Accurate knowledge of underground utility networks’ placement facilitates various tasks, such as urban development. The most accurate data can be acquired via geodetic surveys using total stations during construction while the trench has yet to be backfilled. However, the period between networks’ instalment and trench backfilling is often short, meaning that surveyors may arrive at construction sites

Coral sand, as a geological material for foundation filling, is widely used for reclamation projects in coral reef areas. The coral sand is characterized by a wide grain size distribution. A series of centrifuge shaking table tests were conducted to explore the seismic response of a shallow buried underground structure in saturated coral sand and coral gravelly sand. The emphasis was placed on comparing

A review concerning the development and performance of water-based fixed fire fighting systems (WFFFS) in road tunnels is presented. Conventional WFFFS types, including automatic sprinkler system, deluge system, and water mist system, have gained recognition as valuable supplements to ventilation systems in combating tunnel fires. Full-scale projects through international collaborations have been instrumental

The effectiveness of pressed-in ventilation system significantly affects the environmental condition inside the tunnel after blasting. Previous studies rarely focus on the ventilation scenario with two fans installed in series at a certain interval on the leaky ventilation ducting, which is very common for super long tunnel. The concept of the combined fan is introduced to consider the equivalent pressure

Estimating the resilience of civil infrastructures is crucial for disaster prevention (i.e. earthquakes), encompassing both above- and underground constructions. However, while below-ground infrastructures are generally acknowledged as less vulnerable than their over-ground counterparts, this aspect has not yet garnered widespread attention. Thus, noting the limited number of seismic response comparisons

The integrity of the excavation tunnel point cloud depends on the effectiveness of registering laser scans at each station. However, the complex surface structure of the excavation tunnels, characterized by a lack of significant features, poses registration challenges. To address these obstacles, we introduce a classification mechanism to the neighbor reweighted local centroid (NRLC) algorithm, resulting

Substantial concrete pouring is common in large-cross-section station tunnels and releases a considerable amount of hydration heat, which negatively affects the quality and reliability of lining structures. Extensive research on the hydration heat of concrete linings in underground tunnels has not yet been conducted. This study investigated the structural temperature and stress caused by hydration

To study the deformation response of tunnel excavation in clayey formations, with a specific focus on the time-dependent behavior of the Solignano tunnel. The investigation employs in-situ experimental tests and numerical simulations, utilizing the viscoelastic-viscoplastic strain-softening (VEVP-SS) constitutive model to accurately represent the stress–strain relationship of clayey flysch geomaterials

A method is presented for estimating deformations due to external lateral loading for full-scale laboratory performance testing of host-internal replacement pipe (IRP) systems. Soil displacements associated with traffic loading and adjacent excavation are described analytically based on prior research. A beam-on-springs finite element (FE) model is developed to represent buried, jointed cast iron (CI)

The use of conventional concrete as the inner lining in double-layer lining shield tunnels presents challenges, including cracking and poor durability. This study proposes a novel double-layer lining structure with Ultra-High Performance Concrete (UHPC) as the secondary lining. The enhancement mechanism of this structure is analyzed through full-scale experiments and refined numerical simulations.

Seismic events have underscored the significant impact of Rayleigh waves on the seismic resilience of shallow-buried tunnels. Existing analytical models often overlook key factors influencing seismic responses, including shear deformations, the rotational inertia of the tunnel cross-section, soil spring shear interaction, and the coupling of axial and transverse dynamic responses. These issues are

To investigate the effect of site specificity on the seismic response of underground structures, two centrifuge shaking table tests under adverse soil site conditions were carried out, considering the case of structures placed in saturated clay sites and saturated sand sites, respectively. Through the comparison of typical test results, the seismic response law of underground structures and soil sites

With a growing focus on safety and energy efficiency in tunnel lighting, Accompanying Vehicle Lighting Length (AVLL) has emerged as a dynamic solution to provide targeted illumination that moves with vehicles. This study investigates the influence of AVLL on driver behavior in extra-long tunnel curves, specifically examining its effects on speed regulation and steering accuracy at various design speeds

In order to solve the problems of large amounts of pollutants, low efficiency of air replacement and serious local concentration of harmful gases in the working space of extra-long railway tunnel, this paper proposed a relay ventilation system for long air cabin of extra-long railway tunnel. Through the analysis of on-site monitoring data and full-size numerical simulation, this paper deeply studies

3D spatial data models are essential in city modelling, providing detailed and accurate representations of urban environments. However, underground urban spaces pose significant challenges for these data models, especially in managing underground utility networks. While most current data models primarily represent city objects, only a few are designed to specifically model utility networks. Data models

The structure of the hydraulic drifter is introduced, and the process of drilling into rocks by the drifter is established as a physical model of rock with three-degree-of-freedom dry friction. Four modes of the physical model are introduced. The solutions of the physical model are divided into three segments. The angular frequency and amplitude of the hydraulic force are taken as control parameters

Hybrid steel fiber reinforced self-compacting concrete (HSFRSCC) is suitable for applying as the concrete matrix material of precast segments, which can ensure the high local bearing capacity and avoid the initial defect. However, there were very limited studies on the triaxial constitutive model and meso-structural mechanism of HSFRSCC. In this research, the closest-packed fiber-aggregate skeleton

Tunnels often unavoidably traverse unfavorable geological structures like faults and joints. These surrounding rock structures can typically be simplified as rock mass structures containing combined defects of holes and fissures. In order to study the whole fracture process of rocks with a hole and collinear hole edge fissures after hole reinforcement, indoor biaxial compression tests were conducted

Amidst the ongoing transformation of urban landscapes worldwide, this study examines the dynamic evolution of Beijing’s urban rail transit network from 2013 to 2022, focusing on the interplay between urban spatial changes and passenger travel behavior. Utilizing an enhanced node-place model and a sophisticated stacking ensemble machine learning approach, we analyze a decade of subway station development

During shield tunnel construction, grouting is injected between the segment and the surrounding rock to ensure structural safety. However, defects may occur because of insufficient or shrunken grouting. Therefore, nondestructive testing (NDT) of grouting defects behind tunnel shield segments is crucial for ensuring the performance of tunnel structures and preventing disasters. In this paper, a shear

The longitudinal bending stiffness is a crucial mechanical parameter influencing the tunnel’s longitudinal deformation. In large-diameter shield tunnels, the internal structure plays a significant role in affecting the mechanical behavior of the segmental lining. This paper developed an analytical solution to the longitudinal equivalent bending stiffness of single-layer and double-layer internal structures

The exponential growth of tunnelling projects worldwide necessitates efficient management of excavated soil, particularly from Earth Pressure Balance Tunnel Boring Machines (EPB-TBMs). This study investigates the temporal evolution of mechanical properties in EPB-excavated soil, focusing on the conditioning process’s impact. Through a comprehensive literature review, gaps in understanding the soil’s

This paper introduces a novel High Bolt-Screw (HBS) active joint that enhances compressive and tensile support in deep subway foundation pits, improving the stability and safety of underground structures. The study provides a comprehensive analysis of the joint’s design, including its working principle, stiffness analysis, parameters, and strength verification. The HBS joint offers a unique design

Precise seismic fragility analysis holds significant importance in the evaluation of seismic resilience for underground structures. However, the conventional seismic fragility analysis of underground structures usually ignores the hybrid epistemic uncertainties caused by the limited samples of both seismic demand and thresholds and deterministic boundaries between different limit states, which can

This study primarily investigates the mechanical responses and failure mechanisms of tunnels adjacent to karst fissures through detailed laboratory model experiments, supplemented by machine learning-interpreted simulations. Utilizing a novel tunnel-karst fissure model test system, we meticulously analysed stress and displacement evolution within the surrounding rock during tunnel excavation, elucidating

The underground water environment in mountain tunnels constitutes a complex system. During tunnel construction, the interaction between tunnel and underground water environment can lead to chain construction accidents and environmental damage. Identifying comprehensive risks of underground water environment effects and making rational decisions are crucial. Considering the diversity, complexity, uncertainty

Differential settlement can cause concentrated deformation in the joints of immersed tunnel during its service stage. In this study, a model for simulating immersion joint was proposed, and tests on immersed tunnels under varying differential settlement were conducted. The mechanical behaviours of joints, including vertical displacement, shear displacement, rotation angle, and joint opening, were systematically

Studies have shown that accidents in tunnels can be more severe than those in open road networks, and drivers are considered the critical factor for such accidents. An in-depth understanding of driver behavior helps analyze pre-accident safety measures and develop policies. Decoration of landscape zones is considered an effective measure for improving the driving environment inside road tunnels and

The issue of crowd evacuation during sudden floods in subway stations has gained increasing attention in recent years. However, previous studies have not sufficiently examined the influence of flood flow characteristics, such as location and velocity, on pedestrian evacuation. This gap has limited the effectiveness of current flood evacuation models for subway stations, restricting their utility in

This study delved into the fundamental relationship between negative emotions and slow walking behaviors in a smoke-filled model-scale tunnel. Behavioral patterns and emotional responses were investigated by video observations and physiological signals. Contrary to previous assumptions, it was revealed that the “slow” was not solely indicative of older people, children, or individuals with disabilities

The precise estimation of water inflow (WI) into the tunnel during the construction phase, as one of the engineering geological hazards, is one of the most critical factors for project advancement and utilization, especially in the early design stages. To address this, the current study developed several predictor networks, including hybrid-optimized supervised learning models such as AdaDelta-recurrent

In the process of tunneling, accurate and timely recognition of the geological type is significant to optimize the control parameters of the tunneling machine, improving tunneling efficiency and avoiding accidents. The shield machine operator in shield tunneling machine cannot directly observe the geological environment due to the closed working environment, so the soft method that can indirectly recognize

Sewers are a critical component of urban infrastructure, presenting significant challenges in efficiently detecting defects. Currently, Convolutional Neural Networks (CNNs) are widely applied in CCTV inspections for defects in sewers. However, images of these defects commonly suffer from dataset imbalance, and CNNs can only capture local features of images, lacking a comprehensive understanding of

This study introduces a global re-localization method for mobile mining vehicles equipped with solid-state LiDAR in underground haulage roadways. The method includes feature extraction from LiDAR data, an improved fast Euclidean clustering algorithm for point cloud classification, and a descriptor based on Delaunay and Extended Delaunay Triangles centered on roadway features. A global re-localization

A hybrid smoothed particle hydrodynamics-discrete element method (SPH-DEM) is proposed to simulate rockburst behavior during deep tunnel excavation. Within this coupled code, the rock mass continuity stress and elastic deformation are computed by solving partial differential equations (PDEs) via the SPH method. Rock cracking is realized by the transition of SPH particles to DEM particles while considering

As a crucial method for mining thick ore bodies, deep-hole blasting provides high production efficiency and low explosive consumption. Its effectiveness is heavily dependent on the optimization of blasting parameters. To refine these parameters, single hole and variable hole spacing multi hole blasting crater tests were conducted in mine tunnels with rock masses exhibiting varying degrees of joint

To obtain comprehensive insight into the damage and strength degradation of surrounding rocks in deeply buried tunnel under thermo-hydro-mechanical (THM) coupling environments, triaxial experiments with real-time acoustic emission (AE) monitoring of granite core samples from the western Sichuan were implemented under THM coupling conditions. A simplified thermal cracking model of granite considering

Deep work shaft excavations have become increasingly common as a preliminary step of tunnel construction. Deep excavation above a multi-aquifer-aquitard system (MAAS) complicates the flow field and stress field surrounding the excavation, inevitably affecting the performance of excavations. However, previous studies with drained or undrained analyses ignored the effects of dewatering-induced groundwater

Rockburst is a phenomenon characterized by spalling or ejection of rock. Severe rockbursts can lead to casualties and equipment damage. The literature review shows that previous research has focused on rockburst in tunnels with burial depths greater than 200 m. However, the formation mechanism of rockburst in tunnels with shallow burial depths (<200 m) within gully environments remains unclear. Researching

The widespread distribution of sandstone and slate interbedded strata in southwestern China makes tunnels within these formations highly susceptible to water and mud inrush disasters due to engineering disturbances and water-pressure coupling effects. Taking the Xinping Tunnel project as an example, this study analyzes and summarizes tunnels’ geological structure, rock mass structure, and water storage

Raise Boring Machines (RBMs) are mechanical miners that are preferred over conventional drilling and blasting methods for drilling / excavating vertical or inclined shafts in mining and construction projects. The use of RBMs not only reduces overall operational costs but also increases profitability. This review paper aims to present empirical, deterministic, and numerical models that are used to predict

This paper investigates the role of masonry elastoplastic constitutive models on tunnelling-induced damage in buildings. A two-stage analysis method (TSAM) is adopted, incorporating input greenfield displacements, 3D masonry walls, and an elastic model for the soil. The paper focuses on four masonry constitutive models that can be readily adopted for routine analysis in industry. Comparison of in-plane

Anchoring rock masses is a commonly applied measure to prevent rockburst, whereas many deep tunnels still encountered rockburst after anchoring with rockbolts. Currently, the absence of suitable evaluation methods impedes the timely grasp and improvement of the rockburst prevention effect. This paper first investigates the alterations of rockburst pit depths before and after anchoring in three deep

The excavation of large-diameter shield tunnels in soft soils inevitably impacts adjacent high-speed railway infrastructure. This study investigates the effects of constructing a 14.02 m large-diameter shield tunnel on the deformation of a nearby high-speed railway subgrade in soft soils of Shanghai, and evaluates the effectiveness of various protective measures. A numerical model was developed to

The deep layered clastic-rock roadways (LCRRs) of the gold mines in southwestern Guizhou, China, are adversely affected by dynamic disturbances such as blasting and mechanical operations, yielding poor roadway stability and unsatisfactory control effectiveness. This study investigates the deformation failure mechanism of a deep LCRR under dynamic disturbance and proposes and validates an optimised

The Kahramanmaraş earthquake sequence of February 6, 2023, has provided an opportunity to investigate the seismic performance of tunnels under very strong ground motions. The field survey conducted following the events revealed limited damages to the tunnels in the affected region despite the very high recorded ground motions. It is therefore important first to examine the reasons for these limited

To improve traffic safety at the entrance of highway tunnels, a comparative analysis of the traffic environment inside and outside the tunnel was conducted, and an improvement scheme based on “linear visual guiding” was developed by considering the human factors. Before and after the improvement of nine experimental tunnels, two batches of vehicle experiments were conducted to analyze the improvement

Most shield tunnels in urban soft clay or mudstone strata are constructed by Earth Pressure Balance shield (EPB shield). When tunneling in similar strata, the clay soils may clog easily in the cutter head, soil chamber or screw conveyor. In mudstone stratum, assessing a reasonable conditioning state of clay soil is key to ensuring improved shield tunnelling efficiency. The fluidity and adhesion of

Two types of pavement material, including concrete and asphalt, have been utilized in road tunnel. Due to the distinct color and reflection characteristics of concrete and asphalt pavements, the lighting effect on the two types of pavements and the visual characteristics of the driver during driving are distinct. However, the impact of pavement types on lighting quality, energy consumption, and drivers’

This paper presents the findings of a field evacuation experiment conducted in an underwater shield tunnel, which involved a random sample of 188 participants of various ages and genders. The experiment utilized an evacuation staircase, and the study employed both the field experiment and a questionnaire to obtain data. The participants’ behavior in the driveway, evacuation staircase, and secure channel

In recent years, the construction of bifurcated tunnels has increased in cities to facilitate the interconnection of urban transportation systems but posing significant fire risks at the same time. In this study, the effect of the ventilation condition and heat release rate (HRR) on flame behavior and temperature distribution in tunnel traffic merging section is studied with scale-model experiments

Subway construction is one of the effective means to boost economic and social development, as well as relieve urban traffic pressure. However, the surface deformation in the process of its operation and maintenance has become one of the most intractable problems faced by urban construction, planning and management departments. This study delved into the surface deformation evolution and underlying

Laboratory model tests and numerical simulations were conducted to investigate the control effect of different arrangements of isolation piles on the additional deformation and stress of tunnels adjacent to pit excavation. Four different arrangements of isolation piles were discussed in this work: arched, curved, double-row, and single-row. The results indicated that considering the burial depth, the

Existing research predominantly highlights the positive factors facilitating the development and utilization of urban underground space (UUS). However, the constraints and challenges should not be overlooked. Recognizing these limiting factors during the strategic planning and management phases of UUS is essential for enhancing utilization efficiency. To comprehensively understand the constraints on

Investigating the mechanical responses and strengthening effects of surcharge-disturbed shield tunnels with varying cross-sections is crucial for ensuring the effectiveness of structural safety evaluations and treatments. This study introduces an elaborate modeling approach for segmental rings of three different sizes. Using calibrated finite element (FE) models and a proposed numerical simulation

Multiple fire source fires in a tunnel may cause serious fire consequences. In the present study, the flame properties and maximum ceiling smoke temperature for two asymmetric fire sources in the tunnel with natural ventilation are studied in detail. A large number of model-scale fire experiments are performed, considering energy release rate ratio ratio and fire source spacing. The results show that

In extra-long tunnels, the dust generated by blasting excavation is difficult to discharge through ventilation, which can easily lead to secondary dust generation, severely affecting the health of construction personnel inside the tunnel and potentially increasing the construction interval. To shorten the dust removal time and enhance efficiency during tunnel blasting, this study utilized a single-hole

Multitudinous natural human-induced flaws exist in the rock mass, which could pose potential risks to the safety of tunnel engineering. To study the dynamic failure properties of the tunnel with a crack in the surrounding rock mass, a series of typical split Hopkinson pressure bar (SHPB) dynamic fracture tests were conducted. A high-speed camera was utilized to record the failure process and digital

The escalation in infrastructure such as highways and high-speed railways has necessitated construction on soft and compressible ground, prompting the adoption of innovative solutions like piled-supported embankments. With the surge in tunnelling for transportations projects, the necessity of constructing tunnels in close proximity to piled embankments has become apparent. This study examines into

The lateral force exerted when two trains pass each other can adversely affect train safety, and this adverse effect becomes more pronounced as the train speed increases. When trains cross paths in tunnels, the aerodynamics differ from those in open lines due to the restrictive nature of tunnel walls. Utilizing the Renormalization Group (RNG) k-ε turbulence model and the “Mosaic” grid method, this