Hyperloop Challenge

Project Description

The British Tunnelling Society decided to investigate the Tunnelling Challenges of Hyperloop.   London Bridge Associates was commissioned by the BTS to carry out a research study and produce a report for publication.   A key element in the study was a workshop of industry experts who gathered partway through the study to make their experience and expertise available to the study team and to help to shape the recommendations for future industry action.

The initial study and the first sections of the report investigated already-published material on Hyperloop as an engineering concept being developed in various ways but not specifically for use in tunnels.   This characterisation study sets the scene and provides the engineering and scientific background which must be recognised before considering the Tunnelling challenges.

After establishing the characteristics of Hyperloop, likely tunnel sizes, possible lengths, depths, curvature and alignment were considered.   It was demonstrated that Hyperloop tunnels would need to be long, very nearly straight, and capable of being driven through the prevailing geology. 

Tunnelling expertise addressed the specific challenges of driving long tunnels in varying ground conditions, noting a range of technical challenges and drawing on past project experience.

To bring focus to the challenges, a model tunnel was defined that matched the engineering requirements of Hyperloop to the human and physical geography of the UK.   The model tunnel was defined in sufficient detail to provide a basis for costing.   The results of the costing exercise were shown in the context of two relatively recent widely used benchmarking studies for tunnels in the UK and Europe.   

Partway through the study an interim report was circulated to a range of industry experts from government, clients, academia, learned societies, designers, contractors, TBM suppliers, materials suppliers and other specialists prior to their participation in a facilitated workshop.  Some of the primary themes developed in the workshop were:

• Reduce non-tunnelling costs (e.g. people, parties, planning approval)
• Fully automated, continuous mining and lining
• Recycle spoil
• Extruded ‘non-concrete’ linings that are crack free and self-healing.
• Develop single pass concrete extruded tunnel linings that are crack free and self-healing.  
• Change procurement model to improve incentive towards common goal of faster, lower cost tunnelling with innovation.

Arising from the consideration of these themes, a number of recommendations were made for actions that could usefully be taken forward with an identification of the most likely means of achieving progress in the necessary improvement of efficiency and reduction in tunnelling costs. 

A number of technologies that have already been used but are not yet mainstream tunnelling methodologies were investigated and reported, together with some wider technological advances from other industries which may offer opportunities for significant increase in tunnelling efficiency.