Civil and Environmental Engineering - Journal articles
Permanent URI for this collection
Browse
Recent Submissions
Item Stability analysis of tunnel face considering the shape of excavation and reinforcement measures(Taylor & Francis, 2024-08-14) Jiang, Yin; Tong, Yueping; Ouyang, Aohui; Ye, Fei; Liu, Chang; Han, Xingbo; Peng, Wenbo; National Natural Science Foundation of ChinaIn mountain tunnels, a series of advanced reinforcement measures are often employed to maintain the stability of the tunnel face, particularly in challenging geological conditions. However, there is a lack of design theories regarding the advanced support structure for uniquely shaped tunnel faces, necessitating further exploration. Based on the limit equilibrium method, this paper presents a derivation of the mechanical model for analyzing excavation face stability considering shape changes and bolts. Additionally, a design theory for horizontal glass fiber bolts in longitudinally inclined tunnel faces is established. The reinforcement effect of the pipe shed is further considered. Finally, the proposed model is validated, and parameter analysis is conducted to guide design practices.Item Real-time condition assessment of a painted megalithic cave using Wireless Sensor Network(Elsevier, 2022-11-22) Wang, Chao; Tavares, Alice; Fonseca, Jorge; Soares, Filipe; Li, Zili; Science Foundation Ireland; European Cooperation in Science and Technology; Universidade de Aveiro; Transport Infrastructure Ireland; Regional Operational Programme CentroThe deterioration of underground heritage caves caused by visitations has attracted extensive attention over the recent decades. Most previous research focused on investigating the impact of visitors on the microclimatic conditions of the interior of large show caves, but much less relevant effort was made for small confined caves, for example, megalithic burial dolmen caves. In addition to environmental condition issues, the structural performance of underground heritage caves also deteriorates in the long-term subject to both natural hazards (e.g. creep in geo-materials and extreme weather) and manmade ones (e.g. construction activities). To this end, a real-time Wireless Sensor Network (WSN) system is deployed inside an underground megalithic dolmen to monitor its structural performance with time so as to assess its long-term structural stability. Meanwhile, the WSN system together with other field sensors and inspection monitors the interior environmental change caused by human visitation effect, aiming to reveal the mechanism behind visitor-caused rock painting deterioration in the small confined dolmen chamber. Results show that structurally, the dolmen can be regarded as generally stable despite a progressive development of structural performance during the first 1.5 months and accidental instability of the near-opening pillar A. In terms of environmental condition, the presence of visitors leads to significant changes of interior microclimatic conditions frequently inside the confined cave against consistent rock painting conservation. Particularly, the cave paintings may deteriorate critically with time as visitation induces a ‘hotbed’ environment for interactions between microorganisms and microstructures of the rock paintings due to the variations of interior microclimate. To ensure long-term structural stability and restore acceptable level of interior microclimate, tinted hydraulic lime and steel rod/brace were recommended for enhancing structural robustness and a mechanical ventilation system for improving environmental resilience of the dolmen. A generalized monitoring approach was proposed for the reference of other similar caves.Item A systematic review of the lived experiences of the energy vulnerable: Where are the research gaps?(Elsevier Ltd., 2024-05-10) Hihetah, Claudia; Ó Gallachóir , Brian; Dunphy , Niall P.; Harris, Clodagh; Science Foundation IrelandThe transition to a low-carbon world, coupled with energy supply uncertainties, has heightened the urgency to better understand the experiences of vulnerable groups who lack affordable and adequate energy. Access to energy is crucial for their health, well-being, and social stability. However, there are significant knowledge gaps relating to the lived experiences of energy vulnerable groups that this paper directly addresses. There is a wide body of literature focusing on the quantification of, and policy response to, energy poverty alongside a fast- growing area of research on the lived experience of the energy vulnerable. This paper's systematic review of research on the lived experiences of the energy vulnerable reveals 46 peer-reviewed articles published between 2011 and 2021. Its review highlights diverse approaches to exploring energy vulnerability, the range of vulnerable groups investigated and different motivations for focusing on lived experiences. The results point to a number of key gaps in the literature in terms of definitions and terminologies, geographic coverage, gender, life stage (specifically children), ethnicity (ethnic minorities absent) and ability (people with disabilities are a further gap). It concludes that there is a need for more context-specific, mixed-methods and longitudinal studies in this area. Having identified gaps in the literature, it recommends how some of these can be addressed and reflects on how studies focused on the lived experience of energy poverty should advance.Item Monitoring and assessment of a cross-passage twin tunnel long-term performance using wireless sensor network(Canadian Science Publishing, 2023-06-22) Wang, Chao; Friedman, Miles; Li, Zili; Science Foundation Ireland; Transport Infrastructure Ireland; National Natural Science Foundation of ChinaThe monitoring and assessment of ageing underground tunnels is critical to ensure their serviceability, stability, and safety as arteries for a transport network in the long term. This paper first comprehensively reviewed the long-term tunnel performance monitoring case studies, aimed at highlighting the limited field monitoring data and identifying research gaps. It was found that previous studies largely focused on the performance of single tunnel sections subject to short-term disturbances (e.g., adjacent excavation), whereas limited efforts concentrated on the long-term performance of twin tunnels, let alone those with cross passages, under the influence of deteriorations. To this end, a Wireless Sensor Network (WSN) was deployed at a critical vehicle cross passage (VCP) twin tunnel section of Dublin Port Tunnel to monitor its long-term ageing performance with time, in addition to the existing long-term water leakage and lining crack monitoring. The evolvement of lining crack and water leakage since 2010 indicated the progressive deteriorations of the monitoring section, and the deployed WSN monitoring of lining inclination demonstrated a robust sensor deployment layout and monitoring plan for (quasi) real-time monitoring for a confined underground cross passage twin tunnel network. An analytical solution was proposed to convert tunnel inclination to horizontal deformation, with the converted measurements suggesting that even more than one decade after construction, both twin tunnels are still moving horizontally towards the VCP centreline in the long term, primarily due to twin tunnel interaction. Along tunnel longitudinal direction, the closer to the VCP, the greater tunnel deformation rate is, revealing the effect of cross passage on tunnel differential longitudinal behaviour, in agreement with hypotheses and numerical results in previous studies. The field observations were believed to be attributed to the two mechanisms which are hydro-geological degradation of the surrounding ground and hydro-mechanical deterioration of the tunnel, where the correlation between tunnel deformation and deteriorations was detailed.Item Tidal stream energy potential in the Shannon Estuary(Elsevier Ltd., 2021-12-18) Fouz, D. M.; Carballo, R.; López, I.; Iglesias, Gregorio; European Regional Development Fund; Xunta de GaliciaThe tidal and river in-stream energy resource in the Shannon Estuary (W Ireland) is investigated using of high-resolution numerical modelling and spatial analysis. Although freshwater discharges are large, their influence on the available resource is found to be all but negligible, the tide being the main driver of estuarine circulation. The Tidal Stream Exploitability (TSE) index is adapted to the analysis of estuaries with non-depth-limited areas (TSEndl), such as the Shannon Estuary, and then used to select the hotspots with potential for a tidal stream farm. For this purpose, a new depth penalty-limiting function is defined to avoid overestimating the available energy potential in areas with depths greater than those required for tidal energy converter operation. Seven hotspots are identified based on the revised index. The approach followed in this study illustrates the applicability of high-resolution numerical modelling and spatial analysis for identifying the most appropriate areas for tidal stream energy conversion. Finally, the potential of tidal stream energy to contribute to the much-needed decarbonisation of the energy mix in Ireland is emphasized.