An Analytical Solution for Microannulus Cracks Developed Around a Wellbore

Abstract

In situations like blowout or hydraulic fracturing, excessive fluid pressure may cause leaking in the casing in shallower parts of the formation. The resulting high pressure may form a cylindrical crack around the wellbore. An analytical solution for stress distribution and displacement along a cylindrical crack formed between the casing and the formation is provided in this paper. The crack is assumed to be opened by uniform fluid pressure exerted on both sides of the crack. This solution has a wide range of applications from failure analysis of fibers in manufacturing composite materials to wellbore integrity in petroleum and subsurface engineering problems.