Steven Holl Architects’ Experimental “Crinkle Concrete”

Developed for Washington DC’s John F Kennedy Center for Performing Arts, Steven Holl Architects’ experimental “crinkle concrete” treatment gives walls in the new expansion, known as The Reach, the appearance of crumpled paper. More than an aesthetic development of an ancient material, the cast-in-place concrete diffuses sound and offers additional acoustic support in performance spaces. In a detailed interview with CityLab, Garrick Ambrose, the project …

Why 2,000-Year-Old Roman Concrete Still Stands

How is it that 2000 years later, certain Roman ruins still stand in harbors? Geologists have determined that it pertains to one of the components—aluminum tobermorite, a rare mineral found in volcanic ash. When struck with seawater (another component of Roman concrete, along with lime and rock), a possolanic reaction occurs where the tobermorite crystallizes and spreads—adding further strength. Thus, longterm seawater exposure only reinforces …