The Application of Geological Radar in Forecasting the Adverse Geological in Metamorphic Rock Area Tunnel Construction

2012 ◽  
Vol 531 ◽  
pp. 543-546
Author(s):  
Jiang Tao Xia ◽  
Cheng Zhong Yang ◽  
Shu Fang Wang
Keyword(s):  
Moisture Content ◽  
Metamorphic Rock ◽  
Water Status ◽  
Tunnel Construction ◽  
Construction Process ◽  
Tunnel Face ◽  
Geological Phenomenon ◽  
Zone Water ◽  
Bedding Joint

Accurately surveying out the fault, facture zone, water status and other bad geological phenomenon is the key problems for safety and quality in tunnel construction. Based on the different dielectric electrical differences in characteristics, applying geological radar detected the adverse geological in front of the tunnel face and analyzed. The results show the rock in front of tunnel face is broken, the bedding joint is developed, and there is jointed intensive moisture content with the local rich water. In construction process, the support should be strengthened, excavation method should be adjusted)

Loess Highway Tunnel Construction Process of Three Dimensional Numerical Simulation

2012 ◽  
Vol 256-259 ◽  
pp. 1276-1279
Author(s):  
Bai Liu ◽  
Bin Zhang ◽  
Jing Kong ◽  
Jian Pang
Keyword(s):  
Three Dimensional ◽  
Shanxi Province ◽  
Tunnel Construction ◽  
Western Region ◽  
High Grade ◽  
Construction Process ◽  
Construction Technique ◽  
Loess Area ◽  
Highway Tunnel ◽  
Deformation Law

In recent years, as China's national sustained and rapid economic development, the state increased investment to middle-western region, promote the regional development of high grade highway. Therefore, highway tunnel through loess area is getting more and more. Due to the special physical properties of loess, it makes the loess tunnel construction a hot topic. To study on the deformation law of the loess highway tunnel, this paper based on the Shanxi Province Guang Ling to Hun Yuan highway tunnel—East Fu Yao tunnel, we simulate the whole section pre-reinforcement construction technique for three dimensional numerical, and combined with field monitoring measurement to compare and analyze in paper

Deformation Monitoring and Data Analysis for Metro Construction with Mining Method in Dalian

2013 ◽  
Vol 353-356 ◽  
pp. 1604-1608
Author(s):  
Guang Bin Bai ◽  
Jie Zhao ◽  
Li Sheng Liu
Keyword(s):  
Data Analysis ◽  
Construction Method ◽  
Deformation Monitoring ◽  
Monitoring Data ◽  
Ground Subsidence ◽  
Tunnel Construction ◽  
Mining Method ◽  
Construction Process ◽  
Subway Tunnel ◽  
The Future

Based on a subway tunnel construction, the construction method was introduced. The ground subsidence, crown settlement and convergence displacement caused by the cut tunnel are monitored during the tunneling construction and the results of monitoring data for them are analyzed. This technology wells to guide the tunnel-entering construction effectively and avoid the tunnel-entering construction process prone to landslides, thus ensuring the safety of the tunnel construction and will guiding the future construction.

Research on Water Ecology of Tunnel Engineering in Arid and Semi-Arid Regions

2012 ◽  
Vol 212-213 ◽  
pp. 647-652 ◽  
Author(s):  
Guo Zhen Zhang ◽  
Qian Wang ◽  
Fu Ping Wu
Keyword(s):  
Water Pollution ◽  
Surface Water ◽  
Arid Regions ◽  
Water Environment ◽  
Tunnel Construction ◽  
Construction Process ◽  
Tunnel Engineering ◽  
Surface Water And Groundwater ◽  
Semi Arid ◽  
Water Ecology

This article focuses on the tunnel construction process in arid and semi-arid regions which producing water environment problems ,proposing to initialize the control for the water pollution, containment of surface water and groundwater quality deterioration and loss of water and soil in the process of tunnel construction.The water eco-system of tunnel engineering in the arid and semi-arid regions is researched and established, so as to achieve the control for the surface water and groundwater pollution problems of tunnel project in arid and semi-arid regions, and to provide relevant guidance for the tunnel project.

De-coupling seasonal changes in water content and dry matter to predict live conifer foliar moisture content

2014 ◽  
Vol 23 (4) ◽  
pp. 480 ◽  
Author(s):  
W. Matt Jolly ◽  
Ann M. Hadlow ◽  
Kathleen Huguet
Keyword(s):  
Water Stress ◽  
Moisture Content ◽  
Water Content ◽  
Seasonal Variations ◽  
Seasonal Changes ◽  
Dry Matter ◽  
Water Mass ◽  
Water Status ◽  
Dry Mass ◽  
Dry Matter Partitioning

Live foliar moisture content (LFMC) significantly influences wildland fire behaviour. However, characterising variations in LFMC is difficult because both foliar mass and dry mass can change throughout the season. Here we quantify the seasonal changes in both plant water status and dry matter partitioning. We collected new and old foliar samples from Pinus contorta for two growing seasons and quantified their LFMC, relative water content (RWC) and dry matter chemistry. LFMC quantifies the amount of water per unit fuel dry weight whereas RWC quantifies the amount of water in the fuel relative to how much water the fuel can hold at saturation. RWC is generally a better indicator of water stress than is LFMC. We separated water mass from dry mass for each sample and we attempted to best explain the seasonal variations in each using our measured physiochemical variables. We found that RWC explained 59% of variation in foliar water mass. Additionally, foliar starch, sugar and crude fat content explained 87% of the variation in seasonal dry mass changes. These two models combined explained 85% of the seasonal variations in LFMC. These results demonstrate that changes to dry matter exert a stronger control on seasonal LFMC dynamics than actual changes in water content, and they challenge the assumption that LFMC variations are strongly related to water stress. This methodology could be applied across a range of plant functional types to better understand the factors that drive seasonal changes in LFMC and live fuel flammability.

3D-FEM Stability Analysis of Fault Fractured Zone of Road Tunnel

2011 ◽  
Vol 413 ◽  
pp. 166-169 ◽  
Author(s):  
Jin Xing Lai ◽  
Chi Liu ◽  
Fei Zhou
Keyword(s):  
Finite Element ◽  
Fracture Zone ◽  
Three Dimensional ◽  
Tunnel Construction ◽  
Construction Process ◽  
Road Tunnel ◽  
3D Fem ◽  
Fault Fracture Zone ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

In order to analyze the stability of the tunnel construction of the fault fracture zone, by adopting the three-dimensional finite element, the paper analyzed the construction process of the Qingshashan Tunnel passing through the F5 fault fracture zone, and the rules and characteristics of deformation, stress distribution and its rules of changes, and the distribution range of the failure zone of the surrounding rock in the construction process, which would have important significance in guiding tunnel construction. Studies have shown that the three-dimensional finite element has a broad application prospect in tunnel projects.

Imaging the Geology Ahead of a Tunnel Using Seismics and Adaptive Polarization Analysis

2020 ◽  
Vol 25 (2) ◽  
pp. 189-198
Author(s):  
Lei Chen ◽  
Chao Fu ◽  
Xinji Xu ◽  
Lichao Nie
Keyword(s):  
Time Window ◽  
Geophysical Methods ◽  
Weighting Coefficient ◽  
Tunnel Construction ◽  
Polarization Analysis ◽  
Polarization Direction ◽  
Tunnel Face ◽  
Seismic Method ◽  
Imaging Results ◽  
Geological Conditions

The seismic method is one of the main geophysical methods that are widely used to image the geology ahead of tunnels during tunnel construction. However, owing to the complex environment and limited observation aperture in a tunnel, symmetric false results (that appear in imaging results but not in the actual environment) frequently occur in imaging results. In a symmetric false reflection, false and true reflection points are axisymmetric around the tunnel axis. Such false results frequently cause errors in the interpretation of the geological conditions ahead of a tunnel face. To overcome this problem, a seismic method that uses adaptive polarization analysis was adopted to better image geological conditions. Based on an adaptive time window, the polarization characteristics of seismic signals were analyzed to calculate the main polarization direction. The symmetric false results in imaging results were suppressed by adopting a weighting coefficient based on the angle between the main polarization direction and ray direction. Numerical simulations revealed the superiority of the method when applied to synthetic data processing. Moreover, the method was applied to a diversion tunnel. The method successfully identified the fracture zones ahead of the tunnel face, thus significantly enhancing the safety of tunnel construction.

scholarly journals Stability Analysis of Shallow and Bias Loess Tunnel Based on Finite Difference Method

2019 ◽  
Vol 131 ◽  
pp. 01027
Author(s):  
Li Yongbing ◽  
Binglei Li ◽  
Guanyu Hua ◽  
Xinran Jia ◽  
Yanqiao Chen ◽  
...  
Keyword(s):  
Finite Difference ◽  
Shear Failure ◽  
Surrounding Rock ◽  
Tunnel Construction ◽  
Failure Zone ◽  
Tunnel Face ◽  
Whole Process ◽  
The Earth ◽  
Practical Engineering ◽  
The Stability

Based on the Mohr-Coulomb elastic-plastic model and the practical engineering background of Mopanshan tunnel, this paper applies the finite-difference software FLAC3D to simulate and analyse the whole process of loess tunnel construction. Then, it analyses the stability of the surrounding rock and sup-port structure after partial excavation of the loess tunnel under the shallow burying and unsymmetrical load-ing condition. The study showed that in the absence of support, the shear failure occurred to the top/upper pilot tunnel of the tunnel face, the failure zone under tensile stress happened to the shallow soil of the earth surface, and the soil of tunnel face appeared to be damaged. Finally, according to the analysis results, a rea-sonable construction method suitable for the shallow and bias loess tunnel is determined.

Application of the Improved Analytic Hierarchy Process in the Risk Management of Tunnel Construction

2014 ◽  
Vol 696 ◽  
pp. 295-300 ◽  
Author(s):  
Xue Xian Chen ◽  
Rong Huai Chen ◽  
Kui Lin ◽  
Ming Wei Zhang
Keyword(s):  
Risk Assessment ◽  
Analytic Hierarchy Process ◽  
Evaluation Index System ◽  
Evaluation Index ◽  
Tunnel Construction ◽  
Investment Risk ◽  
Construction Process ◽  
Analytic Hierarchy ◽  
Hierarchy Process ◽  
Improved Analytic Hierarchy Process

As the tunnel project has the characteristics of concealment, complexity, uncertainty and the larger investment risk, whose insidious danger is outstanding especially in the construction process. It is important for the safety of the construction process to determine the potential risk and minimize the risk using reasonable methods. Based on the experts investigation, 3-hierarchy and eighteen factors’ evaluation index system of risk assessment is established through the improved analytic hierarchy process. The results show that this method is reasonable and can greatly reduce graded difficulties.

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