The number of story and drift limitations on tunnel formwork shear wall buildings in earthquake prone regions

Tunnel form technique becomes more common practice for multistory residential reinforced concrete (RC) buildings with vertical structural systems consisting of shear-walls only in Turkey. Their earthquake resistance and ease of construction make them popular in the residential buildings. Although their seismic resistance is high, current seismic code provisions including UBC 97 (Uniform Building Code) and the Turkish Earthquake Code (TEC, 2007) present limited information about their design issues. There is no sufficient research work in the literature on the seismic behavior of tunnel form buildings. In this study, tunnel form residential buildings with 20, 25, 30 and 35 stories are considered, and their seismic behavior is studied parametrically. The buildings have the same layout with different number of stories, and there is symmetry in two directions. ETABS software is utilized to prepare 3D structural drawings. Structural designs of the buildings are carried out. Slabs are considered in the analysis by employing shell elements. In the seismic analysis of the structural system, mode superposition method is used. The story drifts, and the base shear profiles are calculated for the structural models. These results are compared to the requirements of the various design codes such as TEC 2007, EC8, and UBC 97..