New Frontiers in Multi-span Prestressed Concrete Deck Construction: A Case Study

Abstract

Until 2016, the in situ, span-by-span, prestressed concrete deck construction of multi-span bridges was limited to spans up to 78 m. This construction method, in some cases, ensures verifiable advantages in terms of construction simplicity and reduction in material consumption. After scientific and technical validation of the organic prestressing technology application in movable scaffolding systems in 2005, and evaluation of its potential features, a long-term multidisciplinary research and development project was developed to evaluate the possibility of using this technology for in situ construction of multi-span decks with spans up to 90 m. In 2018, in Turkey, the first viaduct using this technology anywhere in the world was completed. In the present paper, following a presentation of prior scientific and technological achievements, the main technical data of this case study are given, highlighting its results. This technological achievement is a contribution to the state of the art of bridge engineering and to sustainability.

Design Basis of Movable Scaffolding Systems Following American and European Code Provisions and Recommendations

“…The main application of MSSs is related to the construction of bridges, the span lengths of which have mainly ranged between 25 m and 70 m (Members of IABSE WG 6, 2018) with an exception of the Ahrtal Bridge in Germany built with a span of 108 m (Majewski, 1976). Nevertheless, the OPS enabled MSSs to reach span lengths up to 90 m (Pacheco et al, 2020). Many reasons make MSSs the preferable option in building a multi-span bridge.…”

“…Many reasons make MSSs the preferable option in building a multi-span bridge. According to different authors (Däbritz, 2011;Díaz de Terán et al, 2016;Pacheco et al, 2020;Rosignoli, 2013), MSSs are a suitable construction method for several reasons mentioned below.…”

“…Regarding the location or special demands, application of MSSs is advisable when there are high architectural requirements and difficult topography. Nonetheless, MSSs also have certain disadvantages and limitations (Pacheco et al, 2020;Rosignoli, 2013), such as the cost of shipping, assembly, and dismantling, high level of technology required, possible weight of the MSS that can have an impact on the design of the bridge, the speed of construction compared to other techniques, and the limited span length. In addition, MSSs can be also used for other applications, such as the overhaul and demolition of bridges (Däbritz & Mertinaschk, 2018).…”

“…The launching girders are normally box girders or truss girders made of steel (Members of IABSE WG 6, 2018). Nevertheless, in some cases, to reach longer spans, these girders can present a bowstring configuration (Pacheco et al, 2020). In both situations, the structure can include the OPS as part of the structure acting during the stationary stage.…”

“…At the beginning of the twenty-first century, a new generation of MSSs has appeared, which implies application of the organic prestressing system (OPS) (Pacheco, 2008;Pacheco et al, 2007). In the most recent developments, MSS technology has proved suitable and efficient for in-situ span-by-span deck erection of multi-span viaducts, offering such benefits as safe construction, simple geometric control, reduced material consumption, and a beneficial impact on sustainability (Pacheco et al, 2020).…”