Effects of Material Parameters on Stress Distribution in Casing-cement-formation(CCF)Multilayer Composite System  

作　　者：Chao ZHANG Yuanbo XIA Bo ZHOU Xiuxing ZHU Haijing WANG 

机构地区：[1]College of Pipeline and Civil Engineering,China University of Petroleum(East China),Qingdao,Shandong,266580,China [2]School of Petroleum Engineering,China University of Petroleum(East China),Qingdao,Shandong,266580,China [3]CNPC Tianjin Bo-Xing Engineering Science&Technology Co.,Ltd.,Tianjin,300451,China

出　　处：《Mechanical Engineering Science》2023年第2期8-16,共9页机械工程（英文）

基　　金：the Independent Innovation Research Program of China University of Petroleum(East China)(Grant No.27RA2215005);the National Key Research and Development Program of China(Grant No.2017YFC0307604).

摘　　要：This work focus on the stress distribution of the casing-cement-formation(CCF)multilayer composite system,which is a borehole system with multiple casings and cement sheathes.Mostof the previous relevant studies are based on the traditional CCF system with the single casing and cement sheath,but these results are not adaptive to the CCF system multiple composite system.In this paper,the FEM numerical model of CCF multilayer composite system was constructed.Numerical simulations were calculated and compared with the system which consists of the single casing and cement sheath.Results show that the multilayer composite system possesses better performance.On this basis,the sensitivity analysis of main influence mechanical parameters such as in-situ stress,the elastic of cement sheathes and the elastic of formation are conducted.The cement sheath on the inside,namely cement sheath-1,is sensitive to its elastic modulus;meanwhile,the cement sheath on the outside,namely cement sheath-2,is not so sensitive to the elastic modulus of cement sheath-1.Cement sheath-1 and cement sheath-2 are all sensitive to the elastic modulus of cement sheath-2,and the mises stress of them has opposite trend to the elastic modulus of cement sheath-2.The proper values of elastic modulus of cement sheath-1 and cement sheath-2 are 5GPa and 5GPa to 30GPa,respectively.Under the in-situ stress ratio σh/σH=0.7,the maximum mises stress of cementsheath-1 and cement sheath-2 increase as the increase of σh,and they are nearly equal when σh=15GPa.This research can be helpful for the design and analysis of CCF multilayer composite system.

关 键 词：In-situ stress Stress distribution CASING Cementsheath FORMATION MULTILAYER 

分 类 号：TB3[一般工业技术—材料科学与工程]