Project Name:   Pista Nueva Malaga High Speed Rail Tunnel

Location: Malaga, Spain

Application: Precast Segmental Tunnel Lining

A Joint Venture of Acciona Infrastructures and Sando Construcciones were awarded the construction of the suburban rail line by AENA. The extension to Malaga airport required an investment of Euro 280 million. The Los Prados-Airport section runs almost entirely below the surface, crossing under the Guadalhorce River and Malaga Airport’s new runway. The name of the tunnel is “Túnel Guadalhorce-Aeropuerto”. It is an electrified double track tunnel and is part of “La línea C-1 de Cercanías Málaga”, between Málaga and Fuengirola.

• Ground conditions: Alternating gravel, sand and clay layer
• Alignment length: 2900m; Depth=15-28m
• TBM type: Operating thrust=8500-36600kN; Maximum theoretical thrust=83643kN

Design Approach Adopted

• Design method & standard used: Spanish code EH-91
• Specified Strengths: 50 N/mm2, Flexural tensile strength= 5 N/ mm2, Residual Strength= 2.9 N/mm2
• Inner and outer diameter: ID 8,43 m, OD 9,07m
• Ring segmentation: 6 segments + 1 trapezoidal key
• Dimensions of segments: Segment Width: 1,5 m, Thickness: 0.320m,
• Type of segment reinforcement: Hybrid: macro synthetic fibre & steel bar

Outcomes:

• Hybrid solution significantly reduced total volume of steel in the segment
• Reduced required concrete cover to remaining steel bar
• Increased crack control within the segments
• Minimized spalling in handling and installation
• Increased bursting resistance under jacking loads
• Pista Nueva Malaga is referenced in ITA’s ITAtech Guidance for Precast Fiber Reinforced Concrete Segments Vol 1 Design Aspects

Author:  Geoff Sedgman: gsedgman@elastoplastic.com