• California dams plagued by seismic concerns

    Half of Santa Clara County, California’s reservoirs cannot be filled to their full capacity due to seismic concerns; engineering tests revealed that in the event of a major earthquake the dam could slump sending a deadly tidal wave across densely populated communities; seismic retrofit costs to the county’s dam are estimated at $150 million; with the reduced capacity, the county’s dams must be maintained at 67 percent of its total capacity and cannot store more water in preparation for future droughts; the lost capacity could provide water for 280,000 people for a year

  • Securing the California Delta's levees before a major earthquake

    In the event of a major earthquake or flood and many levees failing simultaneously in California’s Sacramento-San Joaquin River Delta, as many as 515,000 residents and 520,000 acres of land would be in immediate danger; the long term effects could be even more widespread, as nearly 28 million residents depend on the Delta for water and irrigation; California lawmakers have increasingly turned their attention to securing the Sacramento-San Joaquin River Delta’s levees, but experts say that only little progress has been made

  • Louisiana worried about Corps' levee armoring plans

    Louisiana says the Corps of Engineers is $1 billion short for completing levee construction around New Orleans, while the Corps says it has enough money; the disagreement over the cost of completing levee construction centers on a long-simmering argument over the last construction task scheduled for earthen levees throughout the system: deciding what type of armoring will keep the levees from washing away if they are overtopped

  • China's Three Gorges Dam's showing cracks

    The Three Gorges Dam is China’s largest construction project since the Great Wall; the dam was hailed as an engineering feat that could withstand the worst flood in 100 years, but this year’s torrential rains have severely tested its capacity to control the surging Yangtze

  • Rubber dam at Tempe Town Lake bursts, emptying lake overnight

    An inflatable rubber dam (called “bladder”) on Tempe’s Town Lake exploded, sending a wall of water into the Salt River bed; at least three-quarters of the about one billion gallons of water had drained overnight; those parts of the rubber dam which are wet have held up, but a plan to keep those parts of the dam which are above water failed, exposing the rubber to scorching sun that has damaged the material

  • Berkeley quake demonstration shows bridge safety ideas

    Researchers demonstrate new bridge design that can withstand powerful earthquakes; the design concept relies on building segmented bridges with seismic isolators between the segments; the design would be particularly useful for long stretches of elevated freeways and high-speed rail lines that often run on elevated tracks

  • Self-healing concrete developed

    University of Rhode Island researchers develop a new type of self-healing concrete that promises to be commercially viable and have added environmental benefits; a microencapsulated sodium-silicate healing agent is embedded directly into a concrete matrix; when tiny stress cracks begin to form in the concrete, the capsules rupture and release the healing agent into the adjacent areas

  • How to protect Times Square -- and other highly traveled areas

    New Yorkers were lucky that a T-shirt vendor notices the suspicious SUV left by Faisal Shazad in Times Square, but there are ways to improve on luck in trying to secure highly traveled areas; more coordinated CCTV system, blast-mitigation, and more call boxes are a few of the measures

  • Remotely controlled robot inspects dangerous structures

    A remotely controlled robot uses laser sensors to look inside damaged structures to look for survivors; when inside the structure, the robot takes multiple scans using Light Detection and Ranging (LIDAR) unit that takes up to 500,000 point measurements per second. It also can scan through walls and windows

  • New California tremor map shows 50 new faults

    California has an estimated 15,000 faults; many of those are short, and experts have found no evidence that they have generated sizable temblors; others, though, can produce major quakes; the state’s geological agency have placed fifty new faults — all of them surface faults that have been discovered over the last two decades — on one map which will help educate the public and aid in planning and quake readiness

  • Protecting structures by tracking down rust

    Damage to concrete bridges caused by rust can have fatal consequences, at worst leading to a total collapse; now, researchers have developed an early-warning system for rust; sensor-transponders integrated in the concrete allow the extent of corrosion to be measured

  • The lessons of Chile earthquake to California building code

    Since the Chile earthquake, many U.S. engineers have visited Santiago and other affected cities to study the failures and successes of building codes here; Chile is of particular interest to American engineers because it employs similar building codes to those in California and also has widespread use of reinforced concrete; one observation from Chile’s earthquake that could find its way into U.S. building code concerns confining reinforcement; confining reinforcement is meant to keep vertical bars from bucking, but the design proved insufficient in Chile; one solution: requiring confining reinforcement along a greater length of the wall

  • Detecting structural defects with wind and water

    Bridges, aircraft, and wind turbines are in constant movement; natural forces and pedestrians all create vibrations; previously, time-consuming tests were needed to determine how building components would react to vibrations; now, researchers have developed a simpler method

  • Chile's concrete code for buildings called into question

    Since 1985, some 10,000 buildings three stories or higher were built in Chile — constructed in compliance with a strict building code introduced after a power earthquake which rocked the country; only 1 percent will have to be demolished as a consequence of the magnitude-8.8 earthquake that struck on 27 February; still, engineers who inspected the damage in many of the bearing-wall concrete frames of 12- to 26-story buildings say the damage calls into question the effectiveness of Chile’s building code, which does not require confinement reinforcing steel for concrete members

  • Washington State, federal officials in dam-related disaster resilience exercises

    Officials from the Tri-Cities area of Washington State, neighboring areas, and federal agencies participate in a exercise aiming to develop a strategy to improve disaster resilience and preparedness in the event of severe flooding along the Columbia River, flooding which leads to overtopping and subsequent breaching of levees in the Tri-Cities area