/Hybrid Tunnel Boring Using Combination Of Thermal And Mechanical Processes
Abstract

Novel hybrid tunnel boring methods, systems, and apparatuses are described. Example hybrid methods integrate (a) thermal processing, e.g., preconditioning and/or thermal spallation (which may be used as pre-treatment), and (b) mechanical processing while boring tunnels in rock and other formations. Thermal processing and mechanical processing may be used alternatively or simultaneously. For example, the preconditioning may use thermal energy to induce thermal shock and weaken the rock (e.g., cause expansion stress, micro-fractures, thermal spallation, etc.). This preconditioning changes the relevant properties of the rock relative to the additional (e.g., mechanical) excavation, including, among other things, effective compressive stress, abrasion properties, and hardness. This preconditioned rock can therefore be efficiently removed using mechanical drilling tools, resulting in, for example, faster boring speeds, reduced tool wear, enhanced precision, and longer deployment lengths (e.g., in comparison to conventional TBM and especially MTBM approaches).

Full Text

What is claimed is:

Novel hybrid tunnel boring methods, systems, and apparatuses are described. Example hybrid methods integrate (a) thermal processing, e.g., preconditioning and/or thermal spallation (which may be used as pre-treatment), and (b) mechanical processing while boring tunnels in rock and other formations. Thermal processing and mechanical processing may be used alternatively or simultaneously. For example, the preconditioning may use thermal energy to induce thermal shock and weaken the rock (e.g., cause expansion stress, micro-fractures, thermal spallation, etc.). This preconditioning changes the relevant properties of the rock relative to the additional (e.g., mechanical) excavation, including, among other things, effective compressive stress, abrasion properties, and hardness. This preconditioned rock can therefore be efficiently removed using mechanical drilling tools, resulting in, for example, faster boring speeds, reduced tool wear, enhanced precision, and longer deployment lengths (e.g., in comparison to conventional TBM and especially MTBM approaches).
Timeline
Filed
06/12/2026
Published
10/01/2026
Granted
Not Available
IPC Codes(1)
E21D 9/10:Making by using boring or cutting machines (takes precedence E21D 9/08; similar machines for mining E21C 27/20; mining picks E21C 35/18)