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Optimization of machine learning models for predicting the compressive strength of fiber-reinforced self-compacting concrete

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Frontiers of Structural and civil engineering 2023年第2期17卷 284-305页

作者： Hai-Van Thi MAI May Huu NGUYEN Son Hoang TRINH Hai-Bang LY Civil Engineering Department University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

Fiber-reinforced self-compacting concrete(FRSCC)is a typical construction material,and its compressive strength(CS)is a critical mechanical property that must be adequately *** the machine learning(ML)approach to estimating the CS of FRSCC,the current research gaps include the limitations of samples in databases,the applicability constraints of models owing to limited mixture components,and the possibility of applying recently proposed *** study developed different ML models for predicting the CS of FRSCC to address these *** neural network,random forest,and categorical gradient boosting(CatBoost)models were optimized to derive the best predictive model with the aid of a 10-fold cross-validation technique.A database of 381 samples was created,representing the most significant FRSCC dataset compared with previous studies,and it was used for model *** findings indicated that CatBoost outperformed the other two models with excellent predictive abilities(root mean square error of 2.639 MPa,mean absolute error of 1.669 MPa,and coefficient of determination of 0.986 for the test dataset).Finally,a sensitivity analysis using a partial dependence plot was conducted to obtain a thorough understanding of the effect of each input variable on the predicted CS of *** results showed that the cement content,testing age,and superplasticizer content are the most critical factors affecting the CS.

关键词： compressive strength self-compacting concrete artificial neural network decision tree CatBoost

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Long-term performance: strength and metal encapsulation in alkali-activated iron ore tailings

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environmental Science and Pollution Research 2024年第34期31卷 47071-47083页

作者： Levandoski, William Mateus Kubiaki Ferrazzo, Suéllen Tonatto Piovesan, Maria Alice Bruschi, Giovani Jordi Consoli, Nilo Cesar Korf, Eduardo Pavan Graduate Program in Environmental Science and Technology Universidade Federal da Fronteira Sul RS Erechim99700-970 Brazil Graduate Program in Civil Engineering Universidade Federal Do Rio Grande Do Sul RS Porto Alegre90035-190 Brazil Undergraduate Program in Environmental and Sanitary Engineering Universidade Federal da Fronteira Sul RS Erechim99700-970 Brazil

Understanding the strength behavior and leaching characteristics of mining tailings stabilized with alkali-activated cements in the short, medium, and long term is crucial for the feasibility of material applications. In this context, this study assessed the stabilization/solidification of iron ore tailings (IOT) using alkali-activated binder (AAB) composed of sugarcane bagasse ash and eggshell lime at curing times of 7, 28, 60, 90, 180, and 365 days. Additionally, leaching tests were conducted, along with the examination of possible changes in the chemical and mineralogical composition resulting from exposure to acidic environments. Tests included unconfined compression strength (UCS), leaching, X-ray diffraction, and Fourier-transform infrared spectroscopy for the IOT-AAB mixtures. The highest increase in UCS was observed between 7 and 60 days, reaching 6.47 MPa, with minimal variation thereafter. The AAB-bonded IOT exhibited no metal toxicity over time. Elements Ba, Mn, Pb, and Zn present in IOT and ash were encapsulated in the cemented matrix, with complete encapsulation of all metals observed from 90 days of curing time. The mineralogy of the stabilized/solidified tailings showed no changes resulting from leaching tests. Characteristic bands associated with the presence of N-A-S–H gel were identified in both pre-leaching and post-leaching samples for all curing times analyzed. Exposure to acidic environments altered bands related to carbonate bonds formed in the IOT-AAB mixture. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.

关键词： Lime

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Application of machine learning technique for predicting and evaluating chloride ingress in concrete

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Frontiers of Structural and civil engineering 2022年第9期16卷 1153-1169页

作者： Van Quan TRAN Van Loi GIAP Dinh Phien VU Riya Catherine GEORGE Lanh Si HO Department of Civil Engineering University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

The degradation of concrete structure in the marine environment is often related to chloride-induced corrosion of reinforcement ***,the chloride concentration in concrete is a vital parameter for estimating the corrosion level of reinforcement *** research aims at predicting the chloride content in concrete using three hybrid models of gradient boosting(GB),artificial neural network(ANN),and random forest(RF)in combination with particle swarm optimization(PSO).The input variables for modeling include exposure condition,water/binder ratio(W/B),cement content,silica fume,time exposure,and depth of *** results indicate that three models performed well with high accuracy of prediction(R2⩾0.90).Among three hybrid models,the model using GB_PSO achieved the highest prediction accuracy(R2=0.9551,RMSE=0.0327,and MAE=0.0181).Based on the results of sensitivity analysis using SHapley Additive exPlanation(SHAP)and partial dependence plots 1D(PDP-1D),it was found that the exposure condition and depth of measurement were the two most vital variables affecting the prediction of chloride *** the number of different exposure conditions is larger than two,the exposure significantly impacted the chloride content of concrete because the chloride ion ingress is affected by both chemical and physical *** study provides an insight into the evaluation and prediction of the chloride content of concrete in the marine environment.

关键词： gradient boosting random forest chloride content concrete sensitivity analysis

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A hybrid machine learning model to estimate self-compacting concrete compressive strength

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Frontiers of Structural and civil engineering 2022年第8期16卷 990-1002页

作者： Hai-Bang LY Thuy-Anh NGUYEN Binh Thai PHAM May Huu NGUYEN Civil Engineering Department University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

This study examined the feasibility of using the grey wolf optimizer(GWO)and artificial neural network(ANN)to predict the compressive strength(CS)of self-compacting concrete(SCC).The ANN-GWO model was created using 115 samples from different sources,taking into account nine key SCC *** validation of the proposed model was evaluated via six indices,including correlation coefficient(R),mean squared error,mean absolute error(MAE),IA,Slope,and mean absolute percentage *** addition,the importance of the parameters affecting the CS of SCC was investigated utilizing partial dependence *** results proved that the proposed ANN-GWO algorithm is a reliable predictor for SCC’s *** that,an examination of the parameters impacting the CS of SCC was provided.

关键词： artificial neural network grey wolf optimize algorithm compressive strength self-compacting concrete

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Study of Hybrid Steel Fibers Effects on the Workability and Compressive Properties of Non-proprietary UHPC 3rd

Study of Hybrid Steel Fibers Effects on the Workability and ...

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3rd International Conference on Sustainable civil engineering and Architecture, ICSCEA 2023

作者： Zhang, Ye Ogawa, Yuko Goegre, Riya Catherine Kawai, Kenji Civil and Environmental Engineering Program Graduate School of Advanced Science and Engineering Hiroshima University 1-4-1 Kagamiyama Higashi-Hiroshima Japan

ISBN: (纸本)9789819974337

Non-proprietary ultra-high-performance concrete (UHPC) is renowned for excellent mechanical properties, especially high compressive strength which is generally above 150 MPa. Despite the high compressive strength, the failure mode of non-proprietary UHPC under axial loading is sudden, brittle, and explosive. The undesired compression failure mode is not ideal for structure design and undermines the engineering value of non-proprietary UHPC. This research targets to convert the compression failure mode of non-proprietary UHPC from brittle to ductile with hybrid steel fiber reinforcement and select the most effective reinforcing proportion. In this research, a ground granulated blast-furnace slag (GGBS) based non-proprietary UHPC mix is reinforced with five combinations of two steel fiber types with straight ends. The lengths of the two steel fibers are 6.5 mm and 13 mm. The total volume fraction of steel fibers is 2%. The 28-day compressive strengths and the failure modes of the reinforced samples are compared to select a hybrid steel fiber combination that transforms the failure mode of non-proprietary UHPC and strengthens the compression performance most effectively. The experiment results demonstrate that: (1) with steel fibers presented, non-proprietary UHPC is capable of continuously taking compressive load after matrix cracks;(2) instead of explosive brittle failure mode, fiber reinforced non-proprietary UHPC fails in a ductile behavior under axial compression load and the samples stay in integrity;(3) hybrid steel fiber reinforcement is more effective than single type steel fiber reinforcement in improving the compression performance of non-proprietary UHPC. © 2024, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Compressive strength

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Frost Damage Resistance of Portland Blast-Furnace Slag Cement Concrete Cured Internally by Using Roof-Tile Waste Aggregate 2nd

Frost Damage Resistance of Portland Blast-Furnace Slag Cemen...

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2nd International Conference on Sustainable civil engineering and Architecture, ICSCEA 2021

作者： Kirimoto, Taishi Ogawa, Yuko Kawai, Kenji Civil and Environmental Engineering Program Graduate School of Advanced Science and Engineering Hiroshima University Higashihiroshima City Japan

ISBN: (纸本)9789811933028

The purpose of this study was to clarify the relationship between the internal curing effect of roof-tile waste aggregate and frost damage resistance, and to investigate the effects of the replacement ratio of roof-tile waste aggregate as well as curing conditions on the frost damage resistance of concrete. Five types of concrete using Portland blast-furnace slag cement were prepared with a water-to-cement ratio of 0.50 and different replacement ratios of roof-tile waste coarse aggregate (20% and 50% by volume) and roof-tile waste fine aggregate (23% and 58% by volume). Concrete specimens were cured at 20 °C under sealed condition for 3, 7, or 28 days, and they were subsequently exposed to air at 20 °C and 60%R.H. until the age of 28 days. Then, the tests for resistance of concrete to freezing and thawing were carried out for 300 cycles in water, and the relative dynamic modulus of elasticity as well as the mass loss was assessed at the designated periods. As a result, it was found that sufficient frost damage resistance could be secured when the replacement ratio of roof-tile waste aggregate was approximately 20% by volume, and the improvement in frost damage resistance was observed especially when fine aggregate was replaced. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Slags

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Influence of Superplasticizer on Workability and Early Strength of Fly Ash/Blast Furnace Slag Based Geopolymer Mortar 2nd

Influence of Superplasticizer on Workability and Early Stren...

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2nd International Conference on Sustainable civil engineering and Architecture, ICSCEA 2021

作者： Indriani, Kemala Saludung, Apriany Ogawa, Yuko Kawai, Kenji Civil and Environmental Engineering Program Graduate School of Advanced Science and Engineering Hiroshima University 1-4-1 Kagamiyama Higashihiroshima Japan Department of Civil and Environmental Engineering Graduate School of Engineering Hiroshima University 1-4-1 Kagamiyama Higashihiroshima Japan

ISBN: (纸本)9789811933028

Recent studies have shown the presence of ground granulated blast-furnace slag (GGBS) in fly ash based geopolymer induced denser microstructures and better compressive strength. However, the inclusion of GGBS gives rapid setting time despite its benefit in terms of mechanical properties and could cause difficulty in handling the geopolymer in its application such as troubles with delivery time of fresh mix geopolymer concrete. This study aims to investigate the effect of polycarboxylate based superplasticizer, which is commonly used in Portland cement concrete to improve the workability and achieve appropriate compressive strength, on the fresh properties and early strength of geopolymer mortar. Geopolymer mortar was composed of fly ash and GGBS acting as binder with sodium silicate and 12 M of sodium hydroxide solution as alkaline activator. Alkaline to binder and fly ash/GGBS ratios were kept constant at 0.5 and 1.5, respectively. Superplasticizer was added into alkaline solution before casting at various dosages of 0%, 1%, 2%, 4%, and 8% by the binder mass and all the specimens were cured in two regimes of heat curing and 20ºC curing. The results have shown that the inclusion of superplasticizer maintained the workability over the time and may delay the setting of geopolymer mortar. Moreover, the mixture with 8% superplasticizer had dense microstructure and comparable compressive strength to that without superplasticizer at the age of 7 days. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Compressive strength

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Diagnosis of pathological manifestations in popular housing of COHAB in Caruaru, Pernambuco: a forensic approach

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Journal of Building Pathology and Rehabilitation 2025年第1期10卷 1-17页

作者： Lima Júnior, Humberto Correia da Silva Medeiros, Iálysson Barbosa, Felipe Augusto Almeida de Lima, Douglas Mateus Graduate Program in Civil and Environmental Engineering Technology Center Academic Center of Agreste Federal University of Pernambuco Marielle Franco Avenue Nova Caruaru Pernambuco Caruaru 55014-900 Brazil

The construction of Social Interest Housing through housing programs is a crucial government investment aimed at reducing housing deficits and ensuring housing rights for low-income populations. However, despite driving the growth of the construction industry, historically these constructions have faced pathological manifestations. The term "pathology" in this context refers to defects, non-conformities, and failures in constructions. Thus, this study is aimed at examining the pathological manifestations in social interest housing provided by the Popular Housing Company (COHAB-PE), focusing on popular residences built with subsidies targeted at housing programs in Caruaru, in the rural area of Pernambuco. The study, classified as exploratory and documentary following technical procedures, aims to analyze and identify recurring patterns of structural problems in popular housing. This was carried out through the analysis of 36 residences located in Caruaru, all of residential nature. The results underscore the need to investigate such issues, highlighting anomalies mostly related to construction errors, such as the lack of appropriate structural elements and waterproofing in foundations. The proposed technical solutions aim to ensure residents' safety. The lack of compliance with standards and the recurrence of the same problems over time and across different construction companies indicate a systemic failure in construction methods. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2025.

关键词： Construction flaws Expert reports Social interest housing Structural anomalies Technical solutions

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Applicability of Electrical Resistance Method to Moisture Transfer Measurement in Paste Using Mineral Admixture 2nd

Applicability of Electrical Resistance Method to Moisture Tr...

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2nd International Conference on Sustainable civil engineering and Architecture, ICSCEA 2021

作者： Aoki, Takahiro Ogawa, Yuko Kawai, Kenji Civil and Environmental Engineering Program Graduate School of Advanced Science and Engineering Hiroshima University 1-4-1 Kagamiyama Higashihiroshima Japan

ISBN: (纸本)9789811933028

Concrete is a porous material which has the ability to hold moisture stably inside. Since moisture is closely related to the deterioration of concrete structures, it is important to understand the moisture transfer in concrete in order to maintain the concrete structure appropriately. The electrical resistance method is one of non-destructive methods to investigate the moisture in concrete and the moisture transfer can be assessed with time by using one specimen. However, the electrical resistance may be affected by mineral admixtures in concrete. Although previous studies on the effects of mineral admixtures on the electrical resistance have been conducted, there are still many unclear points. Therefore, the purpose of this study is to assess the applicability of the electrical resistance method to moisture transfer measurement in paste containing mineral admixtures by focusing on the moisture transfer in the drying process. The moisture transfer in the hardened cement paste using fly ash and blast furnace slag with water-to-binder ratios of 0.35 and 0.55 was investigated by the electrical resistance method. Stainless steel rods of 0.9 mm in diameter were placed at an interval of 4 mm in the specimen. The calibration test was also conducted to obtain the relationship between the electrical resistivity and the internal relative humidity of the specimen. The result showed that the specific resistance of the specimen containing mineral admixtures was higher than that of the specimen without mineral admixtures. It was observed that at the drying period of 70 days, the internal relative humidity at a depth of 4 mm from the exposed surface was almost the same as the surrounding relative humidity. It is possible to know the change in the internal relative humidity distribution in the cement paste using mineral admixtures during the drying process by performing the calibration test appropriately. © 2023, The Author(s), under exclusive license to Springer Nature Singapore P

关键词： Concretes

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Effect of Molarity of Potassium Hydroxide Solution on Heat Resistance of Fly Ash-Slag Based Geopolymer 2nd

Effect of Molarity of Potassium Hydroxide Solution on Heat R...

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2nd International Conference on Sustainable civil engineering and Architecture, ICSCEA 2021

作者： Saludung, Apriany Azeyanagi, Takumu Ogawa, Yuko Kawai, Kenji Department of Civil and Environmental Engineering Graduate School of Engineering Hiroshima University 1-4-1 Kagamiyama Higashihiroshima City Japan Civil and Environmental Engineering Program Graduate School of Advanced Science and Engineering Hiroshima University 1-4-1 Kagamiyama Higashihiroshima City Japan

ISBN: (纸本)9789811933028

Designing a building material with high fire resistance is crucial for minimizing the impact of catastrophic fire. Geopolymer, a new type of binder synthesized by the reaction of aluminosilicate sources with an alkaline solution, has been extensively studied as it offers comparable or even high durability when compared to ordinary Portland cement (OPC). The concentration of the alkaline solution is one of the important factors that affect the durability;however, there is very little data on the heat resistance of geopolymer activated with potassium hydroxide. Thus, this study aims to investigate the effect of molarity of potassium hydroxide on the heat resistance of fly ash-slag blended geopolymer paste. The potassium hydroxide (10, 12, and 14 M) and sodium silicate solutions were prepared as activator solutions. The initial heat curing at 70 ºC for 24 h was applied. In addition, an OPC specimen was also prepared for comparison. After curing for 28 days, some specimens were exposed to high temperatures (500, 750, and 950 ºC). The compressive strength of unexposed and exposed geopolymer and OPC paste specimens was measured. The results showed that the increase of molarity of potassium hydroxide solution increased the heat resistance of geopolymer in terms of retained compressive strength. Moreover, the geopolymer specimens could maintain higher compressive strength than that of OPC paste when exposed to high temperatures up to 950 ºC. This is attributed to the mineral composition of geopolymer, which is different from OPC paste, as studied by X-ray diffraction analysis. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Potassium hydroxide

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