盾构施工隧道不良地质聚焦电阻率与多频声波联合实时超前探测理论

Major disasters,such as water inrush and drift sand，surface subsidence and even machine crash，often occur in shield tunnel. because of the extremely complex environment，there is no used advanced detection method for unfavorable geology in shield tunnel both at home and abroad. The academic idea of “acoustic method to probe the three-dimensional position and spatial form of unfavorable geology, resistivity method to determine its water-bearing features and joint inversion to suppress multiplicity of solutions” is put forward in this project. Real-time advanced detection in shield tunnel is regarded as the main characteristic and difficulties .On the basis of giving consideration to other unfavorable geology, the interface between soft and hard layers, solitary rocks and hydrous karst caves are regarded as the main detective objects. First of all, the characteristics of both electric field and wave field will be studied respectively to propose the focused resistivity method and multi-frequency acoustic method which are integrated in shield machine for real-time advanced detection and the corresponding new observation mode. Secondly, the wavefield separation method and removal method for strong electromagnetic interference will be studied. The multi-frequency full waveform inversion theory and The three-dimensional inversion theory based on weighting function that are suitable for the complex environment in shield tunnel will be proposed. The joint inversion theory for real-time advanced detection method combined focused resistivity with multi-frequency acoustic in shield tunnel will be broken through. Finally, the real-time advanced detection method and technique combined resistivity with acoustic in shield tunnel will be established, which has great significance and value for the quantitative prediction of unfavorable geology under complex environment in shield tunnel and the disaster prevention and control.

城市地铁盾构施工经常遭遇涌水流沙、地表塌陷、盾构机械损坏等工程灾害，其主要原因是盾构施工环境极为复杂，国内外尚未有适合盾构施工不良地质超前探测的有效理论与方法。本项目基于“声波法探测不良地质体的三维位置及其空间形态，电阻率法判断其富水特性，二者联合反演压制多解性”的学术思路，以随盾构掘进实时探测为主要特色和难点，以软硬交替地层、孤石、岩溶富水空洞为主要探测对象同时兼顾其他不良地质。首先，提出盾构机载聚焦电阻率与多频声波实时超前探测方法与新型三维观测模式。其次，分别研究盾构施工复杂环境下声波探测的波场分离方法与电阻率探测的强电磁干扰去除方法，提出多频声波全波形反演理论与聚焦电阻率三维加权反演理论。然后，重点突破盾构施工多频声波与聚焦电阻率超前探测联合反演理论，最终形成盾构掘进机载声波与电阻率实时超前探测方法与技术，对解决盾构施工复杂环境不良地质的定量识别与灾害防治具有重要意义与价值。

城市地铁掘进机施工隧道经常遭遇突水涌沙、卡机、地表塌陷等灾害的威胁，其主要原因是掘进机施工复杂环境不良地质体探查困难。针对隧道掘进机复杂环境超前预报难题，本项目提出了一种基于波速与电阻率联合反演的机载聚焦电阻率与多频声波超前探测方法。针对含水体等不良地质体探测问题，提出了适用于掘进机隧道复杂环境的电阻率超前探测方法和聚焦测深型观测模式，进一步研究了电阻率探测的强电磁干扰去除方法，并建立了基于观测数据加权及深度加权函数的三维反演方法。针对断层破碎带等不良地质体探测问题，提出了适用于掘进机隧道超前探测的具有三向偏移距的观测模式，针对部分干扰波与有效波频谱成分接近问题，采用了f-k与τ-p联合滤波的方法，实现了隧道复杂波场反射波提取与干扰波的滤除，提出了多频声波全波形反演理论与方法。在电阻率与声波探测的基础上，提出了掘进机隧道施工多频声波与聚焦电阻率超前探测联合反演理论与解译准则，通过开展大量物理模型试验与现场试验，最终形成掘进机机载声波与电阻率超前探测技术，研究成果对隧洞不良地质的超前探测与灾害防治具有重要意义。