To study single-tunnel fires in concrete immersed tunnels, a fire test was carried out on a concrete immersed tunnel with a longitudinal length of 5.8 m and a large scale of 1:5. Through self-developed heating and cooling systems and an external load provided by a self-balancing reaction frame, we investigated the temperature distribution, spalling degree, crack distribution, deformation performance

Excessive deformation of tunnel lining structures can be identified as a common problem in Eastern China soft ground. Grouting treatment is an effective and common method to actively mitigate excessive cross-sectional deformation of tunnel lining rings in soft soils. However, grouting operations would introduce localized heavy disturbance to the surrounding ground around the grouting nozzles, causing

This paper experimentally studied the maximum temperature and ceiling temperature decays in a naturally ventilated tunnel designed with a transverse cross-passage. Influence of longitudinal fire location on the thermal temperature distribution was predominately investigated. A series of experimental tests were conducted in a 1/15 model tunnel with pool fires loaded into five different fuel pans. Meanwhile

In engineering practice, a large-diameter shield tunnel frequently extends through multi-layered strata. The behaviour of tunnels is more complex in multi-layered strata, but many designs are still constructed with the assumption that the soil is uniform. In this study, centrifuge tests and FEM analysis are conducted to investigate the mechanical behaviour of a large-diameter shield tunnel through

The groundwater inflow into the tunnel will cause various adverse effects on the tunnel and a proper estimation of the groundwater inflow is of great significance for tunnel drainage system design. In this paper, a semi-analytical solution, which considers the anisotropic permeability of the soil mass, is developed to assess the steady-state groundwater inflow into the tunnel. The solution is developed

In both design and research, the model configuration of an isolated concrete segment working under the solely action of longitudinal jack forces is generally adopted as representative of the most onerous loading scenario borne by the segments of concrete segmental linings (CSLs) during tunnelling. The influence of TBM transverse actions, i.e. tail seal pressures and the transverse component of jack

Tehran metro line 6-south extension (ML6-SE) project passes beneath a congested residential area. To limit the ground surface settlement and to avoid structural damages to the buildings, ground surface settlements are carefully measured in consecutive sections perpendicular to the tunnel alignment with 10–15 m spacing. In this study, the relationships between maximum surface settlement and its influential

Recent research works into the design and response evaluation of deep diaphragm walls and induced settlements to adjacent buildings demonstrated that the nonlinear behavior of surrounding soil, cracking effects affecting the structural members’ flexural rigidity and spatial variability of soil parameters are a prerequisite for a rigorous analysis of serviceability performance. However, as a result

With the surge of extra-long tunnels, the vertical shafts are widely used to shorten the construction period and become a part of the ventilation system during the operation period. Because of the towering mountains, the depth of vertical shafts is usually about 100 m or more, which is quite different from those of urban road tunnels. As a result, it is indispensable to set up perfect smoke extraction

The assumption of cement grouts as ‘Bingham fluids’ has thus far facilitated the development of simplified analytical tools for rock grouting design. However, from a practical standpoint the use of the Bingham constitutive law throughout the design phase has several shortcomings that merit being more systematically addressed. For instance, the known key attributes of cementitious suspensions, e.g.

Deformation of the surrounding rock is an anticipated geological hazard when driving tunnels through soft rock. If deformation is not restricted, it can lead to serious engineering safety hazards. Therefore, studying the factors that affect the deformation of soft rock tunnels is highly significant. This study selected twelve main influencing factors involving subjective and objective factors and four

Given the importance of road tunnels in a transportation network, it is essential to quantitatively assess and predict tunnel functionality loss due to disruptive events. In this study, a stochastic event simulation model was developed to evaluate the resilience of tunnel infrastructure, quantified using a functionality metric as a function of loss in traffic capacity and its duration. The model consists

Currently, research on the underground structures seismic fragility is still in its infancy state. In this study, we carried out numerical simulation on soil-underground structure system (SUSI) by taking the Daikai metro station damaged in the Kobe earthquake as analysis object. Considering input ground motion characteristics, based on incremental dynamic analysis (IDA method), a statistical numerical

Slurry support, which is established by slurry infiltration, is essential to drilling with a slurry shield. In highly permeable soils, the slurry penetrates the ground and the required support force cannot be built up. Hence, large particles are usually added to the slurry to form filter cakes so that the slurry pressure can be applied on the excavation face successfully. In this paper, a series of

Unprecedented rail transit development in China’s megacities has boosted the utilization of metro-led underground space (MUS). Vigorous MUS is critical for sustainable underground space use and urban development. To date, the urban vitality of MUS based on multi-source big data has been far less researched. Although the mechanism and influence factors of MUS vitality have been revealed in previous

The drainage of mountain tunnels can cause groundwater loss and result in shallow groundwater depletion, which jeopardizes terrestrial vegetation. The impact of tunnel drainage on vegetation can be examined from a physiological perspective using monitoring techniques or evaluated as one item in an environmental assessment of the entire tunnel project. Nevertheless, few previous studies have quantitatively

The interaction between multiple fires is complex, in which the theory of single fire is not applicable. This study focuses on the combustion characteristics and temperature distribution of two pool fires with different transverse locations in a model tunnel under natural ventilation. In this study, 84 groups of combustion experiments of two ethanol pool fires were designed by varying the spacing between

Timely and reasonable matching of the control parameters and geological conditions of the rock mass in tunnel excavation is crucial for hard rock tunnel boring machines (TBMs). Therefore, this paper proposes an intelligent decision method for the main control parameters of the TBM based on the multi-objective optimization of excavation efficiency and cost. The main objectives of this method are to

A gas explosion is one of the main hazards of underground utility tunnels (UUTs), and the explosion overpressure can have catastrophic consequences. A pressure relief opening (PRO) can be an effective method of reducing the risk of an explosion. However, most existing UUTs in China are not configurated with a PRO. Therefore, the present study proposes a risk-based PRO design to explore the optimal

Prediction of the further mechanical behaviors is vitally important for tunnel engineering to prevent disasters and maintain stability. It is a challenge for most existing researches to couple multiple influence factors. This study aims to develop a novel Load-Temporal (LT) model to predict the further mechanical behaviors of structure using machine learning method, which considers the effect of both

Analyzing tunnel excavation behavior involves large deformation issues. For this reason, large deformation analysis method is required to rigorously investigate the actual effect of excavation on surrounding ground. Two major numerical approaches capable of considering large deformations are applied to investigating the effect of tunnel boring machine excavation: coupled Eulerian-Lagrangian (CEL) and

The structural failure of round and egg-shaped sewer pipes is investigated by means of laboratory experiments and finite element method analyses. Two different round pipes are considered, which have an inner diameter of 400 mm and 500 mm, and are respectively referred to as R400 and R500 sewer pipes. The egg-shaped pipe considered in this study has a horizontal inner diameter of 400 mm and a vertical

Response spectrum method (RSM) has been applied in seismic analysis of underground structures considering linear soil-structure interaction (SSI). However, the RSM has two main shortcomings: it does not account for soil nonlinearity and it is computationally inefficient for processing large soil domains. This paper addresses these shortcomings by extending the RSM to consider soil nonlinearity and

Developing a combined surface road and underground logistics system based on a city’s metro network is a sustainable solution to alleviate urban traffic congestion and environmental pollution problems. In this study, we propose a three-stage optimization model with a two-level hub-and-spoke structure to establish an intra-city metro logistics network. First, we establish an entropy-weighted TOPSIS

In light of the rapid development of underground spaces in China and the intense demands of professionals for underground space, the Ministry of Education of the People’s Republic of China has permitted the offering of the urban underground space engineering professional degree program in universities since 2001. This professional degree has now been established in more than 80 universities across

This article investigates seismic demands of underground structures with a rectangular section in a two-dimensional framework subjected to complete passage of shear wave field of motion. The wave field is considered to have different incident angles with the structure. Using the finite element approach, frequency-dependent strain transfer functions for different parts of the structure are estimated

In tunnel fires, hot gas, called a ceiling jet, propagates beneath the ceiling from the fire source to the tunnel portals. The properties of the ceiling jet must be understood for conducting a fire safety assessment. Heat loss to the tunnel walls (ceiling and side walls) significantly affects the property of the ceiling jet movement in the tunnel. This study aims to estimate the influence of the tunnel

Multi-face blasting is one of the most frequently used active rockburst prevention methods in the Polish copper mines. Simultaneous firing of a group of faces generates vibrations which, propagating in the form of para-seismic waves, affect the condition of the rock mass structure and allow to trigger high-energy tremors during the production process. However, the simultaneous firing of explosives

Establishing a suitable TBM performance prediction model is benefit to the machine type selection, project scheduling and budgeting. Some regression equations using rock mass classification parameters had already been set up based on TBM tunneling database, some of which were small. Besides, most of existing equations involved field penetration index (FPI) or the cutter force. Once apply these equations

Aiming at the sealant behavior at the engineering scale, this paper first presents a site investigation on the joint responses to reveal the characteristics of probability distribution and the correlations between joint deformations and leakage. A detailed numerical model verified with experimental data, is established to interpret the multi-dimensional variation law of gasket sealing performance subjected

An experimental investigation on the coupled dynamics of an offshore tunnel-rig system from the element launching to its near-seabed immersion in irregular waves is conducted, where the motions of tunnel/rigs and the tensile forces of the suspension lines are evaluated in a synchronous manner for a wide range of irregular waves. The effect of immersion depth on the coupled dynamics of the tunnel-rigs

The behavior of support-surrounding rock interaction considering pre-reinforcement is investigated in this paper. Since previous analyses give little consideration to the influence of pre-reinforcement on the support-surrounding rock interaction, the equivalent material approach is adopted such that the ground strength is improved as the result of pre-reinforcement. The fictitious support pressure

Jacking force is a controlling factor in design and construction of pipe jacking. To date, there is few researches focused on prediction of jacking force in frozen ground. Therefore, this paper investigates the main geotechnical issues, including the jacking force and pipe-soil interaction of pipe jacking in frozen ground. Firstly, a series of numerical simulations and comparative analyses with theoretical

The damage evolution of segmental joints under compression–bending loads is critical in the structural design and strengthening of segmental structures. In this study, a loading device that can maintain the pure bending state of the joint is designed based on the deficiency of existing test methods in boundary conditions. Failure tests under positive and negative bending are performed to investigate

Conventional geophysical methods face many challenges in urban areas from limited site accessibility to severe industrial interferences. With the fast-paced development in urban area and urban light rail transit system, it is highly desirable to have a high-resolution geophysical method, which is suitable for the complex urban condition with strong background noises and, at the same time, is environment-friendly

Timely recognition of rock fragments and their morphological sizes can allow adjustment of excavation parameters during tunnel boring machine (TBM) tunnelling. Traditional manual inspection strongly relies on the experience and subjective determination of the human operators, and sieving tests cannot be conducted in real time and are energy-consuming. Rock fragments in real-world images are frequently

Unlike the terrigenous site condition, the seabed site is characterized by complex hydrodynamics in the ocean environment (i.e. ocean waves and currents). This paper investigates the significance of the ocean environmental loads on the seismic interactions between the buried immersed tunnel and the surrounding soil undergoing buildup of excess pore water pressure (EPWP) and residual liquefaction. A

In this paper, a novel test setup was proposed to perform mechanical and waterproof tests for rubber gaskets used in tunnel segmental joints. Based on the newly developed setup, it is available to simulate typical joint deformation observed during construction and operation stages, e.g., opening, offset, rotation, and eccentric compression. The components and configurations of the setup were presented

A 1 g shaking table test is conducted to investigate seismic responses of a segmental tunnel in sand under near-fault motions. The tunnel model is assembled with segments, bolts and rubber strips and embedded in a shallow sand ground. The test facility, design and preparation of the tunnel model and the sand ground, as well as selected earthquake motions, are presented in detail. Dynamic responses

This paper presents a case study of super-large cross-section tunnel in Zhuhai, China. The excavation section of Gongbei tunnel is 336.8 m2. The construction method of freezing pipe roof and five-bench fourteen-step excavation is expected to be adopted, which is the first case in the world. The tunnel construction risk is great because the stratum which the tunnel passes through is mainly silt and

A hybrid methodology is proposed to investigate the diesel particulate matter (DPM) concentration distribution in underground mines by using a ventilation network solver and computational fluid dynamics (CFD). Mine ventilation system, one of the most significant and energy-intensive parts of an underground mine, needs to be accurately studied to provide sufficient fresh air to the personnel working

Multi-purpose utility tunnels (MUTs) integrate all underground utilities in one accessible tunnel. MUTs reduce the need for excavations and their associated costs, as well as the resulting traffic congestion. Several MUTs have been implemented in different parts of the world. Their locations have either been politically influenced or selected to preserve heritage sites or to meet the conditions of

Soil/rock interface detection is an essential and critical task in geological site investigation for underground and tunnel projects. The required accuracy is within a few meters both vertically and horizontally. The required resolution poses big challenges to geophysical surveys to be applied in near-surface engineering works. This paper presents a new approach of non-invasive geophysical survey,

Conventional deep excavation support systems (diaphragm wall with inner strut) have fixed length of struts, which can lead to a significant discrepancy between deformations of actual and designed diaphragm wall systems. As a result, failure of support system is likely to occur during the deep excavation. In this paper, a novel deep excavation support system with adjustable strut length was proposed

The predicted performance of a geotechnical system may deviate from the in situ observation due to the uncertainties in the input geotechnical parameters, solution model, and observation error. A precise characterization of these uncertainties is a significant challenge primarily because of limited data availability. The Bayesian theory provides a means for updating these uncertainties by incorporating

Tunnels built in areas subject to earthquake activity must withstand seismic loadings. Covering tunnel liners with a coating layer will be a possible way to mitigate seismic damage to tunnels. In this paper, an analytical solution is developed for the seismic response of deep circular tunnels covered by an isolation layer. Since the cross-section dimension of tunnels is normally much smaller than the

With the development of rapid underground construction, precast assembly underpass (PAU) has been used as an alternative way to replace the traditional cast-in-place underpass. However, only limited research was conducted to investigate the behaviour of longitudinal joints on the ultra-shallow buried structure under long-term surface dynamic loads. Although the underpass segments may not be damaged

A robust numerical model, which can simulate the coupled air flow and heat transfer processes in long tunnels, is essentially required to design and operate the mechanical ventilation system in long tunnels surrounded by high temperature rocks. Due to the extreme scale disparity between tunnel diameter and length (~m vs. ~km), very fine mesh is required to accurately represent the highly-dynamic surrounding

Concentrated stress in deep coal seam is the decisive factor leading to the occurrence of rock burst, and the different stress sources cause high stress in coal seam. To fundamentally reduce the concentrated stress in coal seam that can easily cause rock burst, this paper uses the 5305 working face in Xinhe, Shandong Province, as an example for analysis. The evolution law of high stress concentration

For long-distance rock pipe jacking, the coupled actions of mud float and sediment generate pipe-rock interactions, which are challenging from the analysis point of view and the general methods available for calculating the friction resistance of pipe-soil can lead to unrepresentative results. These friction forces must be quantified properly, as the magnitude of those determines the technical and

Intermediate stiffness culverts behave in a manner between that of rigid structures, where the structural stiffness dominates, and flexible culverts where the soil properties are most important. Analysis and design of intermediate stiffness culverts requires a thorough understanding of soil-structure interaction. In addition the use of recycled concrete aggregate (RCA) as a backfill material to culverts

The Dongping No.1 Tunnel of the Guangdong–Foshan Loop Line Intercity Railway in China passes an existing large-scale underground pipe gallery in water-rich sandy strata through the undercutting method. During construction, controlling the underground pipe gallery deformation is difficult because the water-rich sandy strata can easily become unstable. To deal with this problem, this paper proposes a

Claystone is considered as a potential host rock for radioactive waste disposal at great depth in many countries. Considerable quantity of gas can be generated in a deep geological repository (DGR) due to several processes, which may affect the integrity of the host rock and the safety of the DGR. Thus, understanding the migration of gas through the host rock is an essential requirement in developing

Geological suitability evaluation for urban underground space (UUS) is essential for effective UUS utilisation and exploitation risk reduction. However, previous research was hampered by limited availability of 3D technology. The 2D data-based evaluation process has led to information loss among underground data, whilst evaluation results without 3D attributes would also impede accurate analysis and

In current structural analyses on segmental linings, the bending stiffness of segmental joints is usually treated as a constant, which results in a deviation in the calculated internal forces and deformation. In view of this, a finite element model of segmental linings is established using one ring and two half rings. An iterative algorithm is designed with a 3D curved surface of bending stiffness

Rock quality is a critical design parameter of rock bolts. However, rock weathering deteriorates rock quality and adversely affects the performance of rock bolts. The objective of this study was to investigate variations in the velocity and predominant frequency of guided waves in rock bolts subjected to rock weathering. In experiments, chemical and mechanical weathering on 10 rock specimens was achieved

Over the past few decades, a large number of precast segmental utility tunnels have been constructed. Intensive research efforts have been devoted to understanding their performance under service and seismic loads. However, the vulnerability of precast segmental utility tunnels against accidental blast loads is seldom discussed. The present study performs a comprehensive numerical investigation on

Optimization of tunnel hood openings is one of the most important technologies that has been developed to effectively reduce micro-pressure waves (MPWs) on high-speed railway lines. Two types of optimization techniques exist: “pattern optimization,” where the location of open windows is optimized, and “area optimization,” where the area distribution of windows is optimized. This paper presents an evaluation

Tunnel excavation in urban areas causes ground movements that could damage existing nearby piled structures. In practice, to protect structures from tunnelling-induced damage, a stiff protective wall can be constructed between the tunnel and the adjacent piled structure. In this paper, results from four hybrid geotechnical centrifuge tests (where data are coupled between the centrifuge and numerical

Reasonable failure path including the failure initiation location and propagation direction is essential in uplift evaluation of highly pressurized caverns. This study investigates the failure initiation behavior of a rock mass that encloses a highly pressurized cavern, taking into account the diverse strength properties of the rock mass. A series of stress analyses in conjunction with failure criteria