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1 – 10 of over 18000Keyu Chen, Beiyu You, Yanbo Zhang and Zhengyi Chen
Prefabricated building has been widely applied in the construction industry all over the world, which can significantly reduce labor consumption and improve construction…
Abstract
Purpose
Prefabricated building has been widely applied in the construction industry all over the world, which can significantly reduce labor consumption and improve construction efficiency compared with conventional approaches. During the construction of prefabricated buildings, the overall efficiency largely depends on the lifting sequence and path of each prefabricated component. To improve the efficiency and safety of the lifting process, this study proposes a framework for automatically optimizing the lifting path of prefabricated building components using building information modeling (BIM), improved 3D-A* and a physic-informed genetic algorithm (GA).
Design/methodology/approach
Firstly, the industry foundation class (IFC) schema for prefabricated buildings is established to enrich the semantic information of BIM. After extracting corresponding component attributes from BIM, the models of typical prefabricated components and their slings are simplified. Further, the slings and elements’ rotations are considered to build a safety bounding box. Secondly, an efficient 3D-A* is proposed for element path planning by integrating both safety factors and variable step size. Finally, an efficient GA is designed to obtain the optimal lifting sequence that satisfies physical constraints.
Findings
The proposed optimization framework is validated in a physics engine with a pilot project, which enables better understanding. The results show that the framework can intuitively and automatically generate the optimal lifting path for each type of prefabricated building component. Compared with traditional algorithms, the improved path planning algorithm significantly reduces the number of nodes computed by 91.48%, resulting in a notable decrease in search time by 75.68%.
Originality/value
In this study, a prefabricated component path planning framework based on the improved A* algorithm and GA is proposed for the first time. In addition, this study proposes a safety-bounding box that considers the effects of torsion and slinging of components during lifting. The semantic information of IFC for component lifting is enriched by taking into account lifting data such as binding positions, lifting methods, lifting angles and lifting offsets.
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Christoph Sydora, Zhen Lei, Ming Fung Francis Siu, SangHyeok Han and Ulrich Hermann
Heavy industrial construction often relies on large mobile cranes to erect equipment and pre-assembled modules. Engineering calculations are required for the lifting analysis…
Abstract
Purpose
Heavy industrial construction often relies on large mobile cranes to erect equipment and pre-assembled modules. Engineering calculations are required for the lifting analysis where lifting capacity is analyzed to ensure the feasibility of the lifting scenarios. Such engineering calculations are often presented in static formats, e.g. two-dimensional or three-dimensional models. However, it is difficult to help practitioners (e.g. lifting engineers, site crews and operators) understand the complexity of the lifting process and thus operational decisions are often made intuitively. Therefore, this paper aims to introduce a game-based simulation system to allow for interactive analysis of the lifting process to improve lifting efficiency and safety.
Design/methodology/approach
The proposed method treats the mobile crane as a robot with degree-of-freedoms, and the movements are simulated in the Unity game environment. The lifting capacity is calculated dynamically based on the lifting object weight, rigging weight and lifting radius.
Findings
Compared with the four-dimensional visualization, this development has added a dimension of real-time interactive simulation; this allows the users to understand the complexity and feasibility of the lifting process.
Originality/value
The developed prototype has been tested and validated using a real case study from a heavy industrial project with the possibility of generalizing crane lifting configurations.
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Zhiqian Zhang, Wei Pan and Mi Pan
Modular integrated construction (MiC) is the most advanced off-site construction technology. However, the application of MiC for high-rise buildings is still limited and…
Abstract
Purpose
Modular integrated construction (MiC) is the most advanced off-site construction technology. However, the application of MiC for high-rise buildings is still limited and challenging. One critical issue is tower crane layout planning (TCLP) to guarantee safe and efficient multiple crane-lifts for module installation, which, however, has been insufficiently explored. For filling this knowledge gap, this paper aims to systematically explore the critical considerations on TCLP for high-rise MiC to support contractors in determining the optimal crane layout plan.
Design/methodology/approach
This study employed a multimethod strategy. First, previous studies on TCLP and critical features of MiC were reviewed to develop a conceptual model of TCLP considerations. Second, expert interviews with 15 construction planners were conducted to identify the critical TCLP considerations for high-rise MiC. Third, a multicase study with three high-rise MiC projects was undertaken to demonstrate and verify the identified considerations.
Findings
The paper characterises critical considerations on TCLP as performance criteria and influencing factors and identifies 7 critical performance criteria and 25 influencing factors for high-rise MiC. Specifically, the features of MiC (e.g. various modularised layout design, heavyweight and large size of modules) were found to significantly affect the crane layout performance (i.e. technical feasibility, safety and economic efficiency).
Originality/value
The paper is the first-of-its-kind study on crane layout planning for high-rise modular buildings, which contributes a two-stage multicriteria decision-making framework integrated with systematic TCLP considerations. The findings should help contractors determine safe and efficient tower crane layout plans for high-rise MiC projects.
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S. Thomas Ng, Jonathan Shi and Yuan Fang
Many planners and managers prefer to maintain more than enough construction materials on site to avoid valuable labour and plant resources staying idle. Despite the fact that…
Abstract
Purpose
Many planners and managers prefer to maintain more than enough construction materials on site to avoid valuable labour and plant resources staying idle. Despite the fact that minimising the buffer stock would improve the productivity of a construction project, no one likes to take this risk especially when the consequences are not totally clear. This paper aims to identify the possible savings in time and cost due to different amounts of buffer stock on site, by introducing an activity‐based simulation model.
Design/methodology/approach
In this research, details and data of a residential project involving substantial amounts of pre‐cast components are collected. The project participants are asked to unveil the constraints on site and throughout the material delivery and storage processes. Finally, the collected data are fed into the activity‐based construction simulation tool for analysis.
Findings
The results indicate that simulation could help quantify the productivity of resources so as to establish the most suitable strategy for improving the logistics of materials handling in a construction project.
Originality/value
The paper helps construction planners and managers to streamline the flow of construction materials and determine optimal buffer stocks rather than relying on subjective judgement.
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Babur Ozcelik, Fehmi Erzincanli and Fehim Findik
A non‐contact end‐effector was applied to lift three different materials which have different physical properties. These materials are mica (as rigid material), carton (as…
Abstract
A non‐contact end‐effector was applied to lift three different materials which have different physical properties. These materials are mica (as rigid material), carton (as semi‐rigid material) and non‐rigid material (woven fabric). This end‐effector operates on the principle of generating a high‐speed air flow between nozzles and the specimen surface thereby creating a vacuum which levitates the materials with no mechanical contact. In this paper, the handling results of these materials are compared with each other. The changes in the physical behavior of lifting materials were observed during the experimental work. The effect of the various air flow rates on the non‐contact handling clearance gap between the nozzle and the materials were also investigated. As a result, it was observed that the non‐contact end‐effector could be applied to handle different flat materials.
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Hao Zhou and Ehsan Rezazadeh Azar
Steel and reinforced concrete are among the most common structural materials used in the construction industry. Cost and the speed of construction have been usually the main…
Abstract
Purpose
Steel and reinforced concrete are among the most common structural materials used in the construction industry. Cost and the speed of construction have been usually the main criteria when selecting a building’s structural system, whereby the environmental impact of the structural material is sometimes ignored. Availability of an easy-to-use tool for environmental assessment of the structural alternatives could encourage this evaluation in the decision making. The purpose of this paper is to introduce an automated tool for the environmental assessment of the on-site construction processes of a building structural system, which calculates the energy consumption and carbon emissions of the structural system as a parameter for comparison.
Design/methodology/approach
This assessment tool is implemented using a building information modeling (BIM) platform to extract structural elements and their key attributes, such as type, geometrical and locational data. These data are processed together with a productivity database to calculate machine hours, and then predefined energy and carbon inventories are used to assess the energy consumption of the structural system in the erection/installation stage.
Findings
This assessment tool provides an automated and easy-to-use approach to estimate energy consumption and carbon emissions of different structural systems that are modeled in a BIM platform. The results of this tool were within the ranges reported by the available studies.
Originality/value
This research project presents a novel approach to use BIM-based attributes of the structural elements to calculate the required efforts, i.e. machine hours, and assess their energy consumption and carbon emissions during construction processes.
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Stelios Sapountzis, Kathryn Yates, Mike Kagioglou and Ghassan Aouad
This paper seeks to focus on the requirements to manage change, tangible and intangible benefits in a joint approach to deliver outputs on time, to quality and cost without…
Abstract
Purpose
This paper seeks to focus on the requirements to manage change, tangible and intangible benefits in a joint approach to deliver outputs on time, to quality and cost without failing to realise the benefits of the change. The aim of the paper is to demonstrate the need for benefits‐driven programme/project management as well as the importance of identifying the stakeholders' level of involvement and contribution throughout the process, and manage their expectations.
Design/methodology/approach
The methodology used is based on an action research approach, combining findings from a literature review and case studies within UK's primary healthcare sector.
Findings
Findings demonstrate development of a Benefits Realisation (BeReal) approach in healthcare through looking at case studies taking place within UK's primary and acute healthcare sector.
Research limitations/implications
The framework development is based on theoretical evidence and further research is needed to test and validate its robustness.
Originality/value
The paper highlights the application of benefits realisation and management in developing and delivering primary healthcare facilities.
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Servet Bayindir and Murat Ustaoglu
Religious scripts strongly encourage acts of philantrophy and benevolence that contribute to achievement of social harmony and similarly condemn interest out of money. The views…
Abstract
Purpose
Religious scripts strongly encourage acts of philantrophy and benevolence that contribute to achievement of social harmony and similarly condemn interest out of money. The views paying attention to economic reasons fail to offer a plausible counter argument to this contradiction. Almost all studies since the inception of Islam have, rather than considering the dynamic social and economic realities of the time, attempted to justify the views on the ban. Thus, this study aims to provide clear aspect on Abrahamic religion’s approach on the issue.
Design/methodology/approach
This paper seeks to analyze how the Abrahamic religions approach the issue of interest. For the sake chronology, the Judaic approach will be first analyzed, referring to the main arguments that served as basis for the lift of the ban. Subsequent to the rational arguments raised in the Christian tradition that justified the ban, the reasons for the removal of the ban that changed the attitude of the church will be examined. Finally, based on its original sources, the approach of Islam will be evaluated and the current popular arguments will be discussed.
Findings
A review of the interest issue in the Abrahamic religions in a historical context reveals that there are visible similarities between the arguments that served as basis of the discussions. Christian scholars were able to justify the ban with reference to strong arguments; however, in reference to the conditions that the economy arguably dictated, the ban has been gradually lifted. A similar process has taken place among Islamic scholars as well. Those who adopt an economic perspective fail to consider the chief principles in Abrahamic religions that promote the practice of benevolence.
Originality/value
This paper seeks to analyze how the Abrahamic religions approach the issue of interest from a broader perspective. To this end, the authors offer a general framework of the notion of interest and present the approaches of Abrahamic religions to the concept through reference to popular arguments.
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Yankun Tang, Ming Zhang, Kedong Chen, Sher Ali Nawaz, Hairong Wang, Jiuhong Wang and Xianqing Tian
Detecting O2 gas in a confined space at room temperature is particularly important to monitor the work process of precision equipment. This study aims to propose a miniaturized…
Abstract
Purpose
Detecting O2 gas in a confined space at room temperature is particularly important to monitor the work process of precision equipment. This study aims to propose a miniaturized, low-cost, mass-scale produced O2 sensor operating around 30°C.
Design/methodology/approach
The O2 sensor based on lanthanum fluoride (LaF3) solid electrolyte thin film was developed using MEMS technology. The principle of the sensor was a galvanic cell H2O, O2, Pt | LaF3 | Sn, SnF2 |, in which the Sn film was prepared by magnetron sputtering, and the LaF3 film was prepared by thermal resistance evaporation.
Findings
Through pretreatments, the sensor’s response signal to 40% oxygen concentration was enhanced from 1.9 mV to 46.0 mV at 30°C and 97.0% RH. Tests at temperatures from 30°C to 50°C and humidity from 32.4% RH to 97.0% RH indicated that the output electromotive force (EMF) has a linear relationship with the logarithm of the oxygen concentration. The sensitivity of the sensor increases with an increase in both humidity and temperature in the couple mode, and the EMF of the sensor follows well with the Nernst equation at different temperatures and humidity.
Practical implications
This research could be applied to monitor the oxygen concentration below 25% in confined spaces at room temperature safely without a power supply.
Originality/value
The relationship between temperature and humidity coupling and the response of the sensor was obtained. The nano-film material was integrated with the MEMS process. It is expected to be practically applied in the future.
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K.C. Roy and C.A. Tisdell
This paper examines the importance of property rights in women’s empowerment in rural India. Arguments justifying the need for granting property rights to women are presented and…
Abstract
This paper examines the importance of property rights in women’s empowerment in rural India. Arguments justifying the need for granting property rights to women are presented and the distinction is made between legal (formal) and customary (informal) rights. The ineffectiveness of legal right in absence of customary rights has been discussed. Customary rights also become ineffective due to other institutional impediments. These impediments have been discussed. The results of extensive field work in rural West Bengal and Orissa have been presented to illustrate the pattern of development process that poor rural women want and in which the property right is only one component, not the only component.
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