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Article
Publication date: 1 April 2002

FUAD MRAD, M. ASEM ABDUL‐MALAK, SALAH SADEK and ZIAD KHUDR

Robotic industrial applications are very well established in the manufacturing industry, while they are relatively in their infancy phase in the construction sector. The need for…

Abstract

Robotic industrial applications are very well established in the manufacturing industry, while they are relatively in their infancy phase in the construction sector. The need for automation in construction is clear especially in repetitive tasks. The excavation process, which is generally critical in most construction projects, is a prime example of such tasks. This paper addresses automation assistance in excavation. The work utilized the robotics approach towards the automation of a typical excavator model, whose structure closely resembled that of an industrial manipulator. A simulation package using Matlab was developed using several embedded design and analysis tools. Emulation was also carried out on the RHINO educational robot to confirm the simulation results. The constructed simulation package offered an integrated environment for trajectory design and analysis for an excavator while addressing the constraints related to the excavator structure, safety and stability, and mode of application.

Details

Engineering, Construction and Architectural Management, vol. 9 no. 4
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 13 May 2014

Anghel Cernescu, Liviu Marsavina and Ion Dumitru

The purpose of this paper is to present a methodology for assessing the structural integrity of a tie member from a bucket-wheel excavator, ESRC 470 model, which was in operation…

Abstract

Purpose

The purpose of this paper is to present a methodology for assessing the structural integrity of a tie member from a bucket-wheel excavator, ESRC 470 model, which was in operation for about 20 years. The tie member is made of S355J2N structural steel. Following the period of operation, the occurrence of microcracks which can propagate by fatigue is almost inevitable. It is therefore necessary to analyze the structural integrity and the remaining life of the component analyzed.

Design/methodology/approach

In principle, the assessment methodology is based on three steps: first, the evaluation of mechanical properties of the material component; second, a BEM analysis using FRANC 3D software package to estimate the evolution of the stress intensity factor based on crack length and applied stress; third, risk factor estimation and remaining fatigue life predictions based on failure assessment diagram and fatigue damage tolerance concept.

Findings

Following the evaluation procedure were made predictions of failure risk factor and remaining fatigue life function of crack length and variable stress range, for a high level of confidence.

Originality/value

As results of this analysis was implemented a program for verification and inspection of the tie member for the loading state and development of small cracks during operation.

Details

International Journal of Structural Integrity, vol. 5 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 8 February 2018

David G. Carmichael and Nur Kamaliah Mustaffa

The performance of earthmoving operations, in terms of emissions, production and cost, is dependent on many variables and has been the study of a number of publications. Such…

Abstract

Purpose

The performance of earthmoving operations, in terms of emissions, production and cost, is dependent on many variables and has been the study of a number of publications. Such publications look at typical operation design and management, without establishing what the penalties or bonuses might be for non-standard, but still observed, practices. To fill this gap in knowledge, this paper examines alternative loading policies of zero waiting-time loading, fractional loading and double-sided loading, and compares the performance of these with standard single-sided loading.

Design/methodology/approach

Original recursive relationships, that are amenable to Monte Carlo simulation, are derived. Case study data are used to illustrate the emissions, production and cost penalties or bonuses.

Findings

Double-sided loading contributes the least impact to the environment and is the most cost effective. Zero waiting-time loading performs the worst in terms of environmental impact and cost. Minimizing truck waiting times through using fractional loading is generally not an attractive policy because it leads to an increase in unit emissions and unit costs. The consequences of adopting fractional loading are detailed. Optimum unit emissions and optimum unit cost are coincident with respect to fleet size for single- and double-sided loading policies. That is, by minimizing unit cost, as in traditional practice, then least impact on the environment is obtained. Not minimizing unit cost will lead to unnecessary emissions.

Practical implications

The results of this paper will be of interest to those designing and managing earthmoving operations.

Originality/value

All modeling and results presented in the paper do not exist elsewhere in the literature.

Details

Construction Innovation, vol. 18 no. 2
Type: Research Article
ISSN: 1471-4175

Keywords

Article
Publication date: 12 November 2018

Aleksandra Tomašević, Ranka Stanković, Miloš Utvić, Ivan Obradović and Božo Kolonja

This paper aims to develop a system, which would enable efficient management and exploitation of documentation in electronic form, related to mining projects, with information…

Abstract

Purpose

This paper aims to develop a system, which would enable efficient management and exploitation of documentation in electronic form, related to mining projects, with information retrieval and information extraction (IE) features, using various language resources and natural language processing.

Design/methodology/approach

The system is designed to integrate textual, lexical, semantic and terminological resources, enabling advanced document search and extraction of information. These resources are integrated with a set of Web services and applications, for different user profiles and use-cases.

Findings

The use of the system is illustrated by examples demonstrating keyword search supported by Web query expansion services, search based on regular expressions, corpus search based on local grammars, followed by extraction of information based on this search and finally, search with lexical masks using domain and semantic markers.

Originality/value

The presented system is the first software solution for implementation of human language technology in management of documentation from the mining engineering domain, but it is also applicable to other engineering and non-engineering domains. The system is independent of the type of alphabet (Cyrillic and Latin), which makes it applicable to other languages of the Balkan region related to Serbian, and its support for morphological dictionaries can be applied in most morphologically complex languages, such as Slavic languages. Significant search improvements and the efficiency of IE are based on semantic networks and terminology dictionaries, with the support of local grammars.

Details

The Electronic Library, vol. 36 no. 6
Type: Research Article
ISSN: 0264-0473

Keywords

Article
Publication date: 13 July 2015

Gary D. Holt and David Edwards

Excavator productivity calculations embrace myriad variables, which in turn, can be modelled in several ways. A key productivity variable is operator competence (O

Abstract

Purpose

Excavator productivity calculations embrace myriad variables, which in turn, can be modelled in several ways. A key productivity variable is operator competence (O c ) because this can impact on so many of the other variables. Earlier research has studied excavator productivity, but little has attempted to simultaneously model productivity variables in relation to O c . The purpose of this paper is to address the void in extant literature.

Design/methodology/approach

A numeric, theoretical analysis is undertaken using the Caterpillar® hydraulic excavator productivity model to estimate excavator production, given: first, variance in modifying factors based on derived maximum and minimum values; and second, variance resulting from linear calculations based on excavator operator competence.

Findings

Excavator productivity resulting from incremental variance of modifying factors in isolation is shown to be linear except, in the case of bucket payload. Simultaneous application of modifying variables results in a greater, curvilinear productivity trend; while it is demonstrated that quantification of key modifying factors can to a significant extent be related to operator competence.

Research limitations/implications

Findings add to productivity literature generally and to that of plant and equipment more specifically. Results will help productivity estimation of excavation in a practical sense while informing subsequent design of an empirical academic research of this problem.

Originality/value

Originality relates principally to determining modifying factor ranges and their analysis of simultaneous effect on each other, especially, as influenced on assumptions of operator competence.

Details

International Journal of Productivity and Performance Management, vol. 64 no. 6
Type: Research Article
ISSN: 1741-0401

Keywords

Article
Publication date: 9 February 2015

Mayukh Sarkar, Subrata Kumar Ghosh and P.S. Mukherjee

The purpose of this paper is to explore the wear phenomena on the bottom surface of an excavator bucket and optimize the design parameters to reduce wear rate by converting…

Abstract

Purpose

The purpose of this paper is to explore the wear phenomena on the bottom surface of an excavator bucket and optimize the design parameters to reduce wear rate by converting sliding motion to rolling motion of rock during the time of operation.

Design/methodology/approach

A test rig has been developed to study the wear phenomena and type of wear on the excavator bucket. Three different bottom plates have been fabricated for experiments to observe the difference of severity of wear in terms of volume of material removal.

Findings

It has been observed that the bottom plate having the mesh-type wear bar pattern was comparatively more resistive to wear than the other two models. Wear-affected zone on the bottom plate was also detected and represented with the help of colour contour.

Practical implications

It is expected that these findings will contribute towards the development of the bottom plate of the excavator bucket with some new pattern of a wear bar, which will be efficient to reduce the phenomena on its surface.

Originality/value

The excavator is one of the important equipment in coal mining. A proper design of the excavator bucket will reduce the wear, as well as the running cost of equipment, and increase the rate of production.

Details

Industrial Lubrication and Tribology, vol. 67 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 24 May 2013

Apif M. Hajji and Phil Lewis

This paper aims to present the framework for a model that can be used to estimate the production rate, activity duration, total fuel use, and total pollutants emissions from…

Abstract

Purpose

This paper aims to present the framework for a model that can be used to estimate the production rate, activity duration, total fuel use, and total pollutants emissions from earthwork activities. A case study and sensitivity analysis for an excavator performing excavations are presented.

Design/methodology/approach

The tool is developed by combining the multiple linear regressions (MLR) approach for modeling the productivity with the EPA's NONROAD model. The excavator data were selected to build the productivity model, and emission factors of all type of pollutants from NONROAD model were used to estimate the total fuel use and emissions.

Findings

Results indicate that the excavator productivity model had high precision and accuracy, low bias, with trench depth and bucket size are in the model, it can explain 92 per cent variability of productivity rate data, and can be used as the basis for estimating the fuel quantities that will be required and the total expected pollutant emissions for the project.

Practical implications

The estimating tool proposed in this paper will be an effective means for assessing the fuel consumptions and air emissions of earthwork activities and will allow equipment owners or fleet managers, policy makers, and project stakeholders to evaluate their construction projects. The tool will help the contractors to estimate the fuel quantities and pollutant emissions, which would be valuable information for a preliminary environmental assessment of the project.

Originality/value

Although there are already methods and models for estimating productivity rate and emissions for heavy duty diesel (HDD) construction equipment, there currently is not a means for doing all of these at once.

Details

Smart and Sustainable Built Environment, vol. 2 no. 1
Type: Research Article
ISSN: 2046-6099

Keywords

Article
Publication date: 3 July 2009

David J. Edwards and Gary D. Holt

The extensive use of mini‐excavators in construction presents a significant health and safety risk from their tendency to become unstable, or in the extreme to roll‐over, under…

Abstract

Purpose

The extensive use of mini‐excavators in construction presents a significant health and safety risk from their tendency to become unstable, or in the extreme to roll‐over, under certain working conditions. No standard exists to specifically assess excavator stability, so the purpose of this paper is to document the development and trial of a series of practical field tests designed to achieve this.

Design/methodology/approach

Tests were designed in collaboration with a group of plant experts and competent operators. The tests were subsequently trialled by applying them to four mini‐excavators, the aim being to see if these plant items could be reliably assessed in terms of their stability characteristics. Results of the study were presented to H&S experts for comment.

Findings

The tests were able to assess mini‐excavator stability. For each machine, five “stability criteria” were scored thereby producing an overall score, by which mini‐excavator stability could be conveniently represented.

Research implications

No previous field test research has been identified in this area. The results produced here may go some way towards developing an international standard for on‐site stability tests.

Practical implications

The tests are easy to apply at the work site so long as performed by competent persons under appropriately risk‐assessed and risk controlled conditions; and if disseminated to industry, could act as a means of standardising mini‐excavator stability tests until such time an International Standard becomes available.

Originality/value

Research in this area is entirely novel.

Details

Engineering, Construction and Architectural Management, vol. 16 no. 4
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 2 September 2013

Helen Lingard, Tracy Cooke and Ehsan Gharaie

The paper analyses the nature and causes of fatal incidents involving excavators occurring in the Australian construction industry. A three-level incident causation model…

1574

Abstract

Purpose

The paper analyses the nature and causes of fatal incidents involving excavators occurring in the Australian construction industry. A three-level incident causation model developed by researchers at Loughborough University forms the theoretical framework for this analysis, which seeks to identify immediate circumstances, shaping factors and originating influences in selected incidents.

Design/methodology/approach

Case study incidents were identified from the National Coronial Information System database. These incidents were subjected to content analysis to identify causal factors.

Findings

Ten cases were analysed in total. In all of these cases immediate circumstances could be identified. These included the use of unsafe work methods and the condition, suitability or useability of plant. In several cases shaping factors, such as communication between work-team members and the design of work processes, were identified as likely contributors to the incidents. In none of the cases could originating influences be identified.

Research limitations/implications

The research was limited by the relatively small number of cases for which detailed investigation reports were available and the fact that, for the most part, the reports focused on the immediate circumstances surrounding the incidents.

Practical implications

The circumstances of the fatal incidents in Australia are similar to those reported in the UK and the USA and the identified causes have known safety solutions. The persistence of these incidents in the Australian construction industry suggests that there may be underlying reasons why known safety solutions are not implemented. Further in-depth analysis of incident causes may help to identify organisational and/or cultural causes of incidents involving excavators.

Originality/value

The analysis provides a more detailed qualitative analysis of the causes of fatal incidents involving excavators than would is possible using national compensation data, which restricts analysis to a classification of the mechanism and agency of injury.

Details

Engineering, Construction and Architectural Management, vol. 20 no. 5
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 4 July 2008

David J. Edwards and Gary D. Holt

In striving to minimise downtime and optimise the productivity of construction excavators, very often, they employ a “quick‐hitch” (Qh) as a means of changing attachments (like…

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Abstract

Purpose

In striving to minimise downtime and optimise the productivity of construction excavators, very often, they employ a “quick‐hitch” (Qh) as a means of changing attachments (like buckets) more quickly. Health and safety issues can relate to Qh use. The purpose of this paper is to observe these health and safety issues and consider their implications for stakeholders.

Design/methodology/approach

Triangulation, embracing a literature review; case studies; and the researchers' experiential knowledge, is employed to examine the nature and prevalence of Qh health and safety incidents.

Findings

It is confirmed that significant risks are associated with (inappropriate) Qh use, especially relating to “manual” and “semi‐automatic” types. The main causes of Qh incidents are observed to be due to workers' acts or omissions, particularly, failure to properly implement safety mechanisms.

Practical implications

An identified emphasis on “people” and their actions, suggest a need for changes in construction working methods and management practice, as ways to help remove Qh risks. Accordingly, proffered solutions relate predominantly to improved worker training, combined with stricter site management. Mechanical solutions may involve possible changes to Qh design.

Originality/value

This specific area of academic plant management study is novel.

Details

Engineering, Construction and Architectural Management, vol. 15 no. 4
Type: Research Article
ISSN: 0969-9988

Keywords

1 – 10 of 89