Single heater test results and implications for nearfield processes

摘要

The Single Heater Test (SHT) is being conducted in the exploratory Studies Facility at Yucca Mountain,Nevada as an integral part of the U.S.Department of Energy's program of testing and studies to evaluate its suitability for a potential repository for the permanent disposal of spent nuclear fuel and high-level nuclear waste.The main objectives of the SHT,the first in situ thermal test in the proposed repository horizon of welded Topopah Spring Tuff,are: a) to measure rock mass thermal and thermomechanical properties; b) to evaluate the various instruments and measuring ssystems to be employed in the much larger drift Scale Test; and c) to better understand the coupled thermal-mechanical-hydrological-chemical processs in the local rock mass surrounding a fully-loaded repository.As shown in Figure 1,the 13mx10mx 13m test block is bounded by the observation drift to the north,the thermomechanical alcove to the west and the thermomechanical alcove extension to the south.The 4 kW,5-meter-long rod heater is emplaced in a east-west horizontal borehole such that its end is approximately 2 meters from the west face.Forty additional boreholes were drilled for various measuring systems.The configuration and instrument layout of the SHT is described in the Single Heater Test Status Report [1].