Abstract: On most short span bridges, headstocks are used to connect the bridge superstructure with the substructure. Deterioration of existing headstocks due to increased traffic loading and structural aging has become evident in many bridges in Australia and worldwide. The number of heavy trucks and traffic volume on these bridges have increased and exceeded the values used at the time of their design. Structural upgrades of headstocks usually require the existing headstock to be strengthened, both in shear and flexure, and the magnitude of increase is normally in the order of 100% of the original capacity. As such, there is an urgent need for strengthening bridge elements such as headstocks using appropriate strengthening technologies. External post tensioning is a suitable method for repairing bridge structures in strength and serviceability. This repair method gives engineers a viable and economical alternative to replacing bridge structures. The downside of external post tensioning work to date is the use of mainly steel tendons in the post tensioning components. These components are inherently vulnerable to corrosion under the conditions in which these structures exist. A viable alternative needs to be found. Fibre Reinforced Plastic (FRP) materials have been used as an alternative materials for external post-tensioning to overcome the problems related with corrosion of steel. One of the major issues when using FRP tendons for post-tensioning purposes is the design of anchorages. As such, there is need to find to develop suitable anchoring techniques. A prestressed fibre wrap system has been proposed for strengthening of headstocks, which forms an innovative solution to overcome the above mentioned problems. The applicability of the proposed system has been experimentally verified using model tests. This paper describes this new technology, which is ideally suited for strengthening of headstocks. It also discusses the effect of existing shear cracks on strengthening and the importance of repairing such cracks to increase capacity of the member by external post-tensioning.
To cite this article: Aravinthan, T and Heldt, T. Innovative Strengthening Technique Using Prestressed Fibre Wraps for Bridge Headstocks [online]. In: Stewart, Mark G (Editor); Dockrill, Brad (Editor). Australian Structural Engineering Conference 2005. Sydney, N.S.W.: Engineers Australia, 2005: -.
[cited 31 Jul 16].
Aravinthan, T; Heldt, T;
Source: In: Stewart, Mark G (Editor); Dockrill, Brad (Editor). Australian Structural Engineering Conference 2005. Sydney, N.S.W.: Engineers Australia, 2005: -.
Document Type: Conference Paper, Research
Traffic engineering; Bridges--Live loads; Bridges--Maintenance and repair; Steel, Structural--Corrosion; Bridges;
(1) University of Southern Queensland, Toowoomba, QLD, Australia
(2) University of Southern Queensland, Toowoomba, QLD, Australia
Database: Engineering Collection