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Impact energy tests are an efficient method of verifying adequate toughness of steel prior to it being put into service. Based on a multitude of historical correlations between impact energy and fracture toughness, minimum impact energy requirements that correspond to desired levels of fracture toughness are prescribed by steel bridge design specifications. Research characterizing the fracture behavior of grade 485 and 690 (70 and 100) high-performance steel utilized impact, fracture toughness, and crack arrest testing to verify adequate performance for bridge applications. Fracture toughness results from both quasi-static and dynamic stress intensity rate tests were analyzed using the most recently adopted master curve methodology. Both impact and fracture toughness tests indicated performance significantly greater than the minimum required by material specifications. Even at the AASHTO Zone III service temperature, which is significantly colder than prescribed test temperatures, minimum average impact energy requirements were greatly exceeded. All master curve reference temperatures, both for quasi-static and dynamic loading rates, were found to be colder than the Zone III minimum service temperature. Three correlations between impact energy and fracture toughness were evaluated and found to estimate reference temperatures that are conservative by 12 to 50 °C (22 to 90 °F) on average for the grades and specimen types tested. The evaluation of two reference temperature shifts intended to account for the loading rate was also performed and the results are discussed.

More than half of the world’s human population lives within 40 miles of the sea. Coastal cities are the backbone of global finance, trade, manufacturing, and transportation. Millions of people worldwide travel to beaches for recreation. Coastal fisheries and aquaculture are key sources of food, and the chief source of protein in most developing countries. The coast is home to a diverse range of plants and animals, some commercially valuable, some threatened or endangered, and all part of unique ecosystems. Coastal livelihoods, tourism, fish and wildlife species, and ecosystem services are threatened by climate change and its associated impact on coastal hazards. Flooding and coastal disasters from New York to Kolkata have killed thousands of people and cost trillions of dollars. By 2100 more than 100 million people could be displaced by sea-level change, 13 million in the U.S. alone. The stability of the global economy is threatened by sea-level change...

More than half of the world’s human population lives within 40 miles of the sea. Coastal cities are the backbone of global finance, trade, manufacturing, and transportation. Millions of people worldwide travel to beaches for recreation. Coastal fisheries and aquaculture are key sources of food, and the chief source of protein in most developing countries. The coast is home to a diverse range of plants and animals, some commercially valuable, some threatened or endangered, and all part of unique ecosystems. Coastal livelihoods, tourism, fish and wildlife species, and ecosystem services are threatened by climate change and its associated impact on coastal hazards. Flooding and coastal disasters from New York to Kolkata have killed thousands of people and cost trillions of dollars. By 2100 more than 100 million people could be displaced by sea-level change, 13 million in the U.S. alone. The stability of the global economy is threatened by sea-level change...