Bridges, roads, tunnels, canals | Homeland Security Newswire

  • Earthquake-proofing precast buildings

    Precast or ready-made building structures offer a number of advantages when compared to more traditional construction techniques in terms of time and cost savings. The vulnerability of joints and connections between assembled precast elements, however, is widely recognized as a potential safety issue, especially in earthquake-prone areas. An EU-funded project has set out to develop new procedures and guidelines for designing precast structure joints and connections that can stand up to seismic forces.

  • U California, Berkeley students win National Student Steel Bridge Competition

    The weekend of 31 May residents of Washington State watched as engineers began erecting a temporary steel bridge over the Skagit River, to replace the 160-foot span of a 4-lane bridge that had collapsed a week earlier, after being struck by an over-height truck. Just sixty miles away, on the campus of the University of Washington in Seattle, 620 civil engineering students erected their own temporary steel bridges in a competition to demonstrate their engineering skills. For the second consecutive year and for the second time in the past seven years, a team of students from the University of California, Berkeley captured the title as champions of the ASCE/AISC National Student Steel Bridge Competition (NSSBC).

  • Thousands of U.S. bridges in “fracture critical” condition

    There are currently 66,749 structurally deficient bridges and 84,748 functionally obsolete bridges in the United States – about a quarter of the nation’s 607,000 bridges. With declining federal funds for bridge repair, the burden of maintenance has shifted to states, which spent $28.5 billion last year on bridge work – up from $12.3 billion in 1998.

  • Ash from olive residue biomass leads to more effective, cheaper concrete

    Researchers have produced self-compacting concrete with ash from boiler combustion of olive pruning residue pellets. The plasticity and cohesion of this type of concrete mean no compaction is needed when used in construction and, moreover, it has other advantages with respect to conventional concrete.

  • Helping bridges withstand natural disaster

    Structural control systems have the potential to help our civil infrastructure, such as bridges, roads, and buildings, withstand natural disasters such as earthquakes or storms. Traditional control systems based on sensors connected by wired networks, however, are costly, labor-intensive, and tend to break during disasters, when they are needed most.Wireless networks that are easier, cheaper, and more resilient to structural damage.

  • Larger fire-fighting crews save lives, limit damage in high-rise fires

    Between 2005 and 2009 there were, on average, 15,700 high-rise structure fires annually in the United States. Average annual losses totaled 53 civilian deaths, 546 civilian injuries, and $235 million in property damage. When responding to fires in high-rise buildings, firefighting crews of five or six members — instead of three or four — are significantly faster in putting out fires and completing search-and-rescue operations, concludes a major new study.

  • U.S. infrastructure grade raised from D to a D+, but problems loom

    The American Society of Civil Engineers (ASCE), in its just-released 2013 Report Card for America’s Infrastructure, gave the U.S. infrastructure an overall grade of D+, showing slight progress from the D in the last Report Card issued in 2009. The Report Card concludes that to raise the grades and get U.S. infrastructure to an acceptable level, a total investment of $3.6 trillion is needed by 2020. Currently, only about $2 trillion in infrastructure spending is projected, leaving a shortfall of approximately $1.6 trillion.

  • Building stronger, greener concrete with biofuel byproducts

    The world uses nearly seven billion cubic meters of concrete a year, making concrete the most-used industrial material after water. Even though making concrete is less energy intensive than making steel or other building materials, we use so much of it that concrete production accounts for between 3 to 8 percent of global carbon dioxide emissions.

  • New internally cured concrete increases bridge life span

    Concrete is normally made by mixing portland cement with water, sand, and stone. In the curing or hardening process, water helps the concrete mixture gain strength by reacting with the cement. Traditionally, curing is promoted by adding water on top of the bridge deck surface. The new technology for internal curing provides additional water pockets inside the concrete, enhancing the reaction between the cement and water, which adds to strength and durability. This new technology is enabling Indiana to improve bridges in the state with a new “internally cured” high-performance concrete.

  • New bridge construction technologies to shore up U.S. infrastructure

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    Experts agree that there is an urgent need to construct and repair bridges across the United States. Around 70,000 bridges in the country are considered “structurally deficient” by government standards. New technology could help the United States manage its growing, and aging, infrastructure without breaking the bank or levying high taxes on citizens.

  • NASA engineers building sturdy blue-collar mining robot

    After decades of designing and operating robots full of scientific gear to study other worlds, NASA is working on a prototype that leaves the delicate instruments at home in exchange for a sturdy pair of diggers and the reliability and strength to work all day, every day for years.

  • Improving cities by using the notion of “urban metabolism”

    As is the case with organisms, cities need energy, water, and nutrients, and they need to dispose of wastes and byproducts in ways which are viable and sustainable over the long run. This concept of “urban metabolism” is a model for looking systematically at the resources that flow into cities and the wastes and emissions that flow out from them in order better to understand the environmental impacts of cities and to highlight opportunities for efficiencies, improvements, and transformation.

  • The humble jute serves as a sustainable reinforcement for concrete

    Fashionable people may turn up their noses at jute, the cheap fiber used to make burlap, gunny sacks, twine, and other common products, but new research is enhancing jute’s appeal as an inexpensive, sustainable reinforcement for mortar and concrete.

  • 2002 Alaska earthquake helped set standards for buildings, bridges

    The Denali 7.9 earthquake that hit Alaska in 2002 was the largest to hit the United States in more than 150 years, and the strongest ever recorded in Alaska; no one was killed and only a few people were injured; the only severe damage the earthquake caused was to a few highways, but the damage was not significant enough to close them; the earthquake set new national standards for building bridges as well as giving seismologists a better understanding of how earthquakes affect frozen ground

  • Cooler pavement materials could increase energy consumption in surrounding buildings

    A push to replace old, heat-trapping paving materials with new, cooler materials could actually lead to higher electricity bills for surrounding buildings; the new paving materials are designed to lower the overall temperature of the areas where they are used