Se describen reparaciones de subestructuras de puentes efectuadas empleando hormigón autoconsolidable (self-consolidating concrete, SCC). El Departamento de Transporte de Virginia (Virginia Department of Transportation, VDOT) ha utilizado con éxito SCC en proyectos de reparación de puentes durante unos cinco años. Los requisites de colocación y pruebas para SCC son similares a los del hormigón conven-cional, el encofrado requerido proporciona protección inicial contra la pérdida de humedad, y el acabado puede ser tan liso comò la superficie del encofrado. Las reparaciones completa-das muestran que se puede colocar SCC con éxito y el producto terminado tiene mínimas grietas.%VDOT has been successfully using SCC on bridge substructure repair projects for about 5 years. Our experience shows that: 1. Retarding admixtures and workability-retaining admixtures can be included in SCC mixtures to maintain workability for the duration of a placement; 2. Proper selection and proportioning of ingredients, including VMAs, ensures that the SCC mixture does not segregate and maintains stability; 3. Following proper placement procedures and using pumps and other means that provide a head and constant delivery of concrete is crucial for the concrete to be able to consolidate with no external vibration (placement using handheld buckets should be avoided); and 4. Formwork must be designed to handle the pressure of SCC, and it may be necessary to slow the placement rate and limit the height of placement to prevent bulging or failure.
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