Impact of Different Curing Methods and Drying Conditions on Drying Shrinkage Induced Curling

Prolonged wet curing is thought by many to provide only improvements in concrete performance. Also, because of the large surface to volume ratio of volume change sensitive structures such as slabs on grade, differential moisture loss can cause unwanted deflections, reduction in ride quality, and cracking. This work has shown that there is a potential increase in the amount of curling of these structures that are wet cured and then subject to 1-D drying in severe drying conditions. Experiments on paste beams with different water-to-cementitious ratios and cured for different durations with wet and sealed curing methods as well as alternative tests on concrete beams with different curing lengths suggested that the extended wet curing causes a pore structure refinement resulting in greater saturation and consequently greater shrinkage. A simplified 1-D, drying diffusion and shrinkage model was able to adequately predict experimentally measured peak curling deflections as well as the entire curling history after further adjustments to input parameters and confirmed the effect of saturation on curling. Also, the ability of this analytical model to capture the mechanistic sources of wet curing on peak deflections was evaluated by comparing its predictions to those acquired via a fully nonlinear diffusion model. It was shown the overall deflection predictions by the approximate linearized model were in greater agreement with the measured data than with the full, nonlinear solution.Curing compounds are used to retain moisture which promotes hydration to develop a tight microstructure. This work provided a quantitative comparison between different curing compounds, wet, sealed, and no curing not made in previous studies and showed that adequate amounts of curing compounds are a useful curing method for members sensitive to differential drying such as concrete pavements in severe drying conditions. However, it was shown in less severe drying conditions that the curling strains caused by drying were minimal since the drying rate was less significant. So, if the concrete pavements are to be used in a moist environment, the type of curing that is used on pavements will have very little impact on their curling deformations.Civil Engineerin

Reducing Curling from Drying Shrinkage of Concrete Pavements Through the Use of Different Curing Techniques

Reducing the deformation in concrete pavements through the use of curing at early ages was the main concern of this study. In this project, supported by the Oklahoma Department of Transportation (ODOT), results from the curling of the paste and concrete beams and the effects of curing techniques on them were discussed separately. Effectiveness of wet curing and how it changes the moisture gradient and surface properties, and also the efficiency of the curing compounds in reducing the moisture loss and curling deflections were investigated.Civil Engineerin

DEVELOPMENT AND IMPLEMENTATION OF A MECHANISTIC AND EMPIRICAL DESIGN GUIDE (MEPDG) FOR RIGID PAVEMENTS — PHASE 2

The work investigates the impact of curing methods and their impact on subsequent curling in both the laboratory and the field in different drying environments. Results are also presented for a field instrumentation of a CRCP pavement in Tulsa, Oklahoma that uses a number of different curing methods. Next, a sensitivity analysis is completed for typical Oklahoma jointed and continuously reinforced pavements with different base friction parameters. Then the results from Darwin-ME are compared with field performance of CRCP and JPC pavements in Oklahoma. Finally, the shrinkage and coefficient of thermal expansion of concrete pavement mixtures are investigated with different past contents.Final report, October 2012-October 2014N

New insights from reactivity testing of supplementary cementitious materials

Tests to determine the reactivity of supplementary cementitious materials (SCMs) by using isothermal calorimetry and thermogravimetric analysis have been proposed. In one such test, the heat release and calcium hydroxide consumption of SCMs mixed with calcium hydroxide (3:1 ratio of calcium hydroxide and SCM) at 50 °C in a 0.5 M potassium hydroxide environment are measured. In this study, we show the results of such testing for a large variety of SCMs and fillers, ranging from conventional materials such as fly ash, slag, silica fume, quartz, and limestone, to alternative materials such as calcined clays, municipal solid waste incineration fly ash, basic oxygen furnace slag, ground lightweight aggregates, ground pumice, ground glass pozzolan, and basalt fines. A total of 54 SCMs are tested using this approach. Results show that even among SCMs of the same type, there is considerable difference in the heat release and calcium hydroxide consumption, likely due to differences in amorphous content, chemical composition, and fineness, leading to different reactivities. Based on the response in the test, SCMs are classified into inert, pozzolanic, and latent hydraulic; the pozzolanic and latent hydraulic materials are further classified into less reactive and more reactive. The relationship between heat release and calcium hydroxide consumption depends on the chemical composition of the SCMs, and SCMs with high calcium, high alumina, and high silica contents show different relationships (determined by the slope of the heat release vs. calcium hydroxide plot)

DEVELOPMENT AND IMPLEMENTATION OF AN MEPDG FOR RIGID PAVEMENTS – PHASE 3 (FHWA-OK-16-04 2208)

The objective of the Phase III of this project is to validate and calibrate the MEPDG for the concrete pavement design in Oklahoma. Both jointed plain concrete pavement (JPCP) and continuously reinforced concrete pavement (JPCP) were considered. Seven LTPP segments and 50 PMS pavement segments, including 30 JPCPs and 20 CRCPs, were selected and used in the local validation/calibration analyses. The suitability of the national default design models in the MEPDG were assessed by comparing the measured field pavement performance recorded in the PMS and the predicted pavement performance by the MEPDG. It was found that the national default MEPDG under-predicted the transverse joint faulting for doweled JPCPs in Oklahoma. The faulting model has been calibrated based on the Oklahoma PMS data. The national default transverse cracking model seems to be adequate, but more data are needed to confirm this observation. There is also not enough information to evaluate the suitability of the CRCP punchout model due to the limited number of CRCPs in Oklahoma. Both the transverse cracking model and the punchout model need to be revisited when more pavement distress data become available. Finally, recommendations were made on using the MEPDG to design concrete pavements in Oklahoma.Final report, October 2011-December 2013N

Comparison of Moral Intelligence of Student’s Basic Sciences and Medical Internship in Tehran University of Medical Sciences in 2018

زمینه و هدف: هوش اخلاقی به عنوان اولین مؤلفه انطباق اخلاقی، پایه و اساس عمل اخلاقی است. دانشجویان پزشکی که در محیط‌های بالینی آموزش می‌بینند، علاوه بر شایستگی‌های فنی، بایستی از ارزش‌های اخلاقی مطلوب برخوردار باشند. این مطالعه با هدف مقایسه وضعیت هوش اخلاقی دانشجویان مقطع علوم پایه و کارورزی پزشکی دانشگاه علوم پزشکی تهران در سال 1397 انجام شده است. مواد و روش‌ها: این مطالعه مقطعی از نوع توصیفی ـ مقایسه‌ای بر روی 400 نفر از دانشجویان پزشکی در دو مقطع علوم پایه و کارورزی که به صورت تصادفی ساده انتخاب شده بودند و معیارهای ورود به مطالعه را داشتند، انجام شده است. برای جمع‌آوری داده‌ها از پرسشنامه 40 گویه‌ای هوش اخلاقی Keil و Lennick استفاده شد که دربرگیرنده چهار بعد و ده شاخص بود. برای تجزیه و تحلیل داده‌ها از نرم‌افزار SPSS 25 و آزمون‌های T-test، Chi-Square استفاده شد. یافته‌ها: میانگین نمره کل هوش اخلاقی در گروه کارورزی 78/7±13/72 و میانگین نمره کل هوش اخلاقی در گروه علوم پایه 28/8±11/72 بود. میانگین نمره کل هوش اخلاقی بیشتر کارورزان (7/62 درصد) و دانشجویان علوم پایه (7/60 درصد) در طبقه خوب به بالا بدست آمد. حدود 3/37 درصد از کارورزان و 3/39 درصد از علوم پایه دارای هوش اخلاقی ضعیف بودند. میانگین نمره کلی هوش اخلاقی در دانشجویان مقطع کارورزی نسبت به علوم پایه بالاتر بود، اما این اختلاف معنی‌دار نبود (026/0=P-Value). ملاحظات اخلاقی: این مقاله حاصل پایان‌نامه دکتری حرفه‌ای دانشگاه علوم پزشکی تهران است. در طول فرایند پژوهش سیاست‌های اخلاقی دانشگاه مطابق با اصول بیانیه هلسینکی، از جمله اخذ رضایت آگاهانه جهت شرکت در پژوهش رعایت شد. نتیجه‌گیری: شاخص‌های هوش اخلاقی در کارورزان نسبت به دانشجویان علوم پایه بیشتر نبوده است و این یافته‌ها نشانگر عدم موفقیت برنامه‌های آموزشی عمومی و اختصاصی در زمینه توسعه مهارت‌های اخلاقی در دانشجویان پزشکی است. بنابرین بازنگری کوریکولوم آموزش پزشکی با در نظرگرفتن مفاهیم اخلاقی پیشنهاد می‌شود.Background and Aim: Moral intelligence as the first component of moral compliance is the basis of moral action. Medical students trained in clinical settings, in addition to technical competencies, must have desirable moral values. The aim of this study was to compare the moral intelligence status of students of basic sciences and medical internships in Tehran University of Medical Sciences in 2018. Materials and Methods: This descriptive-comparative cross-sectional study was performed on 400 medical students in both basic sciences and internships who were randomly selected and met the inclusion criteria. A 40-item Moral Intelligence and Keil Lennick Questionnaire was used to collect data, which included four dimensions and ten indicators. SPSS 25 software and Chi-square t-test were used to analyze the data. Findings: The average total score of moral intelligence in the internship group was 72.13±7.78 and the mean total score of moral intelligence in the basic sciences group was 72.11±8.28.The average total score of moral intelligence of most interns (62.7%) and basic science students (60.7%) was obtained in a good category. About 37.3% of interns and 39.3% of basic sciences had poor moral intelligence. The mean total score of moral intelligence in internship students was higher than basic sciences, but this difference was not significant (P=0.026). Ethical Considerations: This article is the result of a professional doctoral dissertation at Tehran University of Medical Sciences. During the research process, the university's ethical policies were observed in accordance with the principles of the Helsinki Declaration, including obtaining informed consent to participate in the research. Conclusion: Indicators of moral intelligence in interns were not higher than students of basic sciences and these findings indicate the failure of general and specific educational programs in the field of developing moral skills in medical students. Therefore, it is recommended to revise the medical education curriculum by considering ethical concepts.   Cite this article as: Hajibabaee F, Yazdani Moghaddam M, Namazi HR, Yaseri M, Ashrafizadeh H, Shojaee AA. Comparison of Moral Intelligence of Student’s Basic Sciences and Medical Internship in Tehran University of Medical Sciences in 2018. Med Ethics J 2020; 14(45): e22