Preliminary Performance Assessment of the Engineered Barriers for a Low- and Intermediate-Level Radioactive Waste Repository

Experimental Study on the Thermal Conductivity of Compacted SPV200 Bentonite

“…In the density range of 1.4 g/cm 3 to 1.7 g/cm 3 , the thermal conductivities of SPV 200, MX80, and GMZ bentonites fall in the lower group, ranging from 0.44 W/m•K to 0.70 W/m•K, while that of FEBEX, Kyeongju, and KV1 bentonites are in a somewhat higher group, ranging from 0.61 W/m•K to 0.89 W/m•K. [11,16,[38][39][40] Figure 12 plots the relationship between measured thermal conductivity and water content of various bentonites compacted to a constant density of 1.6 g/m 3 . It is noticed that the thermal conductivity of bentonite spans over a broader range of 0.4 W/m•K to 1.5 W/m•K for the varying water contents from 5% to 26%.…”

“…Apparently, increased dry density will reduce the porosity and improve the contact conditions between bentonite particles. However, bentonites with higher water content indicates that more voids are filled with water, which is more efficient in heat conduction [30,[39][40][41][42]. The data in Figure 12 show that the thermal conductivities of most bentonites are very close at varying water content levels, with the KV1 bentonite having slightly higher thermal conductivity than others.…”

“…Figure 11. Thermal conductivity vs. dry density relationship for various compacted bentonites [11,16,[38][39][40]. …”

An Analysis of the Factors Affecting the Hydraulic Conductivity and Swelling Pressure of Kyungju Ca-Bentonite for Use as a Clay-Based Sealing Material for a High-Level Waste Repository

“…The hydraulic conductivities of the bentonite-sand mixture and the clay-crushed rock mixture increase with an increasing sand/crushed rock (aggregate) content [4,16,22,23]. The existence of a threshold inert material content that brings about a sharp increase of hydraulic conductivity has also been reported Different Samples) [8,21] [24].…”

“…It has been reported that the swelling pressure of bentonite increases with an increasing dry density of bentonite [13,23,40,41]. When the dry densities were 1.4 to 1.8 Mg/m 3 , the swelling pressures of Kyungju Cabentonite were in the range of 647 kPa to 14,070 kPa and increased with an increasing dry density [39].…”