...
In the calculation for plastic deformations corresponding to ductile behavior, the deformation limits for new buildings and the deformation limits for existing buildings Plastic Deformation and Internal Force Limits for New Buildings and Plastic Deformation and Internal Force Limits for Existing Building differ due to the different material models. For this reason, these limit values are calculated automatically according to the selected building condition, compared with the plastic deformations and the building performance is determined. For internal forces opposing brittle behavior, ductility check of the elements is done for new and existing buildings.
According to TBDY 5.2.2.2 , if the Evaluation and Design Based on Strain (GDT) approach is applied to the structure, the earthquake calculation to be made with nonlinear calculation methods (any thrust analysis or nonlinear analysis in the time domain) should be E d (H) before Non -linear static calculation in which static vertical loads other thanwill be done. The internal forces and strains obtained from this calculation are taken into account as the initial value in the horizontal earthquake calculation. In this case, the non-linear static calculation applied using vertical loads is made according to the following loading condition. The internal forces and strains obtained as a result of this analysis are taken into account as the initial value of the horizontal earthquake calculation.
...
In the non-linear analysis in terms of geometry, second-order effects that occur due to the axial forces occurring in the building elements are taken into account. Second-order effects are divided into p-δ and p-Δ. The figure on the right shows how the effects of p-δ and p-Δ are on an element in a representative way. The p-δ effect is caused by the axial pressure force on the element trying to increase the displacement plasm caused by the element's own curvature. The p-Δ effect, on the other hand, creates additional moments in the axial pressure force due to the displacements of the nodal points of the element. p-Δ is explained in more detail in the picture below.
...
Yığılı Plastik Davranış ModeliYayılı Plastik Davranış ModeliConcentrated Plasticity Model Distributed Plasticity Models
In order to consider the second order effects p- p and p-Δ effects, the analysis is done by dividing the elements sufficiently. In this way, the modified system at the initial or any i th step of the pushover analysis is considered as the initial condition for the next step. The following image shows the analysis model and the modified system, considering the second-order effects of a sample model.
...
No labels
LikeBe the first to like this