Experimental Analysis of Influencing Factors on the Mechanical Deformation of Set Cement

This paper discusses the calculation of the deformability of set cement using experimental data, which are presently rare, obtained under different circumstances such as cement slurry formulation, experimental temperature, confining pressure, curing time and thickness of cement sheath. It shows that the elastic modulus of cement sheath is reduced by adding elastic and tough materials, and that a better mechanical deformability of cement sheath is obtained by adding latex than by adding cellulose. The elastic modulus of set cement decreases with an increase in curing temperature, and the total deformability of the cement sheath, at the same time, increases. An increase in confining pressure weakens the deformability of the set cement. The mechanical deformability of the set cement sheath, to some extent, increases with time. The thickness of the cement sheath has no effect on the property of the set cement, but a decrease in cement sheath increases the deformability of the set cement, by 85.5% at the most under the prevailing downhole condition presented in this paper.