Tunnelling and Underground Space Technology最新文献_第2页

Effect of soil improvement on ground movements induced by conventional tunnelling 土壤改良对传统隧道开挖引起的地面移动的影响

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-11-01 DOI: 10.1016/j.tust.2024.106163

Line C of Rome underground will cross the city from southeast to northwest, with a total length of about 25 km, passing through the historical city centre. This is a difficult environment due to many archaeological finds and pre-existing buildings of great historical value. Along stretch T3 of the line two conventional tunnels connect the TBMs launching pit to the new San Giovanni station. They run for a length of 140 m at a depth of about 25 m and reach the station passing at a short distance from the ancient Aurelian Walls (3rd century CE). Excavation of these tunnels was carried out following a three-stage procedure: (i) excavation of two small diameter tunnels (D = 3 m) using a mini slurry shield machine; (ii) soil improvement via cement grouting using tubes à manchettes installed radially from the mini-tunnels; and (iii) conventional excavation of the two running tunnels in the improved soil. An extensive monitoring system was set to control ground movements induced throughout the excavation process.

This paper presents the displacement measured at the ground surface during the construction activities, highlighting the effects induced by grouting. The effectiveness of a protective barrier, made by a line of piles, in reducing the movements induced by tunnelling in the Aurelian Walls is also assessed. A 2D FE back-analysis is finally presented, showing that a satisfactory description of the observed behaviour can only be obtained by simulating the volume changes induced by the cement grouting.

罗马地铁 C 号线将从东南向西北穿越城市，全长约 25 公里，途经历史悠久的市中心。由于这里有许多考古发现和具有重要历史价值的原有建筑，施工环境十分艰苦。在 T3 号线沿线，有两条传统隧道将掘进机发射井与新的圣乔瓦尼车站连接起来。隧道全长 140 米，深约 25 米，到达车站时与古代奥雷利安城墙（公元 3 世纪）相距不远。这些隧道的挖掘工作分三个阶段进行：(i) 使用小型泥浆盾构机挖掘两条直径较小的隧道（D = 3 米）；(ii) 使用从小型隧道径向安装的管子 à 弯管，通过水泥灌浆改良土壤；(iii) 在改良土壤中对两条隧道进行常规挖掘。本文介绍了施工过程中在地表测量到的位移，突出了灌浆的影响。本文还评估了由一排桩构成的保护屏障在减少奥雷利安墙隧道挖掘引起的位移方面的有效性。最后介绍了二维 FE 反向分析，结果表明，只有通过模拟水泥灌浆引起的体积变化，才能令人满意地描述观察到的行为。

{"title":"Effect of soil improvement on ground movements induced by conventional tunnelling","authors":"","doi":"10.1016/j.tust.2024.106163","DOIUrl":"10.1016/j.tust.2024.106163","url":null,"abstract":"<div><div>Line C of Rome underground will cross the city from southeast to northwest, with a total length of about 25 km, passing through the historical city centre. This is a difficult environment due to many archaeological finds and pre-existing buildings of great historical value. Along stretch T3 of the line two conventional tunnels connect the TBMs launching pit to the new San Giovanni station. They run for a length of 140 m at a depth of about 25 m and reach the station passing at a short distance from the ancient Aurelian Walls (3rd century CE). Excavation of these tunnels was carried out following a three-stage procedure: (<em>i</em>) excavation of two small diameter tunnels (<em>D</em> = 3 m) using a mini slurry shield machine; (<em>ii</em>) soil improvement via cement grouting using <em>tubes à manchettes</em> installed radially from the mini-tunnels; and (<em>iii</em>) conventional excavation of the two running tunnels in the improved soil. An extensive monitoring system was set to control ground movements induced throughout the excavation process.</div><div>This paper presents the displacement measured at the ground surface during the construction activities, highlighting the effects induced by grouting. The effectiveness of a protective barrier, made by a line of piles, in reducing the movements induced by tunnelling in the Aurelian Walls is also assessed. A 2D FE back-analysis is finally presented, showing that a satisfactory description of the observed behaviour can only be obtained by simulating the volume changes induced by the cement grouting.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on working mechanism and mechanical properties of retractable U-shaped steel gangue prevention structure 可伸缩 U 形钢防矸结构的工作机理和力学性能研究

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-10-31 DOI: 10.1016/j.tust.2024.106167

In the process of the gob-side roadway retaining by roof cutting, the retractable U-shaped steel (RUSS) has a broad application prospect in the stability control of gangue rib. In order to establish RUSS support design method, the working mechanism and mechanical properties of RUSS are studied by using theoretical analysis, numerical experiment and field test. The research results show that RUSS will be subjected to multiple loads of roof deformation, gangue impact and lateral pressure of gangue rib during service; The failure of RUSS is a gradual process, the lateral pressure of gangue rib is identified as the key factor leading to failure of RUSS; The mechanical properties of RUSS can be effectively improved by increasing the overlap ratio and section size. Under the same impact energy, the peak impact force of U36 steel is 17.9% and 29.9% higher compared to U29 and U25, respectively. When the overlap ratio increases from 0.45 to 0.6, the instability critical load of RUSS increases by 32.4% and the deformation decreases by 31.1%; Finally, according to the results of theoretical analysis and numerical experiments, a standardized design method of RUSS is proposed, and applied on the S1201 working face of the Ningtiaota Coal Mine. The field monitoring data show that the design scheme of RUSS is rational.

在切顶挡矸巷道过程中，可伸缩U型钢（RUSS）在矸石筋稳定性控制方面具有广阔的应用前景。为了建立 RUSS 支护设计方法，通过理论分析、数值实验和现场试验，对 RUSS 的工作机理和力学性能进行了研究。研究结果表明，RUSS 在使用过程中会受到顶板变形、矸石冲击和矸石肋侧压力等多重载荷的作用；RUSS 的失效是一个渐进的过程，矸石肋侧压力被认为是导致 RUSS 失效的关键因素；通过增大重叠率和截面尺寸可以有效改善 RUSS 的力学性能。在相同冲击能量下，U36 钢的峰值冲击力分别比 U29 和 U25 高出 17.9% 和 29.9%。当重叠率从 0.45 增加到 0.6 时，RUSS 的失稳临界载荷增加了 32.4%，变形减少了 31.1%；最后，根据理论分析和数值实验结果，提出了 RUSS 的标准化设计方法，并将其应用于宁铁塔煤矿 S1201 工作面。现场监测数据表明，RUSS 的设计方案是合理的。

{"title":"Study on working mechanism and mechanical properties of retractable U-shaped steel gangue prevention structure","authors":"","doi":"10.1016/j.tust.2024.106167","DOIUrl":"10.1016/j.tust.2024.106167","url":null,"abstract":"<div><div>In the process of the gob-side roadway retaining by roof cutting, the retractable U-shaped steel (RUSS) has a broad application prospect in the stability control of gangue rib. In order to establish RUSS support design method, the working mechanism and mechanical properties of RUSS are studied by using theoretical analysis, numerical experiment and field test. The research results show that RUSS will be subjected to multiple loads of roof deformation, gangue impact and lateral pressure of gangue rib during service; The failure of RUSS is a gradual process, the lateral pressure of gangue rib is identified as the key factor leading to failure of RUSS; The mechanical properties of RUSS can be effectively improved by increasing the overlap ratio and section size. Under the same impact energy, the peak impact force of U36 steel is 17.9% and 29.9% higher compared to U29 and U25, respectively. When the overlap ratio increases from 0.45 to 0.6, the instability critical load of RUSS increases by 32.4% and the deformation decreases by 31.1%; Finally, according to the results of theoretical analysis and numerical experiments, a standardized design method of RUSS is proposed, and applied on the S1201 working face of the Ningtiaota Coal Mine. The field monitoring data show that the design scheme of RUSS is rational.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Safety evaluation of in-service sulfate corrosion tunnel considering time effect and free surface evaporation effect 考虑时间效应和自由表面蒸发效应的在役硫酸盐腐蚀隧道安全评估

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-10-31 DOI: 10.1016/j.tust.2024.106165

The safety evaluation of tunnel linings after a sulfate attack is an important basis for ensuring the safety of tunnel service time. However, the existing tunnel safety evaluation methods are not specific enough regarding the service time, and the corresponding sulfate corrosion indoor test that does not consider the single-sided corrosion factor. Therefore, in order to evaluate the disease characteristics of the tunnel lining after sulfate attack, a lining safety evaluation method has been proposed with considering the time effect and free surface evaporation effect based on the micro-element-layering method. The key parameters of the safety evaluation model were solved through 420 days of indoor corrosion tests and numerical simulations. Moreover, compared with the test results, the variation law of the lining safety coefficient in the position of the arch foot corrosion and arch foot-waist corrosion was further studied. The results show that: the evaporation sulfate corrosion model of the free surface can accurately reveal the strength degradation mechanism of the tunnel lining, in addition to the temporal and spatial evolution law of the sulfate ions. Moreover, the prediction results of effective strength in the process of safety evaluation were in good agreement with the experimental results. In the stage of tunnel lining corrosion, the decrease in the safety factor of the arch foot corrosion and arch foot-waist corrosion section was slow and then fast within the operation time. The service life of the tunnel depends on the corrosion of the most dangerous parts. The increase in the corrosion area will not reduce the service life of the tunnel.

隧道衬砌遭受硫酸盐侵蚀后的安全评价是确保隧道服役时间安全的重要依据。然而，现有的隧道安全评价方法对服役时间的规定不够具体，相应的硫酸盐腐蚀室内试验也未考虑单侧腐蚀因素。因此，为了评价隧道衬砌在硫酸盐侵蚀后的病害特征，提出了一种基于微元素分层法的考虑时间效应和自由表面蒸发效应的衬砌安全评价方法。通过 420 天的室内腐蚀试验和数值模拟，求解了安全评价模型的关键参数。此外，与试验结果相比，还进一步研究了衬里安全系数在拱脚腐蚀和拱脚腰腐蚀位置上的变化规律。结果表明：自由表面蒸发硫酸盐腐蚀模型能准确揭示隧道衬砌的强度退化机理，以及硫酸根离子的时空演化规律。此外，安全评价过程中的有效强度预测结果与实验结果吻合良好。在隧道衬砌腐蚀阶段，拱脚腐蚀段和拱脚腰腐蚀段的安全系数在运营时间内的下降速度先慢后快。隧道的使用寿命取决于最危险部位的腐蚀情况。腐蚀面积的增加不会降低隧道的使用寿命。

{"title":"Safety evaluation of in-service sulfate corrosion tunnel considering time effect and free surface evaporation effect","authors":"","doi":"10.1016/j.tust.2024.106165","DOIUrl":"10.1016/j.tust.2024.106165","url":null,"abstract":"<div><div>The safety evaluation of tunnel linings after a sulfate attack is an important basis for ensuring the safety of tunnel service time. However, the existing tunnel safety evaluation methods are not specific enough regarding the service time, and the corresponding sulfate corrosion indoor test that does not consider the single-sided corrosion factor. Therefore, in order to evaluate the disease characteristics of the tunnel lining after sulfate attack, a lining safety evaluation method has been proposed with considering the time effect and free surface evaporation effect based on the micro-element-layering method. The key parameters of the safety evaluation model were solved through 420 days of indoor corrosion tests and numerical simulations. Moreover, compared with the test results, the variation law of the lining safety coefficient in the position of the arch foot corrosion and arch foot-waist corrosion was further studied. The results show that: the evaporation sulfate corrosion model of the free surface can accurately reveal the strength degradation mechanism of the tunnel lining, in addition to the temporal and spatial evolution law of the sulfate ions. Moreover, the prediction results of effective strength in the process of safety evaluation were in good agreement with the experimental results. In the stage of tunnel lining corrosion, the decrease in the safety factor of the arch foot corrosion and arch foot-waist corrosion section was slow and then fast within the operation time. The service life of the tunnel depends on the corrosion of the most dangerous parts. The increase in the corrosion area will not reduce the service life of the tunnel.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142561333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental investigation on the soil arching effect induced by deep-buried shield tunneling 深埋盾构隧道诱发土拱效应的实验研究

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-10-30 DOI: 10.1016/j.tust.2024.106161

The mechanism of the soil arching effect determines the overburden pressure of deep-buried shield tunnel, which has not been fully studied. 3 model tests for deep-buried shield tunneling with different vertical pressures acting on the top of the ground were carried out. The changes in the ground stress, displacement, and shear strain during the model tunnel contraction were measured. The experimental results indicated that the two-stage development characteristic of the initially linear rapid decrease followed by the slow reduction was found in the ground reaction curve. Furthermore, the higher the stress level, the slower the development speed of the soil arching, the more pronounced the lag of the soil arching, and the smaller the range of the soil arching. The development of the shear band was controlled by the stress-dependent soil dilatancy. Under the low-stress level, the shear band above the tunnel develops vertically upwards. While under high-stress levels, the shear bands tilt towards both sides. The relevant research results will lay a solid foundation for accurately determining the load of the deep-buried tunnel.

土拱效应的机理决定了深埋盾构隧道的覆土压力，而这一机理尚未得到充分研究。研究人员进行了 3 次深埋盾构隧道模型试验，试验期间地表承受了不同的垂直压力。测量了模型隧道收缩过程中地应力、位移和剪应变的变化。实验结果表明，地层反力曲线呈现出先线性急剧下降后缓慢下降的两阶段发展特征。此外，应力水平越高，土壤起拱的发展速度越慢，土壤起拱的滞后性越明显，土壤起拱的范围越小。剪切带的发展受制于应力的土壤膨胀性。在低应力水平下，隧道上方的剪切带垂直向上发展。而在高应力水平下，剪力带则向两侧倾斜。相关研究成果将为准确确定深埋隧道的荷载奠定坚实的基础。

引用次数: 0

Research and application of dust removal performance optimization of exhaust ventilation system in fully-mechanized excavation rock tunnel 全机械化开挖岩石隧道排风系统除尘性能优化研究与应用

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-10-29 DOI: 10.1016/j.tust.2024.106160

In coal mine tunnels, geotechnical engineering tunnels, and other underground semi-enclosed workspaces, tunneling operations generate significant dust. Most current dust control technologies rely on forced ventilation system or long-pressure and short-extraction system, which often lead to airborne dust spreading towards the tunnel’s rear, resulting in severe dust pollution. To address this issue, numerical simulation employing the Euler-Lagrange method was used to investigate the impact of the exhaust duct inlet position, ventilation air volume, and suction hood structure on the dust removal efficiency of exhaust ventilation technology. The dust distribution law of the tunnel workface under the condition of exhaust ventilation was revealed. The results show that the exhaust ventilation effectively manages dust at the forefront of the tunnel, primarily concentrating at ground level and near the exhaust duct’s sides. Optimal conditions include maintaining the distance between the exhaust duct inlet and the workface (L) within 4 m for improved visibility and control over dust concentrations in the breathing zone. Increasing air volume (Q) to 500 m3/min enhances lateral dust diffusion control, while adopting a round table-shaped suction hood further reduces dust concentration within the tunnel. Field tests implementing the optimized exhaust ventilation system significantly reduces dust levels. Specifically, at the driver’s position, total dust and respiratory dust concentrations decreased from 956.53 mg/m3 and 325.46 mg/m3 to 3.78 mg/m3 and 1.81 mg/m3, achieving reduction efficiencies of 99.60 % and 99.44 % respectively. Similarly, at a distance of 10 m from the workface, total dust and respiratory dust concentrations decreased from 621.11 mg/m3 and 230.43 mg/m3 to 2.43 mg/m3 and 1.65 mg/m3, with reduction efficiencies reaching 99.60 % and 99.28 % respectively.

在煤矿隧道、岩土工程隧道和其他地下半封闭工作空间，隧道作业会产生大量粉尘。目前的粉尘控制技术大多依赖于强制通风系统或长压短抽系统，这往往会导致空气中的粉尘向隧道后方扩散，造成严重的粉尘污染。针对这一问题，采用欧拉-拉格朗日法进行了数值模拟，研究了排风管入口位置、通风风量和吸气罩结构对排风技术除尘效率的影响。揭示了隧道工作面在排风条件下的粉尘分布规律。结果表明，排气通风能有效治理隧道前沿的粉尘，主要集中在地面和排气管道两侧附近。最佳条件包括将排气管入口与工作面之间的距离（L）保持在 4 米以内，以提高能见度并控制呼吸区的粉尘浓度。将风量（Q）提高到 500 立方米/分钟可加强横向粉尘扩散控制，而采用圆台形吸气罩可进一步降低隧道内的粉尘浓度。现场测试表明，经过优化的排气通风系统能显著降低粉尘浓度。具体而言，在驾驶员位置，总粉尘浓度和呼吸道粉尘浓度分别从 956.53 mg/m3 和 325.46 mg/m3 降至 3.78 mg/m3 和 1.81 mg/m3，降尘效率分别达到 99.60 % 和 99.44 %。同样，在距离工作面 10 米处，总粉尘浓度和呼吸性粉尘浓度分别从 621.11 毫克/立方米和 230.43 毫克/立方米降至 2.43 毫克/立方米和 1.65 毫克/立方米，降低效率分别达到 99.60 % 和 99.28 %。

{"title":"Research and application of dust removal performance optimization of exhaust ventilation system in fully-mechanized excavation rock tunnel","authors":"","doi":"10.1016/j.tust.2024.106160","DOIUrl":"10.1016/j.tust.2024.106160","url":null,"abstract":"<div><div>In coal mine tunnels, geotechnical engineering tunnels, and other underground semi-enclosed workspaces, tunneling operations generate significant dust. Most current dust control technologies rely on forced ventilation system or long-pressure and short-extraction system, which often lead to airborne dust spreading towards the tunnel’s rear, resulting in severe dust pollution. To address this issue, numerical simulation employing the Euler-Lagrange method was used to investigate the impact of the exhaust duct inlet position, ventilation air volume, and suction hood structure on the dust removal efficiency of exhaust ventilation technology. The dust distribution law of the tunnel workface under the condition of exhaust ventilation was revealed. The results show that the exhaust ventilation effectively manages dust at the forefront of the tunnel, primarily concentrating at ground level and near the exhaust duct’s sides. Optimal conditions include maintaining the distance between the exhaust duct inlet and the workface (L) within 4 m for improved visibility and control over dust concentrations in the breathing zone. Increasing air volume (Q) to 500 m3/min enhances lateral dust diffusion control, while adopting a round table-shaped suction hood further reduces dust concentration within the tunnel. Field tests implementing the optimized exhaust ventilation system significantly reduces dust levels. Specifically, at the driver’s position, total dust and respiratory dust concentrations decreased from 956.53 mg/m3 and 325.46 mg/m3 to 3.78 mg/m3 and 1.81 mg/m3, achieving reduction efficiencies of 99.60 % and 99.44 % respectively. Similarly, at a distance of 10 m from the workface, total dust and respiratory dust concentrations decreased from 621.11 mg/m3 and 230.43 mg/m3 to 2.43 mg/m3 and 1.65 mg/m3, with reduction efficiencies reaching 99.60 % and 99.28 % respectively.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of the characteristics of progressive erosion and the formation mechanism of debris flow inrush: Numerical simulation and its application 分析泥石流冲刷的渐进侵蚀特征和形成机理：数值模拟及其应用

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-10-28 DOI: 10.1016/j.tust.2024.106150

Unlike water inrush occurring in karst and faults, debris flow inrush involves a greater number of debris such as mud and sand, and exhibit a more complex evolution process of disaster, characterized by significant progressive erosion phenomenon. At present, the progressive erosion characteristics from fine particles to coarse particles before the burst of debris flow inrush is still unclear, and there is a lack of model to predict the volume of debris flow inrush. In this study, the debris flow inrush accidents of Anshi tunnel crossing the contact zone are introduced. Then, using a coupled computational fluid dynamics and discrete element method (CFD-DEM), the debris flow inrush is simulated in multi-scales: from sample-scale to engineering-scale. The erosion characteristics and friction angle degradation during progressive erosion in sample-scale, and the formation mechanism of debris flow inrush in engineering-scale are studied. Finally, based on the results of multi-scale simulations, a model to predict the volume of debris flow inrush considering progressive erosion is established. The reliability of the model is verified by comparison with volume of debris flow inrush of Anshi tunnel. The results of this study contribute to understanding the formation mechanism of debris flow inrush and predicting its volume.

与发生在岩溶和断层中的水流冲刷不同，泥石流冲刷涉及的泥沙等碎屑数量较多，灾害演化过程较为复杂，具有明显的渐进侵蚀现象。目前，泥石流迸发前从细颗粒到粗颗粒的渐进侵蚀特征尚不明确，也缺乏泥石流迸发量的预测模型。本研究介绍了安石隧道穿越接触带的泥石流冲刷事故。然后，利用计算流体力学和离散元耦合方法（CFD-DEM），对泥石流涌入进行了从样本尺度到工程尺度的多尺度模拟。研究了样品尺度下渐进侵蚀过程中的侵蚀特征和摩擦角衰减，以及工程尺度下泥石流冲刷的形成机理。最后，在多尺度模拟结果的基础上，建立了考虑渐进侵蚀的泥石流冲刷量预测模型。通过与安石隧道泥石流涌入量的对比，验证了该模型的可靠性。研究结果有助于理解泥石流涌入的形成机理并预测其涌入量。

{"title":"Analysis of the characteristics of progressive erosion and the formation mechanism of debris flow inrush: Numerical simulation and its application","authors":"","doi":"10.1016/j.tust.2024.106150","DOIUrl":"10.1016/j.tust.2024.106150","url":null,"abstract":"<div><div>Unlike water inrush occurring in karst and faults, debris flow inrush involves a greater number of debris such as mud and sand, and exhibit a more complex evolution process of disaster, characterized by significant progressive erosion phenomenon. At present, the progressive erosion characteristics from fine particles to coarse particles before the burst of debris flow inrush is still unclear, and there is a lack of model to predict the volume of debris flow inrush. In this study, the debris flow inrush accidents of Anshi tunnel crossing the contact zone are introduced. Then, using a coupled computational fluid dynamics and discrete element method (CFD-DEM), the debris flow inrush is simulated in multi-scales: from sample-scale to engineering-scale. The erosion characteristics and friction angle degradation during progressive erosion in sample-scale, and the formation mechanism of debris flow inrush in engineering-scale are studied. Finally, based on the results of multi-scale simulations, a model to predict the volume of debris flow inrush considering progressive erosion is established. The reliability of the model is verified by comparison with volume of debris flow inrush of Anshi tunnel. The results of this study contribute to understanding the formation mechanism of debris flow inrush and predicting its volume.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comprehensive identification and assessment of clastic rock and water-bearing breccia for water and mud inrush in tunnel: A case study 全面识别和评估碎屑岩和含水角砾岩对隧道水和泥浆涌入的影响：案例研究

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-10-28 DOI: 10.1016/j.tust.2024.106156

Clastic rock and breccia are mostly developed in fault fracture zones. Due to their poor stability and easy occurrence of water structures, tunnels are prone to collapse, water inrush and other disasters when encountering clastic rock and breccia, which seriously affects the safety of tunnel construction. In order to reduce the impact of such disasters on construction, the paper takes the No.4 branch tunnel of Xianglu Mountain in Yunnan as an example, and proposes a seismic ahead prospecting method − tunnel resistivity ahead prospecting method − advanced drilling method − cross-hole resistivity tomography method identification system for clastic rock and water-bearing breccia. The identification system integrates drilling methods and geophysical methods to obtain wave velocity information, reflection information, resistivity information and lithology information in the study area. The obtained information is used to jointly interpret the overall lithology fragmentation degree, lithology interface, abnormal water-bearing position, detailed lithology information and water-conducting channel distribution in the study area, so as to complete the identification and evaluation of the lithology characteristics and abnormal structure distribution of the study section. In addition, the study used the joint interpretation results to analyze the mechanism of water and mud inrush in the study section from the aspects of structure and mechanics, and evaluated the possibility of water and mud inrush in the study section. The method proposed in this paper effectively identifies and evaluates the distribution of clastic rock and water-bearing breccia in front of the tunnel face, and effectively avoids the occurrence of tunnel geological disasters.

碎屑岩和角砾岩多发育于断层破碎带。由于其稳定性差，易出现水构造，隧道在遇到碎屑岩和角砾岩时容易发生坍塌、涌水等灾害，严重影响隧道施工安全。为减少此类灾害对施工的影响，本文以云南香鹿山4号支洞为例，提出了碎屑岩及含水角砾岩地震超前勘探法-隧道电阻率超前勘探法-超前钻探法-横洞电阻率层析成像法识别系统。该识别系统综合了钻探方法和地球物理方法，以获取研究区域的波速信息、反射信息、电阻率信息和岩性信息。利用所获得的信息，联合解释研究区的整体岩性破碎程度、岩性界面、异常含水位置、详细岩性信息和导水通道分布，从而完成对研究断面的岩性特征和异常构造分布的识别和评价。此外，研究还利用联合解释成果，从构造、力学等方面分析了研究断面水、泥浆涌入的机理，评价了研究断面水、泥浆涌入的可能性。本文提出的方法有效地识别和评价了隧道工作面前方碎屑岩和含水角砾岩的分布，有效地避免了隧道地质灾害的发生。

{"title":"Comprehensive identification and assessment of clastic rock and water-bearing breccia for water and mud inrush in tunnel: A case study","authors":"","doi":"10.1016/j.tust.2024.106156","DOIUrl":"10.1016/j.tust.2024.106156","url":null,"abstract":"<div><div>Clastic rock and breccia are mostly developed in fault fracture zones. Due to their poor stability and easy occurrence of water structures, tunnels are prone to collapse, water inrush and other disasters when encountering clastic rock and breccia, which seriously affects the safety of tunnel construction. In order to reduce the impact of such disasters on construction, the paper takes the No.4 branch tunnel of Xianglu Mountain in Yunnan as an example, and proposes a seismic ahead prospecting method − tunnel resistivity ahead prospecting method − advanced drilling method − cross-hole resistivity tomography method identification system for clastic rock and water-bearing breccia. The identification system integrates drilling methods and geophysical methods to obtain wave velocity information, reflection information, resistivity information and lithology information in the study area. The obtained information is used to jointly interpret the overall lithology fragmentation degree, lithology interface, abnormal water-bearing position, detailed lithology information and water-conducting channel distribution in the study area, so as to complete the identification and evaluation of the lithology characteristics and abnormal structure distribution of the study section. In addition, the study used the joint interpretation results to analyze the mechanism of water and mud inrush in the study section from the aspects of structure and mechanics, and evaluated the possibility of water and mud inrush in the study section. The method proposed in this paper effectively identifies and evaluates the distribution of clastic rock and water-bearing breccia in front of the tunnel face, and effectively avoids the occurrence of tunnel geological disasters.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Risk assessment of shield construction adjacent to the existing shield tunnel based on improved nonlinear FAHP 基于改进的非线性 FAHP 对邻近现有盾构隧道的盾构施工进行风险评估

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-10-28 DOI: 10.1016/j.tust.2024.106154

To solve the problem that the traditional fuzzy Analytic Hierarchy Process (FAHP) cannot reflect the influence of prominent risk indexes on the evaluation results, a new risk assessment model of shield construction adjacent to the existing shield tunnel was established by introducing nonlinear operators into the traditional FAHP. A risk assessment index system including 5 primary risk indexes and 21 secondary risk indexes and risk assessment criteria were established for shield construction adjacent to the existing shield tunnel. The game theory was used to calculate the combination weights, which comprehensively consider the advantages of subjective and objective weights. The certainty was obtained through cloud model calculation, and then the membership degree vector was obtained to construct the fuzzy relationship matrix. Introducing nonlinear operators to comprehensively analyze the weights and fuzzy relationship matrices. Based on the principle of maximum membership degree, the final risk level result was obtained. The new model was applied to a case study of the risk assessment of shield construction of Changsha Metro Line 2, which is adjacent to Changsha Metro Line 4. The results show that: (a) The risk levels of sample 1 and sample 3 were level Ⅲ and sample 2 was level Ⅱ. The result was consistent with the actual situation which validates the applicability and accuracy of the employed methodology. (b) Compared with the traditional FAHP, the new risk assessment model adequately reflected the prominent impact of adverse risk indexes on risk assessment. Therefore, the new model maximizes the assurance of the rationality of the risk assessment results, which can be feasibly used in applications and guide other similar projects.

为解决传统模糊层次分析法（FAHP）无法反映突出风险指标对评价结果影响的问题，通过在传统FAHP中引入非线性算子，建立了邻近既有盾构隧道盾构施工的新型风险评估模型。建立了包括 5 个一级风险指标和 21 个二级风险指标在内的既有盾构隧道邻近盾构施工风险评估指标体系和风险评估标准。采用博弈论计算组合权重，综合考虑了主观权重和客观权重的优势。通过云模型计算得到确定性，然后得到成员度向量，构建模糊关系矩阵。引入非线性算子，综合分析权重和模糊关系矩阵。根据最大成员度原则，得到最终的风险等级结果。将新模型应用于与长沙地铁 4 号线相邻的长沙地铁 2 号线盾构施工风险评估案例研究。结果表明(a) 样本 1 和样本 3 的风险等级为Ⅲ级，样本 2 为Ⅱ级。结果与实际情况相符，验证了所采用方法的适用性和准确性。(b) 与传统的 FAHP 相比，新的风险评估模型充分反映了不利风险指标对风险评估的突出影响。因此，新模型最大限度地保证了风险评估结果的合理性，可用于应用和指导其他类似项目。

{"title":"Risk assessment of shield construction adjacent to the existing shield tunnel based on improved nonlinear FAHP","authors":"","doi":"10.1016/j.tust.2024.106154","DOIUrl":"10.1016/j.tust.2024.106154","url":null,"abstract":"<div><div>To solve the problem that the traditional fuzzy Analytic Hierarchy Process (FAHP) cannot reflect the influence of prominent risk indexes on the evaluation results, a new risk assessment model of shield construction adjacent to the existing shield tunnel was established by introducing nonlinear operators into the traditional FAHP. A risk assessment index system including 5 primary risk indexes and 21 secondary risk indexes and risk assessment criteria were established for shield construction adjacent to the existing shield tunnel. The game theory was used to calculate the combination weights, which comprehensively consider the advantages of subjective and objective weights. The certainty was obtained through cloud model calculation, and then the membership degree vector was obtained to construct the fuzzy relationship matrix. Introducing nonlinear operators to comprehensively analyze the weights and fuzzy relationship matrices. Based on the principle of maximum membership degree, the final risk level result was obtained. The new model was applied to a case study of the risk assessment of shield construction of Changsha Metro Line 2, which is adjacent to Changsha Metro Line 4. The results show that: (a) The risk levels of sample 1 and sample 3 were level Ⅲ and sample 2 was level Ⅱ. The result was consistent with the actual situation which validates the applicability and accuracy of the employed methodology. (b) Compared with the traditional FAHP, the new risk assessment model adequately reflected the prominent impact of adverse risk indexes on risk assessment. Therefore, the new model maximizes the assurance of the rationality of the risk assessment results, which can be feasibly used in applications and guide other similar projects.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142532997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Understanding the longitudinal performance of shield tunnel from settlement to joint behavior by a novel physical modeling system 通过新型物理建模系统了解盾构隧道从沉降到接缝行为的纵向性能

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-10-28 DOI: 10.1016/j.tust.2024.106149

Apart from the settlement trough, the joint behavior in terms of dislocation and opening plays a pivotal role in determining the longitudinal performance of shield tunnel, while they have been less tackled neither on the site nor in the scaled test system. This paper proposes a novel physical modeling system with the emphasis on capturing both the longitudinal settlement trough and circumferential joint behavior of shield tunnel in one test. The test results have been compared with field data, exhibiting similar trends and magnitudes of change. Utilizing this newly proposed test system, relationship between joint dislocation and opening under differential settlement trough is closely revisited and the proportion of these two joint behaviors could be revealed as the responses to the maximum settlement of the troughs. Results show that the development of dislocation between rings is more prominent than joint opening at a small level of settlement and a higher proportion of joint opening would occur as the settlement increases. Besides, a modest linear correlation between the differential settlement and joint dislocation is observed, whereas no clear correlation is evident between the differential settlement and joint opening. Additionally, the paper discusses the adjustments for sensor position when utilizing this system to measure the tunnel heave or radial joint deformation. Overall, the good working performance and high measuring accuracy of the physical modeling system can enable more precise evaluations of tunnel deformation and refined structural behavior under various conditions.

除沉降槽外，脱位和开洞等接缝行为对决定盾构隧道的纵向性能也起着举足轻重的作用，但无论是在现场还是在按比例试验系统中，对这些接缝行为的研究都较少。本文提出了一种新的物理建模系统，重点是在一次试验中捕捉盾构隧道的纵向沉降槽和周向接缝行为。测试结果与现场数据进行了比较，显示出相似的变化趋势和幅度。利用这一新提出的测试系统，我们重新审视了差异沉降槽下接缝错位和开口之间的关系，并揭示了这两种接缝行为的比例对最大沉降槽的响应。结果表明，在较小的沉降水平下，环间错位的发展比接缝张开更为突出，而随着沉降的增加，接缝张开的比例会更高。此外，还观察到差异沉降与接缝错位之间存在适度的线性相关关系，而差异沉降与接缝开裂之间没有明显的相关关系。此外，论文还讨论了利用该系统测量隧道隆起或径向接缝变形时传感器位置的调整问题。总之，物理建模系统具有良好的工作性能和较高的测量精度，能够在各种条件下更精确地评估隧道变形和细化结构行为。

{"title":"Understanding the longitudinal performance of shield tunnel from settlement to joint behavior by a novel physical modeling system","authors":"","doi":"10.1016/j.tust.2024.106149","DOIUrl":"10.1016/j.tust.2024.106149","url":null,"abstract":"<div><div>Apart from the settlement trough, the joint behavior in terms of dislocation and opening plays a pivotal role in determining the longitudinal performance of shield tunnel, while they have been less tackled neither on the site nor in the scaled test system. This paper proposes a novel physical modeling system with the emphasis on capturing both the longitudinal settlement trough and circumferential joint behavior of shield tunnel in one test. The test results have been compared with field data, exhibiting similar trends and magnitudes of change. Utilizing this newly proposed test system, relationship between joint dislocation and opening under differential settlement trough is closely revisited and the proportion of these two joint behaviors could be revealed as the responses to the maximum settlement of the troughs. Results show that the development of dislocation between rings is more prominent than joint opening at a small level of settlement and a higher proportion of joint opening would occur as the settlement increases. Besides, a modest linear correlation between the differential settlement and joint dislocation is observed, whereas no clear correlation is evident between the differential settlement and joint opening. Additionally, the paper discusses the adjustments for sensor position when utilizing this system to measure the tunnel heave or radial joint deformation. Overall, the good working performance and high measuring accuracy of the physical modeling system can enable more precise evaluations of tunnel deformation and refined structural behavior under various conditions.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142532998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Performance evaluation of novel energy-absorbing anchor cables with expansion–friction structures for supporting roadways prone to rock bursts 带膨胀摩擦结构的新型吸能锚索性能评估，用于支撑易受岩爆影响的道路

IF 6.7 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Tunnelling and Underground Space Technology

Pub Date : 2024-10-28 DOI: 10.1016/j.tust.2024.106158

The powerful impact generated by a rock burst in a coal mine roadway can easily cause ordinary steel strand anchor cables to break, detach, and deform. To address these issues, an expansion–friction energy-absorbing structure designed for installation on ordinary steel strand anchor cables was developed, establishing a novel type of energy-absorbing anchor cable. To investigate the macroscopic deformation characteristics and mechanical properties of the expansion–friction structure and evaluate its performance, static tests were conducted on a 5000 kN servo press. The research results indicate that this energy-absorbing structure possesses dual energy absorption characteristics, namely, plastic expansion deformation and frictional sliding energy dissipation. The deformation characteristics manifest as symmetrical plastic deformation and stable friction deformation and exhibit strong controllability, repeatability, and energy absorption stability. In general, as the cone angle and expansion increase, the deformation of the energy-absorbing structure becomes more pronounced. From the perspective of constant resistance, as the cone angle and expansion increase, the constant resistance gradually increases. The stability of the constant resistance is best at cone angles of 10° and 15° and expansion amounts of 0.5 and 1.5 mm, respectively. Based on the principle of energy absorption, an evaluation index for the mechanical performance of the energy-absorbing structure is proposed. The analysis revealed that the constant resistance, unit displacement energy absorption, and total energy absorption ranges of the expansion–friction energy-absorbing structure are 139.60 to 652.88 kN, 0.41 to 0.61 kJ/mm, and 34.25 to 149.25 kJ, respectively. Therefore, it exhibits good static load control and dynamic load energy absorption mechanical performance. This structure can reduce the probability of impact failure that arises with ordinary anchor cables, thereby improving the stability control effect of energy-absorbing and anti-impact anchor cables on the rock surrounding the roadway and achieving effective control of roadway rock bursts.

煤矿巷道岩爆产生的强大冲击力很容易导致普通钢绞线锚索断裂、脱落和变形。为解决这些问题，我们开发了一种膨胀摩擦吸能结构，可安装在普通钢绞线锚索上，建立了一种新型吸能锚索。为了研究膨胀摩擦结构的宏观变形特征和机械性能，并评估其性能，在 5000 kN 伺服压力机上进行了静态测试。研究结果表明，这种吸能结构具有双重吸能特性，即塑性膨胀变形和摩擦滑动消能。变形特性表现为对称的塑性变形和稳定的摩擦变形，具有很强的可控性、可重复性和能量吸收稳定性。一般来说，随着锥角和膨胀量的增加，吸能结构的变形会越来越明显。从恒阻的角度来看，随着锥角和膨胀率的增大，恒阻逐渐增大。当锥角分别为 10°和 15°，膨胀量分别为 0.5 毫米和 1.5 毫米时，恒阻的稳定性最好。根据能量吸收原理，提出了吸能结构力学性能的评价指标。分析表明，膨胀摩擦吸能结构的恒定阻力、单位位移吸能和总吸能范围分别为 139.60 至 652.88 kN、0.41 至 0.61 kJ/mm、34.25 至 149.25 kJ。因此，它具有良好的静载控制和动载吸能力学性能。该结构可降低普通锚索冲击失效的概率，从而提高吸能抗冲击锚索对巷道围岩的稳定控制效果，实现对巷道岩爆的有效控制。

{"title":"Performance evaluation of novel energy-absorbing anchor cables with expansion–friction structures for supporting roadways prone to rock bursts","authors":"","doi":"10.1016/j.tust.2024.106158","DOIUrl":"10.1016/j.tust.2024.106158","url":null,"abstract":"<div><div>The powerful impact generated by a rock burst in a coal mine roadway can easily cause ordinary steel strand anchor cables to break, detach, and deform. To address these issues, an expansion–friction energy-absorbing structure designed for installation on ordinary steel strand anchor cables was developed, establishing a novel type of energy-absorbing anchor cable. To investigate the macroscopic deformation characteristics and mechanical properties of the expansion–friction structure and evaluate its performance, static tests were conducted on a 5000 kN servo press. The research results indicate that this energy-absorbing structure possesses dual energy absorption characteristics, namely, plastic expansion deformation and frictional sliding energy dissipation. The deformation characteristics manifest as symmetrical plastic deformation and stable friction deformation and exhibit strong controllability, repeatability, and energy absorption stability. In general, as the cone angle and expansion increase, the deformation of the energy-absorbing structure becomes more pronounced. From the perspective of constant resistance, as the cone angle and expansion increase, the constant resistance gradually increases. The stability of the constant resistance is best at cone angles of 10° and 15° and expansion amounts of 0.5 and 1.5 mm, respectively. Based on the principle of energy absorption, an evaluation index for the mechanical performance of the energy-absorbing structure is proposed. The analysis revealed that the constant resistance, unit displacement energy absorption, and total energy absorption ranges of the expansion–friction energy-absorbing structure are 139.60 to 652.88 kN, 0.41 to 0.61 kJ/mm, and 34.25 to 149.25 kJ, respectively. Therefore, it exhibits good static load control and dynamic load energy absorption mechanical performance. This structure can reduce the probability of impact failure that arises with ordinary anchor cables, thereby improving the stability control effect of energy-absorbing and anti-impact anchor cables on the rock surrounding the roadway and achieving effective control of roadway rock bursts.</div></div>","PeriodicalId":49414,"journal":{"name":"Tunnelling and Underground Space Technology","volume":null,"pages":null},"PeriodicalIF":6.7,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142532999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0