放射線を利用した地中水分および密度の原位置計測について : 鹿島神之池附近のモデルテスト

概要

論文の詳細を見る
The authors did a field experimant by way of the neutron moisture meter (Hitachi PB-1 style) & γ-ray density meter (Hitachi PG-3 style) in the visinity of Lake konoike, Kamisu Village, Ibaraki Prefecture, in order to put the instruments to practical use. The experimant using and γ-ray proved effective in measuring water content in soil through the following three procedures which were deviced by authors. At first they dug bore holes (7m deep with the diameter of 85mm) and inserted an iron pipe (diameter 57mm) into the holes, then let the neutron probe hang down to the bottom. To exclude water which interevened between a pipe and the wall of the hole, they tried several technical devices so that natural status of stratum may reflect directly to the neutron apparatus. 1) Driving method. The end of an iron pipe was sharpened and the pipe was allowed to be driven with a hammer under the bottom of holes as deep as 60cm. This is the most correct measuring method, because stratum approaches to the probe nearer, but it is a defect that a pipe is difficult to be driven, as stratum becomes harder. 2) C Cl_4 method. It is a method which eliminates water intervened between a pipe and the wall of a bore hole on account of the larger density of C Cl_4 (1.49), but it is a weak point that C Cl_4 penetrates into sandy bed and is difficult to revise. 3) Packer method. A gum tube is put over an iron pipe which is inserted bore-holes to the botom, then compressed air is sent through the pipe, making the gum tube swell towards the wall of a bore-hole. Afterwards the apparatus is hung down to measure. This is capable to use in a harder ground as well, but it has the defect of destroying a bore-hole. Calibration was carried out in June. A drum was field with dried sand, and water being poured step by step, and probe was inserted into the sand for measuring; at the same time moisture content in the sand was estimated at 105℃ in an oven of the loboratory. Thus calibration curves of practical use were obtained.
一般社団法人日本応用地質学会の論文
1967-06-01

放射線を利用した地中水分および密度の原位置計測について : 鹿島神之池附近のモデルテスト

スポンサーリンク

概要

著者

関連論文

スポンサーリンク