In this study, based on the measurement data and the records of Takamatsuzuka Tumulus in the past, the effects of excavation and preservation measures after the excavation on hygrothermal behavior in the stone chamber of Takamatsuzuka tumulus are analyzed by means of numerical simulation. The obtained main results are shown as follows:
1. Before the excavation, the annual amplitude of temperature in the stone chamber is small and relative humidity keeps nearly 100% throughout the year, and there are few dryness and condensation occur on the inside surface of the stone chamber.
2. After the excavation, if there are no any preservation measures taken, the temperature in the stone chamber rises to 22°C in summer, and there are obviously durative dryness and condensation on the inside surface of the stone chamber.
3. The method by covering the exposed surface of the stone chamber with certain thickness of soil is more effective on restraining the temperature rise in the stone chamber and dryness on the inside surface. However, there are no finer effects on restraining condensation both on the north wall and nearby floor in summer.
