Frost heave performance of a foundation at an overhead transmission line in the alpine seasonal frozen regions

Abstract

The Manzhouli 500 kV electrical transmission line travels more than 218 km through seasonal frozen regions, which result in many freezing soil engineering problems with respect to the transmission tower foundations. Physical model tests of independent reinforced concrete foundations at various temperatures were conducted and verified by numerical simulation to investigate the frost-heaving characteristics of the reinforced concrete foundation in an alpine seasonally frozen region. The evolution of the temperature field, frost-heaving force, and water migration of frozen soil were studied in an open water refill environment with a dead load. The heave force in the foundation soil increases as temperature decreases. The horizontal heave force in the middle and upper parts of the foundation can reach 540 kPa. However, the maximum tangential frost-heaving force becomes 3.83 kN, and the maximum frozen depth of the frozen soil was 240 mm. During the freezing process, the frost heave of the foundation was significantly more noticeable. The correlation between experimental and simulated values is good, and each parameter’s variation error is less than 5 %. Finally, control measures of frost heave were proposed to guide engineering practice based on experimental and numerical studies.