二等水准联测技术在区域似大地水准面精化中的应用研究

Research on Application of Second-Order Leveling Joint Survey Technology in Regional Quasi-Geoid Refinement

摘要: 二等水准测量是区域似大地水准面精化工作中不可或缺的外业环节，该类观测工作技术门槛高、精度约束严格，同时野外作业工作量大，实施条件艰苦。如何在满足规范精度阈值的前提下优化作业模式、提升项目实施效率，是开展似大地水准面精化项目时需要重点考量的现实问题。本文以某市似大地水准面精化工程为例，对测区内现存三等水准控制点开展外业检测，同步完成水准路线每千米偶然中误差验算。检测结果表明，部分原有三等水准点各项指标均可达到二等水准技术条件。基于该前提，将检测合格的三等水准点用作高程传递节点，充分挖掘已有三等水准观测成果的价值，参与二等水准网构网与整体平差解算。工程实践证明，该技术手段能够有效压缩外业施测规模，在保障成果质量的同时提升作业效率，可为国内同类型似大地水准面精化工程项目提供实践参考。

Abstract: Second-order leveling is an indispensable field operation in regional quasi-geoid refinement, characterized by high technical requirements, stringent precision constraints, substantial field workload, and harsh operating conditions. Optimizing operation modes and implementation efficiency while meeting specified precision thresholds is therefore a key practical concern in such projects. Taking a municipal quasi-geoid refinement project as an example, field inspections were conducted on existing third-order leveling control points, and the accidental mean square error per kilometer of leveling routes was verified through computation. Results show that some original third-order leveling points fully meet second-order leveling specifications. These qualified points were adopted as elevation transfer nodes and incorporated into the network formation and overall adjustment computation of the second-order leveling network. Engineering practice demonstrates that this approach effectively reduces field survey scale, improves efficiency while ensuring result quality, and provides practical references for similar domestic quasi-geoid refinement projects.