Metro Line 6

The São Paulo Metro Line 6-Orange, developed by Acciona, is currently one of the largest infrastructure projects in Latin America. The line will extend 15.3 km with 15 stations, connecting the Brasilândia district in the north to São Joaquim station in the city center. The main benefit is a significant reduction in travel time—from approximately 1 hour and 30 minutes by bus to around 23 minutes by metro.The project includes the excavation of twin metro tunnels using two TBMs. In addition to civil works, it encompasses railway systems, signaling, power, and urban modernization. Social inclusion and sustainability initiatives were also integrated, such as workforce training and environmental impact mitigation. Completion is expected in 2026, with a projected daily ridership of approximately 630,000 passengers.

Sika has been a key partner in the success of this project, providing technical support and specially developed products and systems for TBM excavation, concrete production, waterproofing, sealing, bonding, and concrete repair—enabling efficient, safe, and minimally disruptive execution of Line 6-Orange for the people and city of São Paulo, Brazil.

The construction of the São Paulo Metro Line 6-Orange stands out due to the use of advanced construction methods and cutting-edge technologies to tackle the challenges posed by such a large-scale project. Specifically, it addresses highly complex geological and urban conditions along its route. The main methods and techniques employed in this project are detailed below:

Tunnel Excavation with Tunnel Boring Machines (TBMs)
For the excavation of the 15.3 km of tunnels, EPB TBMs with diameter of 10.6 meters were used. These machines have enabled underground excavation with minimal surface interference, ensuring precision and safety. By January 2025, over 13 km of tunnels had been completed, with TBMs reaching excavation rates of up to 41 meters of tunnel in 24 hours. This high performance was made possible by Sika solutions for TBMs, which include foaming agents, polymers, admixtures, and greases.

Station Excavation Methods
The stations along the line were built using different excavation techniques, selected based on factors such as available space, schedule, cost, and geological conditions:

• Open Cut (VCA): A method where excavation starts from the surface, creating a large open pit. Once internal tructures are completed, the space is covered, and the surface is restored. Stations such as Brasilândia, Vila Cardoso, Santa Marina, Sesc-Pompeia, and Perdizes used this method.

• Top-Down Open Cut: Like the traditional Open Cut method, but construction of slabs and structures occurs from top to bottom. This allows access ramps for heavy equipment, speeding up excavation of the lower levels. This method was used at Santa Marina Station.

• New Austrian Tunneling Method (NATM): A method involving sequential tunnel excavation, allowing precise control in geologically complex terrains. This technique was applied at stations such as Itaberaba, João Paulo I, Freguesia do Ó, Água Branca, PUC-Cardoso de Almeida, Angélica-Pacaembu, Faap-Mackenzie, Bela Vista, and São Joaquim.

Ventilation Shafts and Emergency Exits
Beyond the stations, the project includes the construction of ventilation shafts and emergency exits. In some areas, such as north of VSE Tietê, additional shafts were excavated and connected by NATM tunnels. This adaptation was necessary due to the specific geological characteristics of the region, allowing the tunneling to reach more stable rocky terrain.

General Challenges
Overall, the depth of the stations and adaptation to complex geological profiles under tight schedules were among the main challenges of the São Paulo Metro Line 6 project. Some stations are notable for their depth. Higienópolis-Mackenzie Station, for example, will be the deepest in the São Paulo metro system, reaching 69 meters below the surface. This depth increased the complexity of construction, requiring advanced excavation, structural reinforcement, and waterproofing techniques, for which state-of-the-art Sika solutions were adopted.During excavations, sandy soils and water flows were encountered, posing extreme challenges. In these cases, the team modified construction methods, implementing soil stabilization techniques to ensure safety and work continuity. Operationally, large-scale equipment was mobilized for TBM assembly and operation, including cranes with capacities of up to 1,000 tons. These cranes were essential for installing heavy TBM components, such as the cutterhead, which is fundamental for excavation progress.

Tunnel Boring Machine (TBM) Solutions

• Sika® Sigunit®-3100 L BFG
  Accelerator admixture for backfilling grout
  
• SikaTard®-3100 BFG
  Retarder admixture for backfilling grout
• Sika® Stabilizer-1514 TBM
  Foaming agent with anti-clay polymer to prevent clogging in cohesive soils
• Sika® Stabilizer-1111 TBM
  Foaming agent for non-cohesive abrasive sandy soils
• Sika® Stabilizer-2231 TBM
  Pumping grade tail sealant grease
• Sika® Stabilizer-3710 TBM
  Super water absorbent polymer for critical water presence situations and lack of fines
• Sika® Stabilizer-1516 TBMFoaming agent with lubricating and anti-wear properties, for hard rock rock excavation

Concrete Solutions

• Sika® ViscoCrete®-20 HE
  RA-2: Type 2 Water Reducer/Superplasticizer for high early strength concrete
• Sika® Desmoldante
  Release agent for absorbent forms
• Sika® Separol® BIO
  Release agent for metal forms – precast segments
• Sika® Separol®-100 W
  Release agent for absorbent forms
• Sika® Antisol® Pav
  Curing agent
• Sika® Rugasol®-200
  Surface setting retardant

Tunnel and Station Waterproofing

• Sikaplan WP 1100-30HL
  PVC membrane for waterproofing underground structures

General Solutions

• Sikaflex® PRO-3
  PU sealant with high chemical resistance for aggressive environments
• Sika Repair®-222
  Thixotropic single-component repair mortar
• SikaGrout®-250
  Fluid cementitious grout for structural repairs
• SikaTop®-122 Plus
  Repair mortar with corrosion inhibitor
• SikaBond® PVA
  High-performance polymer adhesive for bonding layers and mortar
• Sika MonoTop®-100 Seal
  Single-component semi-flexible waterproofing coating
• Sika® Injection-101
  Open-cell PU foam for temporary sealing
• Sika® Injection-201
  Closed-cell PU resin for permanent sealing