Modeling in RFEM
During the modeling, you have to enter the cable as a continuous polyline with at least three nodes. Thus, the program "knows" that the entire cable is an element. Then, you can assign the "Cable on Pulleys" member type to this polyline. At least one end of the cable member must have a fixed support or a member, so that the applied tensile load can be transferred. Since the tensile force should be constant in the "cable on pulley", no further definition is necessary for the connected elements. The adjacent elements or nodal supports receive deflection forces if there is buckling on the cables.
When modeling, rigid members were applied in such a way that the slab force can be displayed on a support. Additional stabilizing supports were arranged on the loose pulleys to counteract the instability.
The required pulling distance was applied by means of an imposed nodal deformation.
KB 001658 | Modeling of Factor Pulleys in RFEM
Create guidelines with or without a description for the display of a building grid! You can lock the guideline position to prevent accidental movement of them, for example.
Furthermore, you can glue the guidelines to nodes in order to move the glued nodes as well. That makes your work a lot easier!
Go to Explanatory VideoThe pushover analysis is managed by a newly introduced analysis type in the load combinations. Here, you have access to the selection of the horizontal load distribution and direction, the selection of a constant load, the selection of the desired response spectrum for the determination of the target displacement, and the pushover analysis settings tailored to the pushover analysis.
In the pushover analysis settings, you can modify the increment of the increasing horizontal load and specify the stopping condition for the analysis. Furthermore, it is possible to easily adjust the precision for the iterative determination of the target displacement.
- Consideration of nonlinear component behavior using plastic standard hinges for steel (FEMA 356, EN 1998‑3) and nonlinear material behavior (masonry, steel - bilinear, user-defined working curves)
- Direct import of masses from load cases or combinations for the application of constant vertical loads
- User-defined specifications for the consideration of horizontal loads (standardized to a mode shape or uniformly distributed over the height of the masses)
- Determination of a pushover curve with selectable limit criterion of the calculation (a collapse or limit deformation)
- Transformation of the pushover curve into the capacity spectrum (ADRS format, single degree of freedom system)
- Bilinearization of the capacity spectrum according to EN 1998‑1:2010 + A1:2013
- Transformation of the applied response spectrum into the required spectrum (ADRS format)
- Determination of target displacement according to EC 8 (the N2 method according to Fajfar 2000)
- Graphical comparison of the capacity and required spectrum
- Graphical evaluation of the acceptance criteria of predefined plastic hinges
- Result display of the values used in the iterative calculation of the target displacement
- Access to all results of the structural analysis in the individual load levels
During the calculation, the selected horizontal load is increased in load steps. A static nonlinear analysis is carried out for each load step until reaching the specified limit condition.
The results of the pushover analysis are extensive. On one hand, the structure is analyzed for its deformation behavior. This can be represented by a force-deformation line of the system (a capacity curve). On the other hand, the response spectrum effect can be displayed in the ADRS display (Acceleration-Displacement Response Spectrum). The target displacement is automatically determined in the program based on these two results. The process can be evaluated graphically and in tables.
The individual acceptance criteria can then be graphically evaluated and assessed (for the next load step of the target displacement, but also for all other load steps). The results of the static analysis are also available for the individual load steps.
For example, can I define a member that absorbs all internal forces, except for the compressive axial forces?