Beyond Elevated Metal Deck Construction - Navy Uses Lightweight Concrete for Double Deck Floating Pier

Published by Clint Chapman on June 25, 2008 in Structural Lightweight Concrete. 0 Comments

We are all aware of the many benefits expanded shale & clay lightweight aggregate concrete offers when utilized in elevated metal deck construction, but have you considered other, not so typical, applications where structural lightweight concrete can aid in solving design problems?

True, lightweight concrete will reduce inertial forces in seismic design situations, can allow for the elimination of spray-on fire proofing underneath metal decks, can reduce the amount of steel throughout the structure, can significantly reduce the cost of your foundation, and the list goes on when considering elevated metal deck construction. The everyday use of structural lightweight concrete in pre-cast operations as a means of reducing transportation requirements continues to be more influential in today’s escalating fuel cost environment. The utilization of lightweight aggregate concrete in various applications beyond pre-cast can enhance your bottom line through the efficient use of your already stretched fuel budget. However, the list of applications where structural lightweight aggregate concrete can aid in solving design problems stretches far beyond these everyday applications.

Consider the recently constructed “test section” of the Modular Hybrid Pier cast in Tacoma, WA for the US Navy. This double-deck floating pier utilizes high performance lightweight concrete, and according to the July-August 2005 issue of the PCI Journal, is expected to deliver a 100 year service life while reducing traditional repair costs by as much as 80%. I invite you to take a closer look at this innovative use of lightweight concrete through this PCI Journal article.

Tacoma Dry Dock Flood
Flooding of the dry dock in Tacoma, WA in preparation for floating the test section of the Modular Hybrid Pier.

Modular Hybrid Pier
One of the Modular Hybrid Pier test sections as it is floated into the Port of Tacoma.

I would love to hear some stories about those projects you have been involved with where structural lightweight concrete has solved some “atypical” design problems.

Clint Chapman
Sales Representative

Clint Chapman is a sales representative for TXI Expanded Shale & Clay. He has assisted on the design of various structural lightweight concrete applications for the past eight years.

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Lightweight Concrete Masonry: An Emerging New Approach to Sustainability

Published by Stephen Stange on May 21, 2008 in Masonry. 0 Comments

“Sustainable development-a philosophy that focuses on meeting our construction needs today without depleting future resources.” - Portland Cement Association, Concrete Thinker.

In construction, the “green” building movement and “sustainability” are now familiar topics and hotly discussed. Contributing to this discussion is concrete masonry - a structural concrete wall system. In this discussion, I won’t attempt to address all of the environmental benefits attained during construction as well as for the life of the building. After analysis, however, concrete masonry systems are very often the solution to the quest for green construction.

Why is concrete masonry? The main reasons involve minimal maintenance, long life and resistance to damage from moisture, weathering, and vandalism, resistance to earthquake, wind, and fire, economical installation, sound attenuation, and last, but not least, energy savings due primarily to thermal mass effects.

In addition, structural-grade lightweight concrete masonry units, using lightweight aggregates, are up to 25% lighter than traditional masonry units. Lightweight CMU can speed installation by substantially increasing the number of units per hour that a mason can lay.1, 2, 3

Promoters of wall systems today offer plenty of information as to why their systems are sustainable or green. Please feel free to comment as to how the concrete masonry wall system can facilitate the development of LEED points for your project. But just for thought, consider the interesting and concise definition of sustainability offered at the beginning of this article.

The masonry contractor, the hands-on professional who delivers the masonry wall system, is most assuredly today’s “construction need”. Few doubt the importance of masonry contractors - but many do not think about the potential for future depletion of this human resource. No, you won’t get LEED points for decisions that directly affect these men and women. Whether or not you are the purchasing agent, specifier or estimator (usually persons who do not actually perform the work of building the wall), you can help ensure the healthy longevity they richly deserve, and we need, as the “deliverer”.

Statistics show that where masons can get lightweight concrete masonry units - as defined by ASTM C 90 - they prefer to use them. As a recent paper acknowledged, “masons and contractors widely seem to prefer lightweight blocks”.4 No worry here since structural lightweight CMU, at equal compressive strengths, has greater strain capacity than the heavyweight units.5 If you would like more information on lightweight block made with structural-grade expanded shale and clay lightweight aggregate, contact me.

In these innovative times, new block wall systems offer higher R-values, high heat capacity (thermal mass), internal continuous membrane water and air barriers and enhanced impact resistance to name a few recent improvements. They can be designed for up to 200 mph hurricane force winds. The industry is responding like never before.

As a closing thought on sustainability, think about better thermal performance of the masonry wall. Also, consider how more lightweight aggregate is delivered per gallon of fuel to the block producer than heavyweight aggregate. And talk to your block manufacturer regarding how many additional blocks they can deliver per gallon of diesel to your next project, as opposed to the heavyweight units. The list of considerations goes on.

Stephen Stange
Sr. Sales Representative

Stephen Stange works for Texas Industries, Inc. (TXI) as a Senior Sales Representative in the Expanded Shale and Clay Lightweight Aggregate product group based in Houston, TX. Stephen has been a construction professional for the past 35 years, involved in real estate development, construction management, and the specification development process. He is certified by the National Concrete Masonry Association as a Certified Consultant of Concrete Masonry (CCCM) and is certified by CSI as a Construction Documents Technologist (CDT).

1 PCA, Concrete Thinker webpage, 2008

2 “Research Investigation of Masonry Productivity”, NCMA R&D Laboratory, reprint permission of MCAA

3 Rynold Kolkaski, Masonry Estimating, 1988

4 Rosecrance, J.C, “Effect of concrete block weight and wall height on electromyographic activity and heart rate of masons”, 2005 (Ergonomics magazine)

5 T.A. Holm, Block Concrete Is a Structural Material, Journal of Testing and Evaluation, July 1976

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Preventative Maintenance is a Hot Topic with Today’s $’s

Published by Kevin King on May 15, 2008 in Highways and Roads. 0 Comments

With today’s crazy material and fuel prices, rehab and new road construction is just not a viable option for many national and state agencies, from the federal level through the state, county and even city levels.  As a result, these government agencies are suggesting a well-rounded preventative maintenance program as the best way to extend the life of a road, as well as a budget. As you see in the chart below, any delay in maintenance (once the road starts its decline) can cost you much more in the long run. Ignoring the problem can cause base failures that result in expensive rehab and resurfacing.

What if you could extend the life of your road up to 10 years by doing more than twice as many lane miles at half the cost of rehabbing and overlays? Oh, and improve the skid resistance for better safety, deliver the aggregate in fewer trucks therefore reducing fuel costs, and give citizens an improved riding surface they can take pride in? Sounds like a ‘no brainer.’ That is what you get when chip sealing with expanded shale. Expanded shale particles do not polish but maintains its skid resistance as the aggregate wears.  The material can extend as much as 25% farther than heavy aggregates in road applications.  Its affinity for asphalt improves the bond between particle and asphalt, whether you use a hot asphalt cement or an asphalt emulsion. All of this adds up to better value for your tax dollars.

Let’s do some calculations to estimate a cost per mile assuming you use TxDOT Grade 5 Expanded Shale and asphalt emulsion:

5,280 ft. length x 24 ft. wide= 126,720 sq. ft. / 9 = 14,080 sq. yd.

14,080 sq. yd. / 125 (Grade 5 spread rate) = approx. 113 cu. yd. of Grade 5 Expanded Shale to shoot one mile

A .3 gal shot rate for asphalt emulsion = 4,224 gallons per mile

Aggregate Costs: $30 / cu. yd x 113  =  $3,390

Asphalt Costs: $1.75/gallon x 4224 = $7,332

Total: $10,772 material costs per mile.

Even those with a modest budget can begin a maintenance program and start improving their roads immediately. A $250,000 budget can get the materials to cover about 23 miles.

Kevin King
Highway Sales Manager

Prior to serving as highway sales manager at TXI ES&C, Kevin King spent 10 years with the Texas Department of Transportation (TxDOT) in construction and maintenance.  Additionally, Kevin has nearly five years of experience working in asphalt and emulsion sales, and more than six years of experience in aggregate sales and marketing.

Barrett Reese, Jr.
Highway Sales

Barrett Reese, Jr. joined TXI ES&C in 1998, initially selling expanded shale and clay specialty products that included Diamond Pro for sports fields and TruGro for horticultural applications. Two years ago, he moved to his current sales position in highway sales to work with TxDOT contractors, and county and city governments in the highway markets.  Barrett serves on the seal coat committee for TXAPA, the leadership and seal coat committees for AGC of Texas, and the asphalt committee for the national Expanded Shale, Clay & Slate Institute (ESCSI).

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When Every Game Counts

Published by Brad Garrison on April 25, 2008 in Diamond Pro. 0 Comments

Using vitrified clay to maintain infields
 
Managing moisture on a baseball or softball field’s skinned infield is critical because a wet infield can become unplayable and a dry infield will typically become hard, which makes sliding painful and can lead to dangerous groundballs.  Vitrified clay infield conditioners, such as Diamond Pro Red Infield Conditioner, provide moisture management benefits to a skinned infield. 

In wet situations, an infield conditioner will act as an absorbent layer helping an infield surface dry out more quickly. In dry conditions, an infield conditioner will act as a “mulch” layer helping reduce evaporation of moisture and, because vitrified clay infield conditioner won’t compress or stick to cleats, an infield conditioner will act as a barrier layer between a player’s cleats and the infield soil (infield dirt or infield clay).  Using vitrified clay infield conditioner as an amendment by tilling or nail-dragging into the soil helps improve drainage while also reducing compaction.

Texas Industries, Inc. (TXI) originally developed vitrified clay infield conditioners in the late 1980’s and early 1990’s by topdressing several Texas high school and college skinned baseball infields with rotary kiln lightweight aggregate (expanded shale and clay).  As the story goes, coaches had fewer rainouts and more games were played without postponement.  Finally, vitrified infield conditioners were accepted, and TXI created Diamond Pro. Diamond Pro Red Infield Conditioner was recently used to prepare the skinned infield at Wukesong Baseball Field (site of the 2008 Summer Olympic baseball games in Beijing, China) for exhibition games played between the San Diego Padres and the Los Angeles Dodgers in March 2008. 

Wukesong Baseball Field
Photo courtesy of Murray Cook

Because of ever increasing transportation costs, the ability to deliver vitrified clay infield conditioner in bulk is cost efficient compared to bagged products.  Most infield conditioning products, such as calcined clay infield conditioners, are usually packaged in 50 lb. paper bags, which typically require indoor storage space and higher freight costs in addition to the added cost associated with bagging the product.  Vitrified clay infield conditioners, such as Diamond Pro Red Infield Conditioner, can be stored outdoors year round without degradation because they are fired at temperatures exceeding 2000 degrees Fahrenheit and quickly cooled. This process creates an extremely durable ceramic particle that is significantly less susceptible to breakdown compared to other products commonly used to condition infields.  Bagged vitrified clay and calcined clay infield conditioners can be used to supplement the bulk vitrified clay infield conditioner, as necessary, to increase absorption potential of an infield in preparation of, or during, wet situations.

To learn more about vitrified clay infield conditioner products or for “How To” information and coverage charts, check out the Diamond Pro website or feel free to Ask the Pros. 

For an interesting read related to groundskeeping, check out Murray Cook’s Field Blog entitled “Ballparks & Ballfields From Around the World!”.

Brad Garrison
Sales – Diamond Pro
Texas Industries, Inc. - Sports Fields and Horticulture

Brad Garrison is a Diamond Pro sales representative.  He earned a bachelor’s degree in Landscape Contracting and Management from Mississippi State University and worked in the landscaping construction industry before joining TXI ES&C in 2005.  Brad’s education and experience in landscaping offers a unique understanding of various aspects related to sports field construction and maintenance.

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Using Expanded Shale for a Pedestrian Mix and Vehicular Mix

Published by Jack Sinclair on March 31, 2008 in Horticulture - Pave Grow. 0 Comments

(As a Growing Medium and Erosion Reduction Structural Soil for Emergency Access Areas, Overflow Parking, and Green Space Requirements)

Have you ever wondered what alternatives exist to using traditional concrete and asphalt for overflow parking areas or temporary access spaces? Many landowners and developers want to create a natural setting or “green space” that provides a stable, all-weather platform for vehicles in times of excess need or for emergency access. A natural setting offers tremendous aesthetic value and avoids the inherent problems of storm water run off and heat island effects. Expanded shale in a structural soil mix is the answer. It can be effectively used as a pedestrian or vehicular mix to serve as both an excellent growing medium for trees, grasses and landscape vegetation, as well as an erosion inhibitor for pedestrian and vehicular traffic.

View the images below to see how expanded shale works as a structural soil. Read about the recent Bella Mar project for a great example of how expanded shale was installed to create an overflow parking area at an amenity center near Austin, Texas.

Does anyone know if expanded shale as a structural soil would qualify as a LEED credit for pervious cover?

I welcome questions or comments about this product application.

Jack Sinclair

 Structural soil for emergency access
Structural soil in place since August of 2000 successfully providing emergency access across a golf course fairway. Click thumbnail for larger image.

Structural soil for fire lane
Structural soil as a fire lane since August 2003 at St. Edwards University, Austin, Texas. Click thumbnail for larger image.

Bio: Jack Sinclair has worked as a sales consultant on TXI Pave Grow® projects for the past 13 years and as a lightweight aggregate salesman with TXI for 17 years.  He has worked for TXI in other construction-related positions for 38 years, including Ready Mix Sales, Precast and Ready Mix Quality Control, and Ready Mix Logistics. 

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What’s Next for Concrete? Internal Curing

Published by Don Reeves on March 10, 2008 in Internal Curing. 0 Comments

If there is any such thing as a holy grail of concrete it has to be shrinkage cracks. The industry has conquered just about everything else. For example, we already make it stronger – 20,000 psi for columns, weaker for fill at 300 psi, lighter for insulating at 30 pcf, and heavier for radiation shielding at 180 pcf. We even make self-compacting concrete for easier placement and extra stiff concrete so it will stand up behind a slip form paver.

Wait, there’s more. We can make it set faster for quick repairs or slower for delivery to remote locations. We can make it beautiful for architectural appeal or plain ugly to be buried in the ground and never exposed to the light of day, while efficiently capturing and removing storm water run off before it can collect and cause millions of dollars in flood damage.

What’s left? How about crack-free concrete? I don’t doubt that someone can provide, without a minute’s worth of research, evidence of concrete that will out-perform the examples I have casually listed above, yet the problem of crack-free remains. Concrete shrinks and that irrefutable fact results in cracks that sometimes lead to reduced service life or costly repairs.

Can concrete that is cured from the inside out eliminate all shrinkage cracks? Probably not, but how about reducing cracks by almost half in 500 feet of mainline paving1 or how about 250,000 cubic yards of paving in an inter-modal yard that has to be studied on hands and knees to find a crack.2

Please visit the Menu for Internal Curing with Lightweight Aggregates for valuable internal curing resources.

For additional information about Internal Curing, read the white paper “INTERNAL CURING Using Expanded Shale, Clay, and Slate Lightweight Aggregate” published by Expanded Shale, Clay & Slate Institute.

Bio: The author is a long time practitioner in the concrete industry with over 38 years of experience in inspection, testing, production, quality control, and sales.

1 Friggle T.; Reeves D. “Internal Curing of Concrete Paving: Laboratory and Field Experience” ACI Fall Convention 2007 symposium

2 Villarreal V.H.; Crocker D. A. Better Pavements through Internal Hydration” Concrete International February 2007

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