摘要
With only 18 floors,Mjøstårnet,a ruddy blonde building in Brummundal,Norway(Fig.1),is dwarfed by modern skyscrapers.It is not even the tallest building in Norway.But the structure,which includes offices,apartments,and a hotel,stands out for another reason—it is built almost entirely of wood[1].Instead of the usual steel or concrete,the building’s beams,columns,and trusses are made from glulam,produced by gluing pieces of wood together with the grain in parallel[2].The lower floors,walls,stairs,and elevator shafts are also constructed of wood[3].Only the floors of the upper stories,which contain the apartments,are concrete to increase stability and improve acoustics[4].For three years after its completion in 2019,the 85.4 m Mjøstårnet was the world’s tallest timber building,but the Ascent MKE tower in Milwaukee,WI,USA,which opened in mid-2022,is just over 1 m taller[5].More than 1300 other so-called mass timber buildings,which substitute engineered wood products such as glulam for steel and concrete,are currently under construction in the United States alone[6].
