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Risk identification and management are the two most important parts of construction project management. Better risk management can help in determining the future consequences, but identifying possible risk factors has a direct and indirect impact on the risk management process. In this paper, a risk prediction system based on a cross analytical-machine learning model was developed for construction megaprojects. A total of 63 risk factors pertaining to the cost, time, quality, and scope of the megaproject and primary data were collected from industry experts on a five-point Likert scale. The obtained sample was further processed statistically to generate a significantly large set of features to perform K-means clustering based on high-risk factor and allied sub-risk component identification. Descriptive analysis, followed by the synthetic minority over-sampling technique (SMOTE) and the Wilcoxon rank-sum test was performed to retain the most significant features pertaining to cost, time, quality, and scope. Eventually, unlike classical K-means clustering, a genetic-algorithm-based K-means clustering algorithm (GA–K-means) was applied with dual-objective functions to segment high-risk factors and allied sub-risk components. The proposed model identified different high-risk factors and sub-risk factors, which cumulatively can impact overall performance. Thus, identifying these high-risk factors and corresponding sub-risk components can help stakeholders in achieving project success.

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Disposing electronic plastic waste into construction materials is an eco-friendly and energy efficient solution to protect the environment. This work is aimed at enhancing the strength of self-compacting concrete (SCC) replacing sand with electronic waste, namely, High Impact polystyrene (HIPS) plastic granules and cementitious material with fly ash. SCC is designed with the optimized binder content of 497 kg/m3 using Fly Ash (30% by weight of cement) and 0.36 as water-to-binder ratio for all the mixtures. High Impact Polystyrene granules are replaced with sand up to 40% (by volume) at a regular interval of 10%. Rheological behavior is observed with the slump flow test for slump diameter, V-funnel test for flow time, and the L-box test for heights ratio, respectively. Strength behavior is studied by performing split tensile strength, and compressive strength tests after a period of 7, 28, and 90 days, respectively. Both fly ash and HIPS aggregate in addition to SCC up to 30% exhibits a minimal strength reduction with a promising performance in workability. Hence incorporation of both fly ash and HIPS granules up to 30% in SCC is a viable eco-friendly technique, with the beneficial economic impact on the construction industry.

This investigation is focused on durability studies of binary blended self-compacting concrete (SCC) with the replacement effect of electronic plastic waste, namely high-impact polystyrene (HIPS) granules as partial sand. In the current investigation, for all the SCC mixes, cement is replaced with pozzolanic material fly ash in the binder content of 497 kg/m3 and an adopted water-to-binder ratio of 0.36. Durability properties such as porosity, water absorption, and sorptivity are assessed for the curing periods of 28 and 90 days on SCC specimens produced with HIPS (0%–40% replacement by volume of sand). Both surface and internal water absorption rates were found to be minimal for SCC with HIPS. Replacement of HIPS up to 30% in SCC exhibited improved trends for all tests results. Reported durability parameter values were within permissible limits and revealed the excellent performance of HIPS in SCC. The optimum durability values can be attributed to the dense microstructure of SCC obtained with the combined effect of HIPS and fly ash. The continuous gradation of aggregates in the matrix reduced porosity due to the spherical shape of HIPS; additionally, the hydrophobicity of HIPS inhibits moisture migration in SCC. The additional benefits of fly ash, such as pozzolanic action and the filler effect at the interfacial transition zone (ITZ) are also major contributions to the long-term performance of durability. Electronic plastic waste replacement for fine aggregates in concrete compensates for the disposal problem and conserves natural sand.