The creep shrinkage of a salt cavern with constant gas pressures was studied. The gas pressures have constant values, but their positions (i.e. cavern radii) change with time, which is negligible for small deformations rather than for large deformations. Based on whether the displacement of the cavern wall is considered in boundary conditions, small and large deformation solutions for cavern creep shrinkage were developed. To validate the solutions, the analytical results were compared with the numerical results. The results of the large deformation solutions showed good agreement with the numerical results in the case of small and large deformations. However, the small deformation solutions only applied when their results were sufficiently small; otherwise, the cavern shrinkage was overestimated. In addition, the sensitivity of cavern shrinkage to factors, such as time, creep parameters, and the difference between the geostatic pressure and gas pressure (pressure difference), was discussed. In some cases, the results of the large deformation solutions showed that the cavern shrinkage grows over time at a declining rate instead of a constant rate. For caverns of rock salt with great creep parameters, such as D and n in the Norton power law, the cavern shrinkage was fast. The cavern shrinkage rate decreased as the pressure difference decreased. The minimum internal pressure obtained by the large deformation solutions was lower than that obtained by the small deformation solutions, which can help to reduce the cushion gas in salt caverns. The large deformation solutions can provide useful references for gas storage in salt caverns.

研究了在恒定气压下盐洞的蠕变收缩率。气压具有恒定值，但是它们的位置（即洞穴半径）会随时间变化，这对于较小的变形而不是较大的变形可以忽略不计。基于是否在边界条件下考虑洞壁的位移，提出了洞室蠕变收缩的大小变形解决方案。为了验证解决方案，将分析结果与数值结果进行了比较。大变形解的结果与小变形和大变形情况下的数值结果显示出很好的一致性。但是，小变形解决方案仅在其结果足够小时才应用。否则，洞穴收缩率被高估了。此外，讨论了洞穴收缩对时间，蠕变参数以及地静压力与气压之间的差异（压力差异）等因素的敏感性。在某些情况下，大变形解的结果表明，洞穴收缩随着时间的推移以下降的速率而不是恒定的速率增长。适用于蠕变参数较大的岩盐洞穴，例如在诺顿幂定律中，D和n的洞穴收缩很快。洞穴收缩率随着压力差的减小而减小。大变形解获得的最小内压低于小变形解获得的最小内压，这有助于减少盐洞中的缓冲气体。大变形解决方案可以为盐洞中的气体存储提供有用的参考。