Geotechnical Assessment of Compacted Sand Bentonite Mixtures to be Utilized in Underground Nuclear Waste Repositories and Barrier Design

Abstract

This study assesses the mechanical and hydrological performance of compacted sand bentonite mixtures to be utilized in sealing underground nuclear waste repositories. In order to assess the performance of this material and to obtain an optimum sand bentonite mixture, a variety of laboratory tests, namely, compaction, falling head permeability, swelling, unconfined compression and shear strength tests were performed on sand bentonite mixtures possessing bentonite contents ranging from 5% to 15%. Sand bentonite barrier design was performed for the optimum seal selected as a function of the axial stress applied to the barrier and barrier length-to-radius ratio (L/a).

Keywords

• Sand bentonite mixture,nuclear waste disposal,barrier design

Yeraltı Nükleer Atık Haznelerinde Kullanılabilecek Sıkıştırılmış Kum Bentonit Karışımlarının Geoteknik Değerlendirmesi ve Bariyer Tasarımı

Abstract

Bu çalışmada, yeraltı nükleer atık depolama haznelerinin sızdırmazlığının sağlanması için geoteknik ve hidrolojik açıdan sıkıştırılmış kum bentonit izolasyon malzemesi tasarlanması amaçlanmaktadır. Optimum karışım miktarını belirlemek için %5 ile %15 oranları aralığında bentonit içeren kum bentonit karışımları üzerinde kompaksiyon, düşen seviyeli hidrolik iletkenlik, şişme basıncı, serbest basınç ve basit kesme deneyleri yapılmıştır. Seçilen optimum kum bentonit bariyer karışımının tasarımı, bariyere uygulanan düşey gerilmenin ve bariyer yükseklik-yarıçap oranının (L/a) fonksiyonu olarak yapılmıştır.

Keywords

• Kum bentonit karışımı,nükleer atık depolaması,bariyer tasarımı

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