Journal of Advanced Concrete Technology最新文献

Multi–sensory Monitoring and Non–destructive Testing of New Materials for Concrete Engineered Barrier Systems 混凝土工程屏障系统新材料的多感官监测和无损检测

IF 2 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-09-06 DOI: 10.3151/jact.22.516

Vera Lay, Franziska Baensch, Anna Maria Skłodowska, Tobias Fritsch, Michael Stamm, Prathik Prabhakara, Sergej Johann, Patrick Sturm, Hans-Carsten Kühne, Ernst Niederleithinger

{"title":"Multi–sensory Monitoring and Non–destructive Testing of New Materials for Concrete Engineered Barrier Systems","authors":"Vera Lay, Franziska Baensch, Anna Maria Skłodowska, Tobias Fritsch, Michael Stamm, Prathik Prabhakara, Sergej Johann, Patrick Sturm, Hans-Carsten Kühne, Ernst Niederleithinger","doi":"10.3151/jact.22.516","DOIUrl":"https://doi.org/10.3151/jact.22.516","url":null,"abstract":"The crucial part of nuclear waste storage is the construction of sealing structures made of reliable, safe and well–understood materials. We present an extended analysis of long-term multi–sensory monitoring and non–destructive testing (NDT) inspection of two laboratory specimens aiming at potential materials for sealing structures for nuclear waste repositories. Specimens with a volume of 340 litres made from newly developed alkali–activated materials (AAM) and established salt concrete (SC) were analysed using embedded acoustic emission and wireless radio-frequency identification (RFID) sensors, ultrasonic echo imaging, active thermography, and X–ray computed tomography. The monitoring analysis showed lower heat of reaction and 50% less acoustic emission events in AAM compared to SC. However, due to the surface effects of the AAM material, the number of acoustic emission events increased significantly after approximately two months of monitoring. Subsequently performed NDT inspections reliably located embedded sensors and confirmed the absence of major cracks or impurities. The presented laboratory results show the feasibility and potential of comprehensive NDT monitoring and inspection to characterise cementitious and alternative materials as well as the need for multi–parameter long–term monitoring. Thus, our study demonstrates that tailored NDT investigations will help to develop safe sealing structures for nuclear waste repositories.\u0000","PeriodicalId":14868,"journal":{"name":"Journal of Advanced Concrete Technology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ion Evolution in Pore Solution of Alkali-activated Slag System and Its Effect on Passivation Behaviour of Steel Bars 碱激活炉渣体系孔隙溶液中的离子演化及其对钢棒钝化行为的影响

IF 2 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-08-27 DOI: 10.3151/jact.22.499

Zhantao Du, Zuquan Jin, Bo Pang, Shicai Li, Chencui Wang

{"title":"Ion Evolution in Pore Solution of Alkali-activated Slag System and Its Effect on Passivation Behaviour of Steel Bars","authors":"Zhantao Du, Zuquan Jin, Bo Pang, Shicai Li, Chencui Wang","doi":"10.3151/jact.22.499","DOIUrl":"https://doi.org/10.3151/jact.22.499","url":null,"abstract":"The passivation of steel bars in concrete is determined by the characteristics of the concrete pore solution. However, ion evolution in the pore solution of alkali-activated slag/limestone powder (AAS/L) systems is not yet well known. Therefore, in this study, ion evolution in real and simulated pore solutions of alkali-activated slag/limestone powder mortars is investigated using high-pressure and solid-liquid extraction methods. The study focuses on investigating the passivation behaviour of steel bars when exposed to the simulated pore solution. The results demonstrate that the contents of Ca, Na, Al, Si, and S2O32- first increase and then decrease with time, whereas the contents of K and SO42- consistently increase. Among the simulated pore solutions, the one with a solid-liquid ratio of 1 : 1 and an age of 14 days closely resembles the actual pore solution. In addition, the presence of a high S content resulting from the dissolution of S in the slag inhibits the passivation process of the steel bars in the simulated pore solution of AAS. However, the passivation film of the steel bars formed in the simulated AASL pore solution is strengthened by the addition of the limestone powder.\u0000","PeriodicalId":14868,"journal":{"name":"Journal of Advanced Concrete Technology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Carbonated Concrete Slurry Waste as Supplementary Cementitious Material 作为补充胶凝材料的碳化混凝土浆废料

IF 2 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-08-23 DOI: 10.3151/jact.22.485

Frank Winnefeld, Johannes Tiefenthaler, Andreas Leemann

{"title":"Carbonated Concrete Slurry Waste as Supplementary Cementitious Material","authors":"Frank Winnefeld, Johannes Tiefenthaler, Andreas Leemann","doi":"10.3151/jact.22.485","DOIUrl":"https://doi.org/10.3151/jact.22.485","url":null,"abstract":"Concrete slurry waste is generated at concrete plants and generally re-used in new batches of concretes. Due to the presence of hydrated cement paste it has the potential to be carbonated prior to re-use in order not only to store CO2, but also to enhance its reactivity in blends with cement. In this study, a concrete slurry waste obtained at a ready-mix concrete plant was investigated. For accelerated carbonation, a wet process was used at laboratory scale. The carbonated product was dried afterwards, characterized and used as supplementary cementitious material. When carbonated, the hydrate phases of the concrete slurry waste decomposed to calcite, gypsum and a silica-alumina gel. When blended with Portland cement (30% replacement by mass) early hydration kinetics was accelerated by the carbonated concrete slurry waste. The pozzolanic reaction of the silica-alumina gel consumed a significant part of the portlandite and showed a slightly positive contribution to compressive strength compared to inert quartz powder and to the uncarbonated concrete slurry. This offers the use of carbonated concrete slurry waste to store CO2 in concrete with the additional benefit of reducing the cement content.\u0000","PeriodicalId":14868,"journal":{"name":"Journal of Advanced Concrete Technology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigating the Influence of SCMs on Mechanical Performance through Experimental Feret's Coefficients in Low-carbon Concrete 通过低碳混凝土中的试验费雷系数研究单体材料对力学性能的影响

IF 2 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-08-23 DOI: 10.3151/jact.22.471

Ana Antunes, Eliana Soldado, Hugo Costa, Ricardo do Carmo, Eduardo Júlio

{"title":"Investigating the Influence of SCMs on Mechanical Performance through Experimental Feret's Coefficients in Low-carbon Concrete","authors":"Ana Antunes, Eliana Soldado, Hugo Costa, Ricardo do Carmo, Eduardo Júlio","doi":"10.3151/jact.22.471","DOIUrl":"https://doi.org/10.3151/jact.22.471","url":null,"abstract":"The focus on sustainable construction materials has prompted research into alternatives to reduce the carbon dioxide emissions associated with the production of Portland cement. Several studies have attempted to minimise the use of Portland cement in structural concrete mixtures. However, traditional formulations and prediction models are not applicable to low-carbon concrete. Therefore, this study aimed to evaluate low carbon concrete mortar matrices, focusing on cement replacement by supplementary cementitious materials (SCMs), such as fly ash, natural pozzolans and electric arc furnace slag, increasing the compactness of the mixtures, and limiting the water-binder ratio. Different binder powder contents were studied (350 and 400 kg/m3) in two types of concrete for prefabrication: dry consistency and plastic consistency. The results showed that dry consistency mixtures with a higher fly ash content allow higher compactness. Higher compactness promotes an overall increase in Young's modulus, up to 16%, for all eco-mixtures. The analysis enabled the estimation of the Feret coefficients for each combination of cement with SCMs and their correlation with a power function, dependent on the water-cement ratio. This allows the future estimation of the strength for binder pastes of mixtures incorporating different percentages of these additions.\u0000","PeriodicalId":14868,"journal":{"name":"Journal of Advanced Concrete Technology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Structural Performance of RC Members Affected by Alkali–silica Reaction According to Crack Patterns 根据裂缝形态确定受碱-二氧化硅反应影响的 RC 构件的结构性能

IF 2 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-08-22 DOI: 10.3151/jact.22.455

Hyo Eun Joo, Yuya Takahashi

{"title":"Structural Performance of RC Members Affected by Alkali–silica Reaction According to Crack Patterns","authors":"Hyo Eun Joo, Yuya Takahashi","doi":"10.3151/jact.22.455","DOIUrl":"https://doi.org/10.3151/jact.22.455","url":null,"abstract":"The structural performance of reinforced concrete (RC) members affected by alkali–silica reaction (ASR) is difficult to predict because of the multi-scale phenomena. Recent structural tests reveal that the performance of RC members also depends on ASR-induced crack patterns, including localized cracks and dispersed microcracks. Additionally, microscopic factors, such as crack-filling by gel and presence of microcracks, are relevant. To explore this in detail, a computational system for finite element analysis of ASR-damaged RC members was developed. This study numerically investigated the structural behavior of ASR-affected RC members based on localized/dispersed crack patterns and microscopic factors. The applicability of the developed computational system was verified by comparing the analysis results with experimental data. The analysis results showed that ASR-damaged RC members with dispersed microcracks exhibited highly ductile behavior, while those with localized cracks failed in shear. This is because the dispersed crack pattern prevents the shear crack propagation and enhances the mechanical contribution of gel filling cracks, while the localized ASR cracks facilitate critical crack propagation, leading to failure, and minimize the gel-filling effect. Through the analytical investigations, it was found that the localized ASR cracks can result in significant loss of structural performance; thus, this study recommends the assessment of structural capacity of RC members in the case where the localized cracks were observed.\u0000","PeriodicalId":14868,"journal":{"name":"Journal of Advanced Concrete Technology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142203727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Calcium-Magnesia Compound Expansive Agent on the Macroscopic Performance and Microstructure of Concrete 钙镁复合膨胀剂对混凝土宏观性能和微观结构的影响

IF 2 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-08-20 DOI: 10.3151/jact.22.445

Ji Xiao, Lang Jin, Feixiang Chen, Yong Leng, Guozhi Zhang, Kexin Liu

{"title":"Effect of Calcium-Magnesia Compound Expansive Agent on the Macroscopic Performance and Microstructure of Concrete","authors":"Ji Xiao, Lang Jin, Feixiang Chen, Yong Leng, Guozhi Zhang, Kexin Liu","doi":"10.3151/jact.22.445","DOIUrl":"https://doi.org/10.3151/jact.22.445","url":null,"abstract":"This study aims to discuss the effects of calcium-magnesia compound expansive agent on the mechanical strength, shrinkage, and creep of concrete. On this basis, the expansive mechanism is investigated by using XRD, TG measurement, and MIP with percolation and backbone fractal dimension analysis. It is shown that replacing fly ash with calcium-magnesia compound expansive agent has little effect on the axial compression strength, but significantly reduces the elastic modulus. Moreover, increasing the amount of expansive agent from 0% to 12% leads to a reduction in autogenous shrinkage values by 9.1% to 14.8% at 180 days while causing an increase in creep by 24.5% to 37.8%. Concurrently, the porosity of the concrete increases with the addition of the calcium-magnesia compound expansive agent, and the proportion of gel and medium capillary pores in the total porosity also increases. However, fractal dimension analysis shows that it also decreases the complexity of overall connectivity of interconnected pores. Furthermore, the results obtained from TG also indicate that the calcium-magnesia compound expansive agent is beneficial for the formation of gel hydration products.\u0000","PeriodicalId":14868,"journal":{"name":"Journal of Advanced Concrete Technology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of the Unit Content and Grading Distribution of Fine Aggregates on the Long-term Skid Resistance of Concrete Pavement 细集料的单位含量和级配分布对混凝土路面长期抗滑性的影响

IF 1.6 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-08-10 DOI: 10.3151/jact.22.431

Jaganmuthu Senthilvelan, Hidefumi Izuo, Taiju Endo, Atsushi Ueno

引用次数: 0

Cold-sintered Carbonated Concrete Waste Fines: A Calcium Carbonate Concrete Block 冷烧结碳酸混凝土废粉：碳酸钙混凝土砌块

IF 2 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-07-24 DOI: 10.3151/jact.22.406

Ippei Maruyama, Ngoc Kien Bui, Amr Meawad, Ryo Kurihara, Yuji Mitani, Hikotsugu Hyodo, Manabu Kanematsu, Takafumi Noguchi

{"title":"Cold-sintered Carbonated Concrete Waste Fines: A Calcium Carbonate Concrete Block","authors":"Ippei Maruyama, Ngoc Kien Bui, Amr Meawad, Ryo Kurihara, Yuji Mitani, Hikotsugu Hyodo, Manabu Kanematsu, Takafumi Noguchi","doi":"10.3151/jact.22.406","DOIUrl":"https://doi.org/10.3151/jact.22.406","url":null,"abstract":"Cementitious materials generally have large carbon footprints because of the high CO2 emitted during Portland cement production. This is because limestone is used as an essential CaO resource, and its decomposition by calcination emits CO2. From this perspective, the concrete in urban buildings can be considered an urban mine of CaO resources. In this study, we propose obtaining a solidified product by crushing all the waste concrete, carbonating it, pressurizing it with a calcium bicarbonate solution, and drying it. The experimental results show that the bicarbonate solution, high-temperature conditions, and extended loading period produce a higher strength. In addition, neck growth at the contact surfaces of the carbonated concrete fines was confirmed using scanning electron microscopy. Consequently, the proposed method indicates that the hardening mechanism is the cold sintering of calcium carbonate on the surface of fine-carbonated concrete particles. This method allows the developed blocks to be used semi-permanently with relatively low energy consumption through repeated crushing and re-pressurization.\u0000","PeriodicalId":14868,"journal":{"name":"Journal of Advanced Concrete Technology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of Rebar Strength, Pre-treatment, and Measurement Method on Residual Stress Measurement using Portable X-ray Diffractometer 钢筋强度、预处理和测量方法对使用便携式 X 射线衍射仪测量残余应力的影响

IF 2 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-07-24 DOI: 10.3151/jact.22.391

Ryohei Yanagida, Saiji Fukada, Toshihiko Sasaki

{"title":"Influence of Rebar Strength, Pre-treatment, and Measurement Method on Residual Stress Measurement using Portable X-ray Diffractometer","authors":"Ryohei Yanagida, Saiji Fukada, Toshihiko Sasaki","doi":"10.3151/jact.22.391","DOIUrl":"https://doi.org/10.3151/jact.22.391","url":null,"abstract":"It is effective for the maintenance of existing structures to understand the current status, such as the residual stress of the materials used, and a portable X-ray diffractometer is used as a technique for measuring steel stress. Although measurement methods and pre-treatment for steel bars with low strength have been revealed, the influence of the strength on the X-ray stress measurement and the appropriate measurement method has not been clarified. In this study, residual stress measurements using the X-ray diffraction are performed on steel bars, the differences in the results for various steels with different strengths are discussed, and measurement conditions for accurate measurement are reported. In addition, the cause of the tendency of the X-ray stress measurement to be smaller than the actual increment value under high stress is investigated. The experimental results show that the appropriate measurement conditions vary depending on the rebar strength, and that the X-ray stress measurement under high stress also varies. The metallurgical structure of the steel was shown to be related to the cause of this phenomenon through microstructural observation and analysis of the deformation behavior.\u0000","PeriodicalId":14868,"journal":{"name":"Journal of Advanced Concrete Technology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of a Large-scale Thermogravimetry and Gas Analyzer for Determining Carbon in Concrete 开发用于测定混凝土中碳含量的大型热重仪和气体分析仪

IF 2 4区工程技术

Journal of Advanced Concrete Technology Pub Date : 2024-06-24 DOI: 10.3151/jact.22.383

Ippei Maruyama, Koichiro Noritake, Yoshinobu Hosoi, Haruka Takahashi

{"title":"Development of a Large-scale Thermogravimetry and Gas Analyzer for Determining Carbon in Concrete","authors":"Ippei Maruyama, Koichiro Noritake, Yoshinobu Hosoi, Haruka Takahashi","doi":"10.3151/jact.22.383","DOIUrl":"https://doi.org/10.3151/jact.22.383","url":null,"abstract":"One carbon neutralization measure applied in the concrete sector is the use of artificial carbonate in concrete for immobilization. This CO2 reduction technology corresponds to the CO2 emitted during concrete production. When considering the marketability of these technologies, especially for newly developed products in the carbon market, it is essential to quantify the amount of CO2 fixed as inorganic carbonate. Additionally, as a representative test specimen for concrete containing aggregate, a φ100 × 200 mm cylinder specimen is conventionally used for physical property evaluation. To evaluate the amount of CO2 fixed in one batch of concrete, a mass far from that of the conventional chemical analysis sample may need to be analyzed. Therefore, in this study, we investigated a pulverization process for concrete analytical materials. We also propose a new analytical apparatus that can be used to measure large cylinder specimens. Experimental results showed that the newly developed analyzer, equipped with a mass balance and CO2 and H2O gas analyzer for large cylinders, exhibited excellent analytical variability and measurement speed performance. It was also inferred that the homogenization process is necessary to grind the entire cylindrical concrete specimen into a fine powder and homogenize it to improve the representativeness of the concrete.\u0000","PeriodicalId":14868,"journal":{"name":"Journal of Advanced Concrete Technology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141511573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0