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When deformed configuration is derived through input parameters (main cable sag, main cable span, deck profile, etc.), the corresponding force values may be obtained using SAP2000. Analysis may begin with coordinates which specify the final deflected shape. The cable load which corresponds to the final deformed configuration should be specified in the Cable Geometry menu. This cable load can be estimated from the weight of the structure and its distribution along the bridge.
After analysis, joint coordinates should be modified through Analyze > Modify Undeformed Geometry such that deflected shape at the end of staged construction matches the geometry initially specified. Several iterations may be necessary for convergence to the desired shape.
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