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Compressive strength prediction and optimization design of sustainable concrete based on squirrel search algorithm-extreme gradient boosting technique

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Frontiers of Structural and Civil Engineering 2023年第9期17卷 1310-1325页

作者： Enming LI Ning ZHANG Bin XI Jian ZHOU Xiaofeng GAO ETSI Minas y Energía Universidad Politécnica de MadridMadrid 28003Spain Leibniz Institute of Ecological Urban and Regional Development(IOER) Dresden 01217Germany Department of Civil and Environmental Engineering Politecnico Di MilanoMilano 20133Italy School of Resources and Safety Engineering Central South UniversityChangsha 410083China Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment(Ministry of Education) College of Environment and EcologyChongqing UniversityChongqing 400045China

concrete is the most commonly used construction material.However,its production leads to high carbon dioxide(CO_(2))emissions and energy consumption.Therefore,developing waste-substitutable concrete components is necessary.Improving the sustainability and greenness of concrete is the focus of this research.In this regard,899 data points were collected from existing studies where cement,slag,fly ash,superplasticizer,coarse aggregate,and fine aggregate were considered potential influential factors.The complex relationship between influential factors and concrete compressive strength makes the prediction and estimation of compressive strength difficult.Instead of the traditional compressive strength test,this study combines five novel metaheuristic algorithms with extreme gradient boosting(XGB)to predict the compressive strength of green concrete based on fly ash and blast furnace slag.The intelligent prediction models were assessed using the root mean square error(RMSE),coefficient of determination(R^(2)),mean absolute error(MAE),and variance accounted for(VAF).The results indicated that the squirrel search algorithm-extreme gradient boosting(SSA-XGB)yielded the best overall prediction performance with R^(2) values of 0.9930 and 0.9576,VAF values of 99.30 and 95.79,MAE values of 0.52 and 2.50,RMSE of 1.34 and 3.31 for the training and testing sets,respectively.The remaining five prediction methods yield promising results.Therefore,the developed hybrid XGB model can be introduced as an accurate and fast technique for the performance prediction of green concrete.Finally,the developed SSA-XGB considered the effects of all the input factors on the compressive strength.The ability of the model to predict the performance of concrete with unknown proportions can play a significant role in accelerating the development and application of sustainable concrete and furthering a sustainable economy.

关键词： sustainable concrete fly ash slay extreme gradient boosting technique squirrel search algorithm parametric analysis

Mechanical Properties and Durability of sustainable concrete Manufactured Using Ceramic Waste:A Review

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Journal of Renewable Materials 2023年第2期11卷 937-974页

作者： Peng Zhang Peishuo Zhang Jingjiang Wu Zhenhui Guo Yong Zhang Yuanxun Zheng School of Water Conservancy Engineering Zhengzhou UniversityZhengzhou450001China Communications Construction Company of CSCEC 7th Division Co. Ltd.Zhengzhou450004China

Green and sustainable concrete has attracted significant attention from the construction industry and researchers since it was proposed.The ceramic waste materials are often directly buried in the ground or placed in an open dump,and the accumulation of ceramic waste contributes to environmental pollution,which makes the recycling of ceramic waste quite urgent.Owing to the pozzolanic activity,excellent mechanical properties and durability,industrial ceramic waste is considered as a suitable substitute for cement or natural aggregates to fabricate renewable concrete.In this paper,the pozzolanic activity of ceramic waste and the workability,mechanical performance,and durability of ceramic concrete are discussed.In addition,the most recent research results pertaining to ceramic concrete are reviewed.Ground ceramic powder improves the workability,compressive strength,resistance to chloride penetration,and carbonation resistance of concrete to a certain extent.concrete containing ceramic as the aggregate has a lower mechanical performance than ordinary concrete.However,the resistance to chloride penetration,freeze-thaw resistance,and high-temperature resistance of ceramic concrete are remarkable.Ceramic concrete is environmentally friendly,requires fewer energy resources to manufacture than ordinary concrete,and has excellent engineering properties.However,further research is required for future engineering applications.

关键词： sustainable concrete ceramic waste pozzolanic activity mechanical properties durability

Influence of Recycling Waste Glass as Fine Aggregate on the concrete Properties

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Journal of Renewable Materials 2023年第6期11卷 2925-2940页

作者： Rafal A.Hadi Suhad M.Abd Hadee Mohammed Najm Shaker Qaidi Moutaz Mustafa A.Eldirderi Khaled Mohamed Khedher Department of Civil Engineering Bilad Alrafidain University CollegeDiyala32001Iraq Department of Civil Engineering College of EngineeringUniversity of DiyalaDiyala32001Iraq Department of Civil Engineering Zakir Husain Engineering CollegeAligarh Muslim UniversityAligarh202002India Department of Civil Engineering College of EngineeringUniversity of DuhokDuhok42001Iraq Department of Civil Engineering College of EngineeringNawroz UniversityDuhok42001Iraq Department of Chemical Engineering College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia Department of Civil Engineering College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia Department of Civil Engineering High Institute of Technological StudiesMrezgua University CampusNabeul8000Tunisia

Recent years have witnessed an increase in the quantity of waste glass(WG)across the globe.Replacing the fine aggregate with WG is one of the steps toward preserving the natural resources of the environment and creating low-cost concrete.The present study is concerned with replacing fine aggregates with glass powder(GP)at(0%,15%,30%,and 50%).It has studied the fresh and hardened properties(compressive strength,tensile strength,hardened density,and slump)for all the mentioned percent replacements.The findings have shown that all mixtures containing GP gave acceptable slump results within the design limits(2–5 cm)according to ACI standard 211.1.It has been observed that increasing the proportion of GP led to a decrease in the weight of concrete.Lastly,replacing GP with sand by 30%has led to an increase in the compressive strength by about 2.4%and 12.45%,and the tensile strength by about 2.5%and 26.54%at 7-and 28-d,respectively in comparison to normal concrete.

关键词： sustainable concrete glass powder fine aggregate partial replacement

Effective Contribution of Brazilian Rice Husk Silica(RHS)as Eco-Friendly Silica in concrete Plants

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Journal of Civil Engineering and Architecture 2022年第11期16卷 531-540页

作者： Carlos Marmorato Gomes Antonio de Paulo Peruzzi School of Civil Engineering Architecture and Urban DesignUniversity of CampinasCampinas 13083-970Brazil Faculty of Civil Engineering University Federal of UberlandiaUberlandia 38408-100Brazil

Due to growing consumption of Portland cement and high levels of CO_(2) emissions in its production process,this study examined the use of Brazilian RHS(rice husk silica)obtained by FBC(fluidized bed combustion)as an alternative material in concrete production;the principal cause is the inappropriate disposal of carbonized or in natura rice husk in southern Brazil.To analyze its feasibility,concretes made with several types of cements were examined combined with RHS,and also concretes with different strength classes employing a slag-based binder featuring a smaller amount of clinker in its composition.Mechanical and scanning electron microscopy assays were carried out to verify formation of C-S-H and calcium hydroxide in the cement pastes.This study concludes that replacing 10%of Portland cement(CEMIII/A)by 3%of RHS can result in a cost reduction of around 5%and allows a reduction of 4%in CO_(2)eq levels.In this way,RHS from renewable sources can be a highly impactful sustainable alternative in civil engineering work,allowing the concrete industry to produce environmentally-sound concrete mixtures with lower CO_(2) emissions.

关键词： sustainable concrete eco-friendly silica RHS cement geopolymer