- Specify the analysis conditions for a heat of hydration analysis.
- midas Civil follows the procedure noted below for a heat of hydration analysis.
1. Select Model > Properties > Time Dependent Material(Creep/Shrinkage) and Model > Properties > Time Dependent Material(Comp. Strength) to specify the time dependent properties. And then link the general material properties and time dependent material properties in Model > Properties > Time Dependent Material Link.
2. Enter the relevant data necessary for the heat of hydration analysis in the sub menus of Load > Heat of Hydration Analysis Data.
3. In Analysis > Heat of Hydration Analysis Control, specify the temporal discretization factor, initial temperature, location of stress output and whether or not to include Creep and Shrinkage.
4. Select the Analysis > Perform Analysis menu or click Perform Analysis to carry out the analysis.
5. Once the analysis is completed, check the analysis results in contours, graphs and animation.
From main menu, select [Analysis] tab > [Analysis Control] group > [Heat of Hydration]
Heat of Hydration Analysis Control dialog box
Specify a stage to be considered as the final construction stage of the heat of hydration analysis.
Assign the last stage as the true last stage.
Assign a stage within the overall construction stages as the final stage. Analysis will be performed only up to the Stage specified here.
Enter the Temporal discretization Factor, Φ used in heat transfer analysis.
Φ = 0 : Forward difference
Φ = 1/2 : Crank-Nicolson method
Φ = 2/3 : Galerkin method
Φ = 1 : Backward difference
Specify the initial temperature used in the heat transfer analysis.
Element Stress Evaluation
Specify the location in solid elements for stress output.
Center : Use the stresses at the centers of the solid elements to represent the stresses of the individual elements.
Gauss : Use the stresses at the Gauss points as the nodal stresses.
Nodal Point : Interpolate the stresses at the Gauss points for nodal stresses.
Creep & Shrinkage
Account for Creep and Shrinkage in the analysis.
Select one of the options for inclusion of creep and shrinkage in the analysis.
Creep Calculation Method
Creep calculation method can be selected between the code-based method (General) and the effective modulus method. If the General method is chosen, the creep and shrinkage will be considered based on the code input in the Time Dependent Material (Creep/Shrinkage) section. The effective modulus method is an approximate calculation method proposed in the Concrete Standard Specification (1996), which modifies the elastic modulus to account for creep.
1. In case General is selected
Convergence for Creep Iteration
Specify the convergence requirement for ending the repetitive process in the analysis reflecting creep.
Number of Iteration : Maximum number of repetitions
Tolerance : for convergence
2. In case Effective Modulus is selected
To apply a reduction factor phi1 to the elastic modulus from 0 (day) to n1 (day), and a reduction factor phi2 after n2 (day), the reduction factor between n1 and n2 is interpolated and used.
If a file from a previous version that includes creep data defined by the Effective Modulus method is loaded, the creep-related data will be deleted. Therefore, you need to redefine the creep data.
Use Equivalent Age by Time & Temperature
Select whether or not to use Equivalent Age based on Time and Temperature for Heat of Hydration Analysis.
Include Selfweight Load
Check this option to include Selfweight. Enter "-1" to consider the selfweight in the gravity direction.
Remove Hydration Analysis Data
Remove the hydration heat analysis condition. In this case, the hydration heat analysis will not be performed.