• Application of a Bingham viscoplastic model to borehole closure: comparison between two numerical approaches 

      Xie, Xiyang; Fjær, Erling; Detournay, Christine (Chapter, 2019)
      ABSTRACT: Several field observations by cement bond logs (a technique used to detect substance behind casing) indicate progressive borehole closure in soft rock such as shale. This study considers the problem of progressive ...
    • Can Heating Induce Borehole Closure? 

      Xie, Xiyang; Bauer, Andreas; Stenebråten, Jørn; Bakheim, Sigurd; Lavrov, Alexandre; Fjær, Erling; Kristiansen, Tron Golder (Peer reviewed; Journal article, 2020)
      The current study shows that heating a cased borehole in low-permeability shale rock can induce plastic deformation, leading to the closure of the casing annulus and decreasing annulus connectivity. The thermally induced ...
    • Experimental design and mathematical simulation of hookload while tripping through bends. 

      Xie, Xiyang (Master thesis, 2015)
      To meet the growing demand of energy consumption, oil companies are trying their best to produce oil. However, in the past few years, the oil price has kept going down and dampened the whole industry. On one side, oil ...
    • Long-term creep prediction with a modified power law model 

      Xie, Xiyang; Fjær, Erling; Pradhan, Srutarshi (Chapter, 2017)
      Creep in weak rock is a common phenomenon observed in the laboratory. Based on short-term creep, prediction of long-term creep can be a challenge especially at elevated stress levels, since only a small stress increase may ...
    • Third-order elasticity of transversely isotropic field shales 

      Bakk, Audun; Duda, Marcin; Xie, Xiyang; Stenebråten, Jørn; Yan, Hong; MacBeth, Colin; Holt, Rune Martin (Peer reviewed; Journal article, 2023)
      The formations above a producing reservoir can exhibit large mechanical changes, creating a risk of significant subsidence and loss of rock integrity. These changes can be monitored by time-lapse seismic acquisition, which ...
    • Time-dependent closure of a borehole in a viscoplastic rock 

      Xie, Xiyang; Fjær, Erling; Detournay, Emmanuel (Journal article; Peer reviewed, 2019)
      The paper describes a model to predict and analyze the time-dependent closure of a borehole drilled in a soft rock subjected to an initial isotropic stress, and the build-up of stress on a rigid casing after contact with ...
    • Time-Dependent Deformation of Rock Around a Borehole 

      Xie, Xiyang (Doctoral theses at NTNU;2019:281, Doctoral thesis, 2019)