Additional Uniform Dead Load
Input an additional uniform dead load. This load is applied to the one foot wide culvert structural model. In other words, to convert an area load to the proper distributed load, simply multiply by 1 foot.
Future Wearing Surface
Input the weight of a future wearing surface (if any), which is also applied to the one foot wide culvert structural model.
Neglect Live Load
LL will be neglected in the analysis if any of the selected criteria is met.
Live Load Surcharge
Approach Slab: If an approach slab will be used, live load surcharge will be neglected from the analysis
Compute Depth of LL Surcharge: For the LRFD specification, the user can select this option to let the program calculate the height of the live load surcharge depending on the fill depth and the height of the culvert. Where the user has selected to analyze a range of fill depths, the value of the live load surcharge will also change.
Depth of LL Surcharge: Input the value for the depth of the live load surcharge. This value will be used for all fill depths.
Applying Surcharge for fills > 2 ft: Normally the program only applies a live load surcharge when the fill depth is less than 2 feet. By selecting this option you can force the program to apply live load surcharge at all fill depths. If you want to force the program not to apply any live load surcharge for fills less than 2 feet, then set the depth of the live load surcharge equal to zero.
Applying Surcharge when LL is Neglected: Select this option to have that analysis apply loading due to live load surcharge even when live load is neglected due to any of the user-defined criteria.
Equivalent Fluid Pressures
For LRFD, STND and CHBDC, input the maximum and minimum equivalent fluid pressures for lateral earth loads. The default for the maximum is 60 psf, and the default for minimum is 30 psf. The maximum value will be used in those load combinations where the program is calculating the maximum inward pressure on the walls, and the minimum is used where the program is calculating the minimum inward pressure (or maximum outward pressure). The exceptions are LRFD 5th Edition, where the program matches the perceived intent of the 1st Edition of the MBE, and uses the minimum load factor, EHmin, to calculate the minimum inward pressure, and CHBDC, which uses EHmin as well.
Lateral Pressure Coefficients
For AREMA, assign the maximum and minimum lateral pressure coefficients.
Consider Internal Water Pressure
Select this option to have analysis consider internal water pressure. Internal water is assumed to have a unit weight of 62.4 pcf.
Interior Pressure Head
Input the pressure head you would like applied to the interior of the culvert. Pressure head is measured from the bottom of the top slab.
Example Interior Pressure Heads | Applied Loads |
|---|---|
Pressure head = 0 ft The box is full, therefore the load is triangular. |  |
Pressure head = -3.0 ft The box is partially full, therefore the load is triangular. |  |
Pressure head = 3.0 ft The load is trapezoidal. |  |
Consider External Water Pressure
Select this option to have analysis consider external water pressure. External water is assumed to have a unit weight of 62.4 pcf.
Exterior Pressure Head
Input the pressure head you would like applied to the exterior of the culvert. Pressure head is measured from the middle of the top slab.
Example Exterior Pressure Heads | Applied Loads |
|---|---|
Pressure head = 0 ft The load is triangular, extending from the middle of the bottom slab to the middle of the top slab. |  |
Pressure head = -3.0 ft The load is triangular, and assumes the ground water does not extend up to the top slab. |  |
Pressure head = 3.0 ft |  |
Check Buoyancy
If this option is selected, Eriksson Culvert will perform a buoyancy check.
Include Seismic Loads
Select this option if you would like Eriksson Culvert to perform a seismic analysis.
Direction of Motion
Users have the ability to select horizontal, vertical, or both.
Seismic Force Combination
User have the ability to determine how seismic forces are combined, either:
1.0H + 1.0V
0.3H + 1.0V and 1.0H + 0.3V
where “H” is results of the horizontal seismic analysis and “V” is results of the vertical analysis.
Effective Peak Ground Acceleration
Enter the peak ground acceleration in the horizontal direction.
Ground Shear Modulus
Enter the ground shear modulus.
Slip Interface
Select the slip interface, the options are “no slip” and “full slip”.
Additional Uniform Loads
Users have to option of including additional vertical and horizontal uniform loads to the culvert analysis. The uniform vertical load will be applied to the culvert’s top slabs, and the uniform horizontal load will be applied to the culvert’s exterior walls. To enable these options, use the check boxes ‘Include additional horizontal load’ and ‘Include additional vertical load’.
For each of these loads, you will be required to input a magnitude and load type (dead, live, or earth). The load type determines with load factor will be applied.
Concentrated Dead Loads
Input up to three additional concentrated line loads. For each load, input the magnitude of the load and the location from the centerline of the left most wall.
Inverted Three-Sided Wall Loads
For inverted three-sided culverts, the ability to add wall loads will be enabled in a new tab. This allows users the option to add vertical and horizontal point loads (with or without eccentricities) to the top of the culvert walls.