Frost jacking characteristics of prefabricated cone cylindrical tower foundation in cold regions

The foundations of high-voltage transmission lines in permafrost areas are often affected by frost heaving of the soil, which leads to engineering accidents, such as falling towers or poles. The tower foundation type that has been analyzed thus far cannot meet the construction requirements well. Based on research on the prefabricated cone cylindrical (PCC) tower foundation model, indoor model tests were conducted to study the frost jacking characteristics of the tower foundation under different temperatures. The temperature field distribution char-acteristics and the pattern of the frost jacking displacement were determined, and the anti-frost jacking mech-anism of the PCC tower foundations was analyzed. The research indicates that the following. (1) The PCC tower foundation, which combines the structural characteristics of a tapered column foundation and prefabricated foundation with the technical advantages of frost resistance and easy construction. (2) The freezing rate de-creases exponentially with time, and the frost jacking displacement increases in an S shape. (3) The mechanical conditions for the displacement of the foundation was proposed based on the mechanical analysis. (4) To pro-mote economy and safety, a foundation engineering design criterion has been proposed for burying the upper surface of the foundation below the freezing depth line, which can prevent engineering accidents.

Automated summary

Based on research on the prefabricated cone cylindrical (PCC) tower foundation model, indoor model tests were conducted to study the frost jacking characteristics of the tower foundation under different temperatures. The research indicates that the PCC tower foundation combines the structural characteristics of a tapered column foundation and prefabricated foundation, and has good frost resistance and easy construction. A foundation engineering design criterion has been proposed for burying the upper surface of the foundation below the freezing depth line to prevent engineering accidents.