of slab jacking with cellular concrete. (Look down 2 posts to see the "results" of a test we did last week)

We will also be doing some cellular backfill and "showing off" a sidewalk poured in the summer of '08 using a lightweight cellular sub-base.  This sidewalk has not cracked, even though it has had a tandem axle steel scrap truck drive over it many times.

We will be discussing how cellular concrete backfill can provide improved quality and save money by the eliminating the labor cost and time for compaction.

See the beginning of instrumentation for our thermal insulation study.  This will be a 12 month outdoor --- in the ground--- study.  As planned, there will be 20 thermocouples used for monitoring temperatures. 

Depending on time available and the interests of our visitors, we may be doing some lab mixes of magnesium oxide (MgO)  based cements.  These are rapid setting and have high strength.  On the downside, they have potential for dissolving in water over time, so MgO cement based concrete is not recommended for exterior structural applications.

Famous Dave's Bar-B-Que sandwiches at noon and CreteFoamer tee-shirts.

See our new 4000 square foot R&D area and tours of the factory if you want. Finally, we will answer any questions you may have. 

Cellular Concrete Myths

I found this on a website this morning. I consider it to be another myth about cellular concrete.

"Strength and Reliability
Cellular concrete is an almost ageless and everlasting material and is not subject to the impact of time. It does not decompose and is as strong and durable as rock."

This statement was on the website of a producer of cellular concrete equipment in a country other than the USA. In lower densities or with some mix designs, it may decompose and is hardly as "strong and durable as rock." Cellular concrete has a definite role in construction of infrastructure and in building construction, but it is important to recognize where NOT to use cellular concrete.

The same website went on to state:

"Trials undertaken have shown that the closed cell air bubble structure produced by the foaming agent creates cellular concrete with a very low water absorption rate."

"The higher the air content the higher the water absorption figure with a fully submerged sample of mid density (770 kg/m3) foamed concrete absorbing just 13% of water by weight over a 10 day period. A dense heavy weight concrete block submerged for the same period of time absorbed over 50% of water by weight." [770 kg/m3 = 48 lbs/cubic foot)

This flies in the face of our testing at Richway. Cellular concrete, when submerged, absorbs water --- period. You still have the cement and the capillaries to carry the water to the tiny tanks (bubbles created by the foam) for storage. It is a popular myth that cellular concrete does not absorb water and this myth keeps being repeated.

In March 2009, two of us from Richway were doing a presentation about cellular concrete for the Wisconsin chapter of ACI. The question about water absorption was asked and we stated that it did/does absorb water. Our statement was confirmed immediately by Prof. Konstantin Sobolev, the (then) newly elected Chairman of the ACI 523 (Cellular Concrete) committee. (He is a materials professor at the University of Wisconsin - Milwaukee and was attending the meeting.) He gave a short explanation of the mechanism of water absorption for cellular concrete.

This is Ryan and Marty after a blowout of high pressure cellular concrete from a slab jacking experiement here at Richway.

Here is an interesting paper listing some uses of cellular concrete.

Click Here

   

On their website they say 




"Cematrix is a manufacturer and supplier of technologically advanced cellular concrete products with applications in a variety of markets, including oil and gas construction and infrastructure construction. It is headquartered in Calgary, Alberta."

Thanks for visiting us at World of Concrete 2010.

The show size and attendance was down, but our visitor count was up! While visiting with all of you, we learned a lot and heard some really interesting ideas for the use of cellular concrete. We'll be sharing some of those with you in the coming weeks. Every time we exhibit we learn a lot and hope that you learn from visiting us.

If you have questions or want to talk about cellular concrete, call us at 800-553-2404 or 319-987-2976.

You may also contact us online here.

Flowable fill, as it is often called, more formally known as Controlled Low Strength Material (CLSM), has an important place in infrastructure construction. It typically has a small percentage of cement (which may include fly ash), aggregate (usually fine), sometimes local soil, and lots of water.  The water provides the flowability, but must be drained away at the deposit site, which can be a problem.  Foam can be used in place of water to provide flowability and does not have to be dealt with at the deposit site.  Furthermore, use of foam can create a lower density fill which put less load on the substrate below the fill. You may have to slightly increase the cement percentage to get required strengths, or just allow the foam to collapse at the deposit site and then be sure you have completely filled the deposit site. This will result in a "full density" fill.  If you choose the latter approach, you need to use a "flash foam," which is different from our standard CreteFoam concentrate.  Want to know more?  Call 800-553-2404 and talk to Tony, Marty, or Rich.

Lying within the City of Bath World Heritage site, the picture-postcard village of Combe Down is
home to what is thought to be the world's largest single use of foamed
concrete, with the estimated final volume approaching 600,000 cubic meters
and due for completion by December 2009.  {785,000 cubic yards]

Click on this link to learn more about this multi-year project in southwest England.

CLICK HERE



The concern is that the supports which were left during mining of the limestone were too small and too far apart to safely support the ceiling of the mine.

Last Friday, October 16, these two skidmount Cretefoamers were "posed" and photographed before crating for shipment. The one on the left is a CFVT-8C-SM and the one on the right is a CFVT-20C-SM. Skidmount units include water tanks and gas engine powered air compressors (diesel available) to make a complete stand-alone package, ready to go to work. The "8C" has a foam output rate of 8 CFM and has a 100 gallon water tank. The "20C" has a foam output rate of 20 CFM, with a 300 gallon tank. Both can run continuously -- there is no pre-mixing and no guessing required. Rugged, reliable, and simple are three of the many words which describe Richway CreteFoamers. Unfortunately, these are both powder coated black and thus don't show up very well.