Tekla Structures 21.1 SR8 Tekla, a leader in Building Information Modeling (BIM) software, has released Tekla Structures 21.1, the newest version of its BIM software.Models created with Tekla software carry the accurate, reliable and detailed information needed for successful Building Information Modeling and construction execution. Welcome smoother workflow to your company with Tekla Structures and constructable models. Tekla works with all materials and the most complex structures – you set the limits. Our customers have used Tekla Structures to stadia, offshore structures, plants and factories, residential buildings, bridges and skyscrapers.