The 92nd annual meeting of the Transportation Research Board (TRB) was held earlier this month in Washington, DC. About 11,500 transportation professionals attended the conference, 4% more than last year’s attendance. More than 4,800 papers were presented. Following is an update of the sessions and meetings attended by NRMCA:

• Two ½ day workshops were held on Service Life Modeling, and Advances in Preventing and Mitigating Alkali-Aggregate Reactivity.
• Like last year, there were several papers on surface resistivity.  The test is more economical than the RCPT test (ASTM C1202). It is a lot easier and quicker to do and has excellent correlations with RCPT but with lower variability. AASHTO TP 95-11 is a provisional standard. Aggregate size, type, curing environment affects the results. A paper was presented where it was shown that the typical jobsite testing variability in temperature was ±5°F. A paper was present by FHWA on the ruggedness testing of the CTE test (AASHTO TP 336) where it was shown that saturation can be a significant parameter affecting test results. FWHA reported that 17 bridges in the U.S. now use Ultra High performance concrete (UHPC) which is defined by ACI AS concrete with a specified strength over 22,000 psi and meeting specified durability and tensile ductility. Presentations were shown where nano silica and nano alumino silicates can be used for early strength gain as well as preventing ASR.
• TRB’s Nanotechnology Task Force has recently developed a circular E-C170 on Nanotechnology in Concrete Materials. This circular can be downloaded here.
• TRB’s Durability Committee has recently updated its circular on concrete durability. This circular should be available from the TRB Web site by next month.

The theme for the 2014 TRB meeting is Celebrating the Legacy and Anticipating the Future.