In the task, we determined the characteristics of the seismic response of rectangular reinforced concrete walls and the effect of their connection with reinforced concrete slabs, without beams. These types of walls are usually designed as cantilever walls. In such cases, we usually assume that the only »connection« between the walls are constraints in the horizontal direction at floor level (rigid diaphragms). In other words, we ignore the bending stiffness and load-bearing capacity of the connecting slabs, assuming that it is negligibly small compared to that of the walls. In the assignment, we made a parametric study, where we analyzed whether this assumption is justified and how it is affected by various geometric and structural parameters. In the analyses, we took into account the provisions of the standards Eurocode 8 and Eurocode 2. The walls were first dimensioned based on the results of the linear elastic modal analysis. Considering that with such an analysis we can only determine the approximation of the seismic response of the considered structures, we also evaluated their seismic response with a non-linear analysis, in which we used the N2 method. The considered wall constructions represented a characteristic part of typical wall buildings. In one case, we treated the walls as cantilever walls, and in the other as connected walls. The logitudinal reinforcement of these two systems did not differ significantly in the cases considered, because in the case of connected walls, a significant part of the overturning moment is absorbed by the moments caused in the construction by the axial forces in the walls. Due to the different redistribution of bending moments along the walls, the transverse forces were quite different. As a result, the required transverse reinforcement in connected walls were in most cases significantly greater than in cantilever walls. In the slabs, in the case of connected walls, the bending moments were mostly very large and, as a result, a relatively large amount of longitudinal reinforcement was required. We also found out that the degree of connection of walls only with the slabs can be very high. A key role in this is played by the participating width of the slab, which is activated in the case of a strong seismic response and can be significantly larger than what is usually taken into account in the design. This parameter also significantly affects the type of response mechanism that is activated in the nonlinear region.
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