Optimization Of Cable Pre-tension Forces In Multi-tower Cable-stayed Bridges With Crossing Cables Considering The Dead Load Allocation

Abstract

Bridges Are A Vital Element Of Transportation Networks. As Any Disorder In The Maintenance Or Utilization Of Bridges May Cause Irrecoverable Incidents, The Vulnerability Of Bridges To Earthquakes Must Be Seriously Considered. Considering The Unjustified Use Of Force Displacement Design Methods In The Seismic Design Of Important Structures, Such As Bridges, The Use Of An Energy-based Approach With Nonlinearly Behaving Materials And The Concept Of Hysteretic Energy Are More Rational And Practical. The Cable Stayed Bridge Is One Of The Modern Bridges Which Were Built For The Longer Spans And For Better Enhancement Of The Work In The Field Of Aesthetic Appearance And Durability, Therefore There Is A Need Of Study Which Overcomes The Idea About The Different Possibilities In The Structural Arrangement In The Terms Of Economy And Aesthetical Appearance. This Study Reveals An Idea About The Behaviour Of Cable Stayed Bridges With Prestressed Cables And Cross Section Arrangements Under The Moving Loads. The Modelling And Analysis Of Bridge Has Been Carried Out Using Csi Bridge With Vehicular Interaction As Per IRC & AASHTO Methods & The Effects Of Moving Loads On The Bridge Has Been Studied. With The Moving Load Configuration, The Bridge Has Also Been Analysed For The Seismic Load As Per Indian Standard For Zone III Using Elastic Response Spectrum Approach. For The Modelling Of Bridges, The Arrangement Of Self-anchored Cable Stays Has Been Considered As Semi Fan Type With The Constant Dimensions Of Height Of Pylon And Span Of Bridge. From These Results, The Behaviour Of The Cable Stayed Bridge Has Been Easily Determined In The Assumed Appropriate Conditions. A Static Moving Load Along With Seismic Analysis Is Carried Out And Various Response Quantities Like Bending Moment, Shear Force, Displacement, And Axial Force Are Represented. An Effort Was Made To Evaluated The Displacements Of The Cable Stayed Bridge Deck And Pylon Under The Action Of Traffic Loads & Seismic Loads Which Are Helpful In Limiting The Limitations Of Different Shapes Of Pylon Too. From The Results It Has Been Observed That The Diamond Shaped Pylons Shows Better Performance For Both IRC & AASHTO Loading And Gives Satisfactory Results And The Values Of Displacement, Forces And Moments For AASHTO Loading Is Lesser Than The IRC Loading.

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