Dominic Ek Leong Ong

Recent advances in digital technologies have expanded the potential for lifecycle-based assessment in construction. However, their integration into coherent and operational workflows remains limited. While the use of Building Information Modelling (BIM), Digital Twin (DT) and Life Cycle Assessment (LCA) are increasingly common, there are often implemented in fragmented and isolates processes, constraining data-driven decision support.,Extending the prior work of Liew et al. [1], this study presents an empirical analysis examining how professional roles, organisational structures, and digital maturity influence technology adoption in practice. The results reveal a misalignment between digital capability and real-world implementation.,To address this gap, a novel Digital Twin-enabled framework integrating BIM, Internet of Things (IoT) data, and sustainability assessment is proposed. This study provides both empirical evidence and enables continuous data exchange with system integration across lifecycle stages. It contributes a scalable digital construction approach aligned with automated and integrated construction workflows.

In 2022, the International Civil Aviation Organization (ICAO) introduced the Aircraft Classification Rating – Pavement Classification Rating (ACR-PCR) system, replacing the globally adopted Aircraft Classification Number – Pavement Classification Number (ACN-PCN) system for airfield pavement rating. This paper examines the performance of airfield rigid pavements using Federal Aviation Administration methodologies, analysing two airports with rigid pavements as case studies in the published literature. The study compares results from the ACR-PCR and ACN-PCN methods across 36 types of aircraft. The ACN and ACR values of various aircraft were calculated using different subgrade categories. For a single rigid pavement layer, varying thickness was considered to determine the PCN and PCR values. The results reveal that the ACN-PCN method produces more moderate outcomes than the ACR-PCR method. In addition, rigid pavement thickness significantly influences PCN values compared with PCR. These findings can assist airport administrators in preparing for the transition from the ACN-PCN system to the ACR-PCR system.

Civil and geotechnical researchers are searching for economical alternatives to replace traditional soil stabilizers such as cement, which have negative impacts on the environment. Chitosan biopolymer has shown its capacity to efficiently minimize soil erosion, reduce hydraulic conductivity, and adsorb heavy metals in soil that is contaminated. This research used unconfined compression strength (UCS) to investigate the impact of chitosan content, long-term strength assessment, acid concentration, and temperature on the improvement of soil strength. Static triaxial testing was employed to evaluate the shear strength of the treated soil. Overall, the goal was to identify the optimum values for the mentioned variables so that the highest potential for chitosan-treated soil can be obtained and applied in future research as well as large-scale applications in geotechnical engineering. The UCS results show that chitosan increased soil strength over time and at high temperatures. Depending on the soil type, a curing temperature between 45 to 65 °C can be considered optimal. Chitosan biopolymer is not soluble in water, and an acid solution is needed to dissolve the biopolymer. Different ranges of acid solution were investigated to find the appropriate amount. The strength of the treated soil increased when the acid concentration reached its optimal level, which is 0.5–1%. A detailed chemical model was developed to express how acid concentration and temperature affect the properties of the biopolymer-treated soil. The SEM examination findings demonstrate that chitosan efficiently covered the soil particles and filled the void spaces. The soil was strengthened by the formation of hydrogen bonds and electrostatic interactions with the soil particles.

Microbial-induced carbonate precipitation (MICP) is a promising bioremediation technology for heavy metal immobilisation. This review explores the applications and efficacy of MICP in environmental challenges. It provides a comprehensive overview of the mechanism, primarily through ureolysis, detailing the process from urea hydrolysis to heavy metal precipitation as carbonate minerals. Alternative pathways such as photosynthesis and nitrate reduction are also discussed, highlighting the broad applicability of MICP. The review covers the historical evolution and advancements of MICP as a sustainable solution for heavy metal contamination. Recent studies demonstrate the efficiency of MICP in achieving high removal rates in diverse environments. The sustainable operation, precise targeting of heavy metal species, and versatility of MICP are examined. Challenges such as high copper concentrations, acidic conditions, and cost considerations are addressed. The article provides future directions and solutions to these challenges, including leveraging machine learning for optimal performance and enhancing cost considerations through detailed analyses. This review improves understanding of MICP’s potential, provides a valuable resource for researchers in environmental engineering and the built environment, and encourages innovative approaches within these fields.

Characterisation of highly fractured and weathered rock masses within the young Tuang Formation in Sarawak, Malaysia is challenging, mainly due to the difficulties in extracting intact samples for conventional rock testing. Pressuremeter test was used as a viable alternative since it is performed in-situ, hence eliminating the need for sample extraction. A methodology was developed to interpret pressuremeter test results in highly fractured and weathered phyllite using an analytical approach, from which useful strength and stiffness parameters can be obtained. The interpretation method was based on the fundamental theory of cylindrical cavity expansion, which was originally established for soils. The results of the interpretation were in terms of commonly known Mohr–Coulomb strength parameters, which were subsequently used for assessment of frictional pipe jacking forces through back-analysis method. The results of the back-analysis showed the reliability of the developed methodology in analysing pressuremeter test results within highly fractured and weathered phyllite.

Microbially induced carbonate precipitation (MICP) is extensively used for soil stabilisation, sand erosion control, bioremediation and concrete repair. However, detailed bibliometric studies on MICP are scarce, particularly regarding industrial feedstocks, such as urea for ureolytic bacteria and calcium chloride, and the associated ammonia gas production, which poses challenges for large-scale applications. This study reviews 857 articles from the Scopus database (2000–2024), using the VOSviewer software to visualise data on publications, citations, authors, countries, journals, trending keywords and research topics. Significant global collaboration is evident, led by China and the USA. The most cited papers discuss ureolytic microorganisms enhancing soil properties, the basic MICP process, reducing concrete damage, improving soil and groundwater systems and the impacts of MICP on urea hydrolysis and ammonia production. Key terms such as ‘calcium carbonate’, ‘ammonia’ and ‘Sporosarcina pasteurii’ are central to MICP research. Co-occurrence analysis highlights thematic clusters such as microbial cementation and geological features, emphasising the multidisciplinary role of MICP in tackling environmental problems. This review highlights the need to mitigate environmental impacts, particularly those of ammonia production and energy use, in ureolytic MICP. Life-cycle assessments reveal that while ureolytic MICP reduces carbon dioxide emissions, it often consumes more energy, necessitating alternative nutrient sources and cost-effective practices for large-scale applications.