Research in the Relation between Frost-heaving of Forest Road and Conditions of Road Surface

In order to research in the relation between frost-heaving of forest road and conditions of road surface, we set two experimental places, shade and sunny. And allocated six test sections in each place. The items of six test sections were ① removed snow, ② untouched, ③ paved 15cm depth with graved, ④ laid vineyl mat, ⑤ paved 50cm depth with graved and ⑥ sprinkled with water. further, we buried four sensoers of temperature in road at 15cm and 50cm depth in each place. We measured the frost-heaving height and temperature of each point at intervals of about 10 days from late in December to early in April. As a result, it appears follows. 1. At the sections paved 50cm depth with graved, the frost-heaving hight was less than 2cm. 2. At the sections sprinkled with water, the frost-heaving was higher than at the untouched sections. 3. At the sections removed snow and laid vineyl mat, it appeared reverse resalts between two experimental places concerning frost-heaving. 4. The temperature of 50cm depth was higher than VC during this winter. Between the temperature of 15cm depth and the frost-heaving hight, no relation was shown. 5. At the hide place, the frost-heaving was higher and the period of frost-heaving was longer than at sunny place.Article信州大学農学部演習林報告 29: 147-157(1992)departmental bulletin pape