This tab allows the user to check column stresses and insert loads at multiple stages. Each analysis stage assumes a minimum of two reactions.
Stripping and handling contains four optional stages for stripping, handling, erection, and a secondary erection. The face lifter input and top edge lifter input do not change the analysis results, only modify the model and reported reactions. Their inputs are:
Header | Description |
|---|---|
Columns of Lifters | Number of lifting devices at each lift point, and is used for calculating lifter forces and for the |
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3D drawing. |
Top in Form | Select from Bottom, Top, Left, or Right Face for the top in form face. |
Stripping
The stripping stage is removing the member from the bed or casting bed or table.
Face Loops
Number of lift points used during stripping.
Load Multiplier
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The four optional analysis stages contain the following options:
Header | Description |
|---|---|
Face Loops | The quantity of face loops on the member. |
Dunnage Points | The quantity of dunnage points on the member. |
Load Multiplier | A multiplier to be applied to all self weight. |
Lift Type | Static Lift |
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This type of lift assumes that each lift loop is a separate line, attached to a rigid frame (basically a statically indeterminate model).
Rolling Block
This type of lift assumes that only one crane line is used, and each pair of lift loops is connected to a single line passing through a roller.
Concrete Strength
Initial
Concrete strength at stripping.
In-Place
Concrete strength at final (typically at 28 days).
Stress Limits
Transfer
Limits on the tension and compression stresses at stripping (transfer of the prestress force to the column).
In-Place
Limits on the tension and compression stresses at final (when all loads have been applied).
Sling Angle
Minimum sling angle allowed during handling (degrees). This value is only used to calculate the shear at the face of the column for each insert.
Lifter Locations (from bottom)
Location of the lifters. These inputs will be reset if you click the ‘Set to Default Locations’ button.
Set to Default Locations
When clicked, moves the lifting inserts to locations will be calculated per the fractions recommended by PCI.
Transportation
The transportation stage is moving the member around the precast yard or to the job site. This stage assumes a static lift.
Dunnage Points
Number of dunnage points used during shipping or storing the member.
Load Multiplier
Factor applied to self-weight to account for dynamic forces encountered during shipping.
Concrete Strength
Initial
Concrete strength at stripping.
In-Place
Concrete strength at final (typically at 28 days).
Stress Limits
Transfer
Limits on the tension and compression stresses at stripping (transfer of the prestress force to the column).
In-Place
Limits on the tension and compression stresses at final (when all loads have been applied).
Dunnage Locations (from bottom)
Location of the dunnage points. These inputs will be reset if you click the ‘Set to Default Locations’ button.
Set to Default Locations
When clicked, moves the lifting inserts to locations will be calculated per the fractions recommended by PCI. You can also select to set the dunnage locations at the same locations as the stripping devices.
Erection (Primary/Secondary)
Both primary and secondary erection stages are treated exactly the same. This format simply allows the user to include two erection stages in the same file, so if you are switching crane lines or boundary conditions during erection you do not have to make two runs. This stage always assumes a rolling block analysis.
Face Loops
Number of lift points used during stripping.
Load Multiplier
Factor applied to self-weight to account for dynamic forces encountered during erection.
Tilt Angle
Angle that the analysis is performed. Eriksson Column does not do a rotation analysis.
Concrete Strength
Initial
When selected, the program will use the initial concrete strength (f’c) for the calculation of flexural strength and service load stresses at time of erection.
In-Place
When selected, the program will use the final concrete strength at this stage.
Stress Limits
Transfer
Limits on the tension and compression stresses at stripping (transfer of the prestress force to the column).
In-Place
Limits on the tension and compression stresses at final (when all loads have been applied).
Sling Angle
Minimum sling angle allowed during handling (degrees). This value is only used to calculate the shear at the face of the column for each insert.
Lifter Locations (from bottom)
Location of the lifters. These inputs will be reset if you click the ‘Set to Default Locations’ button.
Set to Default Locations
When clicked, moves the lifting inserts to locations will be calculated per the fractions recommended by PCI. You can also select to set the dunnage locations at the same locations as the stripping devices.
Add Ground Reaction
Add a ground reaction to the boundary conditions used the this analysis stage.
Add Edge Lifters
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: Will assume all lift locations act as a pin. Rolling Block: Will assume a sling is run between sets of connectors. This sling normalizes forces between connectors. The forces are normalized between for an entire crane line. For example, if doing a 4-high lift using 2 crane lines, the first two lifters will have the same reaction and the second two lifters will have the same reaction. Where if one was doing a 4-high lifting on a single crane line, all 4 lifters would have the same value. | |
Tilt Angle | The angle to tilt the member for the analysis. |
Concrete Strength | Option to use either the release strength or the 28-day strength of the concrete. |
Stress Limits | Option to use either the handling stress limits or the in-place stress limits. |
Sling Angle | Angle used to compute the lateral force at a given lifter. This value will not effect the analysis and will only be used to estimate the shear force a connector is exerting on the panel. |
Add Ground Reaction | Option to add an a ground reaction on the member. If the ground reaction ends up being negative (in tension), consider removing the ground reaction. |