bluuebunny/crossref_metadata_2025 huggingface dataset:
Higher education reputation management through increasing the role of public relations
Authors: Anggarina Paula Tjatoerwidya , Irawan Agustinus Purna , Dewi Fransisca Iriani Roesmala
Published: August 2024

A university's reputation is an important factor in winning the competition and ensuring sustainability. The reputation built by a university must be about its vision and mission. Reputation needs to be managed professionally by an organization namely quality public relations as the spearhead in delivering and communicating information to all university stakeholders. This research aims to formulate how to manage the   reputation of higher education by increasing the role of public relations. The research method used is a descriptive analysis method that combines surveys through questionnaires and in-depth interviews with stakeholders as the main informants. It can be concluded that public relations play an important role in managing higher education reputation based on the results of the research. The built reputation must be based on the values adopted because they become the guideline and direction of the college's development goals. A university's reputation is influenced by accreditation, quality of graduates, human resources, leadership, college rankings, facilities, curriculum, services, community service and innovation, publications and collaborations. Negative factors such as violence, bullying, plagiarism and diploma forgery have the potential to reduce reputation. In reputation management, public relation has a role as a liaison to stakeholders in conveying information about the reputation of higher education. Public relations must manage negative factors that can reduce reputation. The results of this study will be a reference for further research.
Detection and localization of wrist fractures in x-ray imagery using deep learning teaching
Authors: Mohammed Haider Abdulbaqi Abbas , Ahmed Shaymaa Taha , Zaki Rana Mohammed Hassan , Kadhim Qusay Kanaan
Published: August 2024

Hospitals often refer patients with wrist fractures, particularly to their emergency rooms. To accurately diagnose these illnesses and choose the appropriate course of therapy, doctors must evaluate images from various medical equipment, medical data, and a physical assessment of the patient. This project attempts to use deep learning on these images to identify wrist X-ray fractures and help physicians diagnose them, particularly in emergency departments. This study employs a dataset comprising both fractured and regular wrists to assess the extent to which the Recurrent Neural Network with 22 Convolutional Neural Network layers (RN22-CNNs) transfers knowledge for fracture identification and classification. We evaluate the diagnostic accuracy of the RN-21CNN model against four popular transfer learning models, namely Visual Geometry Group (Vgg16), ResNet-50, Inception V3, and Vgg19. We used the model on a dataset of 1644 X-rays collected from the Kaggle repository. Next, we trained, verified, and tested the adapted (RN22-CNNs) model. The proposed model had an accuracy of 96.61%. The proposed Computer-Aided Diagnosis System (CADS) will save medical practitioners' burden by accurately identifying fractures.
Antioxidant properties, antidiabetic activity, and GC-MS phytochemical analysis of wheat-based bread fortified with celosia argentea seed flour
Authors: Azeez Lukuman Akande , Babalola Kafayat Adebukola , Osunrinade Oludolapo Akinyemi
Published: August 2024

Pseudocereals like Celosia argentea seed have been indicated to have numerous therapeutic and prophylactic potentials that are yet to be incorporated into food materials. This study evaluated the antioxidant properties, antidiabetic potential, and phytochemicals of wheat-based bread fortified with Celosia argentea seed flour. Bread samples were produced using standard methods, fortifying refined and whole wheat with 5 and 10% Celosia argentea seed flour. The antioxidant properties and α-amylase inhibition of bread samples were determined using standard methods. The phytochemicals present in the methanolic extracts of bread samples were identified with Gas Chromatography-Mass Spectrometry (GCMS). Statistical significance was tested at α0.05. The result of the antioxidant properties for bread samples were Total flavonoid content (0.61-0.85 mg/g), Total Phenolic Content (1.1-1.31 mgGAE/g), total antioxidant capacity (1.19-3.34 mgGAE/g), Ferric reducing antioxidant power (0.13-0.54 mg/g) and DPPH (42.58-49.75%). The IC50 values obtained for Celosia argentea seed substituted wheat bread ranged between 58.20 and 171.05 μg/mL. The antioxidant properties and α-amylase inhibition showed a significant (p<0.05) increase as the percentage of inclusion of Celosiae argentea seed increased. Bioactive compounds detected in bread samples produced by the fortification of wheat flour (whole and refined) with Celosia argentea seed flour include 9,12-Octadecadienoic acid methyl ester; Docosanoic acid, methyl ester; E,E,Z-1,3,12-Nonadecatriene-5,14-diol; Linoleic acid ethyl ester; and Squalene. The predominant health benefits of phytochemicals detected in bread samples fortified with C. argentea seed were anti-inflammatory potentials, antioxidant protection, and reduction of lipid peroxidation. Including Celosia argentea seed impacted the antioxidant and antidiabetic potential of bread samples.
Resistance of four mutant rice (Oryza sativa L.) Varieties to iron toxicity at Njala inland valley swamp ecology in southern Sierra Leone
Authors: Yankson Dennis Philip Yaw , Kanu Sheku Afred , Mansaray Ibrahim , Bah Alieu Mohamed
Published: August 2024

Four lowland rice varieties were examined for tolerance to Fe toxicity using morphological traits. In 2021, at the Njala Agricultural Research Centre (NARC), we conducted a field trial at the Inland Valley Swamp (IVS) in Sierra Leone. The four rice varieties, Bina 8, 10, 17, and Early Mutant, were planted in a randomized complete block design with three replications. The variance analysis revealed significant differences in all four rice varieties' traits. Elemental analysis of plant stalk revealed that Early Mutants and Bina 17 had the lowest Fe2+ concentrations (0.4 mg/kg soil and 0.8 mg/kg soil, respectively). On the other hand, Bina 10 and Bina 8 had higher Fe2+ concentrations (3.5 mg/kg soil and 1.5 mg/kg soil, respectively). In contrast, Bina 8 and Bina 10 had higher Fe2+ concentration values in their roots and stalks, indicating a higher accumulation of Fe2+. Thus, these two varieties also had the highest yield, indicating they tolerate Fe toxicity. This finding implies that rice varieties' capacity to withstand Fe toxicity plays a crucial role in sustaining growth and yield in Fe-toxic environments. The study concludes that screening rice varieties for Fe toxicity tolerance is important, but further research is needed to understand the mechanisms underlying Fe toxicity tolerance in rice.
Utilization of Indian gooseberry (Phyllanthus emblica L.) as foods
Authors: Cheekham Phuriwat , Kaewsritong Jiraphat , Srikaeo Khongsak
Published: August 2024

This study aimed to investigate the consumption of amla as a food by conducting a thorough literature analysis and a field survey with unstructured, in-depth interviews. Amla or Indian gooseberry (Phyllanthus emblica L.) is rich in phytochemicals, and their pharmaceutical potentials have been extensively reported. However, their utilization as foods is not well documented. Thai recipes use whole or minced fresh amla fruits as an ingredient in some spicy dishes, such as chili pastes, soups, and salads. Like other Asian countries, amla could be processed into products such as juice, preserves, pickles, and dried amla. Ten amla dishes and products were selected for evaluation of their ascorbic acid contents and antioxidant properties (total phenolic compounds, total flavonoids, DPPH, and FRAP assays). High-heat processing resulted in a marginal reduction of ascorbic acid in amla dishes and products. Processing methods also affected antioxidant activities, and they varied depending on processing conditions and product types. The processing of amla into juice slightly decreased antioxidant activities. Thai foods that used amla as an ingredient exhibited less antioxidant activity than those made of fresh amla. The antioxidant activities of pickled and preserved amlas were substantially diminished due to their high salt and sugar content. On the contrary, dried amla demonstrated enhanced antioxidant activities as a result of its reduced moisture content and the presence of concentrated phytochemicals. Given its substantial phytonutrient content and lack of utilization, the results obtained from this research contribute to the promotion of amla as a valuable food ingredient.
Assessing knowledge and awareness levels regarding cervical cancer and HPV vaccination in the Jammu regions
Authors: Jasrotia Ridhima , Kashyap Isha , Suri Jyotsna , Chopra Chirag , Wani Atif Khurshid , Tizro Nazli , Goyal Abhineet , Singh Reena
Published: August 2024

Background and Objectives: Cervical cancer global burden is highly skewed towards poor countries primarily due to lack of awareness, poor screening, and low uptake of prophylactic vaccines. The purpose of our study is to educate and raise awareness among young girls and women about the importance of cervical screening and HPV vaccination.
Materials and Methods: The present study, conducted from January 2023 to December 2023, focused on students, teachers, housewives, and healthcare professionals in the Jammu region to assess their awareness of cervical cancer and the HPV vac- cine. HPV DNA testing was carried out using the Truenat Real-Time PCR method at Swastik Diagnostic Laboratory, Jammu.
Results: Knowledge of cervical cancer, awareness of the HPV virus, and the vaccination status of women were assessed in survey. In the HPV screening test, out of 2,400 women, 106 tested positive for HPV. Among these 106 women, 19% had a high viral load (Ct < 20), 11% had a low viral load (25 ≤ Ct < 30), indicating a low relative concentration of HPV viruses, 40% had a medium viral load (20 ≤ Ct < 25), and 30% had very low viral loads (Ct ≥ 30).
Conclusion: These findings highlight the importance of routine cervical screenings, such as Pap smears and HPV tests, for the early detection of cervical cancer. There is an urgent need to implement cervical cancer screening and vaccination pro- grams in the Jammu region.
Inhibitory effect of Nigella sativa oil loaded to liposomal nanocarriers on Candida parapsilosis isolates
Authors: Shamloo Ardalan Ghiaee , Zarrinfar Hossein , Jaafari Mahmoud Reza , Yadegari Mohammad Hossein
Published: August 2024

Background and Objectives: Candida parapsilosis is the second most common species causing infectious diseases and can lead to biofilm resistance. This study aims to adjust and synthesize a liposomal compound of Nigella sativa and evaluate its antifungal properties against C. parapsilosis isolates.
Materials and Methods: The liposomal formulation of N. sativa was optimized through the utilization of transmission elec- tron microscopy (TEM), particle size analysis, zeta potential measurement, and UV-visible spectrophotometry. Furthermore, an MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay was conducted on peripheral blood mononu- clear cells (PBMCs). The antifungal efficacy was evaluated in accordance with the M27-A3 guideline.
Results: The minimum inhibitory concentrations (MICs) of N. sativa oil and the liposomal formulation on C. parapsilosis isolates ranged from 128 to 8 µg/mL and from 250 to 31.25 µg/mL, respectively. The MIC and MIC values of N. sativa oil and the liposomal formulation were 125, 187, and 32, 96 µg/mL, respectively. The viability percentage of cells treated with the liposomal formulation and free N. sativa oil was 91% and 85%, respectively.
Conclusion: The cytotoxicity of free N. sativa was significantly reduced when using nanoliposomes. The liposomal form of N.sativa showed greater antifungal properties compared to the free N. sativa extract against C. parapsilosis isolates.
Antibacterial Activity of Some Iranian Herbal Essential Oils as Disinfectant Agents on Surfaces Contaminated with Methicillin -resistant -Staphylococcus Aureus and Carbapenem - resistant -Pseudomonas Aeruginosa
Authors: Bastani Nejad Zahra , Nikrouz Laila , Abdollahi Abbas
Published: August 2024

Background & Objectives: Different essential oils (EOs) with antibacterial activities are promising natural sources for providing novel disinfectant agents for hospital surfaces
Materials & Methods: The component and antibacterial effects of six EOs, including Cuminum cyminum (CCEO), Artemisia sieberi (ASEO), Laurus nobilis (LNEO), Ferula gummosa (FGEO), Lippia citriodora (LCEO), and Cymbopogon citratus (CIEO) were assessed by GC -MS and 96 -well micro -plates (IC50), against Staphylococcus aureus (S. aureus) ATCC 25923, Pseudomonas aeruginosa (P. aeruginosa) ATCC 27853 and clinical isolates of methicillin -resistant S. aureus (MRSA) and metallo -beta -lactamase (MBL) -producing P. aeruginosa. Then, the antibacterial effects of FGEO, the most effective EO, were evaluated on the trolley surface in a hospital for 1, 3, 5 and 10 min intervals.
Results: CCEO, ASEO, and FGEO exerted the highest antibacterial activity against S. aureus, while CIEO and LNEO inferred the highest activity against P. aeruginosa. In addition, FGEO mitigated the growth of S. aureus and P. aeruginosa on the trolley surface (P<0.05).
Conclusion : The studied EOs could be novel encouraging agents to develop further green antimicrobial agents against different infections. In addition, FGEO exhibited considerable antibacterial effects on the surface of the trolley.
Protective Effect of Oleuropein on Memory Impairment and Oxidative Stress in Streptozotocin -Induced Diabetes Rats via Modulation of NF -kB and Nrf-2 Pathways
Authors: Shaibani Zahra , Rafieirad Maryam
Published: August 2024

Background & Objectives: Diabetes is the most common metabolic disease which is associated with hyperglycemia and long -term complications. This study aimed to elucidate the anti -diabetic role of oleuropein (OLE) in a streptozotocin (STZ) -induced diabetic animal model.
Materials & Methods: Adult male Wistar rats (200 –250 g) were randomly divided into four groups: 1) Control group, 2) STZ group: diabetic rats that received STZ (60 mg/kg), 3) OLE 50 group: diabetic rats treated with oral OLE at 50 mg/kg of body weight daily for 28 days, and 4) OLE 100 group: diabetic rats treated with oral OLE at 100 mg/kg of body weight daily for 28 days. Memory function and biochemical factors such as malondialdehyde (MDA) levels, glutathione peroxidase (GPx), and total thiol activity were evaluated in the rats' cerebral cortex and striatum tissues. Moreover, nuclear transcription factor -kappa B (NF - κB) and nuclear factor E2 -related factor 2 (Nrf2) pathway s activation were determined in cerebral cortex and striatum tissues by real -time polymerase chain reaction (RT -PCR).
Results: Chronic administration of OLE ameliorated cognitive deficits and attenuated oxidative stress induced by diabetes. Additionally, OLE significantly prohibited the activation of the pro -inflammatory marker NF - κB and downregulated Nrf2 expression in STZ -induced diabetic rats.
Conclusion : Our results confirm the significant protective role of OLE against STZ -induced diabetes in rats by up -regulating Nrf2 signaling and enhancing antioxidant activity.
Enhancing Digital Payment Security with Biometric Authentication and AI: A Big Data Approach
Authors: Komarraju Anil Kumar , Ramprasad Mondeti , Rao Malleneni Bhasker
Published: August 2024

The arrival of digital payment technologies has brought unprecedented convenience to businesses and consumers. However, the rapid adoption of digital payments relies on both parties trusting the technology to handle their transactions securely and accurately. Conventional approaches to security issues rely on complex and frequent updates to the software that underpins digital payment systems, as well as cryptographic solutions that are challenging to implement and may, from time to time, require replacement as older systems are hacked. The introduction of biometric data-driven payment security enhances the current security systems, reducing system overheads, and increasing customer confidence in the technology. Our approach is to leverage advances in Artificial Intelligence (AI) systems, driven by the latest developments in big data technology. This novel combination is capable of improving the dynamic three-tier digital payment security model, ultimately reducing both fraud and overheads and increasing trust from both businesses and consumers.
Outside Broadcasting Introduction and Basics
Authors: Almane Saad
Published: August 2024

This book was made for any individual who needs to make quality video creations. it's for starting experts the same. We don't expect that you just have past creation experience, yet the substance is profound enough that starting experts can exploit it. more than once, we've utilized photos and representations from the absolute best degrees of creation. The objective is to offer you models that you essentially can adjust to any level at which you're working
MECHANICAL IMPACTS OF COMPLETE AGGREGATE SUBSTITUTION IN ALKALI ACTIVATED CONCRETE PAVEMENT
Authors:   University of Tehran, Iran, Amani Ali , Ramezanianpour Amir Mohammad ,   University of Tehran, Iran, Sabokpa Saeed ,   University of Tehran, Iran
Published: August 2024

There are environmental impacts associated with the construction of necessary infrastructures. Concrete is the most used construction material. To reduce the environmental impact of construction, we can use alternatives to Portland cement and recycled aggregates in concrete production. This study used non-reactive electric arc furnace slag (EAFS) and alkali-activated concrete (AASC). The goal was to reduce CO2 emissions while maintaining desired mechanical and durability properties. Tests showed that the mix designs had excellent properties. Full substitution of aggregates resulted in compressive strength of 47 MPa at 28 days, but a 6% reduction compared to AASC with natural aggregates. This pattern is repeated for other mechanical properties. Substituting all aggregates led to a 30% reduction in water absorption performance compared to AASC with natural aggregates. Choosing sustainable and eco-friendly concrete types can reduce a structure's environmental impact and carbon footprint. This is crucial for a more sustainable future.
DEVELOPMENT OF ECO-FRIENDLY ALKALI-ACTIVATED CONCRETE FOR 3D PRINTING
Authors:   Ghent University, Belgium, Luyten Kito , Mohan Manu K. ,   Ghent University, Belgium, Sun Yubo ,   Ghent University, Belgium, Ghorbani Saeid ,   Ghent University, Belgium, Matthys Stijn ,   Ghent University, Belgium, Van Tittelboom Kim ,   Ghent University, Belgium
Published: August 2024

Extrusion-based concrete 3D printing has huge potential to become a sustainable solution to the construction sector due to its advantages over the traditional mould based construction method. However, current 3D printable mixtures are not eco-friendly as they have significantly higher binder content compared to mould cast concrete. One of the solutions to this problem is the use of alkali-activated materials (AAMs). AAMs are made from industrial by-products being considered as alternatives for Portland cement. Though there is increasing attention towards AAM based concrete materials, their application in printed concrete is still limited due to the lack of a proper understanding of mixture design strategies. In this paper, pure and blended AAM based 3D printable mixtures were developed by using ground granulated blast-furnace slag (GGBS), stainless-steel slag (SSS) and copper slag (CS) as precursors. The GGBS based mixtures showed a good balance between flowability, open time and strength gain. The executed prints demonstrated a strength comparable with cast samples, highlighting an excellent interlayer bond strength.
VERSATILITY AND DECARBONIZING EFFECT OF CONCRETE MIXED WITH BIOCHAR
Authors:   Institute of Technology, Shimizu Corporation, Japan, Yamamoto Shinya , Yukita Keiji ,   Civil Engineering Technology Division, Shimizu Corporation, Japan, Tanaka Hirokazu ,   Institute of Technology, Shimizu Corporation, Japan, Kubo Masafumi ,   Civil Engineering Technology Division, Shimizu Corporation, Japan, Shimizu Kazuaki ,   Institute of Technology, Shimizu Corporation, Japan
Published: August 2024

The authors are investigating concrete mixed with biochar made from sawdust with the aim of developing a concrete that is both versatile and carbon neutral. Since biochar fixes organic carbon, it has the effect of fixing CO2, and therefore, when stored in a long-term stable object such as concrete, it has a carbon sequestration effect. By offsetting the CO2 equivalent to the stored carbon from the CO2 emissions derived from the concrete material, carbon neutral concrete with total CO2 emissions of zero or less can be realized. The effect of CO2 fixation by carbon sequestration was estimated when biochar was mixed with concrete based on IPCC guidelines. The fresh properties and compressive strength of biochar concrete were experimentally confirmed using biochar particle size and admixture volume (up to 60 kg/m3) as experimental factors. The fresh properties were found to be adjustable, although the amount of chemical admixture needed to be increased. The compressive strength was found to be comparable at maximum to that without biochar. Biochar concrete was applied to temporary pavement concrete at a construction site, and it was confirmed that there were no problems with workability and compressive strength.
CHLORIDE-INDUCED CORROSION OF STEEL REBARS IN CONCRETE WITH LOW BINDER CONTENT
Authors:   Federal University of Paraiba, João Pessoa, Brazil, Cândido Taíssa , Meira Gibson ,   Federal University of Paraiba, João Pessoa, Brazil,   Federal Institute of Education, Science and Technology of Paraiba - IFPB, Brazil
Published: August 2024

To enhance sustainability in the construction sector and reduce CO2 emissions, low-binder concretes arise as an alternative. In this scenario, the use of limestone filler as cement replacement, which is available in a large scale, becomes a suitable alternative. This study evaluates the impact of replacing 30% and 60% of Portland cement by limestone filler on compressive strength, chlorides transport and corrosion propagation in concrete mixtures. The findings reveal that the concretes with low binder contents meet the minimum compressive strength for concrete structures recommended by Brazilian standard. Nevertheless, the reduction in Portland cement content promoted a lower concrete pH and decreased C3A content. This led to higher diffusion coefficients but did not mean a higher content of chlorides accumulated into concrete for C250, which means that, chloride diffusion coefficient needs to be analysed together with other variables and that the performance of low-binder content concretes can be equivalent or even superior in some properties.
RHEOLOGICAL PROPERTIES OF EXTRUDED STABILIZED EARTH
Authors:   Institut de Recherche Dupuy de Lôme (IRDL), France, Bouzinac Solène ,   Centre Technique de Matériaux Naturels de Construction (CTMNC), France,   Laboratoire des Matériaux Durables de Construction (LMDC), Université de Toulouse, France, Guihéneuf Simon ,   Institut de Recherche Dupuy de Lôme (IRDL), France, Perrot Arnaud ,   Institut de Recherche Dupuy de Lôme (IRDL), France, Maillard Pascal ,   Centre Technique de Matériaux Naturels de Construction (CTMNC), France, Aubert Jean-Emmanuel ,   Laboratoire des Matériaux Durables de Construction (LMDC), Université de Toulouse, France
Published: August 2024

Fired clay bricks are efficiently shaped by extrusion and such process can be advantageously adapted to earthen materials. In the context of laboratory-scale research simple, accurate and reproducible tests are needed to qualify the extrudability of an earthen material. In this study, the adaptation of the fall cone is studied to meet these requirements. Using the geometrical dimensions of the cone, it is possible to determine the shear stress of the studied material according to the penetration depth. Thus, a rheological approach can stem from these geotechnical tests for different soils. The first objective is to determine an extrudability criterion for different earthen materials. Additionally, mineral stabilization using cement or lime modifies the initial consistency of soils and may induce a rapid loss of plasticity with time. It is expected to pave the way toward the control of the extrusion of stabilized earth at the laboratory scale.
CARBONATION TREATMENT OF RECYCLED COMPACTED CEMENT PASTE: EFFECT OF TEMPERATURE AND PRESSURE ON PHYSICAL PROPERTIES
Authors:   Mitsubishi UBE Cement Corporation, Japan, Kobayashi Mari , Takahashi Keisuke ,   Mitsubishi UBE Cement Corporation, Japan
Published: August 2024

The amount of construction and demolition waste, large amount of which is concrete, continues to increase. Development of effective utilization technique for recycled concrete fines (RCF) generated in the process of producing recycled aggregates is required. This study proposes a method to obtain hardened specimen by powdering RCF to less than 300 μm, compacting it at a pressure of 0.6 MPa and carbonating the specimen by using pressure chamber at a temperature less than 60 °C and pressure less than 3 MPa. The carbonation hardened specimen showed a maximum compressive strength of 43.6 N/mm2. It is believed that calcium from cement paste was dissolved and re-precipitated as calcium carbonate during the carbonation process, filling the small pores and thus hardening the specimen. In addition, particle size distribution of powdered RCF could relate to the compressive strength. This RCF recycling technology can be used for building material products such as tiles.
DEVELOPMENT OF 3D PRINTED CEMENTITIOUS MATERIALS: MIX AND MACHINERY DESIGN
Authors:   University of Washington, USA, Lehman Dawn , Ganter Mark ,   University of Washington, USA, Kuder Katherine ,   Seattle University, USA, Roth Jacob ,   University of Washington, USA, Stenslie Hailey ,   University of Washington, USA
Published: August 2024

Three-dimensional (3D) printing of cementitious materials is an attractive technology for structural applications due to decreased construction time, design versatility, and possible superior mechanical performance and durability. However, challenges exist in processing because components rely on green strength and stiffness to resist instability during construction. This research investigates cementitious mix design and extrusion techniques to advance engineering of 3D printed composites. In the first phase, extrudable mix designs were developed. In the second phase, the mechanical engineering design of the extruder (pump pressure, motor properties, rotating versus sliding piston, bearing design, and gantry stiffness) was investigated. The study found: (1) methylcellulose can provide shape stability, (2) sand is challenging due to phase migration under high pressures, and (3) a piston-driven extruder capable of providing pressures exceeding 345 kPa (50 psi) is needed to print these mix designs.
LINKING MICROSTRUCTURE ASPECTS AND MECHANICAL BEHAVIOUR OF WOOL REINFORCED COMPOSITES
Authors:   DISEG, Politecnico di Torino, Italy, Fantilli Alessandro , Jóźwiak-Niedźwiedzka Daria ,   Polish Academy of Sciences, Poland, Antolik Aneta ,   Polish Academy of Sciences, Poland, Denis Piotr ,   Polish Academy of Sciences, Poland
Published: August 2024

The necessity of tailoring more environmentally friendly materials has prompted researchers and practitioners to explore new and more sustainable components for cement-based mixtures. Some of these materials are in their natural state and they can also be used to improve the mechanical performances of cementitious composites. Sheep wool, which is nowadays considered a special waste, can substitute some polymeric fibres to increase the fracture toughness. However, in alkaline environment, wool fibres tend to degrade within a few days after casting, so fibres can lose the reinforcement function of concrete and mortars due to long term durability issues. A series of tests have been performed with the aim of examining the microstructure and measuring the mechanical properties of wool-reinforced pastes made with various types of cement. By linking the results of microstructural analyses with those of the mechanical tests, it is possible to argue that the lower the pH of the paste the larger the efficiency of wool fibres.
EFFECT OF CEMENT ADDITION ON SHRINKAGE PROPERTIES OF FLY ASH-BASED GEOPOLYMER
Authors:   Tokyo Institute of Technology, Japan, Lim Horhok , Iwanami Mitsuyasu ,   Tokyo Institute of Technology, Japan, Chijiwa Nobuhiro ,   Tokyo Institute of Technology, Japan, Nakayama Kazuhide ,   Tokyo Institute of Technology, Japan
Published: August 2024

While being known as an environmentally friendly construction material, geopolymer exhibits large drying shrinkage due to its unique hardening process, and adding cement is thought to mitigate the shrinkage. This paper presents the results of the experimental investigation on the changes in shrinkage properties of fly ash-based geopolymer, and their mechanisms. Results of the shrinkage measurement showed both increase and decrease in shrinkage of cement incorporated geopolymer governed by curing conditions. Specimens shortly cured at low temperature had lower compressive strength, causing shrinkage to largely be influenced by evaporation level. Specimens with high curing temperature and long curing period, on the other hand, have strong skeleton, making them highly resistance to drying shrinkage. MIP results confirmed that adding cement flattens pore size distribution curve and shifts its peak to smaller pore size which increases the magnitude of shrinkage.
STUDY ON 3D MESOSCALE STRUCTURAL ANALYSIS OF CRACKING BEHAVIOUR BY SCDA TOWARDS THE BETTER DEMOLITION
Authors:   Tokyo University of Science, Japan, Takahashi Hayato , Joshi Suhas ,   The University of Tokyo, Japan, Nagai Kohei ,   Hokkaido University, Japan, Kato Yoshitaka ,   Tokyo University of Science, Japan
Published: August 2024

This research is a fundamental study to develop the analytical technique for cracking behaviour of RC structures by use of Soundless Chemical Demolition Agent (SCDA). The reproducibility of primary crack propagation direction was verified between elemental test experiment using small plain concrete specimen and 3D-RBSM analysis. Then, the analysis targeting the small RC specimen’s model was carried out as the parameters of the SCDAs’ arrangement and stirrups. Fundamentally, stirrups in the specimens prohibit propagation of primary cracks but injection of SCDAs into adjacent stirrups’ span enforces the connection of cracks between SCDAs. From the viewpoint of the crack width distribution, fine cracks in the width of less than 0.3mm increases due to the stirrups.
INFLUENCE OF WATER COMPENSATION ON MECHANICAL PERFORMANCE AND DURABILITY OF MIXED RECYCLED AGGREGATE CONCRETE
Authors:   KU Leuven Brugge Campus, Department of Civil Engineering, Belgium, Hao Haoyu , Vandewalle Lucie ,   KU Leuven (Arenberg), Department of Civil Engineering, Belgium, Gruyaert Elke ,   KU Leuven Ghent Campus, Department of Civil Engineering, Belgium, Li Jiabin ,   KU Leuven Brugge Campus, Department of Civil Engineering, Belgium
Published: August 2024

Extra water in addition to effective water is commonly added to compensate for water absorbed by the recycled aggregates in concrete. This study aims at investigating the effect of the water compensation method (WCM) on physical and mechanical properties, and the freeze-thaw performance of concrete with mixed recycled aggregate (MRA). The research varies MRA replacement percentage (25% and 50%) and the WCM (additional free water and pre-wetting). Results show that the WCM has a significant impact on concrete performance. The 100% additional free water compensation results in the highest initial slump, lowest strength, and worst freeze-thaw resistance. The pre-wetting method can lead to better mechanical performance and frost resistance than the additional free water method. Electrical resistivity decreases with the presence of MRA in concrete but was not significantly influenced by the WCM. To conclude, selecting an appropriate WCM can give MRA concrete comparable or superior performance to limestone concrete.
IMPROVING THE PROP ERTIES OF RECYCLED CONCRETE BY USING SURFACE TREATED FINE MIXED RECYCLED AGGREGATES
Authors:   Polytechnic University of Catalonia, Spain, Corominas A. , Etxeberria M. ,   Polytechnic University of Catalonia, Spain
Published: August 2024

Mixed Recycled Aggregates (MRA) are the most common Construction and Demolition Waste (C&DW) recycling products in southern European countries. However, their lower properties compared with natural aggregates, especially water absorption, prevent their reintroduction in the construction market. The quality of fine MRA was improved by applying two surface treatment methods (silane-based emulsion and waterglass). Both techniques revealed promising water-absorption reductions of MRA. The effects of surface-treated MRA on recycled aggregate concrete (RAC) properties, made using 100% fine MRA replacing natural sand, were also investigated. The RAC produced using treated with waterglass (5%) MRA achieved 20-27% higher compressive strength than that of RAC produced with untreated RAC, showing a higher increase in MRA with more ceramic-particle content. In addition, when applying surface treatments, the study proved that RAC with MRA could reach mechanical and durability properties similar to those from conventional concretes.
A Study of DEF Expansion Suppression Mechanism by Ground Granulated Blast Furnace Slag
Authors:   Shibaura Institute of Technology, Japan, Takeshi Iyoda , Seishi Goto ,   Yamaguchi University, Japan
Published: August 2024

DEF (Delated Ettringite Formation) is a major problem in concrete deterioration, and the conditions under which DEF occurs have been sorted out in previous studies. However, there are cases in which DEF does not lead to expansion. In particular, it has been reported that the expansion is suppressed when ground granulated blast furnace slag (GGBS) is added to the mixture, however the mechanism of this suppression remains unclear. In this study, it was produced using mortars with GGBS replacement rates varying from 0-70%. Measurements of the amount of expansion of DEF showed that the expansion was suppressed as the replacement ratio increased. Here, a replacement ratio of 25% could suppress the expansion after 150 days. On the other hand, the XRD results showed that DEF was generated in all samples, and we speculated that the suppression mechanism might be the formation of pore structure and C(A)SH.
SUGGESTION FOR ENVIRONMENTALLY FRIENDLY TSC WITH OPTIMIZED GROUTING MATERIALS
Authors:   Shibaura Institute of Technology, Japan, Yurika Noguchi , Takeshi Iyoda ,   Shibaura Institute of Technology, Japan
Published: August 2024

Various types of concrete have been developed to adapt to manufacturing methods, construction environments, and various performance requirements. Two Stage Concrete is one of them which is made by spreading coarse aggregate on the formwork and them fill the spaces between the coarse aggregate with grout material prepared with pre-mixed mortar and become concrete. This study first examined the preparation of grouting materials using materials which is environmentally friendly. As a result, that the compressive strength of the grout material itself had no significant effect on the compressive strength of the TSC. On the other hand, when is the fresh performance of the grout material, we confirmed that the use of the supernatant water of sludge in the mixing water ensured optimal performance of the grout material with 70% replacement of GGBS. Finally, it is considered necessary to consider further strength assurance to realize TSCs aimed at reducing environmental impact.
DEVELOPMENT OF A CURING PLANNING METHOD CONSIDERING BOTH LOW CARBONIZATION AND PRODUCTIVITY
Authors:   Technical Research Institute, HAZAMA ANDO Corporation, JAPAN, Fukudome Kazuto , Saito Atsushi ,   Technical Research Institute, HAZAMA ANDO Corporation, JAPAN
Published: August 2024

Curing of concrete is a very important work process for constructing a concrete structure with the required performance. Although the importance of curing is widely recognized, it is generally recognized that there is no curing planning method. From this background, the authors have proposed “Curing planning method based on cement hydration analysis”. In this method, the hydration of cement achieved by curing is predicted by hydration analysis, and the curing period is calculated so as to obtain the target hydration rate to ensure the required performance. While the productivity improvement of concrete work is a problem, it is not enough to just find the curing period to ensure performance. Therefore, we investigated a curing planning method that considers both productivity and performance. On the other hand, in order to achieve carbon neutrality, there is an urgent need to expand the use of low-carbon cement. Since low-carbon cement develops strength slowly, it is necessary to extend the curing period, and there is concern about a decrease in productivity. From that point of view, we examined a method of formulating a curing plan that considers both productivity and low carbonization. As a result of the study, it was found that it is possible to achieve both productivity and performance by appropriately setting the design age. Therefore, we investigated a method of calculating the design age to control the curing period and examined a method of correcting the mixture proportion based on the calculated design age. As a result, it was shown that it is possible to correct the mixture proportion to achieve both productivity and performance from the calculated design age and the formula for compressive strength and mass transfer resistance. And it was shown that even when low-carbon cement is used, it is possible to formulate a curing plan that considers both low- carbonization and productivity improvement by appropriately setting the design age. In addition, specific calculation examples under various conditions were presented, and it was shown that the proposed curing planning method can reasonably achieve both low carbonization, productivity, and performance.
RETROFITTING OF SEVERELY CORRODED CONTINUOUS RC BEAMS WITH C-FRCM COMPOSITES
Authors:   UAE University, UAE, Elmezayen Youssef , El-Maaddawy Tamer ,   UAE University, UAE
Published: August 2024

Numerical simulation models were developed to explore the nonlinear structural behavior of corroded continuous reinforced concrete (RC) beams repaired with carbon fabric-reinforced cementitious matrix (C-FRCM) composites. To validate the numerical predictions, laboratory tests were conducted on five large-scale continuous RC beams. Numerical and experimental results were represented in terms of the load capacity and deflection response. Numerical results closely matched those obtained from the experiments, with a discrepancy in the load capacity ≤ 13%. The numerical analysis revealed that a 40% cross-sectional loss in the sagging zones due to corrosion caused a 22% reduction in the load capacity, while the beam model with the corrosion in the hogging zone experienced a lower strength reduction of 13%. The C-FRCM repair solution designed in the present study compensated for the initial strength reduction caused by corrosion and restored the original load capacity of the control beam model.
CHARACTERIZATION OF AN IRISH SOURCE OF COAL-FIRED FLY ASH AS A CEMENT REPLACEMENT
Authors:   Technological University Dublin, Ireland, Shaji Nikki Maria , Holmes Niall ,   Technological University Dublin, Ireland,   Collegium Basilea, Basel, Switzerland, Tyrer Mark ,   Technological University Dublin, Ireland,   Collegium Basilea, Basel, Switzerland
Published: August 2024

This paper presents work underway by the authors to characterise the fly ash available from a coal-fired electricity plant on the west coast of Ireland and determine its suitability as a cement replacement. The experimental programme described includes X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses to evaluate the mineralogical composition and chemical properties of the ash. The XRD analysis revealed the presence of various mineral phases in the fly ash while the XRF analysis provided data on the elemental oxide composition to better understand its chemical characteristics. Initial concrete trials included measurements of the compressive and flexural strength.
EFFECT OF CARBONATION RATE OF PORTLAND CEMENT PASTE USING AMINO ACID-BASED MIXTURES
Authors:   Kagawa University, Japan, Takahashi Keisuke ,   Mitsubishi UBE Cement Corporation, Japan, Kouno Takuya ,   Kagawa University, Japan, Okazaki Shinichiro ,   Kagawa University, Japan
Published: August 2024

Carbonation can be a promising process to offset the CO2 emission of cement and concrete production, such as CO2 fixation in the form of calcium carbonates. Various technologies have been developed and launched to immobilise the emitted CO2 into concrete wastes. Use of chemical admixtures such as amines in addition to controlling moisture, temperature, CO2 concentration and pressure can accelerate the carbonation of cement hydrates. In this study, the effect of amino acid-based solution, which is easily available and less expensive, was investigated to enhance the carbonation of hardened Portland cement pastes. The results showed that carbonation was enhanced in the pastes coated with the solution of malt extract and soy peptone. The formation of vaterite may become pronounced with the presence of soy peptone. These findings suggest that amino acid-based mixtures can be utilized to accelerate the carbonation of hardened cement concrete and improve the efficiency of CO2 fixation.
A FUNDAMENTAL STUDY ON ESTIMATION OF RELATIVE PERMITTIVITY DISTRIBUTION IN CONCRETE USING DATA ASSIMILATION
Authors:   Hosei University, Japan, Kenmoku Shunsuke , Yamamoto Yoshihito ,   Hosei University, Japan, Sonoda Jun ,   Sendai National College of Technology, Japan
Published: August 2024

We proposed a method for estimating the inhomogeneous permittivity distribution inside concrete by applying the ensemble Kalman filter, one of the data assimilation methods, to the Finite-Difference Time-Domain (FDTD) method. Since no previous studies have applied data assimilation to FDTD simulations of electromagnetic wave propagation problems, the applicability of the proposed method is investigated in this study through numerical experiments using a simple model. Specifically, a simulation of a radar test was performed on a simple concrete model consisting of mortar and aggregate phases, and data assimilation experiments were conducted using simulated observation data while varying the number of aggregates and the number of observation points. Data assimilation experiments were conducted using simulated observation data. The results showed that even though there was only one observation point, the relative permittivity of multiple aggregates in the interior could be well estimated by targeting the radar up to the movement of the radar.
INVESTIGATION OF MACHINE LEARNING METHOD WITH GENERALLIZATION PERFORMANCE FOR AUTOMATIC HAMMERING TEST
Authors:   ETEC Engineering Inc., Japan, SHIMBO Hiroshi , HASEGAWA Noboru ,   National Institutes for Quantum Science and Technology, Japan, MIZOBUCHI Toshiaki ,   Hosei University, Japan, OZEKI Tomoko ,   Tokai University, Japan, NOJIMA Jun-ichiro ,   J-POWER Design Co., Ltd., Japan, NAKAMURA Hikaru ,   Nagoya University, Japan, TOMOTO Satoshi ,   CTI Engineering Co., Ltd., Japan
Published: August 2024

The authors investigated the applicability of machine learning-based hammering test quantification methods to laser hammering systems. This method quantitatively evaluates the degree of defects using an anomaly detection technique with CNN (Convolutional Neural Network) features extraction from the imaged hammering sound. The quantitative evaluation and generalization performance for the conventional human hammering test sound　were examined. The laser hammering system applies a high-power laser beam to the concrete surface for an extremely short period of time creating a physical impact. This technology enables hammering tests remotely and automatically. As a result of the study, it was shown that capability of quantitative evaluation of the degree of defects up to around 15mm depth using laser hammering sounds. The capacity may be modifiable with the system parameters.
OBSERVATION OF ASR EXPANSION CRACKS INSIDE CONSTRAINED MORTAR CYLINDER USING X-RAY CT
Authors:   Kindai university, Japan, FUMOTO Takayuki , KIKUCHI Shintaro ,   Graduate school of Kindai university, Japan, MIKATA Yasuhiro ,   Osaka Institute of Technology, Japan
Published: August 2024

In actual structures, the shape of cracks due to ASR varies three-dimensionally depending on the restraint conditions. This results in anisotropic stress transfer mechanisms inside the structure. Therefore, it is necessary to characterize the cracks due to ASR inside the structure under restraint to properly calculate the bearing capacity of the structure after deterioration. In this study, internal deformation measurements using the X-ray CT method were carried out inside a mortar cylinder specimen with reactive fine aggregate restrained under three conditions: unconstrained, vertically constrained, and horizontally restrained. The results showed that in the case of unrestrained and vertically restrained specimens, longitudinal cracking occurred on the sides, from which water vapor infiltrated, and internal expansion caused an increase in cracking deeper than 20 mm from the sides. In the horizontally restrained case, internal expansion was more uniform, and expansion could be greater than in the unrestrained case.
TEMPERATURE VARIATION ANALYSIS INSIDE CONCRETE DURING FREEZING AND THAWING BY HYDROTHERMAL COUPLED ANALYSIS
Authors:   Yachiyo Engineering Co., Ltd., Japan, Ito Hitoshi , Mizobuchi Toshiaki ,   Hosei University, Japan
Published: August 2024

Among the 700,000 existing Japanese bridges, many were deemed to require repair after bridge inspections. However, Japanese municipalities do not have sufficient time or budget resources, limiting their potential for bridge maintenance. To address this problem, the author proposes a method that uses Infrared Rays for observational maintenance. This method can be used to estimate the corrosion of reinforcing bars inside a structure based on the difference in the rate of surface temperature increase associated with heat dissipation after the structure surface is cooled with dry ice. In laboratory experiments, the authors confirmed that the concrete surface temperature increase rate differed depending on whether the reinforcing bars inside the structure were corroded. Therefore, in this paper, the analysed result of the temperature change inside the concrete when the moisture inside the concrete freezes and thaws and a parametric study based on the results are also presented.