COLLAPSE RESISTANCE OF OIL WELL CASING-CEMENT MANTLE COMBINATITON SUBJECTEDTO NON-UNIFORM LOADING BY ROCK CREEP
油井套管、水泥环组合体抗非均匀围岩外载的强度特性

In recent years,many oil well casings have been collapsed due to creep of viscoelastic rocks.In thispaper,the formulas of calculating stresses in the casing,under the condition of the casing-cement mantlecombination subrcted to four types of non-uniform creep loading,is derived by means of complex function method in Elastic Mechanics,Using the formulas, the strength of the combination under the fourtypes of loading is analyzed by calculating the casing wall stresses,and the effect of the elastic andgeometric parameters of the casings and cement mantles on the strength is also studied. Some importantresults are obtained in this study,and it would have a great value for the design of the oil well casing increep formations.