Concrete beam with an opening

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In this tutorial, we will go step by step through modeling and code-check of a part of a concrete beam with a circular opening.

1 New project

Beam with an opening - New project

Start a New project in IDEA StatiCa Detail.

In the Discontinuity Region Wizard, set the concrete and reinforcement grade and define the Concrete cover thickness. Select the Member 1D template.

Beam with an opening - New project

Select the topology of the discontinuity region – Opening.

Beam with an opening - New project

2 Geometry

Start the definition of the Geometry by changing the cross-section of the M1 member.

Beam with an opening - Geometry

Define the I shape with haunched flanges.

Beam with an opening - Geometry

Change the width of the flanges and the height of the beam.

Beam with an opening - Geometry

The opening is enlarged and shifted to the center of the beam.

Beam with an opening - Geometry

3 Load effects

Now, move to define the Load of the detail. You can see that two load cases and three combinations were already created. Change the content of the load cases a little bit.

Beam with an opening - Loads

For LC1 (permanent load), change the Internal forces so that you input the values of shear force and bending moment at the point of the opening.

Beam with an opening - Loads

Similarly, change the values of internal forces for LC2 (variable load).

Beam with an opening - Loads

In Load Impulses, keep the value of line load to -10 kN/m in global Z-direction for LC1.

Beam with an opening - Loads

In Load impulses of LC2, change the value to -5 kN/m in global Z-direction.

Beam with an opening - Loads

The nonlinear combinations were already defined: C1 stands for ULS checks. C2 is a quasi-permanent and C3 a characteristic load combination, both defined for SLS code checks (see the tab Load cases & Combinations). The partial coefficients for the combination rules can be adjusted as well.

As you do not need to evaluate the individual load cases, they are unchecked which implies that they will not be analyzed. The calculations will be performed only for the checked items (combinations C1, C2, and C3).

Beam with an opening - Loads

4 Reinforcement

Once the load has been defined, you can proceed to Input/Edit the reinforcement. You will exploit the items created by the template.

Beam with an opening - Reinforcement

You can change the diameter of stirrups and adjust their distances (first value corresponds to the distance of the first stirrup from the edge, the other stirrups will be distributed in distances given by the second value).

Beam with an opening - Reinforcement

Reduce the diameter of bars of reinforcement RO1 around the opening and also the number of layers of horizontal/vertical and also diagonal bars.

Beam with an opening - Reinforcement

The operation GB1 includes a group of bars at the bottom face of the beam. Change the diameter of bars.

Beam with an opening - Reinforcement

5 Calculation and Check

Proceed to calculate the project. Continue to Check in the navigator and press the Check button it the top ribbon.

Beam with an opening - Check

In the left bottom table, you can see the overview of all the code checks and the status of the checks (passed/failed).

In the table in the middle, all the detailed results can be found. At the moment, the resulting strength check of the concrete in ULS is presented. In the top ribbon, the limit value for the diagram can be changed. You changed the value so that only the concrete in compression over -2 MPa is marked red.

Beam with an opening - Check

By changing the top tabs, you can display all the code checks. In the Summary, the main results for ULS/SLS are presented. Click on the line in ULS/Anchorage length to display the utilization of the bond between concrete and reinforcement (with the most critical spot marked in the figure).

Beam with an opening - Check

We open the SLS results by selecting, e.g., the line SLS/Stress limitation line in the table.

Beam with an opening - Check

To open the detailed results of ULS, change the tab to Strength. As noted above the table, C1 combination was used to check ULS.

Beam with an opening - Check

Again, you can display the results for Concrete and also for Reinforcement by selecting the corresponding line in the table. You can select any bar of reinforcement to see its results of analysis and code check.

Beam with an opening - Check

The results of SLS are located in tabs Stress, Crack, and Deflection. For the Stress limitation state, the C2 combination was governing to check the concrete, while C3 to check the reinforcement.

Beam with an opening - Check

Calculated crack widths can be displayed in the Crack tab (combination C2). The calculated values are compared to the limit value w_{st,lim} that can be edited in the top ribbon.

Beam with an opening - Check

6 Report

At last, go to the Report Preview/Print. IDEA StatiCa offers a fully customizable report to print out or save in an editable format.

Beam with an opening - Report
Beam with an opening - Report

You have designed, optimized and code-checked the part of the beam with an opening.

Sample files

Beam with an opening

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