Effects of Long-Term Exposure to Ultrahigh Temperature on the Mechanical Parameters of Cement

摘要

Long-term mechanical durability of a cement sheath exposed to stresses in a wellbore environment is critical to maintaining zonal isolation for the life of a well.The ability of a cement sheath to remain intact when exposed to changing wellbore stresses is highly dependent upon the parameters of Young's Modulus,Poisson's Ratio and tensile strength of the cement and the surrounding rock.Wellbore stresses sufficient to cause failure of a cement sheath may result from changes in temperature,casing pressure,formation pressure,or near-wellbore tectonic stresses.