A Case Study of Building Information Modelling Enabled ‘Information Totem’ for Operations and Maintenance Integration

This paper reports upon the use of a semi-automated toolkit to aid the development of as-built Building Information Model (BIM) (As-built model reflects on-site changes by the contractor to the original BIM) from inception to final construction. An observational case study of two educational ‘multi-storey’ facilities obtained primary data from project archives and focus group meetings with key design team members. The results demonstrate that the data requirements for both structures evolve post occupation because of stakeholder tacit knowledge accrued via building operation and usage. The semi-automated toolkit developed can readily access operations and maintenance (O&M) manuals, retrieve room specific data (such as categories of equipment or building element) within the as-built BIM and, assist in the navigation and coordination of amendments and changes throughout the construction phase. This paper provides useful practice-based information for practitioners to develop suitable BIM data structures for future information requirements throughout a building’s lifecycle. The inherent value of the semi-automated toolkit resides in the facilitation of ease of handover for the Facilities Management team during the O&M stages

Risk of excavators overturning: determining horizontal centrifugal force when slewing freely suspended loads

Purpose: Tracked hydraulic excavators are versatile and ubiquitous items of off-highway plant and machinery that are utilised throughout the construction industry. Each year a significant number of excavators overturn whilst conducting a lifting operation, causing damage to property, personnel injury or even fatality. The reasons for the overturn are myriad, including: operational or environmental conditions; machine operator acts or omissions; and/ or inadequate site supervision. Furthermore, the safe working load (SWL) figure obtained from manufacturer guidance and utilised in lift plans is based upon undertaking a static load only. This research seeks to determine whether the SWL is still safe to be used in a lift plan when slewing a freely suspended (dynamic) load, and if not, whether this may be a further contributory factor to overturn incidents. Approach: Previous research has developed a number of machine stability test regimes but these were largely subjective, impractical to replicate and failed to accurately measure the ‘dynamic’ horizontal centrifugal force resulting from slewing the load. This research contributes towards resolving the stability problem by critically evaluating existing governing standards and legislation, investigating case studies of excavator overturn and simulating the dynamic effects of an excavator when slewing a freely suspended load at high rotations per minute (rpm). To achieve this, both the static load and horizontal centrifugal force from slewing this load were calculated for six randomly selected cases of an excavator, with different arm geometry configurations. Findings: The results from the six cases are presented and a worked example of one is detailed to demonstrate how the results were derived. The findings reveal that the SWL quoted on an excavator’s lift rating chart considerably underestimates the extra forces experienced by the machine when an additional dynamic load is added to the static load whilst lifting and slewing a freely suspended load. Originality: This work presents the first attempt to accurately model excavator stability by taking consideration of the dynamic forces caused by slewing a freely suspended load and will lead to changes in the way that industry develops and manages lift plans. Future research proposes to: vary the weight of load, arm geometry and rpm to predict machine stability characteristics under various operational conditions; and exploit this modelling data to populate pre-programmed sensor based technology to monitor stability in real time and automatically restrict lift mode operations

Desiging an efficient tidal turbine blade through Bio-mimicry: A systemic review

Purpose: A comprehensive literature review is conducted in the tidal energy physics, the ocean environment, hydrodynamics of horizontal axis tidal turbines, and bio-mimicry. Design/methodology/approach: The paper provides an insight of the tidal turbine blade design and need for renewable energy sources to generate electricity through clean energy sources and less CO2 emission. The ocean environment along with hydrodynamic design principles of a horizontal axis tidal turbine blade are described, including theoretical maximum efficiency, Blade Element Momentum theory, and non-dimensional forces acting on tidal turbine blades. Findings: This review gives an overview of fish locomotion identifying the attributes of the swimming like lift based thrust propulsion, the locomotion driving factors: dorsal fins, caudal fins in propulsion, which enable the fish to be efficient even at low tidal velocities. Originality/ value: Finally, after understanding the phenomenon of caudal fin propulsion and its relationship with tidal turbine blade hydrodynamics; this review focuses on the implications of bio-mimicking a curved caudal fin to design an efficient Horizontal Axis Tidal Turbine

Exploring the Significant Cash Flow Factors Influencing Building Projects Profitability in Ghana

This paper identifies and explore significant quantifiable cash flow factors influencing building projects profitability in Ghana. A thorough literature was undertaken to unravel the quantifiable cash flow factors which facilitated design of questionnaire. A survey with prime focus on large firms registered with the Association of Building and Civil Engineering Contractors, Ghana was undertaken. A total of 50 questionnaires were received from 63 administered representing 79.36% response rate with a Cronbach Alpha value of 0.895 and Kappa value of 0.743 respectively were attained. One-sample t-test was performed on the rated responses to establish 12 significant factors. Principal component analysis was subsequently employed to reduce factors to the most significant components. Prominent variables selected from rotated and component score matrixes were: wages of labour and staff; progress payment duration; bank interest rate; and replacement of defective works as significant variables. This study was limited to quantifiable cash flow factors and large construction firms hence, recommended further study with focus on qualitative factors, procurement types, broader scope of construction firms and other developing countries. The outcome of this is to aid construction managers effectively manage the significant cash flow factors to maximize profit

Cyber threats confronting the digital built environment: Common data environment vulnerabilities and block chain deterrence

Purpose Smart cities provide fully integrated and networked connectivity between virtual/digital assets and physical building/infrastructure assets to form digital economies. However, industrial espionage, cyber-crime and deplorable politically driven cyber-interventions threaten to disrupt and/or physically damage the critical infrastructure that supports national wealth generation and preserves the health, safety and welfare of the populous. The purpose of this paper is to present a comprehensive review of cyber-threats confronting critical infrastructure asset management reliant upon a common data environment to augment building information modelling (BIM) implementation. Design/methodology/approach An interpretivist, methodological approach to reviewing pertinent literature (that contained elements of positivism) was adopted. The ensuing mixed methods analysis: reports upon case studies of cyber-physical attacks; reveals distinct categories of hackers; identifies and reports upon the various motivations for the perpetrators/actors; and explains the varied reconnaissance techniques adopted. Findings The paper concludes with direction for future research work and a recommendation to utilize innovative block chain technology as a potential risk mitigation measure for digital built environment vulnerabilities. Originality/value While cyber security and digitization of the built environment have been widely covered within the extant literature in isolation, scant research has hitherto conducted an holistic review of the perceived threats, deterrence applications and future developments in a digitized Architecture, Engineering, Construction and Operations (AECO) sector. This review presents concise and lucid reference guidance that will intellectually challenge, and better inform, both practitioners and researchers in the AECO field of enquiry

Surface Polymer Network Model and Effective Membrane Curvature Elasticity

A microscopic model of a surface polymer network - membrane system is introduced, with contact polymer surface interactions that can be either repulsive or attractive and sliplinks of functionality four randomly distributed over the supporting membrane surface anchoring the polymers to it. For the supporting surface perturbed from a planar configuration and a small relative number of surface sliplinks, we investigate an expansion of the free energy in terms of the local curvatures of the surface and the surface density of sliplinks, obtained through the application of the Balian - Bloch - Duplantier multiple surface scattering method. As a result, the dependence of the curvature elastic modulus, the Gaussian modulus as well as of the spontaneous curvature of the "dressed" membrane, ~{\sl i.e.} polymer network plus membrane matrix, is obtained on the mean polymer bulk end to end separation and the surface density of sliplinks.Comment: 15 pages with one included compressed uuencoded figure

Exploratory investigation of challenges and expectations of innovative quantity surveyors and quantity surveying firms in Ghana

Likeother professions that wish to remain competitive, the quantity surveying profession (QSP) will always find ways to improve its output and systems. Despite the QSPs progress in process innovation, the profession still faces some challenges and is overwhelmed by expectations that must be addressed to improve service. The purpose of this study is to identify the expectations and challenges of quantity surveyors and the QSP. Using an in-depth literature review and quantitative research approach, questionnaires were developed and administered to innovative quantity surveying (QS) firms in Ghana. After validating variables and checking the reliability of the scale, data analysis was carried out using descriptive statistics, cross-tabulation, and a relative importance index (RII). Findings showed that the quantity surveyors expect elimination of corruption from the industry and a high standard of transparency and accountability. The surveyors also desired enhance their skills to remain competitive and be more entrepreneurial and proactive. This study creates awareness for top managers and leaders in QS firms to identify and adopt innovative solutions to address the challenges of the industry and the expectations of individual quantity surveyors. Managing the expectations of quantity surveyors and the challenges of the QSP would help the QS industry remain competitive and lucrative. This paper makes an original contribution to the field by describing the challenges the QSP faces in the construction industry and providing theoretical views on the expectations of innovators

Modelling a conceptual framework of technology transfer process in construction projects: an empirical approach

Technology transfer (TT) is crucial to social infrastructure and economic development in developing countries (DCs). In Ghana’s construction sector, foreign firms provide an invaluable source of innovation and technological advancement for local contractors. However, TT models published in existing literature are rarely applicable to the construction industry in DCs. This paper therefore presents a conceptual framework of the TT process as a tool for measuring construction performance. Utilising the results from a questionnaire survey of Ghanaian construction industry professionals, eight different perspectives on TT were formulated using exploratory factor analysis. These perspectives represent the enablers and outcomes of the TT process, namely transferor and transferee characteristics, knowledge advancement, the transfer environment, government influence, the learning environment, project performance, communication, and relationship building and absorptive capability. The research outcomes provide useful guidance to local and international funding agencies, governments of developing or newly industrialised countries, and construction firms that seek to effectively evaluate the success (or otherwise) of the TT process. Future research should seek to validate the research findings presented, and to expand the work to include other DCs

Design study of a horizontal axis tidal turbine blade

Purpose: A design study was conducted to understand the implications of bio-mimicking a curved caudal fin type horizontal axis tidal turbine blade design, using NACA 0018 is presented. Design/methodology/approach: A method of transforming the traditional horizontal axis tidal turbine by defining a third order polynomial centre line on which the symmetrical airfoils were stationed is also disclosed. Each of the airfoil characteristics: twist angle distribution, chord lengths, and centre line passing through the airfoil centres were automatically transformed to create the curved caudal fin-shaped blade; translating the spinal blade axis into percentage wise chord lengths, using NACA 0018 airfoil. A 3D mesh independency study of a straight blade horizontal axis tidal turbine modelled using Computational Fluid Dynamics (CFD) was carried out. The grid convergence study was produced by employing two turbulence models, the standard k-ε model and Shear Stress Transport (SST) in ANSYS CFX. Findings: Three parameters were investigated: mesh resolution, turbulence model, and power coefficient in the initial CFD, analysis. It was found that the mesh resolution and the turbulence model affect the power coefficient results. The power coefficients obtained from the standard k-ε model are 15% to 20% lower than the accuracy of the SST model. Further analysis was performed on both the designed blades using ANSYS CFX and SST turbulence model. The results between the straight blade designed according to literature and the caudal fin blade showed a maximum power coefficient of 0.4028%, and 0.5073% respectively for 2.5m/s inlet velocity. Originality/ value: An original caudal fin based tidal turbine blade geometry characterised with symmetrical airfoil distribution, which produces higher efficiency throughout the year i.e. even for the lower tidal flow velocities which occur during the winter months, is presented

Innovate to compete: an empirical assessment of measures to enhance innovation adoption in Ghanaian quantity surveying firms

Innovation in construction services is a source of competitive advantage; thus, firms are constantly innovating new ways of working and producing new productsin order tostay in competion. Regardless of this immeasurable benefitof innovation, the Ghanaian quantity surveying (QS) firms are very sluggish in adopting innovation. Also, there is a paucity of research work that will enable QS firms to maximize innovation adoption. This study was conducted to identifyand examinemeasures to enhance innovation adoption in Ghanaian QS firms. Quantitativeapproach and census sampling techniquewere employed in the study. The dependent variables retrieved from 24 out of 43 questionnaires administered to QS firms in Accra and Kumasi were analysed using mean score and Kendall’s coefficient of concordance test. The study concluded that leadership, information and communication technology, supportive work environment, education and training policy, collaboration with partners, and organisational resources are the mostsignificant measures to enhancinginnovation adoption in Ghanaian QS firms. It is recommended thatQS firmsconstantly put into practice large spectraof new ideas in rendering services in order not to be out of competition. This study could serve asbasis for management invarious QS firms in drawing up policies to enhance innovation adoption. Also, QS firms in other developing countries particularly those in sub-Saharan Africawhere thechallenges impeding innovation are likely to be similar can also benefit from the findings. Future research could be focusedon identifying the key attributes and managing the expectations of innovation champions in the QS firms