To explore the effects of a longitudinal slope, a curve, and their combined action on the eye movement characteristics and driving safety of drivers in extra-long underwater tunnel, vehicle tests are conducted. Their purpose is to obtain data on the pupil area change rate, blink duration, fixation duration, and average saccade time when a driver passes through each longitudinal slope and curve combination

Considering the increasingly complex and interconnected subway tunnels linking cities, this review argues that the overall reliability of tunnel engineering is crucial for protection when subjected to loads caused by major catastrophes, particularly earthquakes. Therefore, the key topic of this paper is the application of the resilience concept for shield tunnel structure seismic resilience assessment

In this paper, the seismic performance of the underground large-scale frame structure (ULSFS) is thoroughly investigated aiming at the drift deformation and rotation deformation of vulnerable positions, and the multi-dimensional fragility analysis of the ULSFS is further developed based on the internal relationship of different seismic performance evaluating indexes. Employing the increment dynamic

The flicker effect caused by the periodical succession of bright and dark bands on the road surface and tunnel walls can momentarily distract drivers and poses a safety concern. Low-mounting-height luminaires are typically used to illuminate long underground roads. However, the resulting flicker effects persist for longer duration, which can cause accidents. Although flicker frequencies have been extensively

As an effective way to facilitate the increasing demand for reliable infrastructure, energy supply and sustainable urban development, underground utility tunnels have been developed rapidly in recent years. Due to the widespread distribution of utility tunnels, the safe operation of natural gas pipelines accommodated in utility tunnels has caused great concern considering fire, explosion, and other

The Hoek–Brown (HB) failure criterion provides reasonable estimates of the peak strength of isotropic rocks for shear failure; however, this is less so for tensile fractures. Hoek and Brown advised against the direct application of the HB criterion during excavation at deep depths and introduced a tension cut-off (TC) based on reliable extension test data. However, its influence on rock structures

To understand the formation of lighting-related traffic bottlenecks along the long freeway tunnels in the daytime, this study develops an intelligent driver model incorporating the location-dependent lighting-related desired speed (IDM-LLDS). This car-following model associates desired speed variations with the lighting-transition-incurred visual adaptation in the portal areas and low illumination

Multiple corrosion defects located in varied orientations are common on pipelines, significantly impacting pipeline conditions. In this work, 3D finite element (FE) based multi-physics field coupling models were developed to model mechano-electrochemical (M−E) interaction between corrosion defects with varied orientations and its effect on pipeline conditions. The effects of the parameters, including

The present study investigates the mechanical behavior of pipes installed via horizontal directional drilling method, a typical trenchless method for highway-crossing pipeline installation, under traffic loads. The effects of both stationary and moving vehicles are considered in the analysis. Results from the static analysis indicate that the pipe experiences maximum stress at its top, with minimum

Understanding the distribution of pore pressure and predicting water inflow are critical in tunnel engineering. In this study, the numerical solutions obtained by ABAQUS are compared with the theoretical solutions derived using the complex variable method (CVM). This comparison clarifies the influence of assuming a constant total hydraulic head along the interface between the grouted zone and soil

The structural deterioration of urban underground pipe networks is the accumulated combined effects of physical, environmental and operational factors during the whole lifecycle. Accurate on-site locating and mapping of pipes and their conditions has been a great challenge for construction, maintenance and emergency response in a dynamic manner. Existing approaches, mostly based on design-centric and

The purpose of this study was to measure internal longitudinal displacements taking place during tunnel excavation and compare them to the displacements predicted using available analytical and empirical formulations. A physical model made with transparent soil permitted exploring the internal soil deformations, within the supporting soils. A soil surrogate made of Magnesium Lithium Phyllosilicate

This paper presents the semi-analytical solutions to predict the three-dimensional ground movements of shallowly buried tunnels in clayey and sandy soils based on the virtual image technique. Both the ground nonuniform convergence and the tunnel ovalization are taken into account in the proposed method. The accuracy of the proposed method is verified by comparing with the results from field monitoring

The tunnel portal is a seismically weak part of the tunnel. To improve the seismic performance of the tunnel portal, reliable portal slope reinforcement measures were investigated, and a series of shaking table tests of the tunnel portal and slope which were reinforced by micropiles were conducted. The test equipment, similarity relation, material, test process, and loading conditions were introduced

Because of high space utilization, elliptical cross-section sometimes is adopted in the design of urban pedestrian underpasses, underground common ditches and subway tunnels. Nevertheless, theoretical models on the blowout failure analysis of shallow elliptical tunnel faces are quite rare. Within the framework of the kinematical approach of limit analysis, deterministic and probabilistic blowout analyses

The present study investigates the mechanical behavior of high-pressure pipelines installed through horizontal directional drilling (HDD), a crucial trenchless installation method, under seismic loads. Utilizing the finite element method and artificial viscoelastic boundary conditions, this paper analyzes the stress response of pipelines subjected to seismic loads in two directions. The seismic loads

The regular detection and diagnosis mechanism for the silting disease of drainage pipelines (SDP) is critical for making dredging decisions and flood forecasting. Simultaneously, there is a complex coupling relationship between the pipeline siltation and the dynamic changes of the inlet and outlet flows. However, the traditional silting detection frameworks of drainage pipelines face difficulties in

It is essential to predict geological risks ahead of a tunnel face during tunnel boring machines (TBMs) excavation to ensure efficient and stable tunnel construction. In this study, a series of lab-scale chamber experiments were conducted to simulate the electrical resistivity and induced polarization (IP) surveys during TBM advancement toward hazardous ground conditions. Various hazardous ground conditions

The Xigeda formation, widely distributed in southwestern China, is a special semi-diagenetic rock with horizontal bedding，which is mudding in water. In order to study the failure law, catastrophe characteristics and catastrophe mechanism of the interbed type to the surrounding rock and structure of Xigeda formation tunnel, this paper, by means of field investigation, indoor test, numerical simulation

An emerging construction method using a concrete box can effectively reduce the risks such as face collapse and extrusion at the launch stage of shield or tunnel boring machine (TBM) tunnelling. It occupies a small construction plant and can be applied to complex urban environments, especially in mountainous cities. However, the failure mechanisms of the tunnel face at the launch stage of the novel

This paper presents a feasibility study on leak detection of buried pipelines using the active distributed temperature sensing (ADTS) method. The proposed solution involves the use of actively heated fiber optic (AHFO) cables arranged parallel to the pipelines, allowing for changes in the thermal properties of the surrounding soil to be captured and correlated with leakage accidents. This problem was

Abstract not available

Abstract not available

Numerical simulation of segmental lining tunnel subjected to internal explosive loading is carried out in this paper based on the arbitrary-Lagrangian-Eulerian (ALE) and finite element (FE) coupled algorithms. A high-fidelity FE model considering assembled features of segmental lining structure is established, and the mapping technique is adopted to accurately simulate the explosion process. The calculated

Numerical methods are widely used to establish seismic fragility curves in the performance-based seismic design for buildings. However, non-linear dynamic analyses for large soil-structure systems are computationally demanding and alternative methods are sought to establish seismic fragility curves for buried structures. This paper proposes a simplified pushover method to calculate the non-linear response

Seismic response and vulnerability of subway station underground structures are greatly influenced by kinematic soil-structure interaction, which is a function of soil properties and stiffness. Therefore, this paper investigates the influence of parameters associated with soil-to-structure relative stiffness (F) on the seismic fragility curves of underground structures. Incremental dynamic analysis

This study focuses on the mechanism of slurry infiltration in front of the tunnel face during the construction of a slurry shield machine. A multi-field transient model is proposed to describe the growth and dissipation of the excess pore water pressure and the deposition of bentonite particles for slurry shield tunneling in the saturated semi-confined aquifer. Based on the conservation principle,

Traditional open-cut and cast-in-place construction methods for subway stations result in significant social and environmental problems, failing to meet green construction and sustainable development requirements. The pipe-jacking method could solve these problems, with the advantages of mechanised trenchless construction and prefabrication. Based on the engineering project of the Shasan station of

The development of subways is currently at its peak and underground structures including subway stations are being constructed on a large scale. However, previous research on seismic risk evaluation of underground structures mainly focuses on the analysis of influencing factors and seismic fragility. There is a lack of research on comprehensive automated seismic risk evaluation from a macro perspective

The shock wave generated after underground blasting might lead to severe catastrophe or irreparable destruction of adjoining underground and ground structures. To investigate the dynamic response of rock masses and adjacent underground openings and induced ground vibrations subjected to underground blasting, a sequence of laboratory tests was implemented with explosive charges and cement mortar blocks

This paper investigates the influence of the hydro-mechanical properties of the tail void grouting material on short and long-term behavior of the tunnel. These characteristics are of high importance affecting the deformations and pore pressure regime around the tunnel as well as forces and deformations in the linings. Various properties of the tail void grouting material including thickness of grouting

Through-wall leakages took place frequently during those excavations in water-rich sandy strata, which often resulted in engineering failures (e.g., global instability of retaining structures and damages to adjacent existing structures) and even injuries and/or fatalities. In spite of this, only few comprehensive studies relevant to this topic have been known in literature to date. During the recent

As the width of segments increases, segmental joints containing three oblique bolts are increasingly used while their flexural behavior is still not clear. Therefore, this paper presents a comprehensive investigation on the flexural behavior of such joints; and the effects of bolt arrangement are also highlighted. A series of full-scale experiments and numerical simulations are first performed to reveal

This paper proposes a new method for evaluating the seismic performance and fragility of large underground structures. A typical underground subway station consisting of a two-story and three-span structure was used as the research subject. Considering the variation of sites and the uncertainty of input ground motions, we developed a finite element model of a nonlinear dynamic soil-underground structure

This paper aims to study the influence of relative density on the working face stability of shield tunnel in sandy cobble stratum. A series of geomechanical model tests were conducted for shield tunnels excavating through loose sample (LS), medium dense sample (MS) and dense sample (DS), respectively. Relative densities of LS, MS and DS are 0.35, 0.55, and 0.75. The method of continuous rotation of

The trend for digitalization in geotechnics and tunnelling of the past decade has been spearheaded by developments in building information modelling (BIM) within these disciplines. While many advances have been achieved, BIM ground modelling remains a challenge since the inherent heterogeneity and uncertainty of the underground are difficult to describe and to model. This paper presents a new concept

In central business districts (CBDs), shallow underground spaces are being rapidly saturated owing to the increasing scale of urban underground development. Compared to shallow underground spaces, deep underground spaces are better suited for the installation of infrastructural facilities, and therefore, they are expected to become important in future urban space development. However, deep underground

If convergences grow so large that the serviceability of a tubbing ring is lost, remedial measures must be taken. In this context, it is useful to reconstruct the displacement history of the tunnel ring in order to gain insight into the evolution of the structural behavior that has led to the current configuration. This challenge is tackled with the help of measured convergences and rigid body kinematics

The full use of underground space is recognized as a necessary means to improve the accessibility of residents and change the spatial distribution of urban population. The dividends generated by the metro operation will increase as the increases in the number of residents attracted to the zone. However, when the number of residents within the zone exceeds a certain threshold, travel accessibility may

Curved tunnels are more likely to have an accident and a fire source due to their physical characteristics. Using a 3D computational fluid dynamics tool with body-fitted grids, three different fire locations were investigated numerically in a series of curved tunnels with a turning radius of 50–1000 m and a heat release rate of 5–15 MW. Results showed that the critical velocity increased with increasing