bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Persuasion Strategies in President Biden's Speech at the Climate Change Conference (UN COP27)
Authors: Mouad Mohammed Al-Natour  , Shafiq Banat  , Mehiar Fawwaz Bani Mousa
Published: January 2025

In recent years, climate change speeches have become increasingly significant, especially in high-profile international summits like the Conference of Parties (COP). This study aims to analyze US President Joe Biden's persuasion strategies that were utilized in his speech at COP27. Cialdini's model (2009) of persuasion is adopted to analyze the persuasion strategies overwhelmingly. Qualitatively, observation and memo methods are used to collect the data from Joe Bidin speech which was uploaded on the White House website (White House, 2022). The objectives of this study are expected to be achieved in two sections. Firstly, identifying the types of persuasion strategies that were used by President Joe Biden. Secondly, an in-depth analysis of persuasion strategies will be conducted to find out the preferred persuasion strategy that he utilized.
Non-invasive acupoint stimulation as a complementary therapy for fatigue in hemodialysis patients: A systematic review
Authors: Susanto Gunawan , Upoyo Arif Setyo
Published: January 2025

Background: Patients with chronic kidney disease (CKD) undergoing hemodialysis often experience complex and variable fatigue, which significantly impacts their quality of life. Several factors can cause this fatigue, including the dialysis procedure itself and conditions such as depression, anemia, sleep disorders, and restless leg syndrome. Non-pharmacological methods, such as non-invasive acupoint stimulation, have been used to manage fatigue. However, a systematic review of the literature is needed to determine the effectiveness of this approach.
Purpose: To evaluate the effectiveness of non-invasive acupoint stimulation as a complementary therapy in reducing fatigue levels in patients undergoing hemodialysis.
Method: The databases Google Scholar, ResearchGate, and ProQuest  were used to identify English-language research publications from 2013 to 2024. These publications included two from Iran, one from Turkey, one from India, one from Korea, and two from Taiwan. The selection of publications followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Quality evaluation was conducted using the Joanna Briggs Institute (JBI) Critical Appraisal Skills Program.
Results: Findings indicate that all evaluated non-invasive acupoint stimulation methods significantly reduced fatigue. Electrical stimulation techniques, including electro-stimulation and Transcutaneous Electrical Acupoint Stimulation (TEAS), demonstrated consistent effectiveness. Manual acupressure and auricular acupressure also showed significant improvements in fatigue levels. Additionally, radiation stimulation using far-infrared light yielded promising results. Variations in the number of stimulation points, session duration, and total intervention length still produced significant reductions in fatigue, suggesting that non-invasive acupoint stimulation methods can be effective despite methodological differences.
Conclusion: Non-invasive acupoint stimulation methods show great potential in managing fatigue in hemodialysis patients. Despite methodological variations, all studies reported significant fatigue reductions, supporting the integration of non-invasive acupoint stimulation methods into clinical practice to improve patients' quality of life. Further research is needed to develop intervention protocols and confirm these findings.
Nurses' perspectives on culturally sensitive maternity care in hospital settings
Authors: Ulfah Diana , Hermayanti Yanti , Maryati Ida , Widiasih Restuning , Natasya Windy , Solehati Tetti , Sasmito Priyo
Published: January 2025

Background: Differences in cultural backgrounds between healthcare workers and patients can lead to misunderstandings and cultural shock for patients. Nurses must navigate these situations to provide services that prioritize attentiveness, mutual respect, and cultural sensitivity, ultimately improving patients' health outcomes. Nurses play a critical role in delivering appropriate care, particularly when cultural practices may pose risks to maternal health during childbirth. Therefore, understanding the cultural perspective is essential for nurses in providing effective maternity care.
Purpose: To explore nurses' perspectives on providing culturally sensitive maternity care to mothers during childbirth within the hospital setting.
Method: A qualitative research design with a descriptive phenomenological approach was employed. Twelve informants participated in the study to ensure data saturation. Semi-structured interviews were conducted through face-to-face sessions, Zoom meetings, and audio recordings. Data were analyzed using the Colaizzi method.
Results: Three key themes emerged from the analysis: (1) Culturally sensitive assessments were primarily focused on spiritual and social aspects; (2) Implementation of cultural sensitivity was achieved through interprofessional collaboration, education, and direct care; (3) Improvements in culturally sensitive care were identified as necessary, including policy development, additional human resources, and health education guidelines.
Conclusion: Nurses' perspectives on culturally sensitive maternity care indicate a lack of a comprehensive cultural approach in current practices. Enhancing maternity nurses' competencies through targeted training on cultural assessments is essential to support high-quality maternity care that respects and integrates cultural considerations.
Assessment of Heavy Metal Content in Chicken Eggs and Evaluating Associated Health Risks
Authors: Shahriar S. M. S. , Rabby M. F. , Akhtar M. M. , Dipti S. , Kulsum U. , Hossain M. S. , Salam S. M. A.
Published: January 2025

Chicken eggs are an excellent source of vital nutrients, such as vitamins, minerals, carotenoids, proteins, and healthy fats. Though it can significantly fulfil the nutritional needs of adults and children, the contamination of heavy metals may cause subsequent toxicity to our bodies. The ultimate goal of the experiment is to analyze the amounts of heavy metals (Pb, Cr, Ni, Zn, and Cu) in eggs and their health risk assessments. After the egg samples were processed using a di-acid digestion technique, an AAS was used to evaluate the samples. Here, only the concentrations of Pb and Cr exceeded the maximum permissible range established by WHO/FAO. According to the health risk assessment, the metals in the study (except for Pb) did not individually represent a concern by the target hazard quotient and estimated daily intake. Pb and Cr had threshold carcinogenic risks because their CR values ranged from 10-4 to 10-6. Consumers of Ni, which has a CR > 10-4, are thought to pose a carcinogenic risk to adults and children. The quantities of zinc and copper in all examined samples were deemed acceptable for human ingestion. This research provides legislators with precise and trustworthy information to enhance food safety regulations and mitigate public health threats.
Insights into Soft Semigraphs: AND & OR Operations and Measurement Perspectives
Authors: George B. , Thumbakara R. K. , Jose J. , George S. P.
Published: January 2025

Molodtsov pioneered the concept of soft sets, offering a method to classify elements of a universe based on a specified set of parameters. This approach serves to model vagueness and uncertainty. Semigraphs are a generalized form of graphs introduced by Sampathkumar. The integration of soft set theory into semigraphs led to the creation of soft semigraphs. Due to its adeptness in handling parameterization, the field of soft semi-graph theory is rapidly evolving. This study introduces AND and OR operations within soft semi-graphs and explores some of their characteristics. Furthermore, we present various soft semi-graph measurements, such as distance, radius, diameter, and center.
Evaluation of the Antimicrobial Potential of Pleurotus ostreatus Extracts
Authors: Neha Y. D. , Girish K.
Published: January 2025

Antimicrobial activity of Pleurotus ostreatus was studied in vitro using its aqueous and methanolic extracts, against nine human pathogenic bacteria (MTCC cultures) such as Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus pneumoniae - Gram positive bacteria; Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Proteus vulgaris, Salmonella enterica ser. typhi and Shigella flexneri - Gram negative bacteria. Antifungal potential was screened against phytopathogenic fungi like Alternaria sp., Aspergillus sp., Fusarium sp. and Helminthosporium sp. The P. ostreatus aqueous extract failed to show growth inhibitory effect against any of the human pathogenic bacteria or phytopathogenic fungi studied. The P. ostreatus methanolic extract exhibited significant inhibition of all the bacteria tested at higher concentrations of 2000, 3000, 4000 and 5000 ppm. But, even P. ostreatus methanolic extract could not inhibit the growth of phytopathogenic fungi studied, at any of the concentrations screened. P. ostreatus methanolic extract was found to have phytochemicals such as alkaloids, flavonoids, phenols, saponins, steroids, tannins, and terpenoids. The results of present studies reveal the antibacterial potential of Pleurotus ostreatus, which could be further evaluated to obtain potent antibacterial bioactive principles for new drug development.
Palaeomagnetic Polarity of the Deccan Basalt Lava Flows, Exposed Around Eastern Part of Amravati City, Central India: Implications of N-R Sequenceequence
Authors: Deshmukh M. S. , Deshmukh M. M. , Khadri S. F. R.
Published: January 2025

Basalt preserve palaeomagnetic record, essential for the correlation of the lava flows which is important to establish flow stratigraphic sequence. The present study encompasses, palaeomagnetic polarity of the Deccan basalt lava flows, exposed in Chhatri Talao hill (part of Pohra hill ranges), due east of Amravati city, Maharashtra State, India. During the present study, flow mapping was carried out with collection of basalt rock samples for palaeomagnetic investigation. Geological field results indicate exposure of three basalt lava flows between altitude of 365 to 435 meter (amsl), which are (i) lower flow-I: fine to medium grained, mafic plagioclase microphyric basalt; (ii) middle flow-II: coarse grained, mafic plagioclase phyric basalt and (iii) upper flow-III: fine to medium grained, mafic plagioclase microphyric basalt. Results also indicate, ‘Normal’ polarity of upper two lava flows (flow-II and flow-III), exposed at an altitude of 427-440 meter and 398-427 meter (amsl), and ‘Reverse’ palaeomagnetic polarity by the lower flow (flow-I) at an altitude of 380-398 meter (amsl). Thus, present study, can be useful to correlate eastern basalt lava flows with other parts of the Deccan basaltic terrain. This study can be useful to determine the palaeo-latitudes of eastern Deccan basalt lava flows.
Pondering the Dynamicity of tertiary level EFL Learners’ Motivation and Emotion and the Determinants of their Dynamicity with a special emphasis on Directed Motivational Currents (DMCs)*
Authors: Gümüş Özge , Erten İsmail Hakkı
Published: January 2025

This research holds substantial scholarly importance in understanding the intricate interplay between EFL learners' motivation and emotion. Utilizing a complex dynamic systems framework, this research systematically investigates the fluctuation patterns and factors that influence variations in motivation and emotion within the tertiary educational context. By using Retrodictive Qualitative Modelling (Dörnyei, 2014), this study identified eight distinct EFL learner archetypes. The data collected through as motigraphs, semi-structured interviews, reflective journals, and follow-up interviews demonstrated a diverse range of motivational dynamics seen in EFL learners, including those who are highly motivated by specific goals (referred to as Directed Motivational Currents or DMC), persons who display features associated with DMC, and individuals with different levels of motivation devoid of a DMC. The analysis of qualitative data revealed distinct and context-specific patterns of motivation and emotion within participants' motivational systems, yet these patterns were influenced by a detectable set of parameters. The implications of this study have relevance in both theoretical and instructional settings, suggesting the need for more empirical studies in this field. This detailed comprehension adds to the greater academic discussion on motivation and emotion in EFL acquisition, providing insight into the dynamic nature of learners' motivational experiences.
Bruno Catalano’nun Heykellerinde Gestalt’ın “Tamamlama” İlkesinden ve Gösterge Biliminden Yola Çıkarak “Göç” Olgusuna Ulaşmak
Authors: Uzun Aydın Derya
Published: January 2025

Öz: Bu çalışmamız göç temasını, modern dünyanın çağdaş heykel sanatçısı Bruno Catalano’ya(1960-Fas) ait “eksik heykeller” olarak da tanımlanan heykellerin, göçün sanatsal izdüşümleri ile yorumlanması ve Gestaltın“algıda tamamlama” kuramından da faydalanılarak disiplinler arası girift bir düzlem oluşturulmasıyla analiz edilerek, göç kavramına faklı bir perspektifle yaklaşılması amacı taşımaktadır. Araştırmamızın orijinini oluşturan “göç” olgusu incelenmeye çalışılmış, sanatçının yaptığı heykel çalışmaları birer “gösteren” olarak, gösterge bilimin inceleme alanından faydalanılarak ikonografik kısa betimlemelere ulaşmamızı sağlamıştır. Onun çalışmaları içerisinde göçü sanatsal yönleri ile en iyi aktaran heykel örnekleri, bir dizi seri çalışma olarak bilinen “Gezginler” serisidir. Elbette temasal olarak göç, birçok literatür taramasına ve sanatsal anlatıma konu olmuştur ancak burada bizlerin amacı, sanatçı üzerine yapılan tek ve ayrı bir çalışma örneği oluşturmak ve sanatçı sayesinde “eksik heykeller” tabirine de vurgu yaparak yeni bir anlatı oluşturma gayesi taşımaktadır. İşte bu noktada da Gestalt ve kuramları çalışmamıza farklı bir derinlik kazandırarak konumuza en uygun ilke olan “tamamlama” ilkesinden ya da yönteminden, kazanımlar elde edilmesini sağlamıştır. Bu sayede çalışma, yalnızca göçün sanatsal eserlere yansıması gibi tek bir koldan değil, farklı yöntem, ilke ve anlatım ifadeleri ile de zenginlik kazanmıştır.
A decision support system to predict mortality events in finfish aquaculture
Authors: Howarth LM , Knight BR , Symonds JE , Waddington Z , Davidson I
Published: January 2025

The aquaculture industry can be impacted by mortality events triggered by marine heatwaves, pathogens, and other environmental factors. Aquaculture managers would benefit from advanced warning of mortality events so they can make decisions to maximise production and profitability. To help monitor fish health and performance, finfish farms are often equipped with an array of cameras and environmental sensors. However, analysing and interpreting all this information can be difficult. Decision support systems (DSSs) can help by simplifying multiple data sources into a single output for quick interpretation and action. Here, we present a DSS capable of providing salmon farmers with 4 wk warning of an impending mortality event. This DSS was trained on a suite of data routinely collected by New Zealand salmon farmers and provides an alert if weekly mortality is predicted to exceed 0.5%. In the final model, present mortality, water temperature, and standardised feeding rate were all found to be significantly correlated with the probability of a future mortality event. The model performed well when tested on data not included in the model-building process, suggesting that the DSS could be useful to farm managers. This study shows that even limited information can be used to construct a DSS capable of providing some advanced warning of elevated mortality risk. Given the ease with which DSSs can be adapted to ingest and predict other parameters, we see strong potential for future development and adoption of these tools by the aquaculture industry and other sectors.
Presence or absence of a planktonic egg and larval stage affects the intertidal recruitment of Littorina species (Gastropoda) during very strong El Niño events
Authors: Boulding EG
Published: January 2025

Life history traits affecting dispersal ability could affect species’ responses to climate change. Size-specific abundances of 4 NE Pacific Littorina snail species (2 with planktonic eggs and larvae [planktonic development, PD] and 2 with direct development [DD] from attached egg masses) were compared on 2 rocky intertidal sites near Bamfield on Vancouver Island, British Columbia, Canada, between 1994 and 2021. Two very strong El Niño-Southern Oscillation events (1997/1998 and 2015/2016) were followed by large, significant increases in recruitment of 2 PD species. By contrast, the juvenile recruitment of the common DD species showed varied responses to the first event and a large, significant decrease during the second event. Four hypotheses explaining the effect of the developmental mode on recruitment after very strong El Niño events were evaluated. Two of these hypotheses, (H1) interspecific competition and (H2) selective predation of the thin-shelled DD species by a temporarily invading lined shore crab from southern Oregon, USA, were rejected. Alternative hypotheses were that the larval supply and/or juvenile survival of the PD species increased because of (H3) higher summer sea surface temperature (SST) or (H4) stronger winter poleward currents and higher minimum winter SST. H4 was strongly supported by the significant positive ‘slope’ coefficients for the covariate ‘previous February SST’ within multivariate autoregressive state-space models of the July and December juvenile PD count anomalies. The northward winter Davidson surface current is faster and warmer during very strong El Niño events, which may increase the larval transport and subsequent intertidal recruitment of the PD species.
PENGARUH STRATEGI PEMASARAN SELAMA MASA PANDEMI TERHADAP UMKM COFFE SHOP (Studi Pada Kedai Babaturan di Kecamatan Cisayong)
Authors: Nurwanti Siti , Yuliana Yuliana , Sartika Sri Hardianti
Published: January 2025

Penerapan strategi pemasaran UMKM di sebuah bisnis coffe shop, dengan sasaran pengamatan pada Kedai Babaturan sebagai coffe shop yang tetap eksis pada era pandemi seperti ini, Kedai Babaturan dipilih sebagai sasaran penelitian, mengingat coffe shop ini bisa bertahan dalam kondisi ekonomi yang tidak stabil seperti sekarang ini. Penelitian ini saya lakukan untuk mengetahui strategi pemasaran yang dilakukan Kedai Babaturan. Hasilnya, diperoleh bahwa dalam sebuah pemasaran produk ini ada beberapa aspek yang menunjang akan keberhasilan Kedai Babaturan yaitu sasaran konsumen, promosi, brand, tempat, harga dan juga fasilitas. Hal ini yang di perhatikan Kedai Babaturan dalam menjalankan strategi pemasaran nya mengingat Kedai Babaturan berhasil membuka cabang nya dikala massa pandemi seperti ini. Itulah sebabnya, strategi pemasaran sangatlah penting didalam dunia bisnis apalagi UMKM. Penelitian ini juga bisa dijadikan referensi bagi usahawan yang baru memulai karir bisnisnya. Metode untuk mengetahui data ialah observasi secara langsung, dalam memperoleh data ada beberapa acuan yang saya perhatikan yaitu efektivitas dan strategi pemasaran.
Pengaruh perputaran piutang dan struktur hutang terhadap profitabilitas
Authors: Sulastri Sulastri , Misra Misra
Published: January 2025

Penelitian ini bertujuan untuk mengetahui pengaruh perputaran piutang dan struktur hutang terhadap profitabilitas pada perusahaan tekstil dan garment yang terdaftar di Bursa Efek Indonesia (BEI) tahun 2014-2020. Jenis penelitian ini termasuk dalam penelitian kuantitatif. Populasi penelitian ini adalah perusahaan tekstil dan garment yang terdaftar di BEI periode 2014-2020. Teknik pemilihan sampel yang dilakukan untuk pengambilan sampel penelitian ini menggunakan purposive sampling dengan jumlah sampel penelitian sebanyak 13 perusahaan. Periode pengamatan pada penelitian ini selama 7 tahun sehingga total sampel adalah 91. Teknik analisis data menggunakan program SPSS versi 23.0. Hasil didapat perputaran piutang berpengaruh signifikan secara negatif terhadap profitabilitas dengan t hitung > t tabel (2,504>1,991) dan signifikansi 0,014 (0,014<0,05). Struktur hutang tidak berpengaruh signifikan terhadap profitabilitas denga t hitung < t tabel (1,321<1,991) dan signifikansi 0,191(0,191>0,05). Hasil uji F atau uji simultan menunjukkan bahwa secara bersama-sama perputaran piutang dan struktur hutang berpengaruh signifikan terhadap profitabilitas dengan nilai signifikansi 0,035 (0,035<0,05). Dari hasil koefisien determinasi menunjukkan bahwa hubungan antar variabel bebas dan variabel terikat masih lemah.
DESIGN OF LOW VOLUME CONCRETE ROADS
Authors: Huber Robert G.
Published: January 2025

This article by Robert G. Huber explores the evolution and benefits of low volume concrete roads, focusing on the pioneering use of the slipform paving method in Iowa. It traces the origins back to 1946 when James W. Johnson conceptualized a machine that laid concrete without the need for side forms. Successive developments led to the creation of more advanced machines, with the first practical applications on county highways by the late 1940s. By the 1950s, the method had spread beyond Iowa, as other states and equipment manufacturers recognized the efficiency and cost-effectiveness of slipform paving. Notably, the slipform paver underwent significant improvements, facilitating its adoption for wider use. The paper details the specific adjustments in design and operation made in Iowa, such as the adoption of Type B concrete with varying cement content suitable for local conditions, and adjustments to subgrade preparation to enhance durability and performance. It also discusses the economic benefits, highlighting significant cost savings over traditional paving methods, alongside the reduced maintenance costs observed in Washington County. Furthermore, Huber elaborates on the broader adoption of slipform paving, predicting its dominance in the paving industry. The narrative is supported by data on road paving activities and costs over the years, providing a comprehensive view of the method’s impact on road construction in Iowa. This historical and technical account not only underscores the innovation's practicality but also its role in advancing road construction technology, making a case for its continued use and development. (Abstract generated by AI tool ChatGPT 4)
ECONOCRETE IN PAVEMENT DESIGN
Authors: Yrjanson W. A.
Published: January 2025

This paper outlines the development and utilization of Econocrete, a form of portland cement concrete specifically designed for paving applications where conventional aggregates are scarce or do not meet typical quality standards. Initiated by the American Concrete Paving Association's Technical Subcommittee on Materials and Mix Design in 1973, Econocrete aims to optimize the use of locally available aggregates that are typically deemed unsuitable for standard concrete due to inferior quality. Econocrete leverages such aggregates in the base course of composite pavement structures while reserving higher quality aggregates for the surface course, which is more exposed to wear and environmental conditions. The study describes various test programs conducted across states like Florida, Georgia, South Carolina, and Iowa, evaluating different aggregate types that do not meet the conventional standards for pavement concrete but could be viable for Econocrete. This includes aggregates with high fines content, poor abrasion resistance, and others typically excluded from standard use due to performance issues at the pavement surface. Through comprehensive research and testing, the subcommittee developed mix designs that address the specific environmental and service requirements of the regions, allowing for economic and ecological benefits by reducing transportation costs and using less desirable local resources effectively. The paper also explores the broader applications of Econocrete in constructing durable and cost-effective pavements, subbases, and shoulders, potentially increasing the lifespan and performance of roadways while accommodating various traffic volumes and environmental conditions. This innovation not only offers a practical solution to the diminishing supply of conventional aggregates but also represents a significant advancement in sustainable pavement technology. (Abstract generated by AI tool ChatGPT 4)
EUROPEAN CONCRETE ROAD STANDARDS AND PRACTICES
Authors: Sharp Raymond
Published: January 2025

The scientific article "European Concrete Road Standards and Practices" by Raymond Sharp provides a comprehensive overview of the current standards and practices in the construction of concrete roads across Europe, focusing on twelve countries: Austria, Belgium, Czechoslovakia, Denmark, France, Great Britain, Italy, the Netherlands, Spain, Sweden, Switzerland, and West Germany. The research synthesizes data from the Permanent International Association of Road Congresses (PIARC) and the European Cement Association, including detailed synoptic tables prepared for previous European symposia on concrete roads. This study delves into the various factors influencing pavement design, including traffic levels, sub-grade strength, and pavement materials, discussing the complexities of predicting future traffic and the insensitivity of pavement costs to small traffic variations. It examines the philosophical and economic decisions that guide pavement thickness and highlights the standardization in pavement design across different nations, emphasizing the small changes in design thickness due to the proven success and economic efficiency of existing systems. Furthermore, the paper explores the influence of non-technical factors such as governmental policies and competition between construction methods on pavement design. It also discusses the impact of local material availability and construction practices on the cost and quality of road construction. The research concludes that while concrete pavements generally perform well and offer long life spans, there are multiple viable approaches to pavement design influenced by local conditions and historical practices. It suggests that imposing a uniform design approach across different environments and traditions is impractical, advocating for flexible, context-specific solutions in pavement engineering. (Abstract generated by AI tool ChatGPT 4)
STEEL FIBROUS CONCRETE FOR AIRPORT PAVEMENTS
Authors: Parker Frazier , Rice John L.
Published: January 2025

In the past several years, considerable interest has been generated in the use of steel fibrous concrete for pavements. Steel fibrous concrete is a composite material consisting of a concrete matrix containing a random dispersion of small steel fibers. The introduction of the fibers imparts to the concrete matrix certain characteristics, such as resistance to spalling, the ability to sustain load after initial cracking, and the ability to keep cracks tightly closed, which improve its performance compared to plain or conventionally reinforced concrete pavement. This paper contains a discussion of the properties of steel fibrous concrete, procedures for designing and constructing steel fibrous concrete airport pavements, and applications on airports.
THE INFLUENCE OF CEMENT TREATED SUBBASES ON THE DESIGN OF AIRPORT P.C. CONCRETE PAVEMENTS
Authors: Domenichini Lorenzo , Moraldi Giorgio
Published: January 2025

This study explores the influence of cement-treated subbases (CTS) on the design of airport Portland cement concrete (P.C.) pavements through both empirical research and theoretical modeling. Specifically, the research investigates how various characteristics of CTS, including modulus values and interface conditions (frictional properties), impact the performance and structural integrity of concrete slabs under airport pavement conditions. Using linear multilayered elastic models and finite element analysis, the study contrasts the impacts of different interface conditions (full friction versus no friction) and examines the effect of CTS thickness and modulus on stress distribution and deflection in the pavement system. The results from the modeling show that the presence and condition of the CTS significantly affect pavement performance, indicating specific thresholds for CTS thickness and stiffness to optimize pavement durability and minimize stress. These findings underscore the importance of meticulous design considerations in the construction of airport pavements to enhance their longevity and functionality. This research provides a comprehensive analysis that could guide future design improvements in airport pavement construction, particularly concerning the use of cement-treated subbases. (Abstract generated by AI tool ChatGPT 4)
A COMPUTER PROGRAM FOR SLABS WITH DISCONTINUITIES ON LAYERED ELASTIC SOLIDS
Authors: Chou Y. T. , Huang Y. H.
Published: January 2025

A finite element method programmed for a high­ speed computer is presented. The method is based on the classical theory of thin plate. The program is developed for subgrade soil represented as a linear layered elastic solid. Any number of layers can be accommodated. The program is capable of analyzing stress conditions in concrete pavements with the load transfer in the joint, as well as in the supporting subgrade soil, subjected to loads and temperature warping. Multiple-wheel loads can be input and the number of wheels is not limited. Because of the large computer storage space required, the program can handle only two slabs, except for the special option where a four-slab pavement system is loaded symmetrically at the pavement's center. At the joint, the progam considers only the shear transfer and assumes the element transfer to be zero. The results computed using the program were compared with stress transfers across the joint measured in airfield test pavements. The comparisons were very favorable.
CONCRETE OVERLAYS FOR CONCRETE AND ASPHALT PAVEMENTS
Authors: Lokken Edwin C.
Published: January 2025

Concrete resurfacing of worn concrete pavements has been a fairly common practice in the United States for more than 60 years. Since the mid- 1950's new construction on the Interstate System has taken precedence, and fewer concrete resurfacing projects were built. With the emergence of the 3R program of pavement rehabilitation, restoration and resurfacing, new interest is being shown in the use of concrete as a more durable and permanent resurfacing material. A recent survey (1977) of 39 concrete resurfacing projects in the U.S. with plain or conventionally reinforced designs showed them ranging from 4 to 36 years of age, with an average age of 25 years. Their designs varied considerably; more than a third of the projects were plain concrete without reinforcement or dowels. The results of a 1975 survey of 23 CRC projects are reviewed and brought up to date with 1980 condition data. Designs using a thin layer of concrete bonded to the old slab have been employed as a resurfacing method in the U.S. for many years. The results of bridge deck resurfacing using a dense concrete mix have been particularly successful. The resurgence of interest in concrete pavement resurfacing has brought new emphasis on techniques and equipment to adapt this method to the level of other full-scale high speed paving operations. Current concrete resurfacing activities in the U.S. show a noticeable trend toward the use of concrete overlays to restore worn bituminous pavements.
CRCP DESIGN BASED ON THEORETICAL AND FIELD PERFORMANCE
Authors: McCullough B. F. , Cawley Martin L.
Published: January 2025

This paper provides a comprehensive overview of the design procedures for Continuously Reinforced Concrete Pavement (CRCP) based on theoretical studies and empirical field performance data. As CRCP becomes a preferred choice for pavement due to its durability and reduced maintenance, understanding the nuances of its design becomes crucial for civil engineers. This study synthesizes the historical and recent advancements in CRCP design, focusing on the optimization of pavement thickness and reinforcement to adapt to varying traffic and environmental conditions. The article elaborates on the evolution of CRCP from its early experimental applications to its current status where it has been adopted in various states across the U.S., with Texas, Illinois, and Mississippi leading in implementation. The research discusses the influence of factors such as subbase stability, reinforcement placement, and concrete quality on pavement performance. Various state practices are examined to identify the best and poor practices, with detailed case studies from Texas and Illinois providing insights into the effectiveness of different design methodologies under diverse environmental conditions. Key innovations in pavement design are highlighted, including modifications to the thickness determination charts to accommodate new loading conditions and the introduction of design nomographs for improved reinforcement calculations. Theoretical modeling and empirical data are used to refine CRCP design standards, aiming to enhance pavement serviceability while minimizing construction and maintenance costs. The findings from this paper are intended to guide future CRCP constructions, ensuring that these pavements meet the high demands of modern transportation infrastructure. (Abstract generated by AI tool ChatGPT 4)
DESIGN OF AIRPORT PAVEMENTS AS AFFECTED BY LOAD TRANSFER AND SUPPORT CONDITIONS
Authors: Barenberg Ernest J. , Arntzen Donald M.
Published: January 2025

Current FAA Design Criteria for major airports are based on the assumption of edge loading conditions, with an assumed load transfer of 25 percent, and a stabilized subbase equal in thickness to the thickness of the PCC slab. This paper examines the validity and cost effectiveness of these requirements. Theoretical analyses and results from field tests confirm that it is more economical to develop structural capacity of the PCC pavement by increasing the thickness of the PCC slab and reducing the thickness of the stabilized subbase. It is shown that three inches of added thickness in the PCC slab will reduce the deflection of the pavement, the stresses transmitted to the subgrade, and the stresses in the PCC slab more than 12 to 18 inches of stabilized subbase and at a lower initial cost. It is also demonstrated that effective load transfer is needed to prevent excessive corner deflections of PCC slab under the wide bodied aircraft gear loadings. Large diameter dowels and heavy tie bars are used at the load transfer mechanisms. Significant savings were demonstrated using these approaches to pavement design over the thicknesses obtained using the design recommendations in the FAA Advisory Circular.
DESIGN PROCEDURE FOR CRCP BASED ON THEORETICAL CONSIDERATIONS AND SERVICE BEHAVIOUR
Authors: Haber Edwin , Cruickshank John
Published: January 2025

This paper outlines the growth in the use of concrete pavements in Australia in recent years, with particular emphasis upon the most populous State of New South Wales. The development in the use of CRCP is traced and its behaviour recorded, culminating in the adoption of a simplified design procedure based upon the environmental cracking approach necessitating some assumptions pertaining to bond strength. Consideration is also given to the specification and control of CRCP construction, including the stipulation of an upper limit on concrete strength.
MECHANISTIC OVERLAY DESIGN PROCEDURES FOR RIGID PAVEMENTS
Authors: Majidzadeh Kamran , Ilves George J. , May Richard W.
Published: January 2025

The review of currently available overlay design methods indicates that these may be grouped in three categories: those based on a visual condition rating, those using NDT deflections and empirically derived relationships between allow­ able deflection and overlay needs, and semi­ rational procedures using stress analysis. The more promising of these procedures were subjected to detailed analysis and compared using data from a variety of projects. The result of this analysis show that none of the existing models is very satisfactory and that a new overlay design procedure is needed, This paper presents the formulation of a method that attempts to overcome the difficulties and limitations of current methods. The proposed method utilizes both NDT and visual condition evaluation as well as limited destructive and laboratory testing to evaluate existing pavement condition. A coupled FEM-multilayer elastic subgrade program is used in stress analysis, and the amount of overlay is determined based on limiting formation of load-induced fatigue cracking. This program will be used in a re-examination of the MSHO Road Test data as well as other available performance data to identify and correlate available field data with a performance distress function. Reflection cracking analysis incorporating load-induced shear as well as temperature induced stresses (both horizontal and curling stresses) will be used to minimize the probability of reflective crack formation.
RECYCLING PORTLAND CEMENT CONCRETE
Authors: Yrjanson William A.
Published: January 2025

In a growing number of areas in the United States, it is becoming increasingly advantageous to recycle old portland cement concrete. The momentum for recycling has been primarily generated in areas where there is a shortage of, or a complete lack of, supplies of aggregates meeting present day quality standards. Another equally important factor is the problem of solid waste disposal, particularly in urban areas. A reduction in construction costs and conservation of energy have also sparked interest in recycling. Under the recycling concept, existing roadways, airport pavements or any suitable waste concrete becomes a readily available source for producing aggregates. Laboratory research and experience at several recent projects have proven that recycling concrete into aggregate for use in new concrete is feasible and should be considered whenever quality aggregates are not locally available or waste disposal of concrete rubble is costly.
STATUS AND DEVELOPMENTS IN THE CONSTRUCTION OF PRESTRESSED CONCRETE RUNWAYS IN EUROPEAN AIRPORTS
Authors: Flunker Fritz
Published: January 2025

Various methods for prestressing concrete pavements and their performances over the years are evaluated. The article gives the design criteria for prestressed concrete pavement and then recommends construction principles and procedures.
THE APPLICATION OF PRESTRESSED CONCRETE TO THE CONSTRUCTION OF AIRFIELD PAVEMENT
Authors: Van Noortwijk H. , V.d. Meent A.
Published: January 2025

In this paper the following subjects are presented: I. The History of the Airport. 2. The choice of prestressed concrete for airport pavement. 3. Soil conditions and foundation. 4. Prestressed concrete constructions. 5. Further possibility of constructing the expansion joint between two slabs. 6. Further developments. 7. Design criteria. 8. Tests. 9. Experience and maintenance. 10. Construction and maintenance costs.
CONCRETE PAVEMENTS, NOW AND TOMORROW
Authors: Hutchinson Ronald L.
Published: January 2025

The paper "Concrete Pavements, Now and Tomorrow" by Ronald L. Hutchinson provides an extensive review of concrete pavements in the context of the United States' infrastructure. Hutchinson discusses the historical and current usage of concrete in the pavement system, which encompasses highways and civil and military airports, highlighting the importance of concrete due to its frequent selection for heavy loads. The paper emphasizes the need for rehabilitation as the major future construction activity and examines the role concrete pavements will play in this context. The analysis includes a detailed look at existing concrete pavements, their performance under increased traffic and heavier loads, and the challenges they face such as deterioration due to environmental factors and loading conditions. Hutchinson reviews various design methods used over the years, particularly those by the American Association of State Highway and Transportation Officials (AASHTO) and the Portland Cement Association (PCA), and discusses their limitations due to reliance on empirical data or simplistic theories that do not account for all variables affecting pavement performance. Looking forward, the paper forecasts that maintenance and rehabilitation will dominate future efforts rather than new construction. The need for innovative rehabilitation techniques is underscored, considering the aging pavement systems and the continuous increase in traffic volumes and loads. Hutchinson calls for enhanced research into pavement materials, design methodologies, and construction techniques to extend the life of pavements at lower costs and with minimal maintenance. The paper concludes by stressing the importance of a proactive approach to pavement management to sustain economic development and meet future transportation demands effectively. (Abstract generated by AI tool ChatGPT 4)
CONDITION SURVEY OF CONCRETE PAVEMENTS AND ITS EVALUATION
Authors: Fukuda Tadashi , Koyanagawa Masashi , Murai Sadanori
Published: January 2025

Concrete pavements in the Tohoku Region of Japan were surveyed. It is indicated that 25 cm slab thickness has been the mainstream after 1970s and 80 percent of them can last the design service lives of 20 years under daily average volume of 700 to 1400 commercial vehicles per lane. In order to investigate cracking patterns of concretes-labs, multivaliate analysis was employed. ·According to the results of the analysis, slab width and volume of commercial vehicles were the factors greatly affecting cracking patterns of concrete slabs. Taking into account the analytical results, the current design method was modified. The results of the survey agree comparatively well with the results of the calculation by the modified method.
DESIGNING FOR QUALITY, CONCRETE PAVEMENT REHABILITATION AND RECYCLING ON WISCONSIN'S INTERSTATE HIGHWAYS
Authors: Strand D. L.
Published: January 2025

This report presents the concepts, design parameters, and construction aspects of reconstructing 51.5 km. (32 miles) of Interstate 90/94 in Dane and Columbia counties between Madison and Portage, at a cost of 70 million dollars. A main feature of the project is first time"use of all epoxy coated steel in the continuously reinforced concrete pavement. Two major design problems were addressed and solved simultaneously, the problem of highway capacity and that of how best to rehabilitate an aging, 23 year old concrete highway. Except for 6.8 km. (4.2 miles) of existing 23 year old CRCP which was still providing excellent service, the existing (mesh and dowel reinforced) concrete pavement was removed, crushed to meet standard specification coarse aggregates for concrete, and recycled into the new overlay. The principal features of this innovative project are: a third lane was added to both roadways with no increase in existing R/W, existing jointed mesh and dowel pavement was replaced with CRCP, 3.05 meter (ten feet) concrete shoulders were constructed on all sides, all reinforcing steel is epoxy coated, all longitudinal reinforcement was placed on transverse bars on chairs, the existing pavement was recycled into coarse aggregate for the new concrete, existing CRCP and bridges received a bonded concrete overlay, all the new pavement was constructed during the 1984 construction season, both roadways and all interchanges remained open throughout construction.
FINITE ELEMENT ANALYSIS OF SLABS-ON-GRADE USING A VARIETY OF SUPPORT MODELS
Authors: Ioannides A. M. , Thompson M. R. , Barenberg E. J.
Published: January 2025

The Finite Element Method has been a very powerful tool for the analysis of slab-on­ grade type pavements in the last two decades. A number of programs have been developed which treat the slab as an elastic plate and characterize foundation support either as a dense liquid or as an elastic solid. This paper describes the development of an expanded and revised version of ILLI-SLAB, which now incorporates four subgrade idealizations: the Winkler dense liquid, the Boussinesq elastic solid, the stress dependent resilient subgrade and the Vlasov two-parameter foundation. Comparative studies are greatly facilitated and results from numerous runs are presented to illustrate the scope of the program's applicability. The efficient utilization of ILLI­ SLAB is ensured by adherence to guidelines established during several convergence studies described.
NONDESTRUCTIVE AIRFIELD RIGID PAVEMENT EVALUATION
Authors: Bush Albert J. , Alexander Don R. , Hall Jim W.
Published: January 2025

A nondestructive evaluation procedure is presented that has been developed for a variety of NDT equipment. The methodology is based on layered elastic theory and uses a performance model developed previously for airport type loadings. A study was conducted at MacDill Air Force Base to compare evaluation methodologies being used on airport pavements. Data from six different NDT devices is used to evaluate two rigid pavements. Results are presented to illustrate the applicability of this evaluation procedure for those devices. Comparisons of allowable aircraft loads determined from NDT and destructive evaluation procedures are presented.
THICKNESS DESIGN OF CONCRETE RESURFACING
Authors: Tayabji Shiraz D. , Okamoto Paul A.
Published: January 2025

Many miles of the nation's highway system have reached or exceeded their design lives in terms of traffic loading. A large portion of the highway system is being revitalized as part of the federal government's 4R program. The 4R program consists of rehabilitation, restoration, resurfacing, and reconstruction. Because of its cost-effectiveness and functional benefits, resurfacing is and will continue to be an important part of the 4R program. Portland cement concrete has been used to resurface pavements for over fifty years. Concrete resurfacing provides a relatively low maintenance service life. There are basically four types of concrete resurfacing. These are bonded, directly placed, unbonded, and concrete resurfacing over an existing asphalt pavement. concrete resurfacings have been designed in the past by experience or engineering judgment. Recognizing the inherent weaknesses in the existing design procedures, an investigation was sponsored by the Portland cement Association to develop more rational concrete resurfacing design procedures. This paper presents new thickness design procedures for unbonded and bonded resurfacings. The procedures involve a pavement condition survey, non­ destructive load testing at the pavement surface, evaluation of in-situ material properties of the existing pavement, and use of design charts to compute required resurfacing thickness. The unbonded and bonded concrete resurfacing procedures are based on providing a resurfaced pavement that is structurally equivalent to a full depth concrete pavement designed for anticipated future traffic.
THICKNESS DESIGN OF PLAIN CEMENT CONCRETE PAVEMENTS ON SOILS SENSITIVE TO DIFFERENTIAL SETTLEMENTS
Authors: Vos Erik
Published: January 2025

As large parts of the Netherlands are situated on a soft subsoil, a new thickness design method has been developed in which differential settlements can be taken into account in a quantitative sense. Supposing a sinusoidal settlement profile of the subgrade, the bending stresses in concrete slabs have been calculated. These proved to be dependent on the quotient of settlement amplitude and the square of the half wave-length as well as on the slab dimension, slab stiffness and the modulus of subgrade reaction. To determine the fatigue life these stresses have been combined with those of the traffic loading and those following from a thermal gradient. For a practical case of a highway pavement a nomograph has been derived, relating the thickness of the slabs to the settlement amplitude and the half wave-length, Also critical values for the settlement characteristics have been calculated in order to avoid that the slabs would loose contact with the subgrade. From the calculations it followed that for concrete pavements differential settlements with half wave-lengths which are sometimes the slab's length are acceptable. However, settlements which take place over small distances (about one time the slab's length) must be avoided for they could lead very soon to premature cracking.