Tunnel seismic detection methods are effective for obtaining the geological structure around the tunnel face, which is critical for safe construction and disaster mitigation in tunnel engineering. However, there is often a lack of accuracy in the acquired geological information and physical properties ahead of the tunnel face in the current tunnel seismic detection methods. Thus, we apply a frequency-domain acoustic full-waveform inversion (FWI) method to obtain high-resolution results for the tunnel structure. We discuss the influence of the frequency group selection strategy and the tunnel observation system settings regarding the inversion results and determine the structural imaging and physical property parameter inversion of abnormal geological bodies ahead of the tunnel face. Based on the conventional strategies of frequency-domain acoustic FWI, we propose a frequency group selection strategy that combines a low-frequency selection covering the vertical wavenumber and a high-frequency selection of anti-aliasing. This strategy can effectively obtain the spatial structure and physical parameters of the geology ahead of the tunnel face and improve the inversion resolution. In addition, by linearly increasing the side length of the tunnel observation system, we share the influence of the length of the two sides of the observation systems of different tunnels on the inversion results. We found out that the inversion results are the best when the side length is approximately five times the width of the tunnel face, and the influence of increasing the side observation length beyond this range on the inversion results can be ignored. Finally, based on this approach, we invert for the complex multi-stratum model, and an accurate structure and physical property parameters of the complex stratum ahead of the tunnel face are obtained, which verifies the feasibility of the proposed method.

隧道地震探测方法是获取掌子面周围地质构造的有效手段，对隧道工程的安全施工和减灾具有重要意义。然而，现有隧道地震探测方法对掌子面前方地质信息和物性信息的获取往往存在准确性不足的问题。因此，我们应用频域声学全波形反演 (FWI) 方法来获得隧道结构的高分辨率结果。讨论频率组选择策略和隧道观测系统设置对反演结果的影响，确定掌子面前方异常地质体的构造成像和物性参数反演。基于频域声学FWI的常规策略，我们提出了一种频率组选择策略，它结合了覆盖垂直波数的低频选择和抗混叠的高频选择。该策略可以有效获取掌子面前方地质的空间结构和物性参数，提高反演分辨率。此外，通过线性增加隧道观测系统的边长，分担了不同隧道观测系统两侧边长对反演结果的影响。我们发现，当边长约为掌子面宽度的五倍时，反演结果最好，超出该范围增加边测长度对反演结果的影响可以忽略不计。最后，基于该方法对复杂多地层模型进行反演，得到了掌子面前方复杂地层的准确结构和物性参数，验证了所提方法的可行性。