大巴山某隧道超前预报涌水段判识特征研究

发布时间：2018-05-09 11:57

本文选题：突涌水 + 地质雷达　；参考：《成都理工大学》2015年硕士论文

【摘要】：随着交通、水利水电等国家基础设施建设重心逐渐向地质条件极端复杂的西部地区和岩溶山区转移,隧道与地下工程的建设规模以及难度成倍增加,在工程建设方面我国将面临诸多挑战,尤其是被称为世界级工程难题的隧洞突涌水灾害治理。据统计,全国范围内,由突涌水灾害及处置不当造成的安全事故占到隧洞工程建设事故的80%。突涌水灾害往往导致重大人员伤亡、经济损失与工期延误,有的隧道甚至被迫停建或改线。此外,突涌水灾害若不能有效治理,极易诱发水资源枯竭、地表塌陷等环境地质灾害,严重威胁社会稳定与经济发展。因此,在开挖过程中隧道前方掌子面进行准确的超前地质预报,对减少施工事故,保证施工人员生命安全和施工进度具有十分重要的意义。但是目前人们对地质雷达系统的成果解释仍以人为经验为主,缺乏相关的解译标志,往往造成物探预报的“一图多解”,因此深入研究地质雷达探测不良地质体的特征,建立预报解释结果一般规律,对提高地质雷达探测的精度和准度有着举足轻重的作用。本文以大巴山某涌水隧道为工程实例,通过对大量隧道超前预报结果进行分析,提取了地质雷达频谱在本段围岩的一般规律;结合本段围岩物探探测结果的一般规律,针对隧道的异常涌水段提出专项预报方案;根据隧道的地质勘察资料、隧址及周边的水文地质条件,结合实际的涌水特征,分析了隧洞发生涌水的原因;根据地下水赋存空间以及运动规律提出隧道的涌水处治措施;最后对比分析隧洞注浆前后涌水量变化评价治理效果,本论文取得的主要成果包括:(1)从地质雷达和TSP的探测原理出发,根据隧道地质条件,探讨了在探测过程中参数取值。(2)通过大量的隧道超前预报地质雷达探测结果,对页岩段的裂隙及含水层进行对比分析,找出了地质雷达在该段探测解译的一般规律。裂隙段:反射波波形较杂乱,振幅变化大,相位交替出现,并伴有绕射、散射等现象;在频谱图上表现为高频(100MHz)为主,幅值较宽,在主频附近常常伴有多个小峰值。富水段:电磁波传播速度较低,产生强发射波,有时也会产生绕射、散射现象;在灰度图像上电磁波波幅较饱满、圆润,常常能见连续振幅;随着含水量的增加,雷达主频逐渐降低,由多峰逐渐向单峰转变,在渗水段频谱图像表现为以低频(25MHz)为主,频谱峰值以孤立形式出现,中高频部分逐渐减弱,高频部分已趋于消失。(3)对隧道的异常涌水段,采用了TSP、地质雷达以及红外探水相结合的综合预报方法,TSP探测显示掌子面后方围岩整体较破碎,地质雷达的主频为15MHz,比渗水段的雷达主频更低,红外探水显示该段存在异常场,对比综合预报结果,推测掌子面后方的基本围岩情况:节理裂隙发育,地下水发育,含水量较掌子面略有增加。(4)通过对研究区的宏观地质条件、地形地貌、隧洞突涌水的特征以及隧洞开挖揭露的地质资料、超前预报探测结果分析研究,找出了隧洞异常突涌水段的原因:隧道洞身上方雨水充沛,地表水丰富,有充足的补给水源;隧道异常突水段处于褶皱核部挤压破碎带,受构造应力影响,隧洞围岩节理、裂隙发育,为地下水富集提供了广泛的存储空间;根据掌子面开挖揭露的围岩特征,围岩裂隙贯通,相互连通性较好,提供了地下水的运移通道。(5)在介绍了常用的隧洞突涌水治理方法体系以及治理原则的基础上,确定了本隧洞突涌水治理采用“以堵为主”的方针,结合其他隧洞工程治理经验,提出了采用超前帷幕预注浆法来治理本隧道突涌水段以及提出注浆参数。采用水泥-水玻璃浆液,全断面注浆,注浆单孔有效扩散半径为2m,注浆初始压力为1.0MPa,终压2.0MPa,注浆堵水加固有效范围为开挖轮廓线外5m,开挖掌子面均匀布置三环注浆孔,环向间距均为2m,一次注浆长度15m,每次开挖12m,留3m作为下一循环注浆止浆盘,单孔注浆量7.8m3。隧洞注浆前涌水量约为7000m3/d,注浆后隧洞涌水量约为450m3/d,隧道涌水灾害治理效果明显,验证了采用超前帷幕预注浆技术在治理本隧道裂隙段突涌水的有效性。
[Abstract]:With the transportation, the center of infrastructure construction, such as water conservancy and hydropower, is gradually shifting to the extremely complex geological conditions in Western and karst mountains. The construction scale and difficulty of tunnel and underground engineering has multiplied. In the construction of engineering, China will face many challenges, especially the flood disaster of tunnel, which is called the world class engineering problem. According to statistics, according to statistics, in the whole country, the 80%. sudden water gushing disaster, which is caused by inrush water disaster and improper disposal, often leads to heavy casualties, economic loss and time delay, and some tunnels are even forced to stop or change lines. In addition, the sudden water inrush disaster can be easily induced if it can not be effectively treated. It is easily induced. Environmental geological disasters such as water resource exhaustion and surface collapse seriously threaten social stability and economic development. Therefore, it is of great significance to reduce construction accidents and ensure the safety of construction personnel and construction progress. The interpretation of the results of the system is still based on human experience and lack of relevant interpretation marks. It often causes "one picture and multiple solutions" of geophysical prediction. Therefore, it is very important to study the characteristics of geological radar to detect bad geological bodies and establish the general rules of the prediction interpretation results. This paper plays an important role in improving the accuracy and accuracy of the geological radar detection. Taking a flood tunnel in dababan as an example, through the analysis of a large number of tunnel forecast results, the general rule of the geological radar spectrum in the surrounding rock is extracted, and a special forecast scheme is put forward for the abnormal water gushing section of the tunnel according to the general law of the geophysical prospecting results of the surrounding rock, and the tunnel is based on the geological survey data and the tunnel. At the site and the surrounding hydrogeological conditions, combined with the actual water gushing characteristics, the causes of the water gushing in the tunnel were analyzed. The water gushing treatment measures were put forward according to the groundwater storage space and the law of movement. Finally, the effects of water inflow change before and after the tunnel grouting were compared and analyzed. The main achievements of this paper include: (1) from geology Based on the detection principle of radar and TSP, according to the geological conditions of the tunnel, the parameters of the parameters in the detection process are discussed. (2) through a large number of tunnels ahead of the prediction of the geological radar detection results, the fracture and aquifers in the shale section are compared and analyzed, and the general law of the interpretation of the geological radar in this section is found out. Chaos, amplitude change, phase alternately, accompanied by diffraction, scattering, and so on. On the spectrum, it is characterized by high frequency (100MHz), wide amplitude and often accompanied by a number of small peaks near the main frequency. The water rich section is low in electromagnetic wave propagation, produces strong emission waves, and sometimes produces diffraction and scattering phenomena; electromagnetic waves on grayscale images The amplitude of the wave is full and rounded, and the amplitude of the frequency is often visible. With the increase of water content, the main frequency of radar gradually decreases, and the frequency spectrum of the seepage section is mainly at low frequency (25MHz), the peak frequency of the spectrum appears in isolation, the middle and high frequency parts gradually weaken and the high frequency part tends to disappear. (3) the abnormal surge to the tunnel. In the water section, the integrated prediction method of TSP, geological radar and infrared water exploration is adopted. The TSP detection shows that the surrounding rock in the rear area of the palm is broken, the main frequency of the geological radar is 15MHz, which is lower than the main frequency of the radar in the water seepage section. The infrared water exploration shows the existence of the abnormal field, and the basic surrounding rock behind the face of the palm face is speculated. Conditions: joint fissure development, groundwater development, water content a little increase compared with the palm surface. (4) through the macroscopic geological conditions of the study area, topography and geomorphology, the characteristics of the tunnel gushing water and the geological data of the tunnel excavation revealed by the tunnel excavation, the analysis and study of the advance prediction results have been made, and the reason for the abnormal sudden water gushing section of the tunnel is found out: the square rain on the tunnel hole body is found. The water is abundant, the surface water is abundant and the water supply is sufficient. The abnormal water burst section of the tunnel is in the crush zone of the wrinkle core, which is influenced by the tectonic stress, the tunnel rock joints and the cracks develop, which provide a wide storage space for the groundwater enrichment. According to the characteristics of the surrounding rock revealed by the excavation of the palm face, the surrounding rock cracks are through and the interconnectedness is better and provides better interconnectedness. (5) on the basis of introducing the commonly used method system and the principle of controlling the water gushing of the tunnel, the principle of "blocking the main" in the treatment of the water inrush in the tunnel is determined, and combined with the experience of other tunnel projects, it is proposed to use the pre curtain grouting method to control the water inrush section of the tunnel and to lift the water inrush section of the tunnel. With the grouting parameters, the cement water glass slurry, full section grouting, the effective diffusion radius of the grouting single hole is 2m, the initial grouting pressure is 1.0MPa, the final pressure is 2.0MPa, the effective range of grouting reinforcement is 5m outside the excavation contour line, the three ring grouting holes are evenly arranged in the face of the excavation, the circumferential distance is 2m, the length of grouting is 15m, each excavation 12M, and 3M each time excavation. As the next Grouting grouting disc, the water inflow of the 7.8m3. tunnel before grouting with single hole grouting amount is about 7000m3/d, the water gushing amount of the tunnel after grouting is about 450m3/d, and the effect of tunnel water gushing disaster treatment is obvious. It is proved that the effectiveness of the pre grouting technique of the front curtain is used to control the water inrush in the tunnel section.

【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U452.11

【参考文献】