Abstract
A great number of drifting woods, which occur and run off at heavy rains, should be checked at the suitable place of the upper reaches of river, in connection with blockade problem caused by them at the lower reaches. There are some methods to check the drifting woods, in which the stockade for drifting woods is worth investigating. In this paper we introduce some methods and then describe the results of some measurements on the moving form the group of drifting wood which approach to the stockade, as the first stage of a series of study on the check of drifting woods.
