Study of statistical law on over-under-excavated values of highway tunnel

In ordr to provide the reasonable parameters in the reliability analysis of tunnel structure and the criterion in the quality control of tunnel engineering, in this paper, the over-under-excavated values of the real-state outline of tunnl excavation are obtained by the nera-field photographic method. By using mathematical statistic method, the figure features and probability distributions of the over-under-excavated values of the surrounding rock,including deferent positions of same cross section, are analyzed.