为研究垂直水幕对扩建地下水封油库布局方式的影响，以某大型地下水封洞库分期建设工程为依托，采用有限元数值模拟方法，对有、无垂直水幕条件下扩建洞库的布局方式进行研究。研究结果表明： 1）当两期洞库间距较小时，在两期洞库之间设置垂直水幕可有效削弱拟建洞库对已建洞库水封可靠性的影响，随两期洞库间距的增加，垂直水幕的影响性逐渐减弱； 2）拟建洞库轴线方向对水封可靠性的影响受地形等条件的影响较大，在两期洞库之间设置垂直水幕对水封可靠性的影响较小； 3）随拟建洞库埋深的增加，拟建洞库的水封可靠性逐渐增强，已建洞库的水封可靠性却呈逐步减小趋势，在两期洞库之间设置垂直水幕可有效减小埋深对两期洞库水封可靠性的影响。

The finite element numerical simulation method is used to study the layout modes of the cavern enlargement with and without vertical water curtain system by taking a largescale underground watersealed oil storage cavern as an example. The study results show that: (1) When the distance between two caverns constructed at different time is small, the vertical water curtain system can effectively reduce the influence of the proposed cavern on the watersealed reliability of the completed one; with the increase of the distance between the two caverns, the influence of the vertical water curtain gradually weakens. (2) The influence of the axial direction of the proposed cavern on the watersealed reliability is greatly affected by the terrain; moreover, in this case the vertical water curtain system has less influence on the watersealed reliability. (3) With the increase of the depth of the proposed cavern, the watersealed reliability of the proposed cavern gradually increases, while the watersealed reliability of the completed cavern decreases gradually; the vertical water curtain system between the two stages of the caverns can effectively reduce the effect of the depth on the watersealed reliability.