所定の透水係数を有するベントナイト混合土の配合設定方法

概要

論文の詳細を見る
Bentonite/Sand Mixture is expected to be an effective component of barriers for radioactive waste facilities. Several effective characteristics of Bentonite/Sand Mixture are 1) low permeability, 2) self-healing, 3) long-term durability. Low-permeable mixture can be obtained through enrichment of bentonite content of the mixture. But the data of relation between bentonite content and permeability have been taken in few kinds of sand, therefore we cannot estimate the appropriate arrangement of mixture in case of using another kind sand. On the other hand there is no guiding principle regarding which sand is better for making low-permeable mixture. Compaction tests and permeability tests were executed in order to research the method how to choose the better sand and to decide the appropriate bentonite content. First we made many kinds of Bentonite/Sand Mixture using 3 kinds of sand in 3 or 5 cases of varied bentonite content, and measured the permeability in laboratory. The difference of permeability between 3 kinds of sand was not negligible in spite of same bentonite contents, especially in condition of poor bentonite content. Then we examined the relation between permeability and effective void ratio which is calculated from bentonite content and density of the mixture. The effective void ratio is useful parameter for choosing better sand and for deciding optimum mixture. We propose the following procedure for designing the Bentonite/Sand Mixture. 1) To examine the conditions of maximum dry density through compaction test using few kinds of candidate sand and varied bentonite content. 2) To calculate effective void ratio from maximum dry density and plot the relationship between bentonite content and effective void ratio of each candidate sand. 3) To decide the optimum effective void ratio for the target permeability according to the relation between permeability and effective void ratio. 4) To decide the optimum bentonite content of each candidate sand according to the relation curve between bentonite content and effective void ratio. 5) To choose several cases of potential mixture design. 6) To examine not only permeability but also mechanical properties of the chosen mixture design. 7) To choose the best mixture design.
日本粘土学会の論文
1994-09-27

所定の透水係数を有するベントナイト混合土の配合設定方法

スポンサーリンク

概要

著者

関連論文

スポンサーリンク