A pronounced gap often exists between expected and actual safety performance in the construction industry. The multifaceted causes of this performance gap are resulting from the misalignment between design assumptions and actual construction processes that take place on-site. In general, critical factors are rooted in the lack of interoperability around the building and work-environment information due to its heterogeneous nature. To overcome the interoperability challenge in safety management, this paper represents the development of an ontological model consisting of terms and relationships between these terms, creating a conceptual information model for construction safety management and linking that ontology to IfcOWL. The developed ontology, named Safety and Health Exchange (SHE), comprises eight concepts and their relationships required to identify and manage safety risks in the design and planning stages. The main concepts of the developed ontology are identified based on reviewing accident cases from 165 Reporting of Injuries, Diseases and Dangerous Occurrences Regulations (RIDDOR) and 31 Press Releases from the database of the Health and Safety Executive (HSE) in the United Kingdom. Consequently, a semantic mapping between the developed ontology and IfcOWL (the most popular ontology and schema for interoperability in the AEC sector) is proposed. Then several SPARQL queries were developed and implemented to evaluate the semantic consistency of the developed ontology and the cross-mapping. The proposed ontology and cross-mapping gained recognition for its innovation in utilising OpenBIM and won the BuildingSMART professional research award 2020. This work could facilitate developing a knowledge-based system in the BIM environment to assist designers in addressing health and safety issues during the design and planning phases in the construction sector.

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Uncertainties exist on the efficiency of CO₂ injection and storage in deep unminable coal seems due to potential reduction in the permeability of coal that is induced by CO₂ adsorption into the coal matrix. In addition, there is a limited knowledge about the stability of CO₂ stored in coal due to changes in gas partial pressure caused by potential leakage. This paper presents an experimental study on permeability evolution in a high rank coal from South Wales coalfield due to interaction with different types of gases. The reversibility of the processes and stability of the stored CO₂ in coal are investigated via a series of core flooding experiments in a bespoke triaxial flooding setup. A comprehensive and new set of high-resolution data on the permeability evolution of anthracite coal is presented. The results show a considerable reduction of permeability above 1.5 MPa CO₂ pressure that is correlated with the coal matrix swelling induced by CO₂ adsorption. Notably studied in this work, the chemically-induced strain due to gas sorption into coal, that has been isolated and quantified from the mechanically-induced strain as a result of changes in effective stress conditions. The results of post-CO₂ core flooding tests using helium (He), nitrogen (N₂) and methane (CH₄) demonstrated a degree of restoration of the initial permeability. The injection of N₂ showed no significant changes in the coal permeability and reversibility of matrix swelling. The initial permeability of the coal sample was partially restored after replacing N₂ by CH₄. Observation of permeability evolution indicates that the stored CO₂ has remained stable in coal under the conditions of the experiments.

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The high affinity and adsorption capacity of coal to carbon dioxide provides an alternative approach for the enhanced recovery of methane from unminable coalfields (CO₂-ECBM) by which a potential solution for long-term CO₂ sequestration in deep geological formations can also be achieved. However, due to chemomechanical effects induced by the interactions between CO₂ and coal, the effective methane production and carbon dioxide storage can be degraded which has caused uncertainties about the techno-economic feasibility of the CO₂-ECBM process. This study presents an experimental investigation that aims to address key knowledge gaps related to the efficiency of CO₂ storage and CH₄ recovery in high rank coals for which a comprehensive experimental data set and analysis are largely missing. Competitive displacements of CH₄ with N₂ or CO₂ in an anthracite coal sample from a South Wales coalfield have been studies, based on a series of core flooding experiments. The results show that the N₂ breakthrough time (the time at which 1% of the total gas injected was recovered) was almost spontaneous whereas a considerably delayed breakthrough time was observed for the case of the CO₂-ECBM experiment. In addition it was observed that for the CO₂-ECBM experiment, the ratios of CH₄ recovery with respect to the total amount of gas injected and gas stored were higher by factors of 10 and 2.4, respectively. The results also show that 90% of the total N₂ injected was produced in the outflow gas, whereas for the case of the CO₂ experiment, only 63% of the total injected CO₂ was produced. The presence of a high amount of N₂ in the outflow may lead to additional challenges in order to separate N₂ from CH₄ and thus affect the efficiency of the N₂-ECBM method. Under the conditions of the experiments, the total CH₄ displacement ratio and breakthrough for the case CO₂-ECBM were found to be more favorable compared to those obtained from N₂-ECBM. This study provides new insights into the efficiency of the CO₂-ECBM process and offers a comprehensive experimental data set that can be used for testing the accuracy of predictive models.

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This paper presents the design, development, and application of a laboratory setup for the experimental investigations of gas flow and reactions in a fractured rock. The laboratory facility comprises (i) a high pressure manometric sorption apparatus, where equilibrium and kinetic phenomena of adsorption and desorption can be examined, (ii) a high pressure triaxial core flooding system where the chemical reactive transport properties or processes can be explored, and (iii) an ancillary system including pure and mixed gas supply and analysis units. Underground conditions, in terms of pore pressure, confining pressure, and temperature, can be replicated using the triaxial core flooding system developed for depths up to 2 km. Core flooding experiments can be conducted under a range of gas injection pressures up to 20 MPa and temperatures up to 338 K. Details of the design considerations and the specification for the critical measuring instruments are described. The newly developed laboratory facility has been applied to study the adsorption of N2, CH4, and CO2 relevant to applications in carbon sequestration in coal and enhanced coalbed methane recovery. Under a wide range of pressures, the flow of helium in a core sample was studied and the evolution of absolute permeability at different effective stress conditions has been investigated. A comprehensive set of high resolution data has been produced on anthracite coal samples from the South Wales coalfield, using the developed apparatus. The results of the applications provide improved insight into the high pressure flow and reaction of various gas species in the coal samples from the South Wales coalfield.@en