Geomechanik und Tunnelbau最新文献

The construction of Venezia station of Rome Line C Underground presents a significant engineering challenge within an archaeological and monumental context. The civil works will begin with the excavation of an 85 m long diaphragm wall, after which the archaeological investigation will be carried out to a depth of 15 m, before the construction of the cross walls to reduce the deformability effects. The complex geological conditions necessitated for the ground freezing technology for the tunnel excavation. Geotechnical and structural analyses have been conducted to study the potential effects of the excavation on the monuments leading to the design geotechnical and structural interventions for their protection. At the end of the excavation, some of the archaeological structures discovered will be relocated to the atrium of the station that will represent a unique ensemble with the museums of Venezia Palace, the Vittoriano, and the Roman Forum.

The Brenner Base Tunnel is considered one of the most significant infrastructure projects of the century, driven by continuous development and innovative solutions. These improvements span all phases of the project, from planning to operation, allowing for new, contemporary requirements to be addressed even during construction. Special attention is given to innovative technologies that enhance the tunnel's efficiency, safety, longevity, and maintainability. This article discusses various innovations, such as advanced materials, modern monitoring systems, and techniques that enable safe tunnelling even under challenging geological conditions. The Brenner Base Tunnel is thus not only a technical marvel but also a model for future infrastructure projects that must be designed for long-term sustainability.

Der Brenner Basistunnel gilt als eines der bedeutendsten Infrastrukturprojekte des Jahrhunderts und wird durch kontinuierliche Weiterentwicklungen und innovative Lösungen geprägt. Diese Verbesserungen betreffen alle Phasen des Projekts, von der Planung bis hin zum Betrieb, und ermöglichen es, auch während des laufenden Baus auf neue, zeitgemäße Anforderungen zu reagieren. Besondere Aufmerksamkeit wird dabei auf innovative Technologien gelegt, die die Effizienz und Sicherheit des Tunnels erhöhen sowie dessen Langlebigkeit und Wartungsfreundlichkeit gewährleisten. Der Artikel geht detailliert auf verschiedene Neuerungen ein, wie etwa fortschrittliche Materialien, moderne Überwachungssysteme und Verfahren, die ein sicheres Vorantreiben des Tunnels auch unter schwierigen geologischen Bedingungen ermöglichen. Der Brenner Basistunnel stellt somit nicht nur ein technisches Meisterwerk dar, sondern auch ein Vorbild für zukünftige Infrastrukturprojekte, die langfristig und nachhaltig ausgelegt sein müssen.

Tunnel excavation projects in urban environments pose significant challenges due to their potential impact on existing structures, infrastructure, and historical buildings. In Florence, Italy, a high-speed railway underpass is being constructed as part of the Scandinavian Mediterranean Corridor, using earth pressure balance tunnel boring machines. This study highlights the importance of continuous monitoring and adaptive strategies to manage unforeseen soil conditions during urban tunnel excavation, through a focus on induced settlements along Viale Lavagnini and the predictive analysis on the Renaissance-style Fortezza da Basso. Settlement monitoring in the urban area assessed interactions between tunnelling activities and surrounding infrastructure and showed localized variations due to hydraulic perturbations and soil consolidation, while settlements generally remained within design limits. A 3D numerical model was developed for the Cavaniglia bastion at Fortezza da Basso to evaluate the impact of tunnel-induced strains. Results showed the strains were within acceptable thresholds.

In the realm of modern infrastructure development, tunnels play a key role, serving as vital channels for transportation, utilities, and various other applications. Ensuring the successful construction and operation of tunnels is dominant in maintaining the efficiency and safety of these essential passageways. However, challenges arise when tunnels intersect with the intricate geological characteristics of the surrounding rock mass, particularly in tectonic regions. The stability and performance of tunnels can be significantly affected by various factors, necessitating a thorough understanding of their behavior when excavated within complex geological structures, such as those at the Alps–Apennines contact zone. In these areas, the energy accumulated from tectonic-induced stresses can play a crucial role in tunnel design and construction, influencing stability conditions and determining the most appropriate excavation and support strategies. The article examines the construction of the Terzo Valico dei Giovi high-speed railway line, focusing on the geological challenges encountered during tunnel excavation. Special attention is given to clay formations and complex tectonic zones that impact tunnel stability. The technical solutions adopted are described, including the use of high-performance steel ribs equipped with a semiautomatic locking system, designed to counteract rock mass pressures, mitigate risks, and ensure safety. These engineering solutions were applied for the first time globally in a delicate tectonic passage between the Alps and the Apennines, known as the Sestri–Voltaggio Zone. Monitoring data analysis is conducted to assess the effectiveness of the various engineering approaches. Finally, the document presents a repair intervention carried out on a tunnel section that sustained damage due to the use of a deformable rib, which proved unsuitable for this specific context.

Year 2025 will mark a turning point in the construction of the Mont Cenis base tunnel with the start of systematic tunnel boring machine (TBM) excavation, after awarding and start of the main works on the French and Italian sides in recent years. This step follows more than 20 years of studies and reconnaissance work, which have led to the creation of an exceptional project, which, once completed, will be the longest twin-tube railway tunnel in the world. The article first traces the study and reconnaissance phase, trying to show the complexity and considerable effort that was necessary to go forward with the current ongoing project. In particular, very significant means of study and reconnaissance were necessary to allow the start of the works in acceptable and controlled technical conditions. Then, the article presents the design choices that were made to address the technical challenges and requirements related to the expected functionality. In addition to the technical aspects and the vast range of complex situations that can be encountered, the main works were started following specific contractual models, aimed at a more equitable sharing of risks, in particular considering the impact of implementation times on the cost of the work. In conclusion, the main technical, environmental, and implementation challenges that characterize the project will be highlighted, making it unique and innovative. At the end of December 2024, the excavation progress for all works is 25 %.