Function
- Define dead loads and live loads of the bridge
Call
From the main menu, select [Structure] tab > [PSC Bridge] group > [Prestressed Composite Bridge]
Input
Fig. Prestressed Composite Bridge Wizard Load dialog box
Pavement and Barrier
Refer to the following diagram for b1, b2, b3, b4, b4 & b5.
Fig. Definition of symbols
b1 : Left barrier width. The barrier load is applied over the barrier width.
b2 : Carriageway width (left). The wearing surface load is applied over the carriageway width.
b3 : Median strip width. The median strip load is applied over the median strip width.
b4 : Carriageway width (right). The wearing surface load is applied over the carriageway width.
b5 : Right barrier width. The barrier load is applied over the barrier width.
P1 : First and second positions of additional load.
P2 : First and second positions of utility load.
Deck : Define or select the material applied to the upper Deck.
Dead Loads
When each loads are checked off, the program does not generate the data for the load case.
Equally to All Girder
DC(Before Composite) : DC load case before the composite action will be distributed equally to all girders.
DC(After Composite) : DC load case after the composite action will be distributed equally to all girders.
DW(Before Composite) : DW load case before the composite action will be distributed equally to all girders.
Fig. Applying to 'Equally to All Girder'
Before Composite
Self Weight : Self weight
Wet Con'c : Weight of wet concrete. Load is generated on the concrete weight density and deck thickness.
Weight Density : Weight density of concrete.
Thickness : Thickness of upper slab.
Form Work : Weight of form works
The Wet concrete and Form workloads should be input with the unit of force per length square. For Wet concrete, Weight density multiplied by thickness makes force per length square
All frame modeling type: The load value is calculated with each deck width and applied to each girder as an element beam load
Deck as Plate modeling type: The load value is applied as a pressure load
S.I.P forms : Click to apply S.I.P forms instead of normal formwork. S.I.P forms will be applied as loading and it will remain in place after the wet concrete is hardened.
Fig. Wet concrete load case
After Composite
Barrier : Weight of the lane barrier.
Median Strip : Weight of the median barrier/strip installed to separate the traffic lanes.
The Barrier, Median Strip magnitudes should be entered in the unit of force per linear length.
All frame modeling type : This load value is applied over the entire bridge length at the deck ends as nodal loads.
Deck as Plate modeling type : This load value is applied as pressure loads.
Fig. Barrier load case
Additional load : Weight of the additional point load. The position is defined by the value entered. Use the above diagram as a reference.
Basically, the distance (P1) is the distance from the reference axis to the first additional load. Multiple locations can be entered and separated by commas. The distance to each location is measured from the left end of the bridge cross-section.
Additional load magnitudes should be entered in the unit of force per linear length.
This load value is applied over the entire bridge length at the deck ends as nodal loads.
Wearing surface : Weight of the wearing surface (e.g. asphalt) covering the bridge road. The load magnitude should be entered in the unit of force per length square. (Weight density multiplied by wearing thickness)
All frame modeling type : This load value is calculated with each dummy deck spacing distance and applied to each transverse deck as an element beam load.
Deck as Plate modeling type : The load value is applied as a pressure load.
Utilities : Weight of the utility point load. The position is defined by the value entered. Use the above diagram as a reference.
Basically, the distance (P2) is the distance from the reference axis to the first Utilities load. Multiple locations can be entered and separated by commas. The distance to each location is measured from the left end of the bridge cross-section.
The Utilities load magnitude should be entered in the unit of force per linear length.
This load value is applied over the entire bridge length at the deck ends as nodal loads.
Fig. Wearing surface load case
Live Loads
Check on to define Live Loads
Define Moving Load Case : Select the moving load code to be used in the analysis
Define Traffic Line Lane
No. of Lanes : Number of lanes on the bridge. Use the diagram and the table (No. vs. Distance) to define the lane locations.
The distance to each lane center is measured from the left end of the bridge cross-section.
Each lane width is automatically defined based on the moving load code selected before entering this “Define Traffic Lane”. Based on the Moving Load Code and Traffic Lane information, the program automatically creates the vehicle lane data.
Define Vehicles : To enter new or additional vehicle loads. Vehicle loads can be either selected from the standard or manually defined as the “user-defined” type.