Geomechanical modeling and the casing stability analysis in conditions of cement stone partial absence

Abstract

As part of this work, a numerical finite element model of the near-wellbore zone was developed, including its main structural elements and an area with no cement stone. On the example of the achimov deposits of one of the oil fields of the Khanty-Mansiysk autonomous region, multivariate modeling of the stress-strain state of the near-wellbore zone under conditions of poor-quality cementing was performed. It was revealed that the angular component of stresses has the maximum values in the casing. It is shown that the most probable destruction of the production casing is possible when pressure is not applied in the area of the zone with absence of cement. It is determined that the fracture zones of the column occur for the angle of the area with absence of cement from 25° to 110°, while these areas are characterized by maximum, both tensile and compressive stresses. Keywords: casing; cement stone; elastic-strength properties; near-wellbore zone; numerical model; finite element method; stress-strain state.