Lateral Load Distribution in Precast Buildings: A Parametric Study in FEM-Design

Abstract

Finite element modeling is crucial in analyzing complex structures, yet accuracy relies on realistic input data. This thesis investigates the influence of modeling assumptions on structural behavior and load distribution in precast concrete buildings. A parametric study was conducted using the commonly employed software FEM-Design. A virtual building, comprising shear walls, hollow core slabs, beams, and columns, served as the testbed. Parameters were systematically altered across five categories: slab configuration, wall-slab connection, horizontal wall connection, vertical wall connection, and endpoint behavior of edge connections. The effects were evaluated in both one-story and 10-story building models. The analysis revealed significant differences in deformations between the models due to changes in parameters, consequently affecting load distribution. Parameters had a more pronounced effect on load distribution in the one-story building compared to the 10-story building. This was mainly attributed to the relative stiffness of the floor diaphragm and shear walls. In upper stories, walls were relatively flexible due to large deformations. Consequently, the impact of parameter variations on shear distribution was reduced as the relationship between the walls and the floor remained consistent, with the floor acting as the rigid component. Lower stories tended to feature more flexible floors compared to the shear walls. Since the building in the analysis had irregularly placed shear walls, it was prone to rotation. This rotation was most pronounced in the models that had the most rigid floor diaphragm. Changes in connection stiffness between slabs had minimal impact, while the horizontal connection between walls notably affected building deformations. The vertical connection between walls had a substantial impact on both deformations and load distribution due to the coupling of shaft walls to a c-section. In conclusion, this study highlights the intricate relationship between modeling assumptions and structural performance in precast concrete buildings. It emphasizes the need for careful parameter consideration in finite element modeling to enhance safety and reliability.