Identification of Sustainability factors of Self-Compacting Geopolymer Concrete for precast construction using SEM

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Introduction
As the general public becomes more conscious of the effects of global warming and the diminishing availability of resources, an increasing number of companies are working to find solutions that are both environmentally responsible and efficient in their use of resources.The expansion in the development of various types of infrastructure all over the globe is mostly to blame for the increased demand for concrete.Concrete is used on a scale that encompasses the whole world at a pace that is close to 30 billion metric tonnes annually [2].Cement is the binding ingredient in concrete, yet the manufacturing process for cement is responsible for up to 7% of all anthropogenic emissions [3].The manufacturing of cement clinker results in the emission of about one tonne of carbon dioxide for each tonne of clinker produced [4].The burning of calcium carbonate during the clinker-making process is responsible for the production of sixty percent of the carbon dioxide gas that is generated in the cement kiln [1].The manufacture of cement is one of the factors that leads to the waste of energy and natural resources.In the manufacturing of cement, more than 5% of the total energy utilised in industry is used [5].As a result, the ever-increasing demand for cement and concrete is a significant contribution to the destruction of the environment and the escalation of global warming.New environmental protections have the goals of cutting emissions by 55 percent by the year 2030 and making the globe carbon neutral by the year 2050 [6].There are many different tactics that have been utilised in the past to lessen the negative effects that the building industry has on the surrounding environment.Two examples of these efforts are decreasing the amount of clinker used and/or utilising alternative binders.Examples of these include supersulphated cement, alkali-activated materials and geopolymers, and the partial substitution of ordinary Portland cement (OPC) with supplemental cementitious materials (SCM).Due to the fact that alkali-activated materials (AAM) and/or geopolymers (GP) have the potential to reduce CO2 emissions in comparison to OPC-based binders, there has been a growth in interest in these two types of materials during the last several decades.In order to manufacture these binders, aluminosilicate source material is subjected to a reaction with an alkaline solution [7,8].Numerous experiments [9] have shown that it is possible to produce viable aluminosilicate precursors from natural or synthetic sources, such as wastes from industry, agriculture, or municipal wastes.In order to explore the reactivity of these precursors, researchers [9] used a diverse selection of alkaline solutions in addition to raw materials consisting of aluminosilicate.However, not many research have been done to investigate the effects on the environment and the properties of these binders when they are used to make mortar or concrete.Dontriros et al. [10] conducted research on the physicalmechanical, life-cycle evaluation, and economic feasibility of geopolymer bricks built from palm oil fuel ash and concrete scraps.The researchers determined that the payback time for geopolymer bricks created from these materials was 3.88 years.However, the purpose of the research was limited to investigating the manufacturing of geopolymer pastes for use in bricks; a comparison with a reference sample for life-cycle evaluation was not within the scope of the article [10].The research did not go beyond the scope of its emphasis.The compressive strength of the geopolymers created from a combination of fly ash and metakaolin was the greatest, but the environmental impact of the geopolymers made from a combination of fly ash and slag was the lowest [11].According to the findings of a research that compared the two materials with the same compressive strength [12], using alkaliactivated slag resulted in fewer CO2 emissions than utilising OPC concrete did.[12] The study was conducted to evaluate the environmental effect of the two materials.Another research (13), this one comparing the environmental effect of traditional concrete to that of four alternative concrete recipes with the same compressive strength, found that regular concrete had the greatest impact on the environment.The results indicated that alkali-activated fly ash concrete that used natural aggregate fared the best in terms of its effect on the environment [13], despite the fact that a significant amount of alkaline activator was utilised.In a case study that was quite similar to this one [14], the authors emphasised how crucial it was to allot raw aluminosilicate materials, such as fly ash and slag, when calculating the potential damage to the environment.In alkali-activated materials, the environmental impact of alkaline solutions such as sodium silicate solution was shown to be predominate [15].Not only did alkali-activated concrete manufactured from volcanic ash and blast furnace slag have mechanical qualities that were equivalent to those of OPC concrete, but it also had a decrease in its potential for global warming of 44.7% [16].The findings of the research suggest that greater levels of compressive strength are linked to higher levels of carbon dioxide emissions.When compared to alkali-activated concrete (AAC) created from alkali-activated blast furnace slag, it was proven that alkali-activated concrete (OPC) made from alkali-activated blast furnace slag had much higher compressive strength and lower CO2 emissions [17].Although heat curing, which aims to increase compressive strength in alkali-activated materials, is one such process that could have an impact [18], it is not the only one.Special applications such as alkali-activated masonry blocks exhibited lower embodied carbon and water consumption when compared to compacted stabilised engineered soil & cement blocks with the same mechanical and durability qualities as a conventional concrete block [19].

What is sustainability
To ensure economic, social, environmental, and institutional sustainability throughout their existence, infrastructure projects in both the public and private sectors must be carefully conceived, designed, constructed, operated, and commissioned.Many companies are contributing to resource depletion and environmental degradation.We are doomed to repeat the mistakes of our forebears if we don't change course.Sustainable development, according to the United Nations Brundtland Commission Report, is "that which meets the needs of the present without compromising the ability of future generations to meet their own needs."Everything we need comes from Mother Nature.Today, humans must cohabit with nature to provide these fundamental requirements for future generations.Sustainability promotes innovation without sacrificing quality of life.Weakness in any of its three pillars renders the system unsustainable.Environmental: We responsibly use the planet's resources.Today's infrastructure will affect energy, material, water, and ecosystems for decades.Economic: A firm or owner must utilize resources effectively and ethically while making profit to be economically sustainable.It involves creating long-lasting enterprises and products that benefit society and the bottom line.Social sustainability is a society's capacity to maintain its members' well-being and quality of life.Sustainability considers a product's influence on host and impacted communities, including health, well-being, and equality.The building sector can greatly preserve world population increase by employing procedures that aim for all three pillars.Sustainable materials like precast concrete help construction businesses save energy, material, and labor costs while protecting the environment.

What is Precast Concrete
Precast concrete is concrete that has been manufactured via the processes of casting and curing in a factory.The equipment is sent to the installation location.Since precast concrete is constructed off-site before construction begins, it greatly speeds up the production process.Complex subterranean constructions created from precast building components suggest that precast concrete has been used in the construction business at least as far back as Ancient Rome.It is utilised in the construction of parking garages, bridges, building foundations, whole buildings, culverts, sound barriers, curb inlets, catch basins and more because of its longevity and sustainability.

What Makes Precast Concrete Sustainable
All three of the sustainability criteria may be met using precast concrete.It may be used economically and socially responsibly without harming the environment.
Environmental sustainability: Precast concrete's low water-to-cement ratio makes it durable.Sand, gravel, and cement make concrete.Cement and water create a strong crystalline matrix that combines with sand and gravel to make concrete.Concrete resists corrosion, rot, and natural deterioration from sunshine, moisture, and harsh weather, unlike other building materials.It strengthens if unhydrated cement particles bind with moisture.
Precast concrete can withstand hot and cold temperatures in most regions because to its thermal bulk.By delaying surface heating or cooling, it reduces building energy use.Precast concrete may be made locally using locally available materials, reducing travel emissions.Precast is factory-made utilizing exact-batch technology, so there is minimal waste in the facility or on-site.Precast concrete materials do not drain harmful byproducts into the ground or water.

Economic sustainability:
Reusing precast concrete structures is easy.Due to its strength and longevity, dismantled components are unharmed.Downcycling precast concrete is possible.They may be broken or crushed to make sidewalks, roadways, or concrete slabs.Downcycling is energy-efficient and durable.Precast drainage structures also install quicker.Precast drainage systems are designed products, not installations, hence installation errors are rare.This reduces on-site labor and manufacturing fault and field modification waste.Suppliers typically give discounts on bulk precast concrete components for various products, saving organizations money.
Social sustainability: Precast concrete uses recycled components from other industries.Some include Precast concrete may employ fly ash, slag, and silica fume that would otherwise be dumped.These chemicals decrease landfill and ocean trash and cement use in precast concrete.Concrete materials do not release gases, harmful substances, or volatile organic compounds into drinking water.This prevents "sick building syndrome" in precast concrete buildings for allergy sufferers.Precast concrete plants have less dust, creating a healthy work environment and protecting on-site workers from poor air quality.With wildfires and floods on the increase, we need robust infrastructure.Non-combustible precast concrete.Concrete helps prevent fires from spreading between buildings.Precast concrete barriers protect people and property from wildfires.After the fire, the concrete may be repaired.Concrete may be employed in flood barrier designs since it's waterresistant and won't float away.

The Future of Sustainable Concrete
Eco-friendly building will use sustainable concrete.Precast concrete is durable and energyefficient, promoting environmental sustainability.Reusing and downcycling promotes economic sustainability.Since it's harmless to everything, including drinking water, it makes workplaces safer, promoting social sustainability.Precast concrete constructions endure natural calamities for decades.They need less maintenance and concrete.Because it produces no greenhouse emissions, eliminates the need for landfills, lessens the use of energy and raw materials, and promotes recycling, the concrete sector is well on its way to being carbon neutral by 2050.We are collaborating with those in the cement business to create a carbon-light product.

Sustainability factors of Self-Compacting Geopolymer Concrete for precast construction
1. Energy consumption during production Sustainable Self-Compacting Geopolymer Concrete (SCGC) may generate less energy than regular concrete.SCGC consumes less energy because: SCGC cures at lower temperatures than concrete.Portland cement cures higher than SCGC geopolymer binders.Lower curing temperatures save production energy.SCGC formulations use less cement.SCGC geopolymer binders may reduce Portland cement's energy use.SCGC lowers cement content and concrete embodied energy.Industrial waste: SCGC employs fly ash, blast furnace slag, and cementitious materials.Industrial leftovers are usually discarded.SCGC saves energy and benefits from these materials.SCGC needs less mechanical mixing than concrete.This speeds mixing.SCGC mix optimization decreases manufacturing energy.The correct raw materials decrease processing, mixing, and placement energy.Composition, manufacturing method, and local energy sources save energy in SCGC manufacture.A project-specific LCA or energy assessment may better quantify SCGC's precast construction energy savings.

Water usage during production
SCGC can conserve water during production, as it uses less water-to-binder than regular concrete and geopolymer binders function and strengthen with less water.Self-Compacting: SCGC freely fills the formwork without vibration or compaction, saving manufacturing water.Supplementary cementitious materials: SCGC often employs fly ash, blast furnace slag, and other industrial wastes.Good mixing: SCGC production may use less water using high-speed or planetary mixers, mix designs may minimize water consumption without affecting SCGC performance, reusing SCGC production water reduces water usage, and water management may improve industrial water reuse and reduce water usage.These water-saving strategies may help SCGC minimize precast construction water usage.Project-specific studies may better quantify SCGC's precast construction water savings.

Uses of Concrete compared with In-Situ Concrete
The Self-Compacting Geopolymer Concrete (SCGC) is a precast concrete system that outperforms in-situ concrete in precast construction.Benefits include faster precast assembly, stronger compressive strength, chemical resistance, and lower permeability than Portland cement-based concrete, reduced environmental impact, safety, workability, and flowability, and customization.SCGC components are stronger and more versatile than Portland cement-based concrete, and use fly ash, slag, or silica fume as binders instead of cement, lowering carbon dioxide emissions and increasing waste recycling.SCGC components are stronger and more versatile than Portland cement-based concrete, and use fly ash, slag, or silica fume as binders instead of cement, lowering carbon dioxide emissions and increasing waste recycling.

Environmentally Friendly
Self-Compacting Geopolymer Concrete (SCGC) for precast buildings is environmentally friendly due to its low carbon footprint, energy efficiency, durability, and sustainability.It uses fly ash, slag, and silica fume to make geopolymer binders, recycles industrial waste, and is energy-efficient.It endures, reduces resource use and waste, uses less water to make, and can be crushed for construction aggregate.It is LEED and BREEAM certified, and can improve sustainable building certifications.SCGC's environmental benefits should be weighed against local conditions, project demands, and performance standards.Project stakeholders, material suppliers, and manufacturers must cooperate to use SCGC optimally and sustainably.

Money
Sustainable Self-Compacting Geopolymer Concrete (SCGC) may offer cost-effective precast building options despite initial pricing discrepancies.SCGC costs depend on local market circumstances, raw material availability, project size, and design requirements.SCGC manufacture uses less energy than ordinary concrete owing to lower curing temperatures and cement concentration.SCGC's chemical resistance and decreased cracking may minimize precast element maintenance and repair expenses during their lifetime.Self-compacting SCGC speeds construction and simplifies installation, decreasing labor and construction time.
SCGC's environmental benefits may boost the project's reputation, attract green customers, and open new markets.SCGC costs depend on local market circumstances, raw material availability, project size, and design requirements.When considering SCGC's financial benefits, consider long-term cost savings such less maintenance and greater durability.

Quality
The most important details in this text are the characteristics of Self-Compacting Geopolymer Concrete (SCGC).These characteristics include compressive, tensile, and flexural strength, geopolymer binders, curing, and mix design, durability, self-compacting workability, dimensional stability, bonding, quality control, and sustainability certification.SCGC must be dimensionally stable to maintain precast parts' dimensions, bond to reinforcement to transmit weight, and match precast or coated.Quality control and industry best practices are essential for successful production of SCGC.Testing, quality control, and industry best practices enable precast sustainable Self-Compacting Geopolymer Concrete.

Utilization of Waste Materials
Sustainable Self-Compacting Geopolymer Concrete (SCGC) for precast buildings generated from trash lowers waste, conserves natural resources, and promotes environmental sustainability.SCGC trash includes fly ash from coal-fired power plants, iron and steel industries create slag, silicon metal and ferrosilicon alloy production generates silica fume, rice husk ash, ground granulated blast furnace slag (GGBFS), recycled aggregates from demolished buildings, quarry dust, ceramic waste, and glass powder.These waste items may improve SCGC without landfilling, promote circular economy, and support sustainable development.SCGC must examine and assess these waste materials for product quality and durability.9. Resource Efficiency SCGC precast construction requires resource efficiency, which is achieved by optimizing raw material, energy, and water utilization.Resource-efficiency factors include selection, mix design, precision batching and manufacturing, sorting and recycling industrial and construction waste, energy-efficient SCGC manufacturing, low-energy geopolymer activation, high-intensity mixers, energy management systems, save SCGC manufacturing water, lightweight aggregates or superabsorbent polymers limit water curing, and recycling water.Lean manufacturing and waste management reduce material, packaging, and energy waste, and trash recycling prevents landfills.For resource-efficient SCGC manufacturing, designers, engineers, material suppliers, and manufacturers must interact.

Durability
Sustainable Self-Compacting Precast Geopolymer Concrete (SCGC) must resist diverse conditions, such as longevity, reduced permeability, alkali-silica reaction (ASR), freezethaw damage, wear and degradation, and long-term diversification.SCGC must resist sulfates, chlorides, and alkalis, make it chemically strong, reduce permeability, reduce reinforcement corrosion and freeze-thaw damage, and reduce alkali-silica reaction (ASR).SCGC may reduce alkali-silica reaction (ASR), which causes concrete expansion and cracking.SCGC may freeze-thaw, but low water-to-binder ratios, air-entraining admixtures, and aggregate selection reduce freezing and thawing water expansion damage.SCGC must maintain structural integrity to keep precast pieces sturdy and load-bearing.Quality control, including compressive strength and other mechanical property tests, assures SCGC's durability.SCGC requires designers, engineers, material suppliers, and manufacturers.Sustainable Self-Compacting Geopolymer Concrete (SCGC) is a versatile precast construction material that allows architects and designers to construct shapes, forms, and textures.It is project-specific and mixes it adds strength, durability, color, and finish.SCGC can make walls, beams, columns, slabs, and façade panels.It can also construct bridges, tunnels, retaining walls, drainage systems, retrofitting and rehabilitation, modular building, and modular construction.SCGC's precast construction versatility fosters innovation, efficiency, and sustainability.Designers, engineers, material suppliers, and manufacturers must collaborate to make SCGC adaptable.

Versatility
12. Weather-proof and Fire Resistant SCGC is a sustainable self-compacting weatherproof and fireproof Geopolymer Concrete (SCGC) suitable for precast construction in hostile conditions.It has low permeability, resists UV, chemical, and weathering, and can withstand saltwater, humidity, and high temperatures.It also has minimal thermal expansion and shrinkage, and can be weatherproofed with waterproof coatings or sealants.Moisture protection improves weatherproofing.
Geopolymers are heat-resistant.Lightweight fire-resistant aggregates may increase SCGC's fire resistance.These aggregates are heat-resistant and have low thermal conductivity, increasing SCGC fire performance.SCGC may be fire-tested.SCGC's fire resistance, endurance, and propagation tests may help it fulfill fire safety regulations.SCGC preserves structure integrity during fires.This shields the structure from fire-exposed precast.Geopolymer binders, mix design, aggregate selection, and precast element thickness determine SCGC's fire resistance and weatherproofing.Sustainable Self-Compacting Geopolymer Concrete in precast building must be fire-resistant and weatherproof.

Cost Effective
The most important details in this text are the factors that make durable precast SCGC costeffective.Fly ash and slag reduce cement in SCGC, which costs more than concrete, and it uses less energy than concrete.Binders and mix designs decrease energy, curing, and manufacture, and SCGC's resilience to weathering, chemicals, and other degradation may save maintenance and repair costs.Construction efficiency is improved by self-compaction and off-site precast, and SCGC manufacture using waste cementitious materials reduces trash and disposal expenses.Lifetime Costing (LCCAs) may evaluate SCGC's profitability and compare SCGC's long-term cost.SCGC's cost-effectiveness depends on local materials, transportation, labor, and size, and suppliers, manufacturers, and construction specialists may improve precast construction cost.

High Safety
The most important details in this text are that durable precast SCGC requires safety, is fireproof, resists weathering, chemical assaults, and other deterioration, and requires strict quality control to ensure material and design quality.SCGC's low-permeability and durability save construction upkeep, and its self-compaction speeds and uniformly compacts concrete, avoiding voids and poor bonding.Environmental Health and Safety: SCGC reuses cementitious ingredients and reduces Portland cement use, and must meet safety and building standards.Safe SCGC precast components are regulated locally.Sustainable Self-Compacting Geopolymer Concrete safety requires designer-engineercontractor-stakeholder collaboration.

Design Flexibility
Sustainable Self-Compacting Geopolymer Concrete (SCGC) is a versatile precast material that allows architects and designers to create unique precasts.It is lightweight yet strong, with panels, cladding, and ornamental pieces being lightweight and flexible.It is aestheticizable with pigments or ornamental aggregates, and can be mixed with glass, carbon, or steel reinforcements to improve characteristics or design.SCGC can be mixed with glass, carbon, or steel reinforcements to increase precast element structure and aesthetics.SCGC's modularity allows factory-controlled precast element manufacture, and its precast construction design flexibility enables architectural creativity, multiple design options, and distinctive, sustainable constructions.Collaboration between architects, designers, engineers, and manufacturers increases sustainable Self-Compacting Geopolymer Concrete's design possibilities.

Labor And Neighbor Friendly
The Sustainable Self-Compacting Geopolymer Concrete (SCGC) benefits make precast construction labor-and neighbor-friendly.It reduces installation and compaction labor, compresses easily in complicated molds and formwork, speeds construction, quiets construction, is perfect for regulated industrial precast manufacturing, reduces construction disturbances, emits less dust and pollutants than concrete, uses non-Portland cement binders and cementitious ingredients to reduce greenhouse gas emissions, and helps construction projects show sustainability, which neighbors and stakeholders enjoy.SCGC reduces worker and community disruptions during construction.

Carbon Footprint
Environmental CO2 forms calcium carbonate with alkaline concrete components like calcium hydroxide, which affects precast sustainable Self-Compacting Geopolymer Concrete (SCGC) durability and performance.SCGC's binder lowers CO2 and its geopolymer binders contain less calcium hydroxide, lowering carbonation reaction alkalinity.Alkaline activators make geopolymer gels more stable and carbonation-resistant than hydrated cement paste.Durable SCGC has little carbonation potential and reduces carbonation and reinforcement corrosion.Protective Barrier: SCGC blocks carbon dioxide to minimize carbonation.
Design and oversight: SCGC carbonation depth determines function and coating or sealant required.Life Cycle Assessment: SCGC's low carbonation potential is eco-friendly and reduces concrete deterioration-related CO2 emissions.SCGC manufacturing quality control and long-term durability goals may improve precast carbonation resistance.prevent mold and mildew, reduces moisture absorption and mold and mildew development, and regulates interior temperatures.SCGC uses low-VOC coatings and sealants, and uses eco-friendly coatings to lower indoor air pollution.Precast construction projects employing SCGC must address indoor air quality.

Natural Materials
Sustainable Self-Compacting Geopolymer Concrete (SCGC) manufactured from natural components makes precast structures more sustainable.SCGC uses pozzolanic materials instead of cementitious binders, industrial fly ash and slag, crushed stone or gravel, quarried aggregates stabilize concrete, rice husk ash or silica fume, natural cementitious supplements reduce non-renewable resource consumption, hemp, jute, and sisal may enhance SCGC, and natural bio-based ingredients improve workability, set time, or concrete properties.SCGC may employ recycled aggregates or crushed concrete, which reduces waste and resource use.Natural materials in SCGC may decrease environmental impact, promote sustainability, and reduce dependence on non-renewable resources in precast construction projects.Natural SCGC mix ingredients must be acquired, quality managed, and suitable to maintain precast element performance and lifetime.

Low Maintenance
SCGC is a low-maintenance precast construction component that withstands chloride, sulfate, and alkali-silica.It has low shrinkage and fracture resistance, which reduce precast element cracking.Surface defense is provided by additives or coatings, which resist staining, UV damage, and weathering.SCGC's smooth, compact surface makes cleaning easier than typical concrete, and it resists creep and distortion.Stability requires no structural upkeep, but precast sections require inspections and preventive maintenance.If correctly placed and maintained, Sustainable Self-Compacting Geopolymer Concrete in precast construction requires just periodic cleaning, joint inspection, and quick issue resolution.

Comfortable And Healthy
SCGC can help precast building projects by providing health and comfort advantages such as thermal mass, indoor air quality, moisture control, fire-resistant protection, comfortable aesthetics, sustainable self-compacting geopolymer concrete, ventilation, thermal insulation, and design.SCGC's thermal mass boosts building comfort, heat absorption and storage manage interior temperatures and conserve energy, indoor air quality improves, moisture control prevents mold and mildew growth, robust structure isolates sound, fireresistant protection protects persons, mold-resistant SCGC reduces indoor allergens, comfortable aesthetics, and sustainable self-compacting geopolymer concrete.Ventilation, thermal insulation, and design enhance SCGC comfort and health in the built environment.

Mechanical Properties Concrete
SCGC offers strong mechanical properties for precast construction.It can meet or surpass concrete's compressive strength, resist bending and load-induced cracking, resist perpendicular tensile stresses, and resist chemicals, sulfate, chloride, and alkali-silica.It also resists chemicals, sulfate, chloride, and alkali-silica, and its dense microstructure and low permeability protect precast components from harmful contaminants.Bond Strength: SCGC's strong bond strength between concrete and reinforcement provides load transmission and avoids interface delamination or failure, maintaining precast components' stability and integrity over time.Optimizing these factors and applying quality control throughout manufacture ensures SCGC's precast construction mechanical performance.Industry standards and testing are needed to verify SCGC mechanical properties for specific applications.

Methodology
An online survey was carried out to determine the sustainability characteristics of Self-Compacting Geopolymer Concrete for precast construction.A detailed but simple survey has been created.The questionnaire is divided into two pieces.The first part contains basic information on the respondents, while the second section discusses the sustainability characteristics of Self-Compacting Geopolymer Concrete for precast construction.A Likert scale of 1 to 5 is used to assess the degree of relevance.Responses were submitted by project managers, site engineers, architects, contractors, quantity surveyors, and owners.The survey was sent to a wide range of civil businesses, academic institutions, commercial and public sector organizations, and others.Several of them, however, were unable to answer, while others' replies were unsatisfactory.182 completed survey forms were submitted for review, with 13 incomplete survey forms removed.The findings were reached after taking into account every single answer.The survey was completed by a total of 182 persons.The data was analyzed using Structural Equation Modeling (SEM).The PLS approach is made up of two sets of equations: the assessment model and the structural model.The internal model creates the relationships between the components.Figs. 1, 2, and 3 give the experience, location, and education information of respondents.

Qualification Information
In the current assessment, PLS-SEM was deemed the best technique for investigating the relationship between elements influencing development owing to predetermined reasons.The PLS-SEM model was chosen over other relapse methods because it manages multicollinearity in terms of dependent and free components.The PLS-SEM model is a multivariate approach that evaluates several linked subordinate connections at the same time using factor reduction philosophies and straight relapses.The structural model [15] may estimate all of the route diagram's dependent and independent linked components that define the connection.Causal modeling is a hybrid of regression and route analysis.The equation model outperforms prior PLS-based models in three key ways [16,17].These are their names: • The PLS technique assesses only one construct, whereas covariance-based techniques assess at least four.• The PLS approach handles non-normal survey data very well, and it is ideal for analysing such data.• PLS corrects for measurement errors and accounts for interaction effects.Following the reliability analysis, the assessment of correctness or fineness is utilized to analyze the internal consistency of the study.Cronbach's alpha was calculated to be 0.816.As a consequence, it is more than the standard threshold of 0.7.The reliability is then declared valid and ready for study.Table 1.A thorough list of all impact measurements is available.Finally, it is determined that the survey data is reliable.Fig. 4 shows the SEM Model for Sustainability Factors of Self-Compacting Geopolymer Concrete for Precast Construction.

SEM Model Construction
As a result, the SEM model developed serves as a framework for analyzing research variable interactions.In Table 2, the latent variable coefficient is given.

Model Fit and Quality Indices
1. Average path coefficient (APC) = 0.954 • (An average path coefficient value above 0.90 is considered acceptable and a good fit.) 2. R 2 = 0.938 • The value of R2 is always between 0 and 100%.
• 0% denotes a model that explains no variation in the response variables around its mean.The mean of the dependent variable predicts both the regression model and the dependent variables.• 100% means that the model explains all of the changes in the response variable around its mean.• In general, the higher the R2, the more accurately the regression model matches your data.

Goodness-of-Fit Index
• (GoF)=0.135 • The integrity of fit (GOF) metric is utilised to guarantee that the model sufficiently depicts the experimental information.The GOF values range from 0 to 1, with values of 0.10 (little), 0.25 (medium), and 0.36 (huge), demonstrating that the way the model has been implemented has been approved around the world.A decent model fit demonstrates that a model is both meagre and conceivable.

Skewness and kurtosis
• Skew and kurtosis can be investigated using descriptive statistics.
• When using SEM, the values for skewness and kurtosis that are acceptable are between -3 and -3 [18].

Relative Importance Index
The Statistic Package for Social Science (SPSS) was used to assist with the review, and the responses from the 182 surveys were thoroughly analyzed for further information.The influence of Coronavirus on the development industry was explored, and the variables were prioritized in terms of predicted criticality using the Relative Importance Index (RII), as indicated by condition (2), and the findings are displayed in Table 3.
Where, W stands for "weight," and respondents gave it a number between 1 and 5, with 1 meaning "strongly disagree" and 5 meaning "strongly agree"; the greatest weight (i.e., in this instance, 5), and There were N total respondents.

Feasibility of Factor Analysis Data
Measures of sample adequacy include the Kaiser-Meyer-Olkin (KMO) and the Bartlett's Test, which were used to verify that factor analysis yielded appropriate results.Bartlett's Test of Sphericity also ensures that the survey questionnaire may be generalized for factor analysis and given in table 5. .000 The value of KMO may vary anywhere from 0 to 1. KMO values between 0.8 and 1.0 indicate that appropriate sampling has been performed.Scores on the KMO that fall between 0.7 and 0.79 are regarded to be ordinary, and numbers that fall between 0.6 and 0.69 are considered to be low.KMO readings that are lower than 0.6 indicate that there was inadequate sampling, and thus, remedial action has to be taken.

Conclusion
Sustainable development reduces the consumption of limestone, marlstone, and coal.Geopolymer binder is made from industrial waste, which saves natural virgin components.Geopolymer concrete outperforms OPC concrete in terms of mechanical strength, shrinkage and creep stresses, and durability.The low greenhouse gas emissions, usage of waste resources, and long service life of geopolymer binder concrete contribute to sustainable development.SCGC is a green construction material that reduces air pollution, conserves natural resources, reduces noise pollution, and conserves energy for ambient curing.SCGC, which is formed of GGBFS and RHA, is a cost-effective and safe waste disposal material for industrial and agricultural waste.It eliminates CO2 emissions, conserves natural resources, quiets the environment, and saves oven curing energy.
Geopolymer concrete saves energy and reduces carbon dioxide emissions.It may take years to replace OPC-based concrete in the market.As a result, this paper covers current geopolymer concrete research and incorporates their results on mix compositions, curing temperature, and microstructural features to provide a complete picture of this unique material and its qualities.Eco-friendly geopolymer concrete has the potential to replace traditional concrete in a variety of building areas.Because of its concrete-like construction, it is long-lasting.Geopolymer concrete is used for marine and acid-attacked constructions due to its durability.Geopolymer concrete is long-lasting because to its strong microstructure, which lowers porosity and prevents fluid ingress.Mechanically, geopolymer concrete outperforms OPC concrete.It is used to replace concrete in various structural sections.Aluminosilicates such as fly ash, rise-husk ash, and others were investigated.Geopolymer concrete based on fly ash outperformed.The most effective alkaline activators are sodium hydroxide and sodium silicate.Alkaline solution molarity, percentage, and reactivity were used as geopolymerization criteria.To acquire geopolymer concrete properties, an alkaline activator was suggested.Silicates accelerate geopolymerization more quickly than hydroxide-based activators.Addressing all mix design components enhances the mechanical properties of geopolymer concrete.The activator molarity, concentration, superplasticizer type and dose, aggregate type, sand type and content, water-to-binder ratio, activator-to-binder ratio, and hydroxide-to-silicate ratio are all important.
Questionnaires were utilized to collect information that would be used to help in the actual application of the approach in precast construction.Reduction in Carbon Footprint,Utilization of Waste Materials, Environmentally Friendly, Reduce Water usage during production, Low Maintenance, Augmentation of Mechanical Properties of Concrete, Natural Materials, Cost Effective, Reduction in Energy consumption during production are the nine main factors for Sustainability factors of Self-Compacting Geopolymer Concrete for precast construction using structural equation modeling.

Fig. 4 .
Fig. 4. SEM Model for Sustainability factors of Self-Compacting Geopolymer Concrete for precast construction Table2.Latent Variable coefficient SCGC precast allows precasters to create distinctive architectural components with DesignAdaptabilityoptions. It is self-compacting and can create complex geometries, curves, and patterns.It is mechanically stable and lightweight, providing design adaptability and aesthetic appeal.SCGC can create unique colors and textures, making precasting easier.Modular SCGC can build walls, floors, and facades faster, and can have exposed aggregate, polished, honed, or textured surfaces.SCGC precast adds elegance, sustainability, and durability to a project.
18. Indoor Air Quality Sustainable Self-Compacting Geopolymer Concrete (SCGC) precast buildings may enhance indoor air quality by emitting less VOCs than concrete, reducing off-gassing, and withstanding radon better than concrete.SCGC's low porosity and moisture resistance

Table 1 .
Sustainability factors of Self-Compacting Geopolymer Concrete for precast construction with factor loadings and Cronbach's alpha

Table 3 .
Relative Importance Index for Sustainability factors of Self-Compacting Geopolymer Concrete for precast construction

Table 5 .
KMO and the Bartlett Test