# Suspension Bridge Wizard

## Presentation on theme: "Suspension Bridge Wizard"— Presentation transcript:

Suspension Bridge Wizard
Analysis Control Analysis Example Construction Analysis Suspension Bridge Wizard generates a 3-dimensional suspension bridge including self-anchored. Initial geometry is found, and unstrained lengths and initial cable forces are calculated.

Geometry Section & Material B Deck System Preview A C D
Suspension Bridge Wizard Geometry Section & Material Deck System Preview A B Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis C Input node coordinates & hanger distances D

Geometry Section & Material B Deck System Preview A C D
Suspension Bridge Wizard Geometry Section & Material Deck System Preview B Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis A C Define sections and materials of each part of the bridge. D

Sectional Property Calculator(SPC)
Suspension Bridge Wizard Deck Cross Section defined by SPC (Sectional Property Calculator) Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis Sectional Property Calculator(SPC)

Geometry Section & Material B Deck System Preview A C D
Suspension Bridge Wizard Geometry Section & Material Deck System Preview A B Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis C Input width, height and weight of deck. D

Geometry Section & Material B Deck System Preview A C D
Suspension Bridge Wizard Geometry Section & Material Deck System Preview B Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis A C Model preview is updated in real time as the geometry data is input. D

Suspension Bridge Wizard
Find cable coordinates and forces using the equilibrium condition and nonlinear analysis of cable Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis Equilibrium in X-Z Plane Equilibrium in Y-Z Plane Generate the model with simplified deck and pylons.

The actual design model
Suspension Bridge Analysis Control The model from the Wizard has been simplified based on the assumptions in the wizard. Therefore, the model has to be modified according to the actual design. After updating, the 2nd analysis has to be performed to reflect the change of the system. Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis The simplified model from the wizard The actual design model

Suspension Bridge Analysis Control Dialog
Wizard Analysis Control Analysis Example Construction Analysis Select the node group, which is to be updated, and the sag points. Suspension Bridge Analysis Control Dialog

Suspension Bridge Analysis Control Dialog
Wizard Analysis Control Analysis Example Construction Analysis Select the node group which is to be updated and in the sag point. Select the load case for which the cable forces will satisfy the equilibrium condition. Suspension Bridge Analysis Control Dialog

Suspension Bridge Analysis Control
Structural Data and Convergence Criteria Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis Perform Geometric Nonlinear Analysis Calculate inequilibrium forces Calculate node coordinates and element forces In case of a self-anchored suspension bridge, deformations occur at the tops of the pylons and the ends of the deck due to the axial forces in the deck. The longitudinal deformation means the change in the boundary condition, and this change is reflected by introducing the initial element forces. Check Convergence with displacement difference Update node coordinates Re-calculation of the unstrained lengths Calculate the element equilibrium forces Determine the node coordinates Determine the unstrained lengths Determine the element equilibrium forces Suspension Bridge Analysis Control Dialog

3-Dimensional Self-Anchored
Analysis Examples Example of Suspension Bridges Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis Youngjong Bridge 3-Dimensional Self-Anchored

Example of Suspension Bridges
Analysis Examples Example of Suspension Bridges Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis Kwangan Bridge

Example of Suspension Bridges
Analysis Examples Example of Suspension Bridges Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis No Hangers in the Side Spans

Example of Suspension Bridges
Analysis Examples Example of Suspension Bridges Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis Inclined Hangers

Backward Geometric Nonlinear Analysis
Perform backward nonlinear analysis considering the element forces at the initial state as the element equilibrium forces. Suspension Bridge Wizard Analysis Control Analysis Example Construction Analysis

Initial Equilibrium State Analysis
Cable Pretensions in Construction Stages Forward Analysis using Initial State Pretensions The Calculation of the Closing Forces Analysis Example Find the initial cable pretensions using ‘Unknown Load Factor’ Obtain optimized cable pretensions satisfying the constraints. In case the numbers of constraints and unknowns are the same, pretensions can be found by simultaneous equations, which are quick and simple. Unknown Load Factor

Set up constraints and unknowns
Cable Pretensions in Construction Stages Iteration Initial Equilibrium State Analysis Cable Pretensions in Construction Stages Forward Analysis using Initial State Pretensions The Calculation of the Closing Forces Analysis Example Set up constraints and unknowns Load Factors Found Cable pretensions in construction stages can be also obtained by Unknown Load Factor. Iterative analysis method enables us to find cable forces of the bridges in which time dependent effects are considered. Iteration Control

Pretensions in the Initial State
Forward Analysis using Initial State Pretensions Using pretensions from the initial state analysis, cable pretensions in the construction stages (CS) can be found without the backward analysis. Initial Equilibrium State Analysis Cable Pretensions in Construction Stages Forward Analysis using Initial State Pretensions The Calculation of the Closing Forces Analysis Example Pretensions in the Initial State

Construction Analysis Control
Forward Analysis using Initial State Pretensions The additional pretensions are required in CS because of the difference in cable lengths between the initial state and the construction stages. Such additional force is called the ‘Lack of Fit Force’. Initial Equilibrium State Analysis Cable Pretensions in Construction Stages Forward Analysis using Initial State Pretensions The Calculation of the Closing Forces Analysis Example Construction Analysis Control Cable Length in initial State Cable Pretension in Initial State Cable Pretension in CS State Cable Length in Construction Stages Lack of Fit Force

The Calculation of the Closing Forces
The closing force calculation is required in order to keep the key-segment become continuous with decks at the joints. The closing force is calculated by applying the lack of fit force to the beam element (key segment). Initial Equilibrium State Analysis Cable Pretensions in Construction Stages Forward Analysis using Initial State Pretensions The Calculation of the Closing Forces Analysis Example Without closing force The specified displacement is calculated so that the key segment can be continuous with the neighboring elements. The displacement is transformed into element forces and applied to the key segment With closing force

Forward Analysis Using the Lack of Fit Force
Using the ‘Lack of Fit Force’, the final result of the forward analysis can be obtained as the same as the result of the initial state. Initial Equilibrium State Analysis Cable Pretensions in Construction Stages Forward Analysis using Initial State Pretensions The Calculation of the Closing Forces Analysis Example Initial State The pretension forces from the initial state are applied to the construction stage model as well. Construction Stage

Analysis Example Stonecutters Bridge Example of a Cable Stayed Bridge
Initial Equilibrium State Analysis Cable Pretensions in Construction Stages Forward Analysis using Initial State Pretensions The Calculation of the Closing Forces Analysis Example Stonecutters Bridge