Summary: | 碩士 === 國立成功大學 === 土木工程學系碩博士班 === 101 === The geological storage of CO2 is a technique to reduce greenhouse gas emissions. To estimate the storage pressure of a CO2 geological storage site, we must evaluate the in-situ stresses of reservoir rock. Acoustic Emission (AE) and Deformation Rate Analysis (DRA) are new core-based techniques to measure the pre-stress of the rock. However, the applicability of AE and DRA on the pre-stress evaluations is different from rock to rock and must be checked. In addition, the CPC indicates that Yutengping sandstone at Tieh-chan-shan is a potential site for CO2 geological storage in central Taiwan. Thus, cyclic loads are applied on the sandstone specimens to memory the pre-stress to the specimens. Then, AE and DRA are applied to the pre-stressed samples to estimate the pre-stress. In the practical applications, delay time can be defined as the time, from which the specimens taken in-situ site to the laboratory. Therefore, the impact of different delay time on the accuracy of pre-stress evaluations must be discussed. The study found that Yutengping sandstone is classified as a weak rock. The Kaiser Effect of AE method on the Yutengping Sandstone is insignificant. But, DRA estimates the pre-stress of the sandstone with the error less than 20%. Additionally, the estimated pre-stress of Yutengping sandstone decreases as the delay time increases.
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