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Full-Text Articles in Structural Materials
A Method For Determining Integrity Degree Of Tunnel Surrounding Rock Based On Mobilenet, Liu Houxiang, Yang Caixia
A Method For Determining Integrity Degree Of Tunnel Surrounding Rock Based On Mobilenet, Liu Houxiang, Yang Caixia
Journal of China & Foreign Highway
To determine the integrity degree of tunnel surrounding rock more efficiently,a precise determination method for the integrity degree of tunnel surrounding rock based on the lightweight neural network MobileNet-v 2 was proposed.Firstly,the image was grayscaled and denoised,and the edges of cracks were detected.Then,the lightweight neural network MobileNet-v 2 model was pre-trained on the ImageNet dataset,and combined with transfer learning to complete data detection on the training,validation,and testing sets.Finally,a comparative experiment was conducted with traditional neural networks RestNet- 50 and VGG 16.By identifying the area,width,and length of cracks,the crack ratio Ks was introduced as an indicator to evaluate the integrity of …
Quantitative Evaluation Of Tunnel Rock Mass Integrity Based On Mwd Technology, Zhang Kunmu, Peng Hao, Liang Ming, Han Yu, Song Guanxian
Quantitative Evaluation Of Tunnel Rock Mass Integrity Based On Mwd Technology, Zhang Kunmu, Peng Hao, Liang Ming, Han Yu, Song Guanxian
Journal of China & Foreign Highway
In tunnel construction,the quantitative evaluation of rock mass integrity heavily relies on information from the exposed face,and there are challenges when drilling data is used for integrity evaluation.To this end,this study introduced a novel method for quantitative evaluation of rock mass integrity during drilling,integrating numerical statistics with machine learning.A substantial dataset of digital drilling data was collected,covering three common types of rock mass integrity:relatively intact,relatively fractured,and fractured.Subsequently,a high-performance random forest model for the classification of rock mass integrity was developed through data preprocessing and hyperparameter optimization.The interpretability of the model ’s predictive results was enhanced using Shapley additive explanations (SHAP …
Research On Mechanical Entry Excavation And Reinforcement Measures For Large Cross-Section Tunnel, Liang Xiao, Li Ke, Guo Hongyan, Hu Xuebing, Yao Chengrui
Research On Mechanical Entry Excavation And Reinforcement Measures For Large Cross-Section Tunnel, Liang Xiao, Li Ke, Guo Hongyan, Hu Xuebing, Yao Chengrui
Journal of China & Foreign Highway
With the innovation of tunnel construction techniques and mechanical equipment,mechanical drilling and blasting for mountain tunnels have gradually developed.However,several challenges exist during the mechanical entry excavation for mountain tunnels,including the significant influence of geological factors,limited equipment adaptability,and constrained working space.This research,based on a specific tunnel project,utilized FLAC3D finite difference software to study the mechanical excavation method and auxiliary reinforcement measures for shallow-buried segments at the large cross-section tunnel portal.A comparative analysis was conducted on the displacement of surrounding rock,the stress of supporting structures,and the variation of plastic zones before and after tunnel face reinforcement for different advances per cycle and …
Comparative Study Of Different Ventilation Methods During Tunnel Construction, Yue Kun, Bao Xiaohua, Ao Xiang, Liu Kuan, Wu Han, Li Tao, Shen Jun
Comparative Study Of Different Ventilation Methods During Tunnel Construction, Yue Kun, Bao Xiaohua, Ao Xiang, Liu Kuan, Wu Han, Li Tao, Shen Jun
Journal of China & Foreign Highway
The continuous improvement of tunnel construction technology brings a rapid increase in the speed and mileage of tunnel excavation，during which ventilation is a main problem affecting construction efficiency and safety.Taking the Zhuhai Xingye Express （West Line ） tunnel project as an example，this paper studied the influences of forced ventilation，exhaust ventilation，and hybrid ventilation on the dilution and discharge of harmful gas CO near the tunnel face and the wind speed in the tunnel.The results show that hybrid ventilation performs better in CO dilution，while exhaust ventilation has higher CO emission efficiency with a lower wind speed near the working face.Therefore，although forced ventilation …
Fume Emission And Environmental Impact Assessment In Fresh Asphalt Tunnel Construction Site, Deng Wenti, Zou Guilian, Zhang Yuan, Yu Liang, Xie Huiduan
Fume Emission And Environmental Impact Assessment In Fresh Asphalt Tunnel Construction Site, Deng Wenti, Zou Guilian, Zhang Yuan, Yu Liang, Xie Huiduan
Journal of China & Foreign Highway
In view of the random monitori ng of fum e emission in asphalt pavement construction sites，combined with the engineering application of fresh asphalt in the construction of hot-mixed and hot-spread asphalt pavement in large and long tunnels for fume emission reduction，the fume collection and evaluation method of asphalt pavement construction sites were studied，and the emission reduction effect of fresh asphalt was evaluated.The Summa tanks were used to collect the asphalt fume at different positions of the paver，and the asphalt fume was quantitatively analyzed by gas chromatograph-mass spectrometer （GC-MS）.The results show that compared with the non-fresh asphalt from the same source，the …
Calculation Analysis Of The S Urrounding Rock Pressure In Shallow Buried Unsymmetrial Tunnel Under Variable Slope, Bai Yan, Qiao Ting Ting, Ning Xiaojun, Liu Guokun
Calculation Analysis Of The S Urrounding Rock Pressure In Shallow Buried Unsymmetrial Tunnel Under Variable Slope, Bai Yan, Qiao Ting Ting, Ning Xiaojun, Liu Guokun
Journal of China & Foreign Highway
To provide a reasonable meth od for calculating the surrounding rock pressure in shallow buried unsymmetrial pressure tunnels under variable slope conditions for tunnel design,to establish a model for calculating the surrounding rock pressure in shallow buried unsymmetrial pressure tunnels under variable slope conditions,and to employ the principle of ultimate equilibrium to derived the formula for calculating the surrounding rock pressure.The intermediate variable β' is introduced as the base for selecting the unsymmetrial pressure tunnels surrounding rock pressure calculation method under variable slope conditions,and the derived formulas in this paper are verified by comparing the calculated values of the normative …
Dynamic Response Rules Of Adjacent Buildings To Blasting Construction In Shallow Buried Tunnels, Luo Yanping, Li Jigang, Wang Sheng, Zeng Bin, Lai Jinxing, Feng Zhihua, Qiu Junling
Dynamic Response Rules Of Adjacent Buildings To Blasting Construction In Shallow Buried Tunnels, Luo Yanping, Li Jigang, Wang Sheng, Zeng Bin, Lai Jinxing, Feng Zhihua, Qiu Junling
Journal of China & Foreign Highway
In order to study the dynamic response rule of overlying buildings during blasting construction in shallow buried tunnels,the urban tunnel in Fuzhou was taken as the engineering background,and the on-site monitoring and Ansys/LS-DYNA simulation were used to analyze the structural response of overlying buildings.The monitoring results show that the building is most obviously affected by blasting in the vertical direction and has an obvious elevation amplification effect,and the maximum vibration velocity is 2.45 cm/s.The vibration velocity in all directions gradually decreases and tends to be stable with the increase in explosion center distance and decays rapidly when the explosion center …
Reasonable Construction Method For Grade Ⅳ Surrounding Rock In Single‑Hole Four‑Lane Super‑Span Highway Tunnel, Li Heyin, Gao Jingming, Li Yanfeng, Xun Wenjie, Dong Fangfang, Zhang Jiangang
Reasonable Construction Method For Grade Ⅳ Surrounding Rock In Single‑Hole Four‑Lane Super‑Span Highway Tunnel, Li Heyin, Gao Jingming, Li Yanfeng, Xun Wenjie, Dong Fangfang, Zhang Jiangang
Journal of China & Foreign Highway
In order to study the reasonable constr uction method of super-span highway tunnels，the Xinghuacun No.1 tunnel included in the reconstruction and expansion project of the Xiaocaohu –Urumqi section of the Lianyungang –Khorgos Expressway in Xinjiang was studied.The numerical simulation method was used to analyze the deformation and stress of the supporting structure of the Grade tisurrounding rock in the super-span highway tunnel constructed by the center diaphragm （CD） method，the upper-bench CD method，and the three-bench and seven-step excavation method.Under the premise that the deformation and the stress of the supporting structure met the design requirements，the advantages and disadvantages of each construction …
Test On Water Mist Wrapped Dust Reduction Technology For Tunnels, Wang Yijun, Wang Fei, Jia Yuedi, Pan Weihua, He Xingchun, Yao Wenhui
Test On Water Mist Wrapped Dust Reduction Technology For Tunnels, Wang Yijun, Wang Fei, Jia Yuedi, Pan Weihua, He Xingchun, Yao Wenhui
Journal of China & Foreign Highway
In order to eliminate the dust produced by tunnel blasting more quickly and effectively，two kinds of mist spray and dust reduction schemes were put forward，which were the “air duct water mist wrapped type ” and the “vehicle-mounted water mist wrapped type ”.The field test was carried out on Jiaoding Tunnel in Yunnan.The results show that for the dust reduction technology scheme of “air duct water mist wrapped type ”，the dust concentration of the No.1 characteristic position at the tunnel face decreases to 3.87 mg/m3 after 10 minutes of dust reduction，which meets the specification requirements.For the dust reduction technology of “vehicle-mounted …
Risk Assessment Calculation Of Layered Surrounding Rock Tunnel Based On Combination Weight-Eahp-Ncm Model Theory, Yang Yongbin, Wang Qing, Wang Yijun, Gao Weizheng, Li Yongliang
Risk Assessment Calculation Of Layered Surrounding Rock Tunnel Based On Combination Weight-Eahp-Ncm Model Theory, Yang Yongbin, Wang Qing, Wang Yijun, Gao Weizheng, Li Yongliang
Journal of China & Foreign Highway
To accurately assess and calculate the structural stability of layered surrounding rock tunnels during construction, this paper firstly constructed a risk assessment index system for layered surrounding rock tunnels based on the consideration of factors of hydrogeology, structural surfaces, engineering, external forces, and topography and geomorphology. Based on the Delphi method (DELPHI) and entropy weight method (EWM), the combination of indicators was assigned. Based on the typical event samples and the mining of classical domains-joint domains of the assessment system, the extension analytic hierarchy process calculation model (EAHP) and normal cloud computing model (NCM) were built to assess the stability …
Study On Supporting Effect Of Pre‐Stressed Rock Bolts On Tunnel Face, Shen Xiangqian, Chen Daoyun, Zheng Chao
Study On Supporting Effect Of Pre‐Stressed Rock Bolts On Tunnel Face, Shen Xiangqian, Chen Daoyun, Zheng Chao
Journal of China & Foreign Highway
Focusing on the stability issues of the tunnel face in the large deformation section of soft rock in the Muzhailing Tunnel on the Weiyuan-Wudu Expressway, this paper proposes a technical solution for temporary reinforcement of the tunnel face using pre-stressed rock bolts. Numerical simulations were conducted to evaluate the reinforcement effect and effective range of pre-stressed rock bolts on the tunnel face, and the influence of initial ground stress on the reinforcement effect was further analyzed. The results show that under the given engineering conditions, pre-stressed rock bolts demonstrate significantly better reinforcement effects on the tunnel face compared to fully …
Study On Parameter Optimization Of Feet‐Lock Anchor Pipes Of Tunnels In Unconsolidated Formation, Tang Heqing, Jiang Xishan, Yang Peng
Study On Parameter Optimization Of Feet‐Lock Anchor Pipes Of Tunnels In Unconsolidated Formation, Tang Heqing, Jiang Xishan, Yang Peng
Journal of China & Foreign Highway
In order to give full play to the supporting role of the feet-lock anchor pipe in the tunnel with unconsolidated formation, it is necessary to obtain the optimal construction parameters of the feet-lock anchor pipe. Based on a tunnel project on the Huaping–Lijiang Expressway in Yunnan Province, this paper conducted numerical simulation and field test analysis. By comparing the arch subsidence and horizontal convergence of the supporting structure when the feet-lock anchor pipe with different parameters was constructed, the paper explored the characteristics and causes of the influence of construction parameters on the feet-lock effect. The results show that the …
Study On Parameter Optimization Of Feet‐Lock Anchor Pipes Of Tunnels In Unconsolidated Formation, Tang Heqing, Jiang Xishan, Yang Peng
Study On Parameter Optimization Of Feet‐Lock Anchor Pipes Of Tunnels In Unconsolidated Formation, Tang Heqing, Jiang Xishan, Yang Peng
Journal of China & Foreign Highway
In order to give full play to the supporting role of the feet-lock anchor pipe in the tunnel with unconsolidated formation, it is necessary to obtain the optimal construction parameters of the feet-lock anchor pipe. Based on a tunnel project on the Huaping–Lijiang Expressway in Yunnan Province, this paper conducted numerical simulation and field test analysis. By comparing the arch subsidence and horizontal convergence of the supporting structure when the feet-lock anchor pipe with different parameters was constructed, the paper explored the characteristics and causes of the influence of construction parameters on the feet-lock effect. The results show that the …