Hybrid GA-TOPSIS framework for multi-objective optimization of sustainable materials for green building construction

One of the biggest consumers of cement is the construction sector, which contributes significantly to overall carbon emissions and embodied energy around the globe. Conventional selection of concrete materials is typically based on trial and error, which does not adequately address the conflicting objectives of mechanical performance, durability, and environmental sustainability. This led to an urgent demand for systematic, data-driven approaches that ensure both structural reliability and a reduced ecological footprint in green building construction. This study addresses this challenge by developing a tool for sustainable material assessment and optimization of the material selection in this aspect, combining 13 variables of material composition and 13 indicators of concrete performance. This study achieves this by integrating high material evaluation, algorithm-based optimization, and multi-criteria decision making to create a replicable and scalable model for designing sustainable concrete mixes. Using data analytics and nature-inspired algorithm, such as the Genetic Algorithm (GA), this study optimizes concrete performance by adding of sustainable materials or supplementary cementitious materials (SCMs). The GA algorithm effectively identifies MIX_009 containing 38 kg/m 3 , 8 kg/ m 3 , 15 kg/ m 3 , 10 kg/ m 3 , 5 kg/ m 3 of fly ash, silica fume, metakaolin, rice husk ash and alccofine as sustainable materials can achieve a remarkable saving in embodied CO 2 (approximately 257.59 kg/m 3 ) and embodied energy (~ 1545 MJ/m 3 ) as optimal mix with best fitness values of − 0.3605. In addition, the TOPSIS also confirmed the strength of the GA output, ranking MIX_009 as the best with a closeness coefficient of 0.810, affirming it as the most balanced option in terms of performance and sustainability. The findings guarantee that green building materials can be developed with both scientific rigour and practical applicability, addressing urgent sustainability challenges in the construction sector.