Technical Assistance and Works Supervision for the B-25 Dual Carriageway

Developer: Ministry of Transport and Sustainable Mobility
Location: Baix Llobregat region, Barcelona
Year: 2008 – 2026

Connectivity and Territorial Cohesion in Baix Llobregat

The extension of the Baix Llobregat Dual Carriageway —officially designated as the B-25— represents a key infrastructure project for mobility in the Barcelona metropolitan area. Designed to directly connect the A-2 dual carriageway with the C-32 motorway and the C-31c, this intervention resolves a long-standing congestion bottleneck in the municipalities of Sant Boi de Llobregat, Cornellà de Llobregat, and El Prat de Llobregat.

This Completion Project updates the original 2008 construction design to provide a definitive response to the section's technical, regulatory, and operational viability. SOCOTEC is involved by providing Technical Assistance and Works Supervision, ensuring compliance with safety regulations, rigor in construction procedures, and the environmental optimization of the works.

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Oscar Bustos

Director Obras de Barcelona - Infraestructuras del Transporte

Barcelona

Director Obras de Barcelona - Infraestructuras del Transporte

Cohesion and Sustainable Mobility

The solution adopted in the completion project directly addresses the territory's strategic operational and social needs:

Elimination of congestion bottlenecks: Unblocks the direct branch of the Cornellà Interchange (A-2 to C-245) and streamlines access to nearby industrial parks, such as Les Salines and the La Parellada area.
Improvement of heavy and industrial traffic: The reconfiguration of merging and diverging lanes at the Sant Boi South interchange (around structure E-15) optimizes the safe merging of heavy vehicles coming from the Agricultural Park.
Urban integration and accessibility: The new grade-level roundabout at the Sant Boi North interchange improves connectivity with the town center and enables traffic movements that were previously restricted, featuring a layout specifically designed to accommodate heavy-goods and oversized vehicles.
Promotion of active mobility: Integrates the new E-08 structure, which carries the B-25 dual carriageway over the BV-2002 and safely incorporates a cycle path and pedestrian walkway.
Development of the El Prat Central Business District (Centro Direccional): The reorganization of the perimeter road network provides the necessary access routes for future urban and commercial development between El Prat de Llobregat and the Ronda de Ponent.

Esquema B25

Services for Civil Engineering Projects Site Supervision Services

Key Interventions and Structural Upgrades

The project encompasses the conversion of a 2.3 km section of the former C-245 and A-16 roads into a dual carriageway (2 to 4 lanes in each direction) with a design speed of 80 km/h.

Following several preliminary analyses regarding the original design's regulatory compliance, significant technical changes were made relative to the original 2008 project and its Revision No. 1.

01 / 05

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The solution adopted in this Completion Project demonstrates how the technical revision of historical designs leads to more efficient, safe, and environmentally friendly outcomes. Our technical assistance and works supervision on the B-25 ensures the flawless execution of complex interventions —such as the jacking and reinforcement of existing structures or the implementation of the new Sant Boi North roundabout— guaranteeing the continuity of local traffic and the highest construction quality.

David Lozano, Head of Technical Assistance and Works Supervision – SOCOTEC Site Director

SOCOTEC’s Expertise in Technical Assistance and Road Infrastructure

With an extensive track record in supervising major public works, SOCOTEC has established itself as a strategic partner for public administrations and private developers in the transport infrastructure sector.

Our Capabilities in Road Projects

Quality Control and Works Supervision: Continuous monitoring of construction processes, material acceptance, and execution tracking for structures, pavements, and drainage systems.
Non-Destructive Testing (NDT) and Geotechnics: Soil characterization, monitoring of complex foundations in river environments, and structural health monitoring of viaducts and underpasses.
Management of Amendments and Technical Adjustments: Critical analysis of construction projects to optimize alignments, minimize impacts on utility networks, and adapt to updated road regulations.
Road Safety Audit and Multimodal Mobility: Integration of solutions for public transport corridors, cycle lanes, and pedestrian connectivity in suburban environments.

Geotechnical Services Testing Laboratories

Connectivity and Territorial Cohesion in Baix Llobregat

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