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1 – 10 of 185Udari Gunarathna, Chaminda Senarathna Bandara, Ranjith Dissanayake and Harsha Munasinghe
The lessons learned from the 2004 tsunami phenomenon fueled the government and other local authorities to strengthen the legitimate background to mitigate such devastation in…
Abstract
Purpose
The lessons learned from the 2004 tsunami phenomenon fueled the government and other local authorities to strengthen the legitimate background to mitigate such devastation in future events. This study aims to propose a standardized tsunami-resilient construction guideline for Sri Lanka by integrating existing local and international standards.
Design/methodology/approach
A comprehensive literature survey was carried out to undertake the study, with a wide-ranging content and thematic analysis of existing tsunami-resilient construction aspects in Sri Lanka. Integrating all existing guidelines with international standards, finally, a consolidated guideline with significant tsunami-resilient building aspects was proposed for stakeholders involved with the resilient built environment in tsunami-prone areas, particularly during the building construction in the coastal belt.
Findings
The existing tsunami-resilient guidelines in Sri Lanka follow similar aspects but in different dimensions. Compared to the international standards, few significant aspects create a gap in local guidelines. Thus, the findings demonstrated that the existing local guidelines must be modified and strengthened by mainstreaming into international practices.
Research limitations/implications
Existing guidelines are more concerned with structural aspects. Nevertheless, proper integration of local and international guidelines would be more favorable to minimizing existing local guidelines’ gaps. Further, a standardized tsunami-resilient building guideline would be a referring document for all stakeholders in tsunami-resilient constructions.
Practical implications
By aligning local guidelines with international standards, the reliability of the guidelines will be increased and direct the built environment to quality disaster-resilient constructions.
Social implications
Through a standardized guideline, the community can rely on tsunami-resilient construction in coastal cities.
Originality/value
The consolidated guideline further contains the essentials of city resilience in tsunamis and would be an excellent reference for relevant stakeholders than aligning with several guidelines.
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Maher Taha El-Nimr, Ali Mohamed Basha, Mohamed Mohamed Abo-Raya and Mohamed Hamed Zakaria
To predict the real behavior of the full-scale model using a scale model, optimized simulation should be achieved. In reinforced concrete (RC) models, scaling can be substantially…
Abstract
Purpose
To predict the real behavior of the full-scale model using a scale model, optimized simulation should be achieved. In reinforced concrete (RC) models, scaling can be substantially more critical than in single-material models because of multiple reasons such as insufficient bonding strength between small-diameter steel bars and concrete, and excessive aggregate size. Overall, there is a shortfall of laboratory and field-testing studies on the behavior of secant pile walls under lateral and axial loads. Accordingly, the purpose of this study is to investigate the validity and the performance of the 1/10th scaled RC secant pile wall under the influence of different types of loading.
Design/methodology/approach
The structural performance of the examined models was evaluated using two types of tests: bending and axial compression. A self-compacting concrete mix was suggested, which provided the best concrete mix workability and appropriate compressive strength.
Findings
Under axial and bending loads, the failure modes were typical. Where the plain and reinforced concrete piles worked in tandem to support the load throughout the loading process, even when they failed. The experimental results were relatively consistent with some empirical equations for calculating the modulus of elasticity and critical buckling load. This confirmed the validity of the proposed model.
Originality/value
According to the analysis and verification of experimental tests, the proposed 1/10th scaled RC secant pile model can be used for future laboratory purposes, especially in the field of geotechnical engineering.
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Xin Meng, Qingyang Ren, Songqiang Xiao, Bin Chen and Hongfei Li
The purpose of this paper is to simulate the tension process of tension-type anchor cable and to explore the mechanical characteristics and tension-torsion coupling effect of…
Abstract
Purpose
The purpose of this paper is to simulate the tension process of tension-type anchor cable and to explore the mechanical characteristics and tension-torsion coupling effect of anchor cable subjected to tension.
Design/methodology/approach
ABAQUS numerical software is applied to construct the numerical models of tension-type anchor cables with different diameters. Through explicit contact, the characteristics of contact between grouting body-anchor cable and grouting body-rock mass are determined. Confining pressure is applied to the model through surface pressure, and drawing force is applied to the model by displacement loading so as to simulate the tension process of the anchor cable.
Findings
The results show that the stress is transmitted in both axial and radial directions in the anchorage section and distributed in a cone. The shear stress in the grouting body is unevenly distributed, and its peak value increases with the rise in confining pressure and anchor cable diameter. The stress characteristics of torque and axial force are basically consistent and evenly distributed in the free section; they gradually decrease in the anchorage section. Due to the tension-torsion coupling effect, the internal stress characteristics of the anchor cable structure vary. On average, the anchorage performance of each anchor cable model is improved by 6.19%.
Originality/value
The proposed method of numerical modelling is effective in addressing the interface contact between the anchor cable and the grouting body and in solving the problem with convergence of calculation. Compared with the indoor test, this method is more suited to collecting the internal mechanical data of the anchor body.
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This paper aims to adopt a comparative method using case law, statutes and secondary literature across both jurisdictions. This paper also draws on various theories of property…
Abstract
Purpose
This paper aims to adopt a comparative method using case law, statutes and secondary literature across both jurisdictions. This paper also draws on various theories of property ownership.
Design/methodology/approach
This paper conceptualises the legal relations embedded within condominium housing and the various theories of property ownership to ascertain how children’s interest fit within this framework. The laws of two jurisdictions, New South Wales and Singapore, are examined to determine how their strata law responds when children’s safety is at stake.
Findings
Drawing on pluralist moral theories of property law, the thesis advanced is that children’s issues within condominiums should not be subject to majoritarian rule especially when their safety is at stake. The paramount guiding value should be ensuring their safety within multi-owned housing communities. Using the law of two jurisdictions, New South Wales and Singapore, the central argument of this paper is that the law in these jurisdictions has rightfully adopted a protective approach towards children in multi-owned properties where their safety is at stake.
Originality/value
The literature on the law of multi-owned housing has largely focused on governance issues such as mediating between the majority owners’ interest with that of the minority owners’ interest. Children in multi-owned developments remain an under investigated area as children’s interests do not fit within the paradigm of majority versus minority interests. The paper advances the argument that children’s interest should be viewed through either a rights-based theory or pluralists’ theories of property law. Lessons from the New South Wales and Singapore experience are also drawn which might prove useful to other jurisdictions.
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The purpose of this paper is to investigate the impact of near-wall treatment approaches, which are crucial parameters in predicting the flow characteristics of open channels, and…
Abstract
Purpose
The purpose of this paper is to investigate the impact of near-wall treatment approaches, which are crucial parameters in predicting the flow characteristics of open channels, and the influence of different vegetation covers in different layers.
Design/methodology/approach
Ansys Fluent, a computational fluid dynamics software, was used to calculate the flow and turbulence characteristics using a three-dimensional, turbulent (k-e realizable), incompressible and steady-flow assumption, along with various near-wall treatment approaches (standard, scalable, non-equilibrium and enhanced) in the vegetated channel. The numerical study was validated concerning an experimental study conducted in the existing literature.
Findings
The numerical model successfully predicted experimental results with relative error rates below 10%. It was determined that nonequilibrium wall functions exhibited the highest predictive success in experiment Run 1, standard wall functions in experiment Run 2 and enhanced wall treatments in experiment Run 3. This study has found that plant growth significantly alters open channel flow. In the contact zones, the velocities and the eddy viscosity are low, while in the free zones they are high. On the other hand, the turbulence kinetic energy and turbulence eddy dissipation are maximum at the solid–liquid interface, while they are minimum at free zones.
Originality/value
This is the first study, to the best of the author’s knowledge, concerning the performance of different near-wall treatment approaches on the prediction of vegetation-covered open channel flow characteristics. And this study provides valuable insights to improve the hydraulic performance of open-channel systems.
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Ruifeng Li and Wei Wu
In corridor environments, human-following robot encounter difficulties when the target turning around at the corridor intersections, as walls may cause complete occlusion. This…
Abstract
Purpose
In corridor environments, human-following robot encounter difficulties when the target turning around at the corridor intersections, as walls may cause complete occlusion. This paper aims to propose a collision-free following system for robot to track humans in corridors without a prior map.
Design/methodology/approach
In addition to following a target and avoiding collisions robustly, the proposed system calculates the positions of walls in the environment in real-time. This allows the system to maintain a stable tracking of the target even if it is obscured after turning. The proposed solution is integrated into a four-wheeled differential drive mobile robot to follow a target in a corridor environment in real-world.
Findings
The experimental results demonstrate that the robot equipped with the proposed system is capable of avoiding obstacles and following a human target robustly in the corridors. Moreover, the robot achieves a 90% success rate in maintaining a stable tracking of the target after the target turns around a corner with high speed.
Originality/value
This paper proposes a human target following system incorporating three novel features: a path planning method based on wall positions is introduced to ensure stable tracking of the target even when it is obscured due to target turns; improvements are made to the random sample consensus (RANSAC) algorithm, enhancing its accuracy in calculating wall positions. The system is integrated into a four-wheeled differential drive mobile robot effectively demonstrates its remarkable robustness and real-time performance.
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Arun G. Nair, Tide P.S. and Bhasi A.B.
The mixing of fuel and air plays a pivotal role in enhancing combustion in supersonic regime. Proper mixing stabilizes the flame and prevents blow-off. Blow-off is due to the…
Abstract
Purpose
The mixing of fuel and air plays a pivotal role in enhancing combustion in supersonic regime. Proper mixing stabilizes the flame and prevents blow-off. Blow-off is due to the shorter residence time of fuel and air in the combustor, as the flow is in supersonic regime. The flame is initiated in the local subsonic region created using a flameholder within the supersonic combustor. This study aims to design an effective flameholder which increases the residence time of fuel in the combustor allowing proper combustion preventing blow-off and other instabilities.
Design/methodology/approach
The geometry of the strut-based flameholder is altered in the present study to induce a streamwise motion of the fluid downstream of the strut. The streamwise motion of the fluid is initiated by the ramps and grooves of the strut geometry. The numerical simulations were carried out using ANSYS Fluent and are validated against the available experimental and numerical results of cold flow with hydrogen injection using plain strut as the flameholder. In the present study, numerical investigations are performed to analyse the effect on hydrogen injection in strut-based flameholders with ramps and converging grooves using Reynolds-averaged Navier–Stokes equation coupled with Menter’s shear stress transport k-ω turbulence model. The analysis is done to determine the effect of geometrical parameters and flow parameter on the flow structures near the base of the strut where thorough mixing takes place. The geometrical parameters under consideration include the ramp length, groove convergence angle, depth of the groove, groove compression angle and the Mach number. Two different strut configurations, namely, symmetric and asymmetric struts were also studied.
Findings
Higher turbulence and complex flow structures are visible in asymmetric strut configuration which develops better mixing of hydrogen and air compared to symmetric strut configuration. The variation in the geometric parameters develop changes in the fluid motion downstream of the strut. The fluid passing through the converging grooves gets decelerated thereby reducing the Mach number by 20% near the base of the strut compared to the straight grooved strut. The shorter ramps are found to be more effective, as the pressure variation in lateral direction is carried along the strut walls downstream of the strut increasing the streamwise motion of the fluid. The decrease in the depth of the groove increases the recirculation zone downstream of the strut. Moreover, the increase in the groove compression angle also increases the turbulence near the base of the strut where the fuel is injected. Variation in the injection port location increases the mixing performance of the combustor by 25%. The turbulence of the fuel jet stream is considerably changed by the increase in the injection velocity. However, the change in the flow field properties within the flow domain is marginal. The increase in fuel mass flow rate brings about considerable change in the flow field inducing stronger shock structures.
Originality/value
The present study identifies the optimum geometry of the strut-based flameholder with ramps and converging grooves. The reaction flow modelling may be performed on the strut geometry incorporating the design features obtained in the present study.
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Shivani Chouhan, Aishwarya Narang and Mahua Mukherjee
In the event of a disaster, educational institutions like schools serve as lifeline buildings. Hence, it is crucial to safeguard these buildings for the communities that may…
Abstract
Purpose
In the event of a disaster, educational institutions like schools serve as lifeline buildings. Hence, it is crucial to safeguard these buildings for the communities that may depend on the school as a disaster shelter and aid center. Thus, this paper aims to conduct a multihazard risk assessment survey at 50 schools (with 246 building blocks) in Dehradun.
Design methodology approach
The past few decades have witnessed the impact of multihazard frequency in Uttarakhand, India, due to the geographical features of the Himalayas and its neo-tectonic mountain-building process. Dehradun is the capital of Uttarakhand state and comes under seismic zone IV, which is highly prone to earthquakes.
Findings
The hazard assessment is divided into two types of surveys: first, building-level surveys that include rapid visual screening, nonstructural risk assessment and fire safety audit, and second, campus-level surveys that include vulnerability analysis for earthquake, flood, industrial hazard, landslide and wind.
Social implications
This paper will list several gaps and unrecognized practices in the region that increase the schools’ multihazard risk. The study’s outcome will help prioritize the planning of disaster awareness, retrofitting execution, future construction practices and decision-making to minimize the risk and prepare the school for the upcoming disasters.
Originality value
Physical data were collected by the author to determine the multihazard risk analysis in 50 schools in the Dehradun District of Uttarakhand, India. The building- and campus-level surveys have been used to generate a database for the retrofit and renovation process for each individual school to use their budget fruitfully and in a planned way. The survey conducted is more effort and a more detailed risk evaluation which necessitates effectively mitigating and ensuring the potential safety of the region’s schools.
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Josefina Jonsson and Johan Gaddefors
This study aims to discuss how an online community interacts with a local community during the entrepreneurial process. By having a contextualized view of entrepreneurship, this…
Abstract
Purpose
This study aims to discuss how an online community interacts with a local community during the entrepreneurial process. By having a contextualized view of entrepreneurship, this study acknowledges the social and spatial dynamics of the process.
Design/methodology/approach
The inductive approach used in this study is empirically anchored in the case “the library revolt”. This paper analysed interviews conducted in a selected region in Sweden and followed a netnographic method to capture the social interactions online. By using qualitative modes of inquiry, this study attempts to illuminate the social aspects of the entrepreneurial process.
Findings
This study shows how social media works as a contextual element in entrepreneurship. By presenting interactions between an online community and a rural community, it is shown how entrepreneurial processes in rural areas can be shaped not only through local community relations but also by online interaction. It illustrates how an online context, where actors are located with their own unique set of resources, contributes to rural development. By being a part of an ongoing process of structuration, we can view the actors are gaining access to the resources online, which contributes to the change happening in a local community.
Originality/value
This study adds to the conversation of the role of context in entrepreneurship studies. Rural entrepreneurship largely discusses the local social bonds and actions, while this study includes the online social bonds as a part of the reality in which entrepreneurship is developed.
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Linsheng Huang, Yashan Chen and Yile Chen
This study aims to explore the relationship between folk religious place-making and the development of urban public spaces and summarize its influence on community network…
Abstract
Purpose
This study aims to explore the relationship between folk religious place-making and the development of urban public spaces and summarize its influence on community network construction and daily behavior to discover the authentic practices and role of folk faith culture in social space.
Design/methodology/approach
Taking Macau's Shi Gandang Temple and its belief culture as an example, on-site research, historical evidence and interviews were used to elaborate and analyze the processes of place-making, social functions, management mechanisms and folk culture to establish a new perception of folk religious place-making in contemporary urban spaces.
Findings
The article argues that the culture of folk beliefs profoundly influences urban spaces and the social management system of Macau and has a positive significance in building the local community and geopolitical relations. In addition, it suggests that the participation of folk religious places in local practices is important as key nodes and emotional hubs of local networks, reconciling conflicts between communities of different backgrounds and driving urban spaces toward diversity while forming a positive interaction and friendly cooperation between regional development and self-contained management mechanisms, governance models and cultural orientations.
Originality/value
This study takes an architectural and anthropological perspective of the impact of faith on urban spaces and local governance, using the Shi Gandang Temple in Macau as an example, to complement related studies.
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