Footing with pedestal and washer plate anchors
1 New project
Start by launching the IDEA StatiCa application. In the main window of IDEA StatiCa, open the Detail application to define a new project.
Select the Model Type - 3D -> Class - General ->Parameters and Initial Settings, and Create the model.
2 Geometry
To start with modelling, you select Model Entity and Solid Block.
The standard cuboid pops up, with the definition of its dimensions being Width - X, Depth - Y, and Height - Z, which is related to the GCS (Global Coordinate System). The system of nonconformities in the 3D scene (left top corner) will notify you of what is missing to initiate a successful analysis.
The Negative Volume represents the cut-off part that intersects the original volume.
Define the dimensions of Negative Volume->Surface - 1 ->Edge - 3 -> Local Z-position - 2.5 m. The transparent mode depicts the negative volume.
The Operation - Cut denotes the Boolean operation known as subtraction. This process effectively removes the portion of the original segment based on its negative-volume geometry.
The original volume SB1 is Cut by NV1.
Utilize the Negative Volume NV1 and Copy the operation. Once you copy the operation, switch on the Edge-4. The NV2 will be shifted to the symmetry position and aligned accordingly.
Copy the operation CUT1 and set NV2 as the cutting attribute.
Upon creating NV3, it is imperative to adjust the Depth to 0.75 meters and reallocate the Surface numbering to 2.
Cut the original volume by NV3.
The last step is to duplicate NV3 to make NV4. Change the Surface and Edge, then set it to number 4.
Copy the operation CUT3 and reapply the NV4 as the cutting volume.
The final geometry of the concrete part. Transition point for upcoming chapters.
3 Supports
The Surface Support is the only option for restraining the structure.
The support system provides three degrees of freedom. The surface support provides separate stiffness inputs in all three directions. These parameters have a crucial influence on the overall model behavior.
The vertical stiffness 15 MN/m3 for this example is derived from the article on the web. You assume "Fine or slightly compacted soil". For an overview of the applicable value range, the table is provided as a reference.
The horizontal stiffness of the surface support matters. If the stiffness is perfectly rigid, the bending reinforcement in the first layer of bars near the soil-concrete interface experiences almost zero stress.
The second extreme scenario arises when horizontal stiffness is set to a very low level. This adjustment results in pronounced body movements induced by shear forces.
The optimal horizontal stiffness for the current case has been determined for value 1 MN/m3.
The support is automatically assigned as Inactive in tension (numbered 1/greyed-out button). To activate the stiffness definition, click the Pen icon (numbered 2).
4 Design
The Base Plate is the fundamental element for stub, anchors, and mortar layer.
The base plate shall be securely positioned onto the Mortar joint, with nuts applied from both the top and bottom. The thickness of the layer is specified as 50 mm. Shear forces will be effectively transmitted through the anchors, while the column, an IPE 500 profile, is rotated 90 degrees around its local axis.
The column section is used to redistribute the forces into the base plate appropriately. How the forces are transferred, attached, and specified is imprinted here.
To connect the base plate and concrete part, you need to define the Single anchor and specify its properties.
The Cast-in-place method, incorporating Washer plates at the end of the anchors, has been chosen. By default, the anchors are designed to transmit both tension and compression forces, as well as shear forces. The X and Y coordinates of the anchor set out accordingly.
From this point forward, the X-coordinates of the anchors will be adjusted solely to establish a series of anchors on one side. Using the Copy button to duplicate anchors is strongly recommended to expedite the process.
To efficiently replicate the predefined series of anchors, utilize the multi-selection feature for streamlined execution.
The multi-selection functionality facilitates the bulk modification of the Y-coordinate to -0.09 m, thereby significantly accelerating the design process. These proficient tips and techniques are designed to enhance efficiency in your workflow.
Anchoring with mortar joints, stubs, and anchors with washer plates is complete, ready for the next phase.
5 Load effects
Define the Load Case and select the action via the Point Loads.
Concentrated forces are applied at the origin of the LCS location and transmitted via rigid elements to the member's end. As the steel component isn't evaluated in the 3D Detail, verify the member and base plate with IDEA StatiCa Connection or similar tools to avoid excessive loads on steel part. As the secondary load, assign the concrete block's Self-weight. Copy the entire load case.
The software primarily works with combinations, rather than individual load cases. Combinations must be explicitly defined. This model uses ULS combinations LC1 and LC2 as load cases, integrated in the combination tab with a partial factor of one.
The combinations are compounding the loads from existing load cases to initiate the analysis. The nonlinear solution confidently operates with the loads, and it is essential to precisely sum them up.
6 Reinforcement
The reinforcement configuration adheres to the prescribed detailing standards. These standards are of paramount importance, as the analysis does not account for specific effects. For instance, phenomena such as shrinkage and hydration heat induce additional strains and stresses in the reinforcement bars, contributing to the formation of cracks.
The following section outlines the steps for the reinforcement layout of the entire footing with a pedestal. Follow the steps (1). You can deactivate the rebars in the ribbon (2) to see only selected rebars. It will help you intuitively recognize each group.
Final layout of reinforcement bars is ready for Calculation.
7 Check
In this chapter, you enter into the post-processing, where the results are summarized and presented. The results are easy to understand and mostly tailored for code-check. Detailed and comprehensive results can be discovered in the Auxiliary tab.
Run the calculation and observe the summary check. These results give you a clear pass/fail.
The first detailed check is focused on the Strength - Concrete. If you utilize the scalable stress palette, the critical spot will be easy to detect.
The second check is devoted to Reinforcement, where it is clearly outlined which bars are subjected to compression and tension.
The Anchors are code checked separately in the last tab. You can observe that anchors are loaded up in tension and compression. The reason is due to the selected system - Cast-in-place/Mortar joint with nuts/ washer plates.
The Deformation verification has been relocated to the Auxiliary tab. It is worth noting that deformation analysis should serve as the initial sanity check to ensure that the behavior aligns with anticipated outcomes.
8 Report
At last, go to the tab Report. IDEA StatiCa offers a fully customizable report to print out or save in an editable format.
You have successfully completed the design and assessment and gained the skills to use it in your daily routine work. Keep it up and boast about it on your socials.