Abstract:

Ground freezing enclosure is a new technique that makes water in soil be ice by the way of artificial refrigeration, thus change original soil to be frozen retaining wall and waterproof curtain in foundation pit engineering. Based on the freezing principle, frozen soil curtain formed from aquifer has some super performances such as excellent waterproof, higher rigidity and strength, etc. As a new structure system of deep foundation pit in the large anchorage engineering, its important features include that piles and internal strut are used to be exterior-protected construction while frozen soil curtain hold back ground water. Compared with the conventional supporting projects, previous research data of frost mechanical properties in envelope works are always poor. Therefore frost heave mechanical characteristics of frozen curtain are obtained from simulation of three-dimensional coupling numerical nonlinear analysis of the fields of temperature and stress; and the conclusions are verified by field test data in foundation pit engineering. Research achievements may provide theoretical basis of applications in the future, not only for its rationality in analysis and results but also its reliability in techniques and methods.

Key words: frozen curtain, retaining structure, anchorage foundation, finite element analysis