Meeting the quality level called for in the Panama Canal's new locks while producing the massive volume of concrete required to finish the job by the expected fall 2014 completion date has called for extreme equipment solutions. For each primary process—batching, conveying and placing—the material is tightly controlled.
The sheer volume of concrete—more than five million cubic meters—has to be built to meet the structures' projected century-long life span. As a result, the quality standards for the concrete are extremely high. The entire lock worksites on the Atlantic and Pacific sides—measuring about 1,400 meters long, 120 m wide and 45 m deep—boast a concrete batch plant engineered and manufactured by Italy's SIMEM. Each plant is designed to handle about 610 cu m per hour, with 10 dedicated scales to handle the five aggregate types required by the primary concrete specifications.
Because it can moderate the damaging effects of earthquakes, base-isolation is a technique used primarily in seismically active regions. ENR takes a look at some of the largest applications of base-isolation technologies in the world.