Houston bridges are crumbling

Alkali-silica reaction (ASR) is invading Houston bridges. For years, the state of Texas was immune to the attack that destroys the structural integrity of the spans, but recently there has been a flood of cases, and it may cost the Houston Toll Road Authority $30 million to fix.

Just recently the Harris County Commissioners Court expanded a $175,000 contract with local engineering consultant Walter P. Moore to develop a preventive maintenance plan for ASR on the tollway system’s 30 bridges and 107 miles of concrete.

At a meeting back on Aug. 11, commissioners sought bids for a $504,000 project to repair cracked concrete on connector bridges on the Westpark and Sam Houston tollways, and a $1.2 million contract is already in place for a bridge over the Houston Tollway at U.S. 290 following repairs completed in January 2008 to an older bridge connecting I-45 south to the Hardy Toll Road that cost over $468,000.

The ASR problem is not limited to the Houston area either. The Texas Department of Transportation estimates that about 1,000 bridges are infected with the problem.