Digitally fabricated weak interfaces to reduce minimum reinforcement in concrete structures

[EN] Crack initiators in reinforced concrete structures can facilitate fulfilling the serviceability requirements. They can be used as a design parameter to diminish the minimum reinforcement for members subject to imposed deformation and exposed to the environment as they reduce the crack spacing a...

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Detalles Bibliográficos
Autores: Bichof, Patrick, Ammann, Rebecca, Näsbom, Andreas, Kaufmann, Walter, Mata Falcon, Jaime|||0000-0001-8701-4410
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/212306
Acceso en línea:https://riunet.upv.es/handle/10251/212306
Access Level:acceso abierto
Palabra clave:Concrete structures
Crack initiators
Digital fabrication
Material efficiency
Minimum reinforcement
Weak interfaces
MECANICA DE LOS MEDIOS CONTINUOS Y TEORIA DE ESTRUCTURAS
Descripción
Sumario:[EN] Crack initiators in reinforced concrete structures can facilitate fulfilling the serviceability requirements. They can be used as a design parameter to diminish the minimum reinforcement for members subject to imposed deformation and exposed to the environment as they reduce the crack spacing and width when arranged close enough. While crack initiators in conventional concrete construction are cumbersome to provide (e.g., by construction joints or taperings), they are inherent to layered extrusion processes with digital fabrication technologies: the tensile strength is typically reduced locally in interfaces between layers. Rather than trying to avoid these weak interfaces, this paper discusses the potential of taking advantage of them to act as crack initiators reducing the minimum reinforcement content. A tension chord-based model is developed to (i) account for the local strength reduction and (ii) predict the effect of weak interfaces on the expected crack spacing and width. As a key finding, the model predicts a reduction of the required minimum reinforcement ratio proportional to the locally decreased concrete tensile strength for a specified maximum crack width requirement under imposed deformations. An experimental campaign on five layered and three reference tension ties confirmed the clearly positive impact of weak interfaces on crack spacings and widths.