1960s1970s: Lin continued to expand his firm's specialty in prestressed concrete to broader consulting services, with projects that included conventionally reinforced concrete, structural steel, masonry, and timber-framed structures. In 1967, he designed the 18-story shear wall Bank of America building in Managua, Nicaragua. The reinforced concrete tower was one of only two structures left standing after the country's 1972 earthquake. Lin also became known for his design innovations, such as the Rio Colorado Bridge, an upside-down suspension bridge spanning a deep gorge in Costa Rica. In the early '70s, the firm also established offices in Taiwan and Singapore.