Fatigue Testing of Cables – Issues and Lessons Learned

Mapping Intimacies ◽

10.24904/footbridge2022.014 ◽

2021 ◽

Author(s):

Jeremy Lahaye ◽

Dan Fitzwilliam

Keyword(s):

Fatigue Testing ◽

Suspension Bridge ◽

Lessons Learned ◽

Bridge Design ◽

Cable System ◽

Pedestrian Bridge ◽

Main Cable ◽

Pedestrian Bridges ◽

Cable Systems ◽

Scioto River

Pedestrian bridge design is becoming more demanding and challenging as architects create new ways to experience bridges. This is particularly evident in the design of cable supported pedestrian structures.Innovative and creative concepts require a higher level of fatigue testing to verify cable systems meet design demands and reach service design life.The Scioto River Pedestrian Bridge is one such example of innovative pedestrian bridge design. The structure is a suspension bridge with a non-redundant main cable system. Cable supported pedestrian bridges have demonstrated a proclivity for fatigue issues in the past. To address this concern, refined fatigue testing requirements were developed which were intended to verify that the cable system and manufacturing quality control were fit for the unique structure demands. The lessons learned through the process of design, testing, and construction of the cables on this project are useful tools for teams seeking to successfully deliver future cable supported bridge projects.

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Walk Through the Eye of a Needle

10.24904/footbridge2022.010 ◽

2022 ◽

Author(s):

Dan Fitzwilliam

Keyword(s):

Design Process ◽

Suspension Bridge ◽

Lessons Learned ◽

Full Measure ◽

Bridge Design ◽

Pedestrian Bridge ◽

Current Design ◽

Design Software ◽

Design And Testing

Pedestrian bridge design is becoming more demanding and challenging as architects and engineers utilize the full measure of design ability available with current design software. This presentation will review the design process for the more unique aspects of this suspension bridge. The presentation will conclude with lessons learned during the design process. Observations from the design of this bridge will form the basis of recommendations for the enhanced design and testing specifications for cable supported bridges.

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Analysis on Construction Control about Main Cable System of Cableway Bridge

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.711.361 ◽

2014 ◽

Vol 711 ◽

pp. 361-365

Author(s):

Guo Jun Yang ◽

Xian Wu Hao ◽

Ji Peng Yang

Keyword(s):

Suspension Bridge ◽

Form Finding ◽

Cable System ◽

Method Of Calculation ◽

Main Cable ◽

Practical Engineering ◽

Cable Force ◽

Design Value ◽

The Relationship ◽

Good Agreement

Cableway bridge is a type of suspension bridge which mainly depends on the cable to suffer the force. The method of calculation unstressed length by parabolic method is introduced in this paper, and the form finding analysis of main cable is also analyzed, thus the method of calculation vector height of middle cross and cable force is concluded. Finally, the relationship between vector height and cable force is fitted based on the practical engineering, bedsides, the error is analyzed between design value and measured value, which comes to the conclusion that measured value is good agreement with design value.

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An Improved Analytical Algorithm on Main Cable System of Suspension Bridge

Applied Sciences ◽

10.3390/app8081358 ◽

2018 ◽

Vol 8 (8) ◽

pp. 1358 ◽

Cited By ~ 5

Author(s):

Chuanxi Li ◽

Jun He ◽

Zhe Zhang ◽

Yang Liu ◽

Hongjun Ke ◽

...

Keyword(s):

Search Algorithm ◽

Suspension Bridge ◽

Internal Force ◽

Element Formulation ◽

Cable System ◽

Tangent Stiffness Matrix ◽

Main Cable ◽

Penalty Factor ◽

Analytical Algorithm ◽

Internal Force Vector

This paper develops an improved analytical algorithm on the main cable system of suspension bridge. A catenary cable element is presented for the nonlinear analysis on main cable system that is subjected to static loadings. The tangent stiffness matrix and internal force vector of the element are derived explicitly based on the exact analytical expressions of elastic catenary. Self-weight of the cables can be directly considered without any approximations. The effect of pre-tension of cable is also included in the element formulation. A search algorithm with the penalty factor is introduced to identify the initial components for convergence with high precision and fast speed. Numerical examples are presented and discussed to illustrate the accuracy and efficiency of the proposed analytical algorithm.

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Partially Strengthened Main Cable System for the Rehabilitation of an Old Suspension Bridge

IABSE Congress, Stockholm 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment ◽

10.2749/stockholm.2016.1525 ◽

2016 ◽

Author(s):

Bobe Lee ◽

Minjae Lee ◽

Taekwun Park

Keyword(s):

Aging Effect ◽

Suspension Bridge ◽

New Method ◽

Suspension Bridges ◽

Cable System ◽

Main Cable ◽

Bridge Rehabilitation ◽

The World ◽

Extent Of Damage

Bridge rehabilitation projects for enhancing the safety and serviceability of old bridges are carried out widely around the world. Especially, suspension bridges are intensively maintained with high construction budgets. The damaged hanger rope, stiffening girder and main tower in suspension bridges can be repaired, strengthened or replaced. However, in the case of a main cable, the remedy until now only removes rust and applies surface repainting. Basically, the main cable consists of thousands of small wires, which is not replaceable. A damaged or disconnected wire also cannot be repaired or replaced. This paper suggests a new method for strengthening a main cable that is deteriorated by the aging effect. By small cables connecting a couple of cable bands on both sides from a pylon, the strength of the main cable can be increased and the possibility of slip of the cable bands are decreased. This suggestion is introduced by an example of an old suspension bridge that has been opened to traffic for forty years. The reinforcing level of the main cable should be decided by the extent of damage. Hence, the level of strengthening of the main cable can be easily controlled by only the amount of ancillary cables.

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Optimal Maintenance of Suspension Bridge Cable Systems

IABSE Conference, Copenhagen 2018: Engineering the Past, to Meet the Needs of the Future ◽

10.2749/copenhagen.2018.227 ◽

2018 ◽

Author(s):

J. Fredrik Melén

Keyword(s):

Suspension Bridge ◽

Suspension Bridges ◽

Maintenance Strategy ◽

Cable System ◽

Safety Level ◽

Optimal Maintenance ◽

Cable Systems ◽

Bridge Cable ◽

Main Cables ◽

Do So

Suspension bridges are iconic, large, complex and unique structures with great public value. The main cables on suspension bridges are difficult to inspect and maintain and are virtually irreplaceable, although this has been done in two cases at extreme cost. Maintaining the main cables in an optimal manner is therefore of utmost importance. When developing an optimal maintenance strategy for the main cables, other related elements should be considered and included in the strategy, hence the entire cable system is the topic for this paper. Maintenance of the cable system is relatively expensive, but the costs can be minimized if an optimal maintenance strategy is developed and followed. The main goal of the maintenance strategy is to keep the bridge open at full traffic capacity at all times with the proper safety level and to do so at the lowest cost possible.

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