Soft rock tunnels constructed in mountainous areas frequently encounter complicated geological environments, variable geo-stress fields, notable anisotropic and time-dependent deformation of layered rocks, and universal corrosive conditions of the support system, which causes numerous tough issues during the construction and operation of tunnels.

There are three main challenges related to the deformation control and long-term safety assessment of soft rock tunnels in mountainous areas. Firstly, the strong crustal movement forms an uneven and locally concentrated high geo-stress. The stress redistribution after tunnel excavation often introduces excess stress in the surrounding rocks, which exceeds the rock strength and leads to the occurrence of tunnel squeezing deformation. Secondly, metamorphic and sedimentary rocks with well-developed weak planes are widely distributed, which shows evident anisotropy in mechanical and physical behaviour and has a complicated nonlinear evolution process with damage, cracking, and collapse after tunnel excavation. Thirdly, the supporting structures are prone to corrosive deterioration due to the high-stress, high-temperature, and high-pressure environment, which causes the failure of structures with the increase of time

The aim of this Special Issue is to bring together original research and review articles highlighting the squeezing deformation control technologies and long-time performance evaluations of tunnel structures. We particularly welcome submissions related to the interaction mechanism between soft rocks and supporting structures, the design and analysis of novel tunnel structures, corrosive behaviour of cables and steel arches, the fracture evolution of surrounding rocks after tunnel excavation, etc.

Potential topics include but are not limited to the following:

• The strain soften features and constitutive models of rocks
• The creep behaviour and constitutive models of rocks
• Multiphysics and multiscale behaviour of rocks
• Finite element, finite difference, discrete element, and coupled numeric modelling approaches
• Design and analysis of different tunnel structures, such as yielding structures, support with high stiffness
• Strain localization theory of geomaterials
• The new measuring technologies recording the mechanical behaviour of rocks and supporting systems
• The use of artificial intelligence algorithms in evaluating the long-term safety of tunnels
• The corrosive behaviour of rock bolts under tensile, shear, or combined actions
• The corrosive features of steel arches or reinforced concrete under compression, bending, or combined action
• The determination of in-situ geo-stress field