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This paper aims to analyse the effect of soft soil grouting on the deformation of the closed shield tunnel with the measured data.

Combining the measured data of vertical, horizontal and convergence deformation of the adjacent tunnel during the grouting construction in foundation pit engineering, the influence of grouting on metro tunnel in soft soil area is analyzed.

The researches indicate that early grouting has the main effect on the horizontal displacement of the tunnel; Due to the disturbing effect of the uninterrupted grouting construction on the soil and the transfer pressure of the rheological soil to the bottom of the tunnel, the tunnel is obviously lifted; And the convergence deformation of the tunnel increases caused by the overburden pressure in the vertical direction, so that the tunnel appears the phenomenon of staggered seam, large opening of bolted joint, damaged segment even leakage of water.

The study based on the field monitoring data is rarely reported, especially the topic about inadvertent grouting in soft soil area is likely to cause severe deformation of adjacent metro tunnel.

Infrastructure projects are expected to deliver value to their stakeholders long after completion. Project value is multi-dimensional and subjective and evolves over the project lifecycle. How stakeholders frame the expected value is central to the public debate about proposed infrastructure projects and influences the financing decisions; however, this framing is inadequately understood. The purpose of this paper is to develop new knowledge for shaping infrastructure projects by identifying the ways in which stakeholders frame project value at the project front end.

Three transport infrastructure projects are compared in a qualitative, document-based study. The authors map the dimensions of value at the project front end and identify stakeholders’ approaches to lifecycle-oriented framing of value.

Financial, social and comparative values are dominant in the project front end. The authors frame value into positive and negative dimensions and identify four themes in the lifecycle-oriented framing of value, including uncertainties, timing of cost and benefit realization, project relations and external sponsorship.

The research is limited through the focus on transport infrastructure projects and project front end only, the selection of cases from a single country and the use of document-based data. The systematic analysis approach has yielded novel analytical frameworks that will be useful for further research.

This study identifies value dimensions that are specific to transport infrastructure projects and proposes a framework to assist stakeholders and project managers to better assess and negotiate value when designing their projects.

Regional and comparative values are revealed as novel aspects of value specific to infrastructure projects. The alternative lifecycle-oriented frames offer a new way to understand and structure the co-creation of value and shape negotiation for investment decisions in the project. A portfolio perspective to investment decision making is proposed.

In shield tunneling projects, human, shield machine and underground environment are tightly coupled and interacted. Accidents often occur under dysfunctional interactions among them. Therefore, this paper aims to develop a multi-agent based safety computational experiment system (SCES) and use it to identify the main influential factors of various aspects of human, shield machine and underground environment.

The methods mainly comprised computational experiments and multi-agent technologies. First, a safety model with human-machine-environment interaction consideration is developed through the multi-agent technologies. On this basis, SCES is implemented. Then computational experiments are designed and performed on SCES for analyzing safety performance and identifying the main influential factors.

The main influential factors of two common accidents are identified. For surface settlement, the main influential factors are ranked as experience, soil density, soil cohesion, screw conveyor speed and thrust force in descending order of influence levels; for mud cake on cutter, they are ranked as soil cohesion, experience, cutter speed and screw conveyor speed. These results are consistent with intuition and previous studies and demonstrate the applicability of SCES.

The proposed SCES provides comprehensive risk factor identification for shield tunneling projects and also insights to support informed decisions for safety management.

A safety model with human-machine-environment interaction consideration is developed and computational experiments are used to analyze the safety performance. The novel method and model could contribute to system-based safety research and promote systematic understanding of the safety performance of shield tunneling projects.

The purpose of this paper is to investigate the innovative approaches to further reduce the environmental impacts during the construction of mega transportation infrastructure, particularly for Australia.

As part of this research, the Sydney Metro was exploited as a case study. This included reviewing the elements of reducing the environmental impacts for the Sydney Metro.

This research has found that there are six elements of reducing the environmental impacts of the Australian public transport infrastructure process. Moreover, this research also found that for the Sydney Metro, first, the logistic planning and optimisation was carefully developed followed by the remaining five elements.

The originality of this research consists of carefully examining the Sydney Metro’s environmental implications including its on-going EIA and EPA compliance.

The purpose of this paper is to apply the theory of sociomateriality to exhibit how the social and material are entangled and (re)configured over time and in practice in a particular organization of study.

The authors conduct an ethnographic case study of the North-South metro line project in Amsterdam and use the methods of participant-observation, in-depth interviewing and a desk study.

The authors showcase the process of sociomaterial entanglement by focussing on the history and context of the project, the agency and performativity of the material and sociomaterial (re)configuration via ritual performance. The authors found the notion of performativity not only concern the enactment of boundaries between the social and material, but also the blurring of such boundaries.

Sociomateriality theory remains difficult to grasp. The implication is the need to provide new lenses to engage this theory empirically.

The authors provide a multi-layered lens for organization researchers to engage sociomateriality theory at a contextual, organizational and practice level.

Insights from a historical and contextual perspective can help practitioners to become aware of the diverse and dynamic ways in which social and material entities are entangled and (re)configured over time and in practice.

The authors provide a unique empirical account to exhibit the entanglement and (re)configuration between the social and material in a particular organization of study. This paper studies a tangible organizational setting whereas prior research in sociomateriality mainly focussed on routines in IT and IS. Finally, the authors suggest the ethnographic method to study sociomaterial entanglement from a historical and contextual perspective.

Transfer relations represent analytical solutions of the linear theory of circular arches, relating each one of the kinematic and static variables at an arbitrary cross-section to the kinematic and static variables at the initial cross-section. The purpose of this paper is to demonstrate the significance of the transfer relations for structural analysis by means of three examples taken from civil engineering.

The first example refers to an arch bridge, the second one to the vault of a metro station and the third one to a real-scale test of a segmental tunnel ring.

The main conclusions drawn from these three examples are as follows: increasing the number of hangers/columns of the investigated arch bridge entails a reduction of the maximum bending moment of the arch, allowing it to approach, as much as possible, the desired thrust-line behavior; compared to the conventional in situ cast method, a combined precast and in situ cast method results in a decrease of the maximum bending moment of an element of the vault of the studied underground station by 46%; and the local behavior of the joints governs both the structural convergences and the bearing capacity of the tested segmental tunnel ring.

The three examples underline that the transfer relations significantly facilitate computer-aided engineering of circular arch structures, including arch bridges, vaults of metro stations and segmental tunnel rings.

This study purposes to study the influence of artificial freezing on the liquefaction characteristics of Nanjing sand, as well as its mechanism.

was studied through dynamic triaxial tests by means of the GDS dynamic triaxial system on Nanjing sand extensively discovered in the middle and lower reaches of the Yangtze River under seismic load and metro train vibration load, respectively, and potential hazards of the two loads to the freezing construction of Nanjing sand were also identified in the tests.

The results show that under both seismic load and metro train vibration load, freeze-thaw cycles will significantly reduce the stiffness and liquefaction resistance of Nanjing sand, especially in the first freeze-thaw cycle; the more freeze-thaw cycles, the worse structural behaviors of silty-fine sand, and the easier to liquefy; freeze-thaw cycles will increase the sensitivity of Nanjing sand's dynamic pore pressure to dynamic load response; the lower the freezing temperature and the effective confining pressure, the worse the liquefaction resistance of Nanjing sand after freeze-thaw cycles; compared to the metro train vibration load, the seismic load in Nanjing is potentially less dangerous to freezing construction of Nanjing sand.

The research results are helpful to the construction of the artificial ground freezing of the subway crossing passage in the lower reaches of the Yangtze River and to ensure the construction safety of the subway tunnel and its crossing passage.

The paper aims to predict longitudinal deformation of a tunnel caused by grouting under the tunnel bottom in advance according to the grouting parameters, which can ensure the safety of the tunnel structure during the grouting process and also help to design the grouting parameters.

The paper adopted the analytical approach for calculating the longitudinal deformation of a shield tunnel caused by grouting under a tunnel, including usage of the Mindlin’s solution, the minimum potential energy principle and case validation.

The paper provides a variational method for calculating the longitudinal deformation of a shield tunnel in soft soil caused by grouting under the tunnel, which has high computational efficiency and accuracy.

This paper fulfils an identified need to study how the longitudinal deformation of a shield tunnel in soft soil caused by grouting under the tunnel can be calculated.

The purpose of this study is to identify the causative factors of metro construction safety accidents, analyze the correlation between accidents and causative factors and assist in developing safety management strategies for improving safety performance in the context of the Chinese construction industry.

To achieve these objectives, 13 types and 48 causations were determined based on 274 construction safety accidents in China. Then, 204 cause-and-effect relationships among accidents and causations were identified based on data mining. Next, network theory was employed to develop and analyze the metro construction accident causation network (MCACN).

The topological characteristics of MCACN were obtained, it is both a small-world network and a scale-free network. Controlling critical causative factors can effectively control the occurrence of metro construction accidents. Degree centrality strategy is better than closeness centrality strategy and betweenness centrality strategy.

In practice, it is very difficult to quantitatively identify and determine the importance of different accidents and causative factors. The weights of nodes and edges are failed to be assigned when constructing MCACN.

This study provides a theoretical basis and feasible management reference for construction enterprises in China to control construction risks and reduce safety accidents. More safety resources should be allocated to control critical risks. It is recommended that safety managers implement degree centrality strategy when making safety-related decisions.

This paper establishes the MCACN model based on data mining and network theory, identifies the properties and clarifies the mechanism of metro construction accidents and causations.

India is a rapidly urbanizing developing country with a population of 1.4 Billion. Indian governments have invested USD 50 Billion) in metro rail projects in 18 cities. Metro constructions are multi-stakeholder mega-projects and are prone to a variety of risks. The purpose of this paper is to analyze the risks involved in metro rail construction projects in a densely populated developing country for two types of systems and from two perspectives. Current literature lacks an understanding of similarities and differences in the risks involved in underground and elevated metro projects from clients' and contractors' perspectives, which the paper highlights.

A total of twenty-five risks were identified, categorized and assessed through experts' opinions about the impact and probability of occurrence of the risks through a questionnaire-based survey. The survey respondents included experts in metro rail construction from client and contractor sides. Paper uses a Fuzzy Inference System to calibrate risk magnitude from occurrence probability and impact.

A notable difference was observed in the views of clients and contractors, except for certain common risks. Both stakeholders had different risk perceptions for the underground and elevated metro rail systems.

This study contributes to the risk assessment for different types of metro systems. This research can help policymakers as well as consultants in prioritizing their risk management strategies in developing countries like India.

Highlighting the critical aspects of risks in metro projects in a developing country, this paper also provides system-based and stakeholder-based comparative aspects of risk analysis.