Average Temperature Model of Double-Row-Pipe Frozen Soil Wall by Equivalent Trapezoid Method

Average temperature is pre-requisite in obtaining the mechanical parameters and bearing capacity of frozen soil, and further evaluation of safety of the frozen soil wall could thus be made. This paper introduced Bakholdin's analytical solution for temperature field under double-row-pipe freezing and its correction when counting for the actual freezing temperature of soil. On the base of all these, an analytical model, namely equivalent trapezoid model was developed to calculate the average temperature of frozen soil wall under double-row-pipe freezing. This approach was to, on the base of Bakholdin formula and using equivalent trapezoid method, calculate the average temperature of a certain section which indicated the condition of the whole freezing soil wall. Furthermore, for possible parameter range of freezing tube layout might be applied in actual construction, this paper compared average temperatures of frozen soil wall obtained by the equivalent trapezoid method and by numerical integration of Bakholdin's analytical solution. The result showed that the discrepancy was small enough (<1.32%) to be ignored and the calculation accuracy of equivalent trapezoid method was competent for engineering practice.