Analysis of Warning Threshold of Tunnel Monitoring and Measurement Based on Probability Statistics

In the process of tunnel construction, data on deformation monitoring magnifies the direct reflection of the stability of tunnel structure, and the setting of early warning value is more related to the safety of project construction. In this paper, a tunnel project is taken as an example, and based on a large number of previous engineering practices and the statistical characteristics of monitoring data, the probability statistics method is used to obtain the warning threshold, which is used to give suggestions for the construction of the tunnel project and provide technical reference for the monitoring and warning management of similar tunnel construction.

Enhancing Railway Maintenance Safety Using Open-Source Computer Vision

As high-speed railways continue to be constructed, more maintenance work is needed to ensure smooth operation. However, this leads to frequent accidents involving maintenance workers at the tracks. Although the number of such accidents is decreasing, there is an increase in the number of casualties. When a maintenance worker is hit by a train, it invariably results in a fatality; this is a serious social issue. To address this problem, this study utilized the tunnel monitoring system installed on trains to prevent railway accidents. This was achieved by using a system that uses image data from the tunnel monitoring system to recognize railway signs and railway tracks and detect maintenance workers on the tracks. Images of railway signs, tracks, and maintenance workers on the tracks were recorded through image data. The Computer Vision OpenCV library was utilized to extract the image data. A recognition and detection algorithm for railway signs, tracks, and maintenance workers was constructed to improve the accuracy of the developed prevention system.

Optimal Sensor Placement for Underground Tunnel Monitoring via Wireless Sensor Networks

In replace of human labor, wireless sensor networks (WSNs) are increasingly being utilized to perform structural health monitoring of underground tunnel. Due to its complex environment, the deployment of sensor nodes poses a big challenge to related staff. How to use the optimal number of sensor nodes deployed in the underground tunnel to obtain a satisfactory monitoring is our main consideration. In this paper, we propose a deployment strategy based on the optimal index to provide guidelines for sensor node placement. The objective of the strategy is to put sensor nodes in a proper site to gain maximum sensing information, thus eliminating redundant sensor nodes as well as saving costs.

Advantages of tunnel monitoring using distributed fibre optic sensing

Predictive maintenance and safety assessment during the construction and operational phase are becoming more and more important in modern tunnelling. However, traditional measurement methods are often time-consuming, expensive and partially require an interruption of the tunnel traffic. In this article, we present a tunnel monitoring approach based on distributed fibre optic sensing (DFOS), which delivers hundreds of strain and temperature sensing points inside the structure and gives completely new information about the behaviour of the tunnel lining. Measurements can be performed automatically without the need of access to the tunnel and hence, monitoring can be made without disturbing the tunnel construction or operation. The developed system was installed within the shotcrete tunnel lining of a railway tunnel under construction in Austria. In addition to the critical installation process, this article discusses the main monitoring results and compares them to conventional measurements.

The application of black-box modeling in long-term tunnel deformation monitoring

<p>Tunnel closures related to maintenance and reconstruction works can lead to large economical costs and should therefore be avoided. This paper explores the use of novelty detection algorithms for long-term tunnel monitoring. The aim is to detect tunnel damage in an early stage, as such providing a tool to support the asset management. The proposed strategy is applied to the monitoring of the Waasland tunnel in Antwerp, where the deformations and temperatures have been monitored over a period of 14 months. The case demonstrates that novelty detection by means of principal component analysis enables the identification of minor changes in the tunnel response, and can therefore be embedded in an early detection warning system.</p>

Engineering application and study on polyurethane-corrugated steel plate insulation lining of existing railway tunnel in seasonal frozen area

In order to solve the problem of freezing damage treatment and anti-freezing design for railway tunnels in operation in the seasonal frozen area, this paper proposes a polyurethane-corrugated steel plate insulation lining, and studies its thermal insulation effect, relying on a freezing damage treatment project of an existing passenger-dedicated tunnel for on-site application. In this paper, the insulation lining is applied to the actual project and the insulation effect is verified by the field monitoring. The temperature test section was set in the anti-freezing design section. The polyurethane-corrugated steel plate insulation lining proposed in this paper is mainly composed of corrugated steel plate, polyurethane insulation layer and waterproof layer. The polyurethane-corrugated steel insulation lining is applied by using self-made rail flat battery car, door-type scaffolding, arch slide and other construction equipments. The on-site temperature test shows that the insulation effect is obvious. The polyurethane-corrugated steel plate insulation lining has the advantages of fast construction speed, good thermal insulation effect, preventing concrete from peeling off blocks, easy removal and replacement. According to the field temperature test, under the natural temperature outside the tunnel from −18°C to −22°C in winter of 2018–2020, the temperature of the interface between surrounding rock and lining of the tunnel monitoring sections are all above 0°C so that the freezing damage is eliminated from the root. Research results can provide a theoretical basis for the anti-freezing projects of tunnels in seasonal frozen area.

Optimization Analysis of Smart Steel-Plastic Geogrid Support for Tunnel

With the concept of smart geogrid coming out, many scholars have built optical fiber into the geogrid to form a kind of smart geogrid material with self-sensing function of structural deformation. It can not only reinforce the parts with potential safety hazards, but also have the functions of safety monitoring, intelligent prevention, and control of engineering disasters, which is of great significance for ensuring the safety of tunnel construction and improving the tunnel monitoring methods. Based on predecessors’ research on smart geogrid tensile calibration experiment and sensor method simulation and experimental verification, this paper analyzes the smart geogrid and the tunnel surrounding rock as a whole, to study the deformation coordination mechanism between the geogrid material and the tunnel surrounding rock. Referring to the relevant engineering practice case, through finite element numerical simulation, the optimal layout of smart geogrid material was explored, and the principle of discrete curvature reconstruction curve sensing of smart geogrid was optimized by simulating the working conditions of different construction methods and supporting conditions, in order to provide a theoretical basis for the application of smart geogrid material in practical tunnel engineering.

Design and Implement of Cable Tunnel Monitoring System based on Environmental Engineering

At present, the quick advancement of intensity flexibly has carried incredible difficulties to the protected activity of the link and the counteraction of mishaps in power transmission. In any case, utilizing customary manual strategies to keep up the link doesn't satisfy the current need. Accordingly, dealing with the activity of the links by means of cutting edge PC innovation is critical for the force transmission. In this paper, we build up a natural designing based observing framework for link passage to give the ongoing checking just as the mishap taking care of for link activity. It is another answer for the administration of links activity. The paper breaks down the structure of the framework, expounds on the execute, shows the use of the framework lastly makes the end.