Integrated Experimental and Numerical Evaluation for Wellbore Integrity of Wells under Downhole Conditions
Abstract
Cement sheath integrity is a critical part of maintaining wellbore integrity during the wellbore lifecycle and needs to be thoroughly investigated under representative downhole conditions. This paper utilizes an integrated experimental and numerical approach to investigate the cement hardening process and evaluate the severity of wellbore damage under downhole conditions for the entire wellbore lifecycle. The integrated approach includes data collection for downhole conditions and a staged Finite Element Analysis (FEA) framework to evaluate cement failure occurrence. The modeling results indicate that the state of stress developed in the cement after hardening fundamentally affects cement failure occurrence under various loads. The integrated approach indicates that the cement strength decline due to degradation affects the onset of failures (i.e., debonding, radial cracks, and disking) significantly; excessive shrinkage during cement hardening promotes onset of debonding failure which largely endanger the wellbore integrity in the long-term. In summary, to obtain a robust evaluation of wellbore integrity, a systematic evaluation of the cement hardening process and the associated parameters considering downhole conditions where the cement is actually used is suggested. A cement system with less shrinkage, lower Young's modulus, and higher strength can effectively improve wellbore integrity.
Recommended Citation
W. Zhang et al., "Integrated Experimental and Numerical Evaluation for Wellbore Integrity of Wells under Downhole Conditions," 55th U.S. Rock Mechanics / Geomechanics Symposium 2021, vol. 3, pp. 755 - 764, American Rock Mechanics Association, Jan 2021.
Department(s)
Geosciences and Geological and Petroleum Engineering
Second Department
Civil, Architectural and Environmental Engineering
International Standard Book Number (ISBN)
978-171383912-5
Document Type
Article - Conference proceedings
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 American Rock Mechanics Association, All rights reserved.
Publication Date
01 Jan 2021
Comments
Center for Creative Photography, University of Arizona, Grant None