基于高精度三维地震反射的水下隧道地质建模  

Application Research on Underwater Tunnel Geological Modeling Based on High Precision 3D Seismic Reflection

作　　者：李凯[1] LI Kai(China Railway Siyuan Survey and Design Group Co.Ltd,Wuhan,Hubei 430063,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,武汉430063

出　　处：《铁道工程学报》2024年第10期6-12,共7页Journal of Railway Engineering Society

摘　　要：研究目的:工程地质模型的构建主要依赖大量钻孔资料和地质测绘成果,而由点状信息构建的三维地质模型易出现数据分布不均匀、盲区大的特点,水域桥隧工程勘察工作以二维线状勘探为主,严重依赖钻探,存在成本高、周期长、作业风险大等问题,难以满足精细化、快速、高效地质建模需求。本文以甬舟铁路金塘海底隧道工程为依托,采用水域三维高精度地震反射波法对宁波端潜山发育区进行探测,充分利用地震反射地层解释、构造分析成果结合钻探数据通过井约束地质建模技术精确构建工区三维构造、属性地质模型,应用三维可视化技术实现工程实体与地质模型的融合分析,把复杂的地质构造与工程实体的空间关系表达出来,精确、立体地分析隧道洞身与地层、构造的接触情况,有效解决水域交通工程地质建模存在制约的问题。研究结论:(1)高精度三维地震反射勘探可以有效查明隧址区水底、第四系地层、下伏基岩(潜山)与不良地质构造(构造、破碎带)空间分布信息,为水域交通工程线状地质勘察提供了一种新思路;(2)三维地震反射勘探可以有效解决水域交通工程地质建模基础数据不充分、空间分布不均匀以及数据盲区问题,通过井约束地质建模技术可以有效提高建模精度,构建完整的水下空间地质模型,精确模拟地层、构造的形态、位置和空间接触关系,获得工区地层、构造和属性地质模型;(3)通过工程结构模型与精细三维地质模型融合分析,可以把复杂的地质构造与工程实体的空间关系通过三维可视化技术准确展示出来,直观分析隧道洞身岩土地质条件,为线路平纵断面设计方案优化、BIM设计、施工运维、风险决策提供可靠的依据和有力保障;(4)本研究结论可为水域工程勘察与地质建模提供参考。Research purposes:The construction of engineering geological models primarily relies on a large amount of drilling data and geological survey results.However,three-dimensional geological models constructed from point-based information often exhibit uneven data distribution and significant blind spots.Survey work for offshore bridge and tunnel projects predominantly relies on two-dimensional linear exploration,heavily dependent on drilling.This approach is characterized by high costs,long cycles,and high operational risks,making it challenging to meet the demands for detailed,rapid,and efficient geological modeling.This paper,based on the Jintang Subsea Tunnel Project of Ningbo-Zhoushan Railway,adopts the offshore three-dimensional seismic reflection method to explore the covered mountain development area in the Ningbo section.By combining stratigraphic interpretation and structural analysis results with drilling data,accurate three-dimensional structural and attribute geological models of the work area are constructed using well-constrained geological modeling techniques.Through three-dimensional visualization technology,the integration and analysis of engineering entities with geological models are achieved,expressing the spatial relationship between complex geological structures and engineering entities.Contact conditions between tunnel excavations and formations as well as structures are analyzed accurately and in three dimensions.This study effectively addresses the limitations of geological modeling in offshore transportation engineering.Research conclusions:(1)High-precision three-dimensional seismic reflection exploration can effectively identify spatial distribution information of the water bottom,Quaternary strata,underlying bedrock(covered mountain),and adverse geological structures(faults,fractured zones)in tunnel site areas,to provide a new approach for linear geological survey in offshore transportation engineering.(2)Three-dimensional seismic reflection exploration can effectively solve the problems

关 键 词：海底隧道 水域三维地震反射 地震解释 三维地质建模 隧道地质模型 

分 类 号：U25[交通运输工程—道路与铁道工程] P315.9[天文地球—地震学]