Performance of self-consolidating concrete used to repair parapet wall in Montreal

Title: Performance of self-consolidating concrete used to repair parapet wall in Montreal
Author(s): K.H. Khayat, R. Morin
Paper category : conference
Book title: International RILEM Symposium on Self-Compacting Concrete
Editor(s): O. Wallevik and I. Nielsson
Print-ISBN: 2-912143-42-X
e-ISBN: 2912143713
Publisher: RILEM Publications SARL
Publication year: 2003
Pages: 913 - 919
Total Pages: 7
Nb references: 1
Language: English

Abstract: Self-consolidating concrete (SCC) can be used to facilitate the casting of densely reinforced sections that are difficult to consolidate. Such concrete can accelerate the placement rate of concrete and secure superior surface quality. Typically, superplasticized concrete is employed in the casting of densely reinforced sections, and depending on the access to consolidation, segregation and surface defects can often be visible at the surface necessitating some patching of defective areas. The repair of the upper surface of a 200-m long retaining wall located in a patrimonial area in Montreal was required given extensive corrosion damage and delamination of the concrete. The wall, located along a heavily travelled boulevard leading to downtown Montreal, was built in 1959 adjacent to prestigious properties. In some cases, the wall measured 4 m in height and did not show signs of damage on the front side facing the private properties. In order to minimize any inconvenience to the neighbourhood, it was decided to demolish the back portion of the wall facing the traffic. The repair consisted of removing 150 mm of existing concrete and replacing the outer reinforcement with reinforcing bars in both directions anchored to the existing substrate. Considering the complex new form of the parapet wall that incorporated special surface definitions required by the architect and return angles (Fig. 1), and given the restricted access to the bottom of the bell-shaped section to ensure proper consolidation, the City of Montreal's engineers selected SCC to ensure high quality architectural finish.The wall was built in 50 sections separated by expansion joints. In total, 100 m3 of SCC was required for the repair. The contractor, who was using such concrete for the first time was impressed by the simplicity of its utilization having to use internal vibrators at bare occasions when the delay between two concrete deliveries exceeded 5 minutes. This procedure ensured that no cold joints were visible at the surface.

Online publication: 2003-08-21
Publication type : abstract_only
Public price (Euros): 0.00