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Article
Publication date: 16 May 2019

Perry John Forsythe and Samad M.E. Sepasgozar

A problematic issue for new approaches to prefabricated timber construction is simply that there is insufficient productivity measurement data to assist estimation of…

Abstract

Purpose

A problematic issue for new approaches to prefabricated timber construction is simply that there is insufficient productivity measurement data to assist estimation of resource usage, speed onsite and best practice. A lack of information potentially results in increased pricing behaviour which may slow the uptake of prefabricated construction. The purpose of this paper is to measure installation productivity onsite for prefabricated timber floor cassette panels and develop sufficient understanding of the process to suggest improved practices.

Design/methodology/approach

A time and motion approach, paired with time-lapse photography was used for detailed capture of prefabricated cassette flooring installation processes onsite. An emphasis was placed on work flow around crane cycles from three case study projects. Time and date stamping from 300 crane cycles was used to generate quantitative data and enable statistical analysis.

Findings

The authors show that crane cycle speed is correlated to productivity including gross and net crane time scenarios. The latter is refined further to differentiate uncontrolled outlying crane cycles from normally distributed data, representing a controlled work process. The results show that the installation productivity rates are between 69.38 and 123.49 m2/crane-hour, based on normally distributed crane cycle times. These rates were 10.8–26.1 per cent higher than the data set inclusive of outlier cycles. Large cassettes also proved to be more productive to place than small.

Originality/value

The contribution of this research is the focus on cranage as the lead resource and the key unit of measure driving installation productivity (in cassette flooring prefabricated construction), as distinct from past research that focuses on labour and craft-based studies. It provides a different perspective around mechanisation, for resourcing and planning of work flow. Crane cycles provide a relatively easy yet reliably repeatable means for predicting productivity. The time-lapse photographic analysis offers a high degree of detail, accuracy and objectivity not apparent in other productivity studies which serves to enable quantitative benchmarking with other projects.

Details

Engineering, Construction and Architectural Management, vol. 26 no. 4
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 1 July 2014

Aviad Shapira, Sagi Filin and Amit Wicnudel

– This study aims to show how laser scanning data can be utilised to quantitatively assess “blind lifts” with respect to their rate and spatial distribution.

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Abstract

Purpose

This study aims to show how laser scanning data can be utilised to quantitatively assess “blind lifts” with respect to their rate and spatial distribution.

Design/methodology/approach

This study employed time study of crane cycles for quantitative measuring of the crane’s work periods in dead areas and mapping the crane operator’s field of view and developing a model that allows the spatial analysis of blind lifts.

Findings

This study found a discrete geometric laser scan-based model that is capable of locating and quantifying the visible and invisible zones from the crane operator’s cabin; 28 per cent of the analyzed crane’s work area represented by the model were found to be invisible, which corresponds fairly to 35 per cent of the half-cycles measured manually that were found to involve blind lifting; the range of blind lifts duration derived from the spatial information-based model was 50 to 84 per cent, which is in excellent correspondence with the 54 per cent to 82 per cent range obtained from the time unit-based analysis.

Research limitations/implications

The laser-based model and the ensuing analyses are limited to the type of buildings whose envelope can practically be represented by the vertical extrusion of their footprint.

Practical implications

The practical implications of the study are reduction of blind lifts as a factor when selecting the location of the crane and staging areas; more effective preplanning of signallers positioning; and ad hoc consideration of analysed dead space for various lift task-based decision-making during construction.

Originality/value

This study demonstrates the ability to capture the geometric relations that characterise the work scene around the tower crane by harnessing the increasingly available laser technology and correlates the results of the manual observations with those obtained from the laser-based model.

Details

Construction Innovation, vol. 14 no. 3
Type: Research Article
ISSN: 1471-4175

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Article
Publication date: 18 June 2021

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.

Details

Engineering, Construction and Architectural Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 1 April 2021

Alireza Ahmadian Fard Fini, Mojtaba Maghrebi, Perry John Forsythe and Travis Steven Waller

Measuring onsite productivity has been a substance of debate in the construction industry, mainly due to concerns about accuracy, repeatability and unbiasedness. Such…

Abstract

Purpose

Measuring onsite productivity has been a substance of debate in the construction industry, mainly due to concerns about accuracy, repeatability and unbiasedness. Such characteristics are central to demonstrate construction speed that can be achieved through adopting new prefabricated systems. Existing productivity measurement methods, however, cannot cost-effectively provide solid and replicable evidence of prefabrication benefits. This research proposes a low-cost automated method for measuring onsite installation productivity of prefabricated systems.

Design/methodology/approach

Firstly, the captured ultra-wide footages are undistorted by extracting the curvature contours and performing a developed meta-heuristic algorithm to straighten these contours. Then a preprocessing algorithm is developed that could automatically detect and remove the noises caused by vibrations and movements. Because this study aims to accurately measure the productivity the noise free images are double checked in a specific time window to make sure that even a tiny error, which have not been detected in the previous steps, will not been amplified through the process. In the next step, the existing side view provided by the camera is converted to a top view by using a spatial transformation method. Finally, the processed images are compared with the site drawings in order to detect the construction process over time and report the measured productivity.

Findings

The developed algorithms perform nearly real-time productivity computations through exact matching of actual installation process and digital design layout. The accuracy and noninterpretive use of the proposed method is demonstrated in construction of a multistorey cross-laminated timber building.

Originality/value

This study uses footages of an already installed surveillance camera where the camera's features are unknown and then image processing algorithms are deployed to retrieve accurate installation quantities and cycle times. The algorithms are almost generalized and versatile to be adjusted to measure installation productivity of other prefabricated building systems.

Details

Engineering, Construction and Architectural Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 6 April 2020

Deepankar Sinha and Shuvo Roy Chowdhury

Ports are a significant link in a global supply chain and an economic entity that contributes to the country's economy. India has around 200 ports along its coastline of…

Abstract

Purpose

Ports are a significant link in a global supply chain and an economic entity that contributes to the country's economy. India has around 200 ports along its coastline of about 8,000 Km, yet none of them perform at par with many Asian ports. In the Indian port system, cargo throughput and the turnaround time (TAT) of ships calling at ports constitute the most significant performance measures. These performance metrics do not integrate sustainability measures such as emission levels and energy consumed. The draft is a constraint in many ports and ships visit with less than full shipload cargo. The TAT for such vessels may be lower, but the emission per ton of cargo carried is higher compared to a ship with full shipload cargo. Many ports have old or poorly maintained equipment. This state of equipment increases pollution and consumption of energy. In this paper, an attempt has been made to address the issue of undesirable and right outputs simultaneously in an Indian port system. This paper proposes a framework to ensure zero defects in Indian port operations and a port-sustainability-index to measure sustainable services in Indian ports.

Design/methodology/approach

The authors used data envelopment analysis (DEA) to show that all private terminals did not perform efficiently and contradicted the notion of Indian policymakers that privatization will lead to an increase in performance levels. A literature review was carried out to identify the dimensions and factors that affect ports' performance. A case study of a major port in India and expert group discussion was done to ascertain the views of stakeholders on deficiencies in the system. The authors complemented this approach with sentiment analysis of opinions expressed by stakeholders over a while, using SentiStrength analysis software (Thelwell, 2010, 2012). The authors used the combined findings to develop the port-sustainability-index (PSI), identify the research question, and develop an ontology of the port system. The authors use the concepts of ontology-design-pattern (ODP) and logistics-service-map (Glöckner et al., 2014; Glöckner and Ludwig, 2016, 2017), opinion mining (Pang and Lee, 2008) and competency questions (Glöckner and Ludwig, 2017) to develop a port system map followed by the identification of critical elements; and the flows (physical and information flow) that gets disrupted due to defects in the system. The ontology led to the identification of competencies and capabilities a port needs to possess. Based on these identification process competency questions were drawn, and the authors identified the plausible defects that port may encounter. The authors suggested the sustainability metrics for monitoring port performance and policy changes based on the competency questions, defects, and mitigation plans.

Findings

The authors introduced four KPIs, namely, port-sustainability-index (PSI), load factor (lx and ly), draft ratio (dr), and turnaround-time ratio (TATR). The authors suggested significant policy changes for Indian ports. These included –(1) Introduction of virtual arrival (VA) policy, reducing randomness in the system by pre-scheduling arrivals and activities. (2) Redefining economic life of equipment and machinery in terms of expenditure, income and desired levels of output. (3) Pricing port charges based on stakeholders’ ability and willingness to pay. The port needs to declare its productivity levels and frame their charges accordingly. (4) The ports need to frame an output-oriented privatization policy where it specifies the growth of the port. (5) Framing vessel pricing policy where a vessel may pay tax for the use of non-clean fuel or a get discount for bringing higher parcel load. (6) Levy lower port charges for the shipper for transporting cargo by rail and barges. (7) Introduce a differential pricing system where port levies lower charges for export cargo compared to import load.

Research limitations/implications

The research work can be extended to develop a simulation model to carry out policy experimentations concerning the improvement of performance and carry out sustainable operations. Alternatively, researchers may develop a multi-criteria optimization model to determine the best course of action, keeping the objective function as minimization of PSI value.

Practical implications

This paper provides the means to the Indian ports to remain competitive, lower emission levels and energy consumption, and optimize emission per ton of cargo handled in the port.

Social implications

Society significantly benefits from this study as it recommends ways to minimize pollution that has a significant impact on human lives. Besides, the measures suggested in the paper will lower the cost of exports and imports, enhancing the real income of consumers.

Originality/value

The area of sustainable port operations has previously been under-researched in the Indian context. Authors contribute to the sustainable port operation literature by suggesting a port-sustainability-index, a framework to assess the defects in port operation and development of a port-ontology for further research in the area of a port system.

Details

International Journal of Quality & Reliability Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0265-671X

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Article
Publication date: 1 July 1958

MUCH has been written about industrial engineering, especially in regard to American practice, but a good deal of confusion still exists about the whole subject.

Abstract

MUCH has been written about industrial engineering, especially in regard to American practice, but a good deal of confusion still exists about the whole subject.

Details

Work Study, vol. 7 no. 7
Type: Research Article
ISSN: 0043-8022

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Article
Publication date: 1 February 1998

EDIZ ALKOC and FUAT ERBATUR

Computer simulation in construction planning has been the subject of research for the last few decades. The present paper describes simulation models geared toward…

Abstract

Computer simulation in construction planning has been the subject of research for the last few decades. The present paper describes simulation models geared toward improving the productivity of concreting operations. It is primarily concerned with a study of the sensitivity of concreting operations to a set of possible resource combinations. Thirteen models are examined by the two well‐known methods of concreting: (1) crane and bucket; and (2) the pump. Concreting into slabs, beams and columns are considered. The simulation software Micro‐CYCLONE is used for the actual generation of models. Sensitivity parameters considered in resource combinations include the number of truck‐mixers, buckets and labourers in concrete placing crews. The simulation models developed are compared and the results are discussed. The results enable planners to realize how the resource quantities and capacities in one cycle affect the ones in another period for cyclic operations like concreting. It can be concluded that the maximum number of resources, the interaction of work crews caused by work space limitations and the interaction of equipment because of sharing with other activities of the project may bring limitations.

Details

Engineering, Construction and Architectural Management, vol. 5 no. 2
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 14 June 2019

Fabio Sgarbossa, Martina Calzavara and Alessandro Persona

Vertical lift module (VLM) is a parts-to-picker system for order picking of small products, which are stored into two columns of trays served by a lifting crane. A…

Abstract

Purpose

Vertical lift module (VLM) is a parts-to-picker system for order picking of small products, which are stored into two columns of trays served by a lifting crane. A dual-bay VLM order picking (dual-bay VLM-OP) system is a particular solution where the operator works in parallel with the crane, allowing higher throughput performance. The purpose of this paper is to define models for different operating configurations able to improve the total throughput of the dual-bay VLM-OP system.

Design/methodology/approach

Analytical models are developed to estimate the throughput of a dual-bay VLM-OP. A deep evaluation has been carried out, considering different storage assignment policies and the sequencing retrieval of trays.

Findings

A more accurate estimation of the throughput is demonstrated, compared to the application of previous models. Some use guidelines for practitioners and academics are derived from the analysis based on real data.

Originality/value

Differing from previous contributions, these models include the acceleration/deceleration of the crane and the probability of storage and retrieve of each single tray. This permits to apply these models to different storage assignment policies and to suggest when these policies can be profitably applied. They can also model the sequencing retrieval of trays.

Details

Industrial Management & Data Systems, vol. 119 no. 6
Type: Research Article
ISSN: 0263-5577

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Article
Publication date: 6 January 2021

Cristina Toca Pérez and Dayana Bastos Costa

This paper proposes to apply the lean philosophy principle of minimizing or eliminating non-value adding activities combined with 4D building information modeling (BIM…

Abstract

Purpose

This paper proposes to apply the lean philosophy principle of minimizing or eliminating non-value adding activities combined with 4D building information modeling (BIM) simulations to reduce transportation waste in construction production processes.

Design/methodology/approach

This study adopts design science research (DSR) because of its prescriptive character to produce innovative constructions (artifacts) to solve real-world problems. The artifact proposed is a set of constructs for evaluating the utility of 4D BIM simulations for transportation waste reduction. The authors performed two learning cycles using empirical studies in projects A, B and C. The construction process of cast-in-place (CIP) reinforcement concrete (RC) was selected to demonstrate and evaluate 4D BIM's utility. The empirical studies focused on understanding the current transportation waste, collecting actual performance data during job site visits and demonstrating the usage of 4D BIM.

Findings

In the first cycle, 4D BIM successfully allowed users to understand the CIP-RC process's transportation activities, which were modeled. In the second cycle, 4D BIM enabled better decision-making processes concerning the definitions of strategies for placing reusable formworks for CIP concrete walls by planning transportation activities.

Practical implications

In Cycle 2, three different scenarios were simulated to identify the most suitable formwork assembly planning, and the results were compared to the real situations identified during the job site visits. The scenario chosen demonstrated that the 4D BIM simulation yielded an 18.75% cycle time reduction. In addition, the simulation contributed to a decrease in transportation waste that was previously identified.

Originality/value

The original contribution of this paper is the use of 4D BIM simulation for managing non-value adding activities to reduce transportation waste. The utility of 4D BIM for the reduction of those conflicts considered three constructs: (1) the capacity to improve transportation activity efficiency, (2) the capacity to improve construction production efficiency and (3) the capacity to reduce transportation waste consequences.

Details

Engineering, Construction and Architectural Management, vol. 28 no. 8
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 4 September 2019

Junliang He, Hang Yu, Caimao Tan, Wei Yan and Chao Jiang

The development of mega container ships and operational pressures puts forward higher requirements on the operational ability of the container terminal. Accordingly, the…

Abstract

Purpose

The development of mega container ships and operational pressures puts forward higher requirements on the operational ability of the container terminal. Accordingly, the purpose of this paper is to propose an effective method for quay crane (QC) scheduling of multiple hatches vessel considering double-cycling strategy to improve the operation efficiency and reduce the risk of delay.

Design/methodology/approach

A mixed integer programming model, which covers the main operational constraints in a container terminal, is formulated to solve the quay crane scheduling problem (QCSP) with a novel objective.

Findings

A case study is presented and a number of numerical experiments are conducted to validate the effectiveness of the proposed model. Meanwhile, management insights are proposed. The results demonstrate that the proposed method can efficiently solve QCSP in a container terminal, and an interesting finding is that reducing the stack layers on the vessel can improve the operation efficiency of QC.

Originality/value

A new mathematical model is proposed for QC scheduling at the operational level, which considers the constraints of double-cycling strategy, multiple hatches and hatch covers. The proposed model also provides methods to research the QC double-cycling problem considering the balance between energy cost and operation efficiency.

Details

Industrial Management & Data Systems, vol. 120 no. 2
Type: Research Article
ISSN: 0263-5577

Keywords

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