ABSTRACT
hyperTunnel’s method aims to substantially change tunnelling and underground construction, contributing a solution that is envisaged to be more sustainable and cost effective. The method works by turning convention on its head; building structures prior to excavation and use - in-situ tunnelling. Through a unique combination of proven technologies – including digital twins, robotics, 3D printing and digital underground surveying, supported by AI and VR – hyperTunnel’s approach aims to redefine the possibilities in underground construction. Two such existing technologies, permeation and compaction grouting, are established means of ground consolidation and groundwater ingress mitigation. The hyperTunnel method builds on these by tailoring them for a detailed and controlled underground construction process. Geotechnical assessment of the ground’s properties, both pre- and post-deployment of grout, is used to evaluate and develop the novel construction process. To generate samples, deployments are conducted in ground chambers of various sizes (≥1 m3) resulting in grout “plumes”. The size, weight and shape of plumes create a unique challenge to traditional cube and cylindrical sampling. Samples of the virgin ground and post-deployment composites are tested for their material properties. Testing includes, but is not limited to, particle size distribution, shear box, consolidation, uniaxial compression, modulus of elasticity, Poisson’s, in-direct tensile, density and permeability. The consistency and repeatability of the post-deployment product is evaluated to inform design assumptions and provide insight to computational modelling. Application aside, the overall process and data provide insight into the properties of grouted ground, away from more idealised and controlled desktop environments. The outlined geotechnical process underpins the thorough, empirical approach to design assurance adopted by hyperTunnel in its design and construction methodology.
