A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Composite materials contribution in strengthening concrete structures affected by alkali-aggregate reaction
AAR (alkali-aggregate reactivity) is a chemical reaction that occurs in some concrete structures. AAR is a reaction between pore solution alkali hydroxide and some siliceous aggregates. The damage to the concrete induced by AAR is very important with expansion and cracking. The main purpose of this investigation is to evaluate the effectiveness of the use of external bonded FRP (fibre reinforced polymer) on the durability of civil engineering structures damaged by alkali reaction (mechanical behaviour determination, comparison with Larive's method and confinement efficiency). In a first approach, we are working on a mortar specimen containing alkali-silica aggregates. The deterioration of mortar is determined from the expansion measures and from the measure of mechanical properties. To reduce the necessary duration of development of alkali-aggregate reaction, two accelerated mortar bar tests are evaluated: immersion in saturated NaCl solution at 50 deg C; immersion at 38 deg C (P 18 585 AFNOR standard). Two types of sample are made: no reactive mortar and reactive mortar with opal sand and siliceous limestone (Tournai sand). Composite skins (FRP reinforcement) are placed at the beginning or after some expansions. The linear expansion of mortar bars exposed to several temperatures (and pressure) in various storage conditions for different testing periods (5 h, 28 days or 3 months) is measured. The mechanical behaviour is also determined on confined and unconfined specimens.
Composite materials contribution in strengthening concrete structures affected by alkali-aggregate reaction
AAR (alkali-aggregate reactivity) is a chemical reaction that occurs in some concrete structures. AAR is a reaction between pore solution alkali hydroxide and some siliceous aggregates. The damage to the concrete induced by AAR is very important with expansion and cracking. The main purpose of this investigation is to evaluate the effectiveness of the use of external bonded FRP (fibre reinforced polymer) on the durability of civil engineering structures damaged by alkali reaction (mechanical behaviour determination, comparison with Larive's method and confinement efficiency). In a first approach, we are working on a mortar specimen containing alkali-silica aggregates. The deterioration of mortar is determined from the expansion measures and from the measure of mechanical properties. To reduce the necessary duration of development of alkali-aggregate reaction, two accelerated mortar bar tests are evaluated: immersion in saturated NaCl solution at 50 deg C; immersion at 38 deg C (P 18 585 AFNOR standard). Two types of sample are made: no reactive mortar and reactive mortar with opal sand and siliceous limestone (Tournai sand). Composite skins (FRP reinforcement) are placed at the beginning or after some expansions. The linear expansion of mortar bars exposed to several temperatures (and pressure) in various storage conditions for different testing periods (5 h, 28 days or 3 months) is measured. The mechanical behaviour is also determined on confined and unconfined specimens.
Composite materials contribution in strengthening concrete structures affected by alkali-aggregate reaction
Beitrag von Verbundwerkstoffen zur Verfestigung von Betonstrukturen, die durch die Alkali-Aggregat-Reaktion beeinflußt sind
Curtil, L. (author) / Ferrier, E. (author) / Ronel-Idrissi, S. (author) / Hamelin, P. (author)
2003
15 Seiten, 13 Bilder, 6 Tabellen, 8 Quellen
Article (Journal)
English
Betonmörtel , chemische Reaktion , Flüssigkeit , Pore , Rissbildung , Reaktivität (Reaktionsfähigkeit) , mechanische Stabilität , faserverstärkter Kunststoff , Prüfverfahren , Eintauchen , Salzlösung , Temperatureinfluss , Zeitdauer , Quellung , Druckfestigkeit , Ausdehnungskoeffizient , mechanisches Modell , Armierung , Beton
| British Library Online Contents | 2003
| British Library Conference Proceedings | 2001
Concrete modelling for expertise of structures affected by alkali aggregate reaction
| British Library Online Contents | 2010
Concrete modelling for expertise of structures affected by alkali aggregate reaction
| Online Contents | 2010