Thermal property is one of the basic physical properties of rock and soil

and it is widely used to evaluate the retention

conduction and distribution of the heat. Thermal conductivity

specific heat capacity and thermal conductivity are the most common parameters

and they are also used in geothermal energy management and development

engineering freezing excavation and construction design in cold areas. The existing studies have shown that soil thermal parameters are associate to some factors such as the soil types

source

water content

density. In this study

the thermal parameters of silty clay and clay at a construction site in Zhanjiang

Guangdong province were tested. The results show that with increasing water contents

the thermal conductivity and thermal diffusivity of silty clay increase to a maximum value and then decrease

while the specific heat capacity increases linearly. The effect of dry density on thermal conductivity of silty clay depends on the moisture. When the water content is less than 20.0%

the thermal conductivity increases with the increase of dry density

while the water content is over 27.5%

it decreases with the increase of dry density. At the water content of about 24.5% (liquid limit)

there is no law to follow. The effect of dry density on thermal diffusivity of silty clay is not obvious. Both the thermal conductivity and specific heat capacity of clay increase with the increase of water content and dry density. As the water content increases

the thermal diffusivity increases nonlinearly until it is stable. Under a low water content

the dry density does not significantly affect the thermal diffusivity; however the thermal diffusivity increases firstly and then decreases with increasing dry densities under the high water content. In addition

it is also found that the existence of large particles can cause the thermal conductivity of silty clay to be more complicated than that of clay.