CarbonCast in Carbon Fiber Gear blog

The good people at the Carbon Fiber Gear blog -- one of the leading resources for what's hot with carbon fiber applications -- have featured information about CarbonCast and carbon fiber reinforcing in precast concrete in their latest post. Check it out.

Wall panel test video

Under the supervision of Dr. Sami Rizkalla and Gregory Lucier at the Constructed Facilities Laboratory at North Carolina State University, the AltusGroup Technical Committee tested recently completed a 50-year test of a 42-foot-long CarbonCast HPIWP. The panels consisted of two 6-foot wide wythes of prestressed concrete, each 2 inches thick, bonded to an inner 4” thick layer of expanded polystyrene (EPS) foam. Carbon fiber grid was used to connect the two wythes of concrete at selected locations to achieve composite action. The panel was tested oriented horizontally in a rig that allowed for the application matching lateral loads at the quarterspans. The panel was oriented on its edge to prevent selfweight from influencing the lateral loading behavior.

Reverse-cyclic lateral loads were applied to simulate the effects of wind pressure and suction. The panel was subjected to nearly 4,000 cycles of reverse-cyclic fatigue at 45% of the factored lateral load. Following the fatigue regime, lateral loads on the panels were increased to failure.

In general, the tested panel behaved elastically to load levels close to the factored design load of 1.6W. A high degree of composite action was observed at all load levels, and beyond the elastic stage, the panel exhibited a very ductile load-deflection response. The carbon fiber grid shear transfer mechanism proved effective in maintaining the structural integrity of the panel even at high levels of overstress.

Advances in cement

Excellent article today in the New York Times about technological advances in cement production and use in concrete. Of course, concrete reinforcing has also been advancing with the use of carbon fiber grid.

Carbon accounting methods

Here's a good article from Architectural Record about efforts to "place more emphasis on reducing carbon emissions and mitigating global warming" in the various building rating systems worldwide. A unified worldwide standard is not imminent, but the cooperation will likely lead to some consistency in objectives, measurement and language.

Innovative precast research

Dr. Sami Rizkalla -- one of the technical advisors to AltusGroup -- is heavily involved with precast concrete research. A release from North Carolina State University explains spandrel designs that use less reinforcing steel. In coming weeks, Dr. Rizkalla will conduct research for AltusGroup on a new wall panel design that will offer additional insulation properties in a strong but lightweight configuration.

ENR: new green-concrete technology announced

An article in ENR discusses a new technology that makes cement from flue gas and seawater, rendering a new type of concrete that sequesters carbon without disturbing its traditional binder: portland cement. Read more.

Carbon fiber grid at World of Concrete

AltusGroup member Chomarat NA will showcase the advanced composite reinforcement technology that has made the company one of the world’s leading innovators in precast development, custom reinforcement products and structural grids using carbon fiber, fiberglass and aramid technology. The company invites industry professionals interested in learning more about these and other valuable reinforcement technology solutions to visit Chomarat’s World of Concrete booth (S13451) during the event. Chomarat will provide product literature, recent project profiles and new product information. Read the entire news release from Chomarat.

Versatility of carbon fiber

Thought this was interesting -- Yo Yo Ma will be playing a carbon fiber cello at the inauguration ceremony. It's just more evidence of a material technology that's becoming increasing mainstream.

Winchester (Va.) Garage melds classic look with carbon fiber precast technology

The past and the future are coming together in Virgina.

Winchester’s charming Kent Street is getting a new $7.68-million parking garage melding aesthetics that reflect the city’s historic architecture with construction technology that represents the leading edge in precast concrete.

AltusGroup precaster Shockey Precast Group used CarbonCast Pretopped Double Tees in the engineering, manufacturing and erection of the 540-space garage. In Reed Construction News, Shockey Project Manager Gary Ball said:

The precast includes C-GRID carbon fiber grid reinforced double tees that help make the structure lighter and stronger. Stainless steel fasteners are being used on the project. Both the carbon fiber and the stainless steel are non-corrosive, thus eliminating what is often a parking garage owner's biggest maintenance headache — problems relating to corrosion.

Read more>>