A rapid-hardening mix promoted for fast formwork removal, Promptis is the charter offering in a family of branded ready mixed products Cemex, S.A.B. de C.V., envisions for its worldwide markets. Dosed with proprietary admixtures, the new material reaches early compressive strength in as fast as four hours, compared with an average of 18 hours in conventional concrete.
Read MoreDay: May 6, 2011
ACI Adhesive Anchor certification fulfills tunnel tragedy-rooted NTSB request
Responding to an unusual National Transportation Safety Board cue, American Concrete Institute will launch the Adhesive Anchor Installer Certification in early summer, just ahead of the ACI 318-11 Building Code Requirements release.
Read MoreFCC-filled, carbon-fiber tube bridge system gains DOT, ASCE traction
A carbon fiber reinforced polymer composite arch tube product—pumped with ready mixed on site and geared to 20- to 80-ft. span bridges—has landed the American Society of Civil Engineers’ 2011 Charles Pankow Award for Innovation. Dubbed Bridge-in-a-Backpack by Advanced Infrastructure Technologies (AIT), the 12- or 15-in.-diameter FRP tubes bear ⅜-in. aggregate mixes with superplasticizers dosed to impart self-consolidating, concrete-level spread characteristics. As superstructure components, the hardened tubes provide what engineers note are corrosion protection and external concrete reinforcement in lieu of conventional rebar.
Read MoreReport cites $70 billion tab for bridge repair and replacement backlog
One in nine bridges and overpasses is rated in poor enough condition that they could become dangerous or be closed without near-term repair, according to a Transportation for America report “The Fix We’re In For: The State of the Nation’s Bridges.” Nearly 70,000 crossings nationwide are rated “structurally deficient” and need substantial repair or replacement, authors contend, while the Federal Highway Administration estimates that the backlog of potentially dangerous bridges would cost $70.9 billion to clear—versus a current federal outlay just over $5 billion per year.
Read MoreOSH, Davis-Bacon Acts Bring Taxpayers Divergent Returns
As the Occupational Safety & Health Administration marked its 40th anniversary at the end of April, agency officials pointed to an impressive two-thirds reduction in workplace fatality rates since 1970 (report, OSHA timeline, page 14).
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