地下水封液化石油气(LPG)洞库建成验收后，要对洞罐的容积进行测量。为了测量结构复杂的黄岛50万m3LPG地下水封洞库的库容容积，首先，确定测量模型，把组成洞库的单个洞室或巷道定义为特殊尺寸的隧道并作为测量单元，分析断面测量过程中影响库容容积精度的因素；其次，探讨高精度自动测量Ⅰ级全站仪、隧道断面测量系统和三维实体建模软件的组合应用，根据采集的断面点集数据，通过人工计算和建模自动计算的相互验证，并与第三方成果对比分析；最后，创建洞库三维模型，水平剖切得到规定要求的一定深度容积计量表、切片图和洞库三维模型切片储量报告。结果表明： 采用断面法测量洞库库容是一种比较可行的测量方法，易操作，能保证精度要求。

The storage capacity of underground liquefied petroleum gas (LPG) watersealed cavern has to be measured after acceptance. In this paper, the measuring model of Huangdao underground LPG watersealed cavern is decided； and then the factors effecting the storage capacity of cavern during crosssection measurement are analyzed; the combination application of Grade I highprecision automatic total station, tunnel crosssection measuring system and 3D entitative modeling software is discussed; the artificially calculated results and the modelling automatic calculation results based on data collected are compared with results from the third party. Finally, a 3D model of the cavern is established； and a series of achievement is obtained. The results show that the crosssectional measuring method is feasible and convenient, and it can meet the precision requirements of storage capacity measurement.