隧道GNSS施工控制网复测若干问题探讨

隧道GNSS施工控制网是保证隧道准确贯通的基础,施工过程中要对其进行周期性复测,确保其成果的稳定性,但目前没有一套合适的复测成果可靠性评价指标可供参考。利用多个已建成和在建隧道施工控制网测量实践数据,对隧道施工控制网的复测方法、复测精度、控制点稳定性评价指标等问题进行分类统计比较和分析探讨,提出采用绝对位置法与相对关系法相结合的综合判断法甄别不稳定控制点,并给出控制网复测精度及控制点稳定性判别指标,为隧道GNSS施工控制网复测标准修订提供借鉴参考。

Discussion on Repetition Survey of Tunnel Construction GNSS Control Network

GNSS control network for tunnel construction is to ensure accurate holing-through of a tunnel and it needs to be periodically rechecked in the tunneling period to ensure the stability of the survey results,but by far,there are no reference indexes for reliability evaluation of the checked results. Based on the data measured by the control survey networks from several completed tunnels and tunnels underconstruction,repetition survey method,repetition survey accuracy,stability evaluation indexes for control point survey are classified and analyzed. The results show that the comprehensive evaluation method in combination with absolute position method can be employed to identify unstable control points and provide indexes for evaluation of repetition survey accuracy and control point stability,and provide reference for revising the repetition survey criterion of GNSS control network for tunnel construction.