ABSTRACT
Artificial Ground Freezing (AGF) is a favoured method for temporary ground support in cross passage construction between tunnels in soft soils, noted for its structural stability and water tightness. This paper addresses a notable gap in AGF optimization from a construction perspective, by delineating critical design considerations. The design of AGF’s configurations range from dual-sided with standard collars to minimal collar, each influencing pipe length, number, and installation angles. Reducing collar height optimizes these variables, decreasing both material costs and project duration. Lining type selection is crucial, with considerations extending to spatial constraints posed by traditional reinforced concrete segments. Steel linings can be proposed as an alternative, facilitating improved load transfer and minimizing internal temporary support for spaceproofing. The use of nitrogen as a freezing agent, offering substantial reductions in freezing time compared to brine, is evaluated against safety risks and cost. The goal of this paper is to present a comprehensive framework for integrating design considerations for AGF, and discuss their practical implications in a construction context.
