Microstructural and mechanical characterisation of the Simon Bolivar's iron bridge structure, 19th century, Arequipa, Peru

Abstract

The microstructure of the main structural elements (Phoenix columns, transversal beams and tie-rods) of the Simón Bolivar iron bridge, located in Arequipa (Peru), was investigated. The bridge was supposedly designed by Gustave Eiffel and opened to the public in 1882. The characterisation revealed that the columns, beams and tie-rods are made of puddled iron (ferritic matrix of equiaxial grains and numerous slag inclusions). The tensile properties were estimated by hardness and nanohardness measurements, and the tensile strength varied between 285 and 390 MPa and the Young's modulus from 187 to 198 GPa. The components of puddled iron with the same provenance, Phoenix Iron Company, showed typical variations in the chemical composition and microstructure of the slag inclusions. The microanalysis results of the slag inclusions indicated that the wüstite phase presented qualitatively the same composition with pronounced variations in the ratio between V 2 O 5 and TiO 2 contents, confirming that a single parameter cannot be used to determine the provenance of iron artefacts. The intense presence of slag inclusions in the puddled iron components (~ 10% in volume fraction) heterogeneously distributed in the iron illustrates the technological limits of the iron refining technique of the time.

Preserving Heritage Riverine Bridges: A Hydrological Approach to the Case Study of the Grau Bridge in Peru

“…The Grau Bridge, along with other structures spanning the Chili River, exhibits signs of insufficient maintenance, thereby jeopardizing the safety of users [11]. Consequently, a thorough investigation into its vulnerability is imperative to mitigate associated risks, enabling necessary interventions to extend its operational lifespan while preserving its heritage significance [12,13]. Among the various risks, flood risk is particularly critical and depends, in part, on the positioning of infrastructure such as houses along the banks of natural channels.…”

Preserving Heritage Riverine Bridges: A Hydrological Approach to the Case Study of the Grau Bridge in Peru

“…The Grau Bridge, along with other structures spanning the Chili River, exhibits signs of insufficient maintenance, thereby jeopardizing the safety of users [12]. Consequently, a thorough investigation into its vulnerability is imperative to mitigate associated risks, enabling necessary interventions to extend its operational lifespan while preserving its heritage significance [13,14]. Among the various risks, the flood risk is particularly critical and depends, in part, on the positioning of infrastructure such as houses along the banks of natural channels.…”