Trade Journals for the Concrete Industry

… using advanced batching system The 6.8 magnitude Nisqually earthquake that struck eastern Washington State in 2001 shook a wide area of the U.S. Northwest, damaging numerous structures including many roads and bridges. The damage and subsequent repairs of a 1950s era reinforced concrete double- decker highway led to an ambitious replacement plan that includes the world's largest diameter highway tunnel. On July 30th, an $80 million tunnel boring machine (TBM) departed its 80-foot deep launch pit near the Seattle waterfront. The TBM – the world's largest – arrived in April 2013 from Osaka, Japan, and its 41 pieces were lowered into the launch pit for assembly. At speeds of up to 35 feet per day, the earthworm-like TBM will burrow its way below nearly 200 buildings and a maze of subsurface infrastructure for nearly two miles, surfacing just south of Lake Union in the fall of 2014.