技术领域technical field
本发明涉及隧道安全监测技术领域，具体为一种基于光纤与模拟技术结合的隧道变形监测方法。The invention relates to the technical field of tunnel safety monitoring, in particular to a tunnel deformation monitoring method based on the combination of optical fiber and simulation technology.
技术背景technical background
随着我国地铁、高铁及高速公路里程的不断增加，各种山体、地下隧道也快速增加，不良地质体等外界条件给隧道的安全运营带来较大风险，隧道变形监测越来越收到重视。传统隧道变形监测需要在隧道运营窗口，对隧道监测点进行人工监测，即便部分如三维激光扫描、缺乏时效性、安全性，并且不能对隧道内部的微变行进行有效捕捉，无法评估隧道微变形给隧道带来的风险，缺乏及时的对隧道全断面结构安全性进行准确的预警手段，给隧道的安全运营带来一定的风险。With the continuous increase of the mileage of my country's subways, high-speed rails and expressways, various mountains and underground tunnels have also increased rapidly. External conditions such as adverse geological bodies have brought greater risks to the safe operation of tunnels, and tunnel deformation monitoring has received more and more attention. . Traditional tunnel deformation monitoring requires manual monitoring of tunnel monitoring points in the tunnel operation window, even if some parts, such as 3D laser scanning, lack timeliness and safety, and cannot effectively capture the micro-deformation lines inside the tunnel, and cannot evaluate tunnel micro-deformation The risks brought to the tunnel, the lack of timely and accurate early warning means for the safety of the tunnel's full-section structure, brings certain risks to the safe operation of the tunnel.
虽然存在部分利用光纤/栅传感器进行隧道变形监测的技术，但是其监测需要人为判断是否存在变形风险，智能化程度较低，或者通过人为设定变形上限进行自主判断，但是未与隧道所在地形等条件结合，误判风险较大。Although there are some technologies that use optical fiber/grid sensors for tunnel deformation monitoring, their monitoring requires human judgment on whether there is a risk of deformation, and the degree of intelligence is low, or the upper limit of deformation is artificially set for independent judgment, but it is not compatible with the terrain where the tunnel is located. Combining conditions, the risk of misjudgment is greater.
发明内容Contents of the invention
针对现有技术的不足，本发明提供了一种融合光纤与模拟技术的隧道全断面变形监测预警方法，以解决现有技术中隧道地下空间变形监测智能化程度低及误判风险大的问题。Aiming at the deficiencies of the prior art, the present invention provides a tunnel full-section deformation monitoring and early warning method that integrates optical fiber and simulation technology to solve the problems of low intelligence and high risk of misjudgment in tunnel underground space deformation monitoring in the prior art.
技术方案如下：The technical scheme is as follows:
本发明提供了一种融合光纤与模拟技术的隧道全断面变形监测预警方法，其特征在于，该方法包括：The invention provides a tunnel full-section deformation monitoring and early warning method that integrates optical fiber and simulation technology, which is characterized in that the method includes:
步骤1、收集隧道所在区域地质水文资料及隧道结构资料建立数值模型；Step 1. Collect geological and hydrological data and tunnel structure data in the area where the tunnel is located to establish a numerical model;
步骤2、将建立的数值模型网格化后导入FLac3D岩土数值模拟软件建立三维数值模拟模型，所述三维数值模拟模型中：地层强度准则选用摩尔库伦模型，衬砌结构选用壳结构模型；Step 2, gridding the established numerical model into FLac3D geotechnical numerical simulation software to establish a three-dimensional numerical simulation model, in the three-dimensional numerical simulation model: the Mohr Coulomb model is selected as the stratum strength criterion, and the shell structure model is selected for the lining structure;
步骤3、获取隧道所在区域各地层的岩土体物理学参数并给步骤2所得三维数值模拟模型赋值，取合适的边界条件，进行初始平衡计算；Step 3. Obtain the rock and soil physical parameters of each layer in the area where the tunnel is located and assign values to the three-dimensional numerical simulation model obtained in step 2, and take appropriate boundary conditions to perform initial balance calculations;
步骤4、根据隧道实际工况对步骤3所得三维数值模拟模型进行隧道模型开挖，得到隧道模型，在所得隧道模型表面利用壳单元模拟衬砌结构，得到衬砌结构模型，根据工程资料获取隧道衬砌结构物理学参数并对衬砌结构模型赋参，然后再次进行初始平衡计算；Step 4. Excavate the tunnel model of the 3D numerical simulation model obtained in step 3 according to the actual working conditions of the tunnel to obtain the tunnel model, use the shell element to simulate the lining structure on the surface of the obtained tunnel model, obtain the lining structure model, and obtain the tunnel lining structure according to the engineering data Physical parameters and assign parameters to the lining structure model, and then perform the initial balance calculation again;
步骤5、在隧道内均匀布设用于获取隧道变形值的分布式光纤/栅传感器，周期性获取每个分布式光纤/栅传感器对应的隧道变形增量实测数据及目标区域对应的总应变εi；Step 5. Distributed optical fiber/grid sensors used to obtain tunnel deformation values are evenly arranged in the tunnel, and the measured data of tunnel deformation increment corresponding to each distributed optical fiber/grating sensor and the total strain εi corresponding to the target area are periodically acquired ;
步骤6、基于步骤4所得三维数值模拟模型确定隧道内目标区域对应围岩的极限应变εm、围岩原岩应力σin、原破坏延伸距离lin；将步骤5中第i次获取的所有隧道变形增量实测数据作为步骤4所得隧道模型内壁的边界条件赋值给步骤4所得三维数值模拟模型，并计算平衡，获取目标区域的应力σi、破坏延伸距离li；Step 6. Based on the three-dimensional numerical simulation model obtained in step 4, determine the ultimate strain εm of the surrounding rock corresponding to the target area in the tunnel, the original rock stress σin of the surrounding rock, and the original failure extension distance lin ; The measured data of tunnel deformation increment is assigned as the boundary condition of the inner wall of the tunnel model obtained in step 4 to the three-dimensional numerical simulation model obtained in step 4, and the balance is calculated to obtain the stress σi and the failure extension distance li of the target area;
步骤7、建立隧道风险等级预警标准：Step 7. Establish tunnel risk level early warning standards:
其中，应力集中系数围岩破坏延伸距离增量系数/>应变速率ΔT为隧道变形增量实测数据的采集周期。Among them, the stress concentration factor Surrounding rock damage extension distance increment coefficient/> Strain rate ΔT is the acquisition period of the tunnel deformation incremental measured data.
本发明的有益效果是：The beneficial effects of the present invention are:
利用光纤传感器获取隧道变形的真实数据后带入隧道的三维数值模型内，进行边界条件的计算，可有效地获取目标区域对应的应变极限等数据，为判断是否存在变形风险提供了高效及准确的判断依据，从而便于根据模拟数据及采集的真实数据进行风险等级的判断，便于后期进行根据风险等级制定相应的应急措施。Using optical fiber sensors to obtain real data of tunnel deformation and bringing them into the 3D numerical model of the tunnel for calculation of boundary conditions can effectively obtain data such as the strain limit corresponding to the target area, providing an efficient and accurate method for judging whether there is a deformation risk Judgment basis, so that it is convenient to judge the risk level based on the simulated data and the real data collected, and it is convenient to formulate corresponding emergency measures according to the risk level in the later stage.
具体实施方式Detailed ways
下面对本发明的实施例作详细说明，本实施例在以本发明技术方案为前提下进行实施，给出了详细的实施方式和具体的操作过程，但本发明的保护范围不限于下述的实施例。The embodiments of the present invention are described in detail below. This embodiment is implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operating procedures are provided, but the protection scope of the present invention is not limited to the following implementation example.
实施例Example
本实施例提供一种融合光纤与模拟技术的隧道全断面变形监测预警方法，该方法在于将光纤监测技术与模拟技术进行融合，从而达到高效且准确的判断隧道内变形风险等级的目的；具体的，该方法包括：This embodiment provides a tunnel full-section deformation monitoring and early warning method that integrates optical fiber and simulation technology. The method is to integrate optical fiber monitoring technology with simulation technology, so as to achieve the purpose of efficiently and accurately judging the deformation risk level in the tunnel; specific , the method includes:
步骤1、收集隧道所在区域地质水文资料及隧道结构资料建立数值模型；Step 1. Collect geological and hydrological data and tunnel structure data in the area where the tunnel is located to establish a numerical model;
即尽可能多的采集隧道所在区域的地质资料、水文资料以及隧道自身的设计资料，建立隧道所在区域对应的数值模型，此时所得数值模型内并未进行隧道的开挖设置，然后进行步骤2。That is to collect as much geological data, hydrological data and tunnel design data as possible in the area where the tunnel is located, and establish a numerical model corresponding to the area where the tunnel is located. At this time, the tunnel excavation setting is not carried out in the obtained numerical model, and then proceed to step 2 .
步骤2、将建立的数值模型网格化后导入FLac3D岩土数值模拟软件建立三维数值模拟模型，所述三维数值模拟模型中：地层强度准则选用摩尔库伦模型，衬砌结构选用壳结构模型；Step 2, gridding the established numerical model into FLac3D geotechnical numerical simulation software to establish a three-dimensional numerical simulation model, in the three-dimensional numerical simulation model: the Mohr Coulomb model is selected as the stratum strength criterion, and the shell structure model is selected for the lining structure;
即将步骤1通过收集数据建立的数值模型根据Flac3D岩土数值模拟软件的要求进行网格化后导入FLac3D岩土数值模拟软件内，形成三维数值模拟模型，此时，在形成的三维数值模拟模型中底层强度地层强度准则选用摩尔库伦模型，衬砌结构选用壳结构模型，建立完成后进行步骤3。That is to say, the numerical model established by collecting data in step 1 is meshed according to the requirements of the Flac3D geotechnical numerical simulation software, and then imported into the FLac3D geotechnical numerical simulation software to form a three-dimensional numerical simulation model. At this time, in the formed three-dimensional numerical simulation model Mohr-Coulomb model is selected as the stratum strength criterion for bottom layer strength, and the shell structure model is selected for the lining structure. After the establishment is completed, proceed to step 3.
步骤3、获取隧道所在区域各地层的岩土体物理学参数并给步骤2所得三维数值模拟模型赋值，取合适的边界条件，进行初始平衡计算；Step 3. Obtain the rock and soil physical parameters of each layer in the area where the tunnel is located and assign values to the three-dimensional numerical simulation model obtained in step 2, and take appropriate boundary conditions to perform initial balance calculations;
即根据FLac3D岩土数值模拟软件内的要求，将隧道所在区域对应各地层的岩土体物理学参数(密度、弹性模量、泊松比、抗拉强度、粘聚力、内摩擦角)获取后导入所得三维数值模拟模型内进行赋值，在软件内选取合适的边界条件后，进行初始平衡的计算，然后进行步骤4。That is, according to the requirements in the FLac3D geotechnical numerical simulation software, the geophysical parameters (density, elastic modulus, Poisson's ratio, tensile strength, cohesion, and internal friction angle) of the tunnel area corresponding to each stratum are obtained. Then import the obtained 3D numerical simulation model for value assignment, select the appropriate boundary conditions in the software, and calculate the initial balance, and then proceed to step 4.
步骤4、根据隧道实际工况对步骤3所得三维数值模拟模型进行隧道模型开挖，得到隧道模型，在所得隧道模型表面利用壳单元模拟衬砌结构，得到衬砌结构模型，根据工程资料获取隧道衬砌结构物理学参数并对衬砌结构模型赋参，然后再次进行初始平衡计算；Step 4. Excavate the tunnel model of the 3D numerical simulation model obtained in step 3 according to the actual working conditions of the tunnel to obtain the tunnel model, use the shell element to simulate the lining structure on the surface of the obtained tunnel model, obtain the lining structure model, and obtain the tunnel lining structure according to the engineering data Physical parameters and assign parameters to the lining structure model, and then perform the initial balance calculation again;
即根据隧道实际的开挖情况(包括其具体尺寸、走向等)在三维数值模拟模型内进行隧道模型的开挖，即建立完整的隧道模型(包括隧道自身及对应的外部地质地形环境)，开挖完成后在所得隧道模型表面利用壳单元模拟衬砌结构，得到衬砌结构模型，根据工程资料获取隧道衬砌结构物理学参数(密度、弹性模量、泊松比、厚度)并对衬砌结构模型赋参，然后再次进行初始平衡计算，即此时隧道及其周边环境完成相应的模拟，建立了完整的隧道模型，之后进行步骤5。That is, according to the actual excavation conditions of the tunnel (including its specific size, direction, etc.), the tunnel model is excavated in the three-dimensional numerical simulation model, that is, a complete tunnel model (including the tunnel itself and the corresponding external geological and topographical environment) is established, and the excavation is carried out. After the excavation is completed, the shell element is used to simulate the lining structure on the surface of the obtained tunnel model to obtain the lining structure model, and the physical parameters (density, elastic modulus, Poisson's ratio, thickness) of the tunnel lining structure are obtained according to the engineering data, and parameters are assigned to the lining structure model. , and then perform the initial balance calculation again, that is, the corresponding simulation of the tunnel and its surrounding environment is completed at this time, and a complete tunnel model is established, and then step 5 is performed.
步骤5、在隧道内均匀布设用于获取隧道变形值的分布式光纤/栅传感器，周期性获取每个分布式光纤/栅传感器对应的隧道变形增量实测数据及目标区域对应的总应变εi；Step 5. Distributed optical fiber/grid sensors used to obtain tunnel deformation values are evenly arranged in the tunnel, and the measured data of tunnel deformation increment corresponding to each distributed optical fiber/grating sensor and the total strain εi corresponding to the target area are periodically acquired ;
即在隧道内均匀布设分布式光纤/栅传感器，用于获取隧道真实的变形值，分布式光纤传感器的布设可在隧道延伸方向上均匀布设，也可在隧道横截面上依次布设，或上述两种方式组合，即保障能够对隧道进行多方位的变形数据采集便可；其次，分布式光栅传感器可在重点区域进行布设，从而进行相应的检测；分布式光纤/栅传感器布设完成后，周期性的进行数据获取，每次获取的数据均与上一次获取的数据进行对比以获取对应的应变变化率，同时也与初始数据进行对比，获取总的应变εi，进而便于后期进行应变模拟，即进行步骤6。That is, distributed optical fiber/grid sensors are evenly arranged in the tunnel to obtain the real deformation value of the tunnel. The distributed optical fiber sensors can be arranged uniformly in the direction of tunnel extension, or sequentially arranged on the cross section of the tunnel, or the above two Combination of two ways, that is, to ensure that the multi-directional deformation data collection of the tunnel is enough; secondly, distributed grating sensors can be deployed in key areas to carry out corresponding detection; after the distributed optical fiber/grating sensors are deployed, periodic Data acquisition is carried out, and the data acquired each time is compared with the data acquired last time to obtain the corresponding strain change rate, and also compared with the initial data to obtain the total strain εi , which is convenient for later strain simulation, namely Go to step 6.
步骤6、基于步骤4所得三维数值模拟模型确定隧道内目标区域对应围岩的极限应变εm、围岩原岩应力σin、原破坏延伸距离lin，即根据所得模型，由模型确定对应的值；将步骤5中第i次获取的所有隧道变形增量实测数据(总应变)作为步骤4所得隧道模型内壁的边界条件赋值给步骤4所得三维数值模拟模型，并计算平衡，获取目标区域的应力σi、破坏延伸距离li，由将所得数据代入模型后获得；Step 6. Based on the three-dimensional numerical simulation model obtained in step 4, determine the ultimate strain εm of the surrounding rock corresponding to the target area in the tunnel, the original rock stress σin of the surrounding rock, and the original failure extension distance lin , that is, according to the obtained model, determine the corresponding value; assign all the measured data (total strain) of the tunnel deformation increment obtained for the ith time in step 5 to the three-dimensional numerical simulation model obtained in step 4 as the boundary condition of the inner wall of the tunnel model obtained in step 4, and calculate the balance to obtain the target area Stress σi and failure extension distance li are obtained by substituting the obtained data into the model;
步骤7、建立隧道风险等级预警标准：Step 7. Establish tunnel risk level early warning standards:
其中，应力集中系数围岩破坏延伸距离增量系数/>应变速率ΔT为隧道变形增量实测数据的采集周期。Among them, the stress concentration factor Surrounding rock damage extension distance increment coefficient/> Strain rate ΔT is the acquisition period of the tunnel deformation incremental measured data.
本方法中，各传感器的供电可由太阳能、市电、预设蓄电池等多种方式进行组合式供电，同时各传感器还与数据收发平台分别连接，数据收发平台与外部设备进行无线数据传输，从而便于远程查看、接收相关数据。In this method, the power supply of each sensor can be combined power supply by various methods such as solar energy, mains power, and preset storage batteries, and at the same time, each sensor is also connected to the data transceiver platform separately, and the data transceiver platform and external equipment perform wireless data transmission, thereby facilitating View and receive relevant data remotely.
以上所述，仅为本发明较佳的具体实施方式，但本发明的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本发明揭露的技术范围内，根据本发明的技术方案及其发明构思加以等同替换或改变，都应涵盖在本发明的保护范围之内。The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, any person familiar with the technical field within the technical scope disclosed in the present invention, according to the technical solution of the present invention Any equivalent replacement or change of the inventive concepts thereof shall fall within the protection scope of the present invention.
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| CN202310427008.5ACN116642426B (en) | 2023-04-17 | 2023-04-17 | A tunnel full-section deformation monitoring and early warning method integrating optical fiber and simulation technology |
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| CN202310427008.5ACN116642426B (en) | 2023-04-17 | 2023-04-17 | A tunnel full-section deformation monitoring and early warning method integrating optical fiber and simulation technology |
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| CN116642426B CN116642426B (en) | 2025-08-05 |
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| CN202310427008.5AActiveCN116642426B (en) | 2023-04-17 | 2023-04-17 | A tunnel full-section deformation monitoring and early warning method integrating optical fiber and simulation technology |
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