Civil and Environmental Engineering - Conference Items

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    Using model selection and reduction to develop an empirical model to predict energy consumption of a CNC machine
    (Springer Nature Switzerland AG, 2022-10-17) Morris, Liam; Clancy, Rose; Hryshchenko, Andriy; O’Sullivan, Dominic; Bruton, Ken; Margaria, Tiziana; Steffen, Bernhard; Horizon 2020
    With an ever growing need to reduce energy consumption in the manufacturing industry, process users need to become more aware on how production impacts energy consumption. Computer numerically controlled (CNC) machining tools are a common manufacturing apparatus, and they are known to be energy inefficient. This paper describes the development of an empirical energy consumption model of a CNC with the aim of predicting energy consumption based on the number of parts processed by the machine. The model can then be deployed as part of a decision support (DS) platform, aiding process users to reduce consumption and minimise waste. In using the Calibrated Model Method, the data undergoes initial preparation followed by exploratory data analysis and subsequent model development via iteration. During this analysis, relationships between parameters are explored to find which have the most significant on energy consumption. A training set of 191 datapoints yielded a linear correlation coefficient of 0.95, between the power consumption and total units produced. RMSE, MAPE and MBE validation test yielded results of 0.198, 6.4% and 2.66% respectively.
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    The effect of pore water pressure on structural performance of CERN concrete-lined tunnel
    (Civil Engineering Research Association of Ireland, 2020) Xiao, Zhipeng; Osborne, John Andrew; Perez-Duenas, Eliseo; Li, Zili; Ruane, Kieran; Jaksic, Vesna; Horizon 2020
    The European Centre for Nuclear research (CERN) operates the most powerful circular particle accelerator in a large-scale underground tunnel network of over 70 km. Even over four decades after construction, substantial cracks, water infiltration and structural deformation have still been developing with time based upon field observation and measurements. In particular, recent blockage of tunnel drainage system alters the hydraulic boundary condition and results in the development of pore-water pressure around the tunnel circumference, which in turn accelerates the tunnel deterioration and leakage. In this study, the development of pore water pressure and its effect on tunnel lining are investigated using 3D hydro-mechanical coupled finite element modelling. In the numerical simulation, particular emphasis is placed on the change of lining permeability and the drainage system with time. Results show that the pore water pressure on tunnel lining is significantly affected by the change of hydraulic condition, and consequently exacerbates the tunnel structural performance in the long term.
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    Structure design and assessment of a floating foundation for offshore wind turbines
    (American Society of Mechanical Engineers (ASME), 2019-11-03) Ye, Q.; Cheng, S.; Kim, B.; Collins, K.; Iglesias, Gregorio
    This paper summarizes the assessment of the structural analysis and design of a floating foundation for offshore floating wind turbine (FWT) based on DNVGL standard and Eurocode in terms of economy and reliability. The wind loads are calculated using empirical equations. The wave loads are obtained and verified using various methods including hand calculation, AQWA and Flow-3D. It is found that the shell thickness could be reduced significantly by introducing the stiffeners (stringer or ring), which can decrease the weight of the hull and lower the cost. While DNVGL and Eurocode yield similar design solutions if using plane shell structures, Eurocode significantly underestimates the buckling resistance of stiffened cylindrical shells.
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    Automatic UAV inspection of tunnel infrastructure in GPS-denied underground environment
    (Springer Nature Switzerland AG, 2022-06-16) Zhang, Ran; Ouyang, Aohui; Li, Zili
    In the Architecture, Engineering and Construction (AEC) industry, unmanned aerial vehicles (UAV) has been widely acknowledged as a promising tool to perform adaptive structural health monitoring automatically. However, there still remains some challenges for drones to collect image data of underground structures, primarily due to low light and no GPS conditions. In order to facilitate data acquisition, this article developed a mobile software development kit (MSDK) for drone using visual positioning and predefined controlling code, which enabled the drone to automatically fly along a designated sinusoidal route, whilst continuously taking videos and images of the tunnel surface. The developed MSDK was able to adjust the drone parameters (e.g., overlapping rate, inspection range, heading, flight direction between frames of the video) for different underground infrastructure conditions. Furthermore, a field test is conducted in an abandoned windless tunnel near Cork (Goggins Hill Tunnel) to test its feasibility. Results show that the 40-m difference between the designated routine and actual routine was 1.9%, and the collected data processed by Pix4Dmapper could reconstruct the complete tunnel scene and surface details. The navigation method proposed in this paper allows UAVs to perform automatic inspection without GPS, and the collected image data is used to build a tunnel panorama view.
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    Industry 4.0 driven statistical analysis of investment casting process demonstrates the value of digitalisation
    (Elsevier B.V., 2022-03-08) Clancy, Rose; Bruton, Ken; O'Sullivan, Dominic; Keogh, Dermot; Science Foundation Ireland
    The purpose of this research is to perform statistical data analysis of currently manually collected data in an area of the industrial manufacturing organisation employed in this study that is not digitalised to show the value that can be achieved through digitalisation. The insights gained through analysis of the data can be used to drive decision making in relation to the optimisation of input parameters to minimise the level of defective parts. The parts under investigation in this study were ceramic shells used in the manufacturing process of orthopaedic metal implants. The ceramic shell is a crucial element in the investment casting process because molten metal is poured into the ceramic shell to form the shape of the metal orthopaedic implant. Hence, by minimising the number of defective ceramic shells, there are fewer defective metal implants produced, resulting in cost savings and increased efficiency of the manufacturing process. A number of scientific questions to establish the relationship between the quantity of scrapped products and the level of the silica component in the ceramic slurry were defined and a series of independent t-tests were conducted to address these questions. The results from the t-tests showed the statistically optimal percentage of silica in the binder of the ceramic slurry to minimise the rate of a particular scrap type caused by thin or weak areas of the shell. These results demonstrate the value of analysing digital data relating to the manufacturing process to understand relationships between parameters in the manufacturing process and effectively root-cause scrap outputs. The results from the analysis gave rise to the implementation of a digitalised data collection system that allows continuous monitoring of the components in the ceramic slurry to ensure they are in the optimal specified range. Hence, the quality and yield rate of the orthopaedic implants are maintained at a high level. The digital data collection system also acts as a resource containing historical data for further potential scrap root-cause analysis.