5.5.1 Nonlinear Calculation - Ultimate Limit State

Nonlinear Calculation - Ultimate Limit State

The table in the upper part contains the governing safety factors and utilizations determined in the nonlinear ultimate limit state design for each cross-section, member, or set of members. They result from the internal forces, the reinforcement parameters, and the specifications set in the Settings for Nonlinear Calculation dialog box (see Figure 4.4 and Figure 4.6).

The lower part lists all Detailed Results for the table row selected above. The design details are updated when clicking into another row.

With the All load cases check box, you can decide whether to only show the results of the governing action or (as shown in Figure 5.33) the results of all analyzed load cases and combinations.

The safeties and design ratios are listed by cross-sections.

The x-locations refer to the FE nodes that have been created on the members for the nonlinear calculation. Use the [Details] button in the Iteration Parameters tab of the Settings for Nonlinear Calculation dialog box (see Figure 2.30) to access the FE Mesh dialog box of RFEM where you can adjust the FE mesh settings.

This column displays the numbers of the load cases or load combinations that are governing for the individual cross-sections, members, or sets of members.

If several load cases or combinations have been designed, it is possible to show the results of all analyzed actions by selecting the All load cases check box.

The column lists the safety factors γ for each location x. They represent the ratio of ultimate and acting internal forces.

$\gamma = \frac{R_d}{E_d} \ge 1.0$

where

$R_d=\left|\begin{array}{c}{N}_{Rd}\\ M_{y,Rd}\\ M_{z,Rd}\end{array}\right| \text{design value of load-bearing capacity}$

$E_d=\left|\begin{array}{c}{N}_{Ed}\\ M_{y,Ed}\\ M_{z,Ed}\end{array}\right| \text{design value of action}$

If the safety factor at any x-location is less than 1, or if no convergence is reached, the ultimate limit state design is not fulfilled. The entire table is presented in red color.

The entries in this column represent the safety factors' reciprocal values γ. Thus, you can quickly evaluate the resources in the cross-section.

The Detailed Results in the lower part of the window (see Figure 5.34) provide information about all design details. They are organized in a tree structure.

The detailed results are adjusted to the selected Tension Stiffening Approach (see Figure 4.6).

The final column refers to failed designs or specific situations occurring in the course of the design (e.g. when the maximum number of iterations was reached in the final load step of the calculation without fulfilling the break-off criterion). The numbers are explained in the status bar.

Use the [Messages] button to display all issues that have occurred in the nonlinear calculation.