Abstract
The slope stability of soft to semi-hard rocks has a close relation with the weathering of composing rocks. Auther surveyed the weathering of aged stone buildings such as ancient tombstones, and have been studying on the weathering mechanism and weathering speed of various kind of rocks. As the first step, obtaind results are as follows.
1. The rate of surface weathering on stone buildings differs with each direction of their face, and then it is evidently larger on the south face or the west. It seem that this weathering rate depent on the deger of temperature difference on their surface.
2. The defect by weathering on the surface of stone buildings is the maximum in depth at the place of 20-30 cm above their bacement. This defect is estimated to be related with reflection of heat, Jumping of rain water, etc. from basement stone or road surface.
3. The rate of weathering depends on property of rocks. The weathering defect extendery to 0.5 cm in depth from the surface requires a period of about 20 years on the rock having 100 kg/cm2 of uniaxial compressive strength (dry), and a period of about 900 years on the rock of 2, 000 kg/cm2.
