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It is a common request for Movable Scaffolding Systems (MSS) to be designed to withstand wind loads, despite the site location. In contrast, seismic events aren’t frequently considered while designing an MSS. Unlike wind loading, seismic events are very rare and with characteristics difficult to predict – therefore, the concept of operational limits or emergency safety devices is not applicable. In case of bridges located in hazardous seismic zones, seismic events should be taken into account while designing the MSS. The most critical phase is the concrete pouring stage, in which the mass is maximum. In this stage, vibration frequencies are largely dependent from the MSS type (overhead or underslung) and the MSS support configuration. This paper is focused on MSS design to withstand seismic events. Considerations on load evaluation, combination criteria and design options are given, based on a practical case.

This paper aims to describe the SMART-OPS research project, present preliminary results of the experimental campaign and foresee the characteristics and advantages of the product under development. In the first stage, a commercial monitoring equipment was adopted. The paper will describe preliminary results obtained with this equipment to demonstrate in a full-scale MSS under normal operation the advantages and challenges of monitoring. In the second stage, a customized monitoring system is under development.The monitoring system was implemented in a Movable Scaffolding System (MSS) used to build spans up to 70m of prestressed concrete deck. The monitoring scheme included 2 sonic anemometers, 29 strain gages and 3 triaxial accelerometers. The MSS built 12 spans near Bratislava between May 2019 and February 2020.

Modern bridge construction equipment are actual living structures, in which human activity plays an important role in equipment safety and structural performance.Demand for high productivity pushes the development of increasingly audacious structural concepts, leading to integration of high capacity hydraulic components as pure structural elements.The use of large movable structures (LMS) such as launching gantries (LG) or movable scaffolding systems (MSS) is widespread in Europe and North America and specialized crews have been trained throughout the years. Increasing implementation of modern bridge construction processes in developing regions not yet familiarized with inherent construction equipment brings new challenges in terms of safety.Safety is the ultimate result of combined and coordinated activity of contractors, bridge designers, construction process developers, manufacturing quality controllers and equipment operators.This paper aims to provide a general overview on safety and risk management in bridge construction processes. A multidisciplinary design approach, strongly governed by an effective risk analysis is herein explored, making references to practical examples. Experimental testing may and must be used as complementary design tool. The role of structural monitoring and active control systems is also considered, highlighting the practical example of Organic Prestressing System (OPS), an actively controlled prestressing system that increases structural efficiency.Main conclusions drawn in the end may be generalized to other design and construction activities

Structural safety may be seen as an outcome of 3 major factors: Design, Construction/Erection and Materials. Each of these factors is usually governed by specific standards. In order to reach a satisfactory outcome, the standards should ideally be coherent and complementary. In the regions that led the development of structural engineering (US, Europe, Japan) it took decades to develop articulated standards and this development is still ongoing – for instance, improvement of materials and quality control promote material reduction, safety factors or even incorporation of new materials into design standards.As globalization continues to accelerate, structural engineering companies simultaneously face global competition and new global opportunities. Challenges arise in situations in which Design, Construction and Materials’ standards are not governed by a common language or background. The use of large bridge construction equipment such as LG or MSS is widespread in Europe and North America. Increasing implementation of modern bridge construction processes in developing regions not yet familiarized with inherent construction equipment bring new challenges in terms of safety and standard harmonization. Some of these challenges are addressed in this paper. Main conclusions drawn in the end may be generalized to other design and construction activities.

This paper describes the background of the long-term R&D project which brought out the first application of a Large Movable Scaffolding System (LMSS) for the construction of a multi-span viaduct with successive spans ranging up to 90m long in Ankara region, Turkey. This is the first LMSS for multi-spans above 78 m spans ever applied worldwide. After mentioning the historical background and precedent state of art, this paper presents the main identified technical challenges and how they were overcome. The first application is briefly described, allowing defining its impact on present state of art. Finally, conclusions are drawn where it is verified that there are now more possibilities to erect multi-span viaducts, including with span-by-span in situ construction, which represent very significant reduction on materials consumption when compared with other construction methods.