The line heat source methodof soil moisture monitoring requires higher heating power. When the intensityof the heat source is unstable

the monitoring results are easily affected. Tosolve the shortcomings of the line heat source method

a mobile point heatsource (PHS) method for soil moisture monitoring is developed in this study.This method uses the correlation between the thermal physical properties ofsoil and the moisture content to indirectly identify the moisture content bymonitoring the cooling law of the PHS in the soil. Firstly

the heat transferlaw of the PHS in the soil with evenly distributed moisture content wasexamined through numerical simulation. According to the characteristics of thecooling curves of the heat source

the moisture content discrimination index was defined

and then the fitting relationship betweenthe moisture content and the discrimination index was established. In addition

parameter analysis was carried out on the factors affecting the monitoringsensitivity. Then

numerical simulation of the PHS cooling law was carried outin the soil with unevenly distributed moisture content

and the moisturecontent discrimination index was calculated according to the time history curveat the cooling stage of the measuring point. After that

the moisture contentdistribution was inverted by the fitting formula of the moisture content andthe discrimination index. The results show that the moisture contentdistribution inverted by the PHS method is in good agreement with the actualvalue

which verifies the theoretical feasibility of the method. Finally

thefeasibility of the method is further verified by model tests.