Applying Supports (Boundary Conditions)

1. Activate the Support Tool: Select the Support option from the Loads & Constraints toolbar to open the SPC (Single Point Constraint) dialog.
2. Select Nodes and Degrees of Freedom: Choose the required nodes and specify translational (UX, UY, UZ) and rotational (ROTX, ROTY, ROTZ) constraints. Use Fix All or Pinned options as needed.

   Options available:

   • Select Joints on Ground → Automatically select joints lying on the ground level (XOZ plane)

3. Add the Constraint: Click the Add button to assign the defined support condition to the selected nodes.

   Options available:

   • Edit → Modify an existing constraint

   • Remove → Delete a constraint

4. Verify and Close: Confirm the constraint details in the SPC table and close the dialog to apply the supports to the model.

Self-Weight:

Using self-weight command, the weight of the structure is added as Dead Load. Dead loads remain constant over time and are considered to be acting continuously on the structure.

Uniformly Distributed Load (UDL):

A UDL is a load that is evenly distributed along the length of the beam. It applies a constant force per unit length.

1. Select the UDL Load Type: From the Loads & Constraints toolbar, click on Loads and choose UDL to open the uniformly distributed load definition dialog.
2. Select the Beam: Choose the beam element on which the UDL is to be applied. The selected beam is highlighted in the model view.
3. Define Load Extent: Specify the start (D) and end (D1) distances along the beam length to control the region over which the UDL is applied.
4. Specify Load Components: Enter the distributed load values in the required directions: WX, WY, and WZ (force per unit length).
5. Select Coordinate System: Choose either Local or Global coordinate system for defining the load direction.
6. Add and Verify: Click Add to apply the UDL. Verify the load details in the load table and confirm the load visualization on the beam.

Point Load:

A point load is a concentrated force that is applied at a specific point on the beam. It can be represented as a single force acting downward or upward.

1. Select the Force Load Type: From the Loads & Constraints toolbar, click on Loads and select Force to open the concentrated force definition dialog.
2. Choose Load Location: Select whether the force is applied at a Joint or on a Beam. For beam loads, specify the position along the member length.
3. Define Force Components: Enter the force values in the required directions: FX, FY, and FZ. Positive and negative signs control the load direction.
4. Select Coordinate System: Choose between Local or Global coordinate system for force direction definition.
5. Add the Load: Click Add to assign the force to the selected joint or beam location.
6. Verify Load Assignment: Confirm the applied force in the load details table and verify the graphical representation in the model view.

Moment:

A concentrated moment is a rotational force applied to the beam. It causes bending and twisting of the beam about a particular point.

1. Select the Moment Load Type: From the Loads & Constraints toolbar, click on Loads and select Moment to open the concentrated Moment definition dialog.
2. Choose Load Location: Select whether the Moment is applied at a Joint or on a Beam. For beam loads, specify the position along the member length.
3. Define Moment Components: Enter the Moment values in the required directions: MX, MY, and MZ. Positive and negative signs control the load direction.
4. Select Coordinate System: Choose between Local or Global coordinate system for Moment direction definition.
5. Add the Load: Click Add to assign the Moment to the selected joint or beam location.
6. Verify Load Assignment: Confirm the applied Moment in the load details table and verify the graphical representation in the model view.

Temperature Load:

The Temperature Load in IMDAS simulates the effect of thermal expansion or contraction in structural members due to temperature variation. This load induces axial strain based on the defined temperature change and material properties, and is critical for accurate analysis of structures exposed to environmental temperature effects.

1. Open Load Definition
   Go to the Loads & Constraints tab in the IMDAS ribbon menu.
2. Select Temperature Load
   Click on Loads and select Temperature from the drop-down menu.
3. Choose Member Selection Mode
   Select either All Members or Select Members based on the required application.
4. Enter Temperature
   Specify the temperature (T) of the member.
5. Assign the Load
   Click Add to apply the temperature load to the selected members.
6. Verify Load Application
   Confirm the applied temperature load in the model view and load details panel.

Seismic Loads:

IMDAS computes seismic parameters as per IS 1893:2016, allowing users to select zone, soil type, structure category, damping ratio, and response reduction factors. It automatically evaluates base shear, seismic mass, horizontal coefficients, and other key inputs needed for safe and code-compliant structural design.

1. Select Seismic Load: From the Loads & Constraints toolbar, click on Loads and select Seismic to open the seismic load definition panel.
2. Define Seismic Parameters: Enter the required IS 1893 input parameters including:
   • Zone and Zone Factor (Z)
   • Soil Type (Rock / Hard / Medium / Soft)
   • Structure Type and Importance Factor (I)
   • Response Reduction Factor (R)
   • Damping Ratio (%)
3. Specify Structural Periods: Provide the fundamental natural time periods in the X and Z directions, either manually or using code-based estimation.
4. Define Load Data: Assign seismic mass by specifying:
   • Self-weight factor
   • Joint weights: Select joints and add mass
   • Member weights: Select members and add mass
5. Calculate Seismic Forces: Click Calculate to compute base shear and lateral forces as per IS 1893 provisions.
6. Review Seismic Output: Verify the calculated results such as:
   • Total seismic mass
   • Base shear forces (X and Z directions)
   • Horizontal seismic coefficients
   Click Close to finalize the seismic load definition.