to complete the definition of the bridge model.Use the Pier Bent Data 1, Pier Bent Data 2, or Pier Bent Data 3 forms to describe the bent geometry and cap properties for the bridge. The modulus of elasticity of the bent cap and the columns making up the bent are also described on the Pier Bent Data 1 form. The column properties are described on the Pier/Column Type form.
TIP: After defining the bent data, click the Define menu > Columns command or the Define Columns button to complete the definition of the bridge model.
Pier Bent Data 1 parameters.
Bent ID column. This is the program assigned ID for the bent.
Elevation Top, Elevation Bottom columns. Specify the elevation in feet at the top and the bottom of the column. Both values must be entered. A zero length column (i.e., difference in elevations = zero) is not permitted. The elastic column length is computed as the difference between these elevations. These elevations must be consistent with the abutment elevations specified on the Overall Geometry form.
Bearing column. Enter the bearing (Deg, Min, Sec) of the centerline of the bent. The bearing may be specified in either direction. When no bent bearing is given, it will be assumed to be normal to the superstructure centerline (radial on curved alignment). Bearings resulting in 90 degree skews (i.e., bents parallel to the superstructure) are not permitted.
No of Columns column. Specify the number of columns in the bent. A maximum of 99 columns per bent is permitted.
Equal Col. Spacing column. Select equal or unequal column spacing by selecting Yes or No from the drop-down list.
Column Spac./Loc. column. These data are required for bents having more than one column.
Equal Column Spacing: Specify the distance in feet between the column centerlines along the centerline of the bent. Specifying a column spacing for a single column bent will cause the problem to be rejected.
Unequal Column Spacing: By clicking the respective cell, a list box will be displayed along with two command buttons (the checkmark and the OK), as shown below.
Column locations are displayed in the list box. To edit any location, click on it in the list to highlight it; the highlighted location will appear in the text box at the top of the list where it can be overwritten by typing directly into the cell. Click the Accept button 
to store the edited value. After editing all column locations, click the OK button to close the list box.
Modulus E column. Specify the modulus of elasticity for the bent.
Column Type column. Specify the column type numbers to be recalled for use in the bent. (See the Pier/Column Type form.) Note that only one column type may be used in each bent.
Bent Cap Data
Mon. Inertia Cap Beam Iz and X-Section Area Cap Beam columns. Enter the moment of inertia (ft4) for normal bending (i.e., in the plane of the bent caused by vertical loads) and the cross sectional area (ft2). Note that the moments of inertia about the X and Y axes are assumed by the program. The moment of inertia about the X axis (i.e., torsion) and the moment of inertia about the Y axis (i.e., bending in a plane parallel to the super structure deck) are assumed to be 10,000 times Iz. Stiffness about these two axes is usually considerably larger because of the presence of the superstructure surrounding it. This effect is approximated by increasing the two moments of inertia by the factor given above.
Length of Cap Beam column. Enter the cap length in the transverse direction of the bridge along the cap.
Pier Bent Data 2 parameters. Load acting on the bent are described on this form.
Bent ID column. This is the program assigned ID for the bent.
Wind on Column (Long) and (Trans) column. Enter column wind forces or use the default values.
Centrifugal Force H Load (Trans), (Long), (Norm) and Centrifugal Force P Load (Trans), (Long), (Norm) columns. Enter the value of the centrifugal force if one is required because the program does not provide a default value for the force. The program calculates the moments associated with the centrifugal force using the structure depth defined on the Deck Span Data 1 form. If all six values are omitted, the program will not generate the loading cases. Enter centrifugal forces by the different loading conditions, i.e. the force associate with different live load conditions, maximum longitudinal moment, maximum transverse moment, and maximum axial force at the bent.
Pier Bent Data 3 parameters. The bent support conditions are described on this form.
Bent ID column. This is the program assigned ID for the bent.
Top Column - Column Releases at Top
Top Column Moment Releases - Release X, Y, Z columns. The options on this form provide control over all of the moment releases in the column. The releases are applied in the plane of the bent and apply to all of the columns in the bent. Indicate the column fixity by selecting from the drop-down list. If a moment release for torsion is specified at both top and bottom, a program override is invoked, fixing the top in order to avoid an unstable condition.
Foundation - Column Releases at Bottom
Force Releases - Foundation Spring Kz, Kx, Ky columns. The options on this form provide control over all of the force releases at the bottom of column. The releases are applied in the plane of the bent and apply to all of the columns in the bent. Indicate the column fixity by selecting from the drop-down list. In addition, spring constants can be fixed or free at the bottom of the column.
Moment Releases - Foundation Spring Mz, Mx, My columns. The options on this form provide control over all of the moment releases at the bottom of column. The releases are applied in the plane of the bent and apply to all of the columns in the bent. Indicate the column fixity by selecting from the drop-down list. In addition, spring constants can be fixed or free at the bottom of the column.
See Also
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Access the Pier Bent Data 1, Pier Bent Data 2, or Pier Bent Data 3 forms as follows:
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and choose the