Lisbon new circular metro line: interconnection section between new line and existing terminus




Lisbon new circular metro line: interconnection section between new line and existing terminus


The new Lisbon metro line will cross a densely urbanized part of the city, connecting Rato station located at one of the hills of the city and Cais do Sodré station at Tagus River right bank. The interconnection between the new line and the existing terminus is located close to the Tagus River bank where the landfill and clayed soft soils rasting over the Miocene bedrock have more than 20m thickness. Given this geotechnical scenario and the constrains related to the densely urbanized area, the cut and cover excavation solutions have been designed to minimize the surrounding ground perturbance and surface settlements. Diaphragm walls braced by steel struts were used to hold a 20m depth excavation. The connection was materialized by the existing wall demolition and the simultaneous construction of a new structural system inside the terminus structure. This intervention included the construction of new reinforced concrete beams and columns with a meticulous construction phasing aligned with the demolition works using as well temporary support systems. The complexity of those works was increased by the constrains inside the terminus where the impact on Metro circulation should be minimized. This paper presents an overall description of the adopted solutions, how they were implemented as well as the monitoring plan that allowed the risk management of those complex works.

P. Marques; C. Martins; Catarina Fartaria; R. Tomasio; A. Pinto


18th European Conference on Soil Mechanics and Geotechnical Engineering (ECSMGE2024)



D - Current and new construction methods