Product Development
Product development continues at Bethlehem Steel's Homer Research Laboratories in Bethlehem, Pa. to develop an "as-rolled" or thermo-mechanical controlled processed (TMCP) HPS-70W steel for bridges. The goal is to eliminate the need for quenching and tempering, thereby permitting the processing of longer plate lengths. This production route will reduce the number of splices required and lower initial plate cost. Current trials at BLP's 160-inch mill in Burns Harbor have demonstrated the capability of producing a TMCP HPS-70W to 1-1/4in. (32 mm) thick. Evaluation and development of TMCP steel through 3 in. (76 mm) is also continuing. These developments are being shared with the FHWA-AISI-Navy HPS Steering Committee. Initial use of TMCP HPS-70W will require owner/bridge engineer approval until steel specifications are modified.

Specification Coverage
ASTM A709/A709M - Structural Steel For Bridges - has been revised by ASTM to include coverage for Grade HPS-70W (HPS 485W). This revision is available as A709/A709M-97b^e1, and it provides owners and fabricators a convenient way to specify and order HPS-70W without complicated special provision documents.

Stock Availability
HPS-70W plate stock is available from one or more steel service centers. For more information on stock availability and locations, please call 800-966-5352.

Summary
Valuable experience is being gained through use of cost-effective HPS-70W steel plate girders on FHWA bridge demonstration projects, as well as owner projects. Availability of TMCP HPS-70W, plus broader mill production and fabrication experience, will lead to significant cost savings for steel bridges.

Design Support
To optimize the use of HPS-70W, bridge designers may want to refer design-related issues to BLP's Construction Marketing Team.