Micro-Deval Testing of Aggregates in the Southeast

Author(s):  
L. Allen Cooley ◽  
Robert S. James

Aggregate used in hot-mix asphalt (HMA) must be tough and durable, not only to withstand the effects of HMA production, transportation, and construction but also to resist the effects of traffic and the environment. Historically, the Los Angeles abrasion and impact test has determined the toughness of aggregates. The long-term durability characteristics of aggregates are generally determined using a soundness test: sodium or magnesium sulfate. During the National Cooperative Highway Research Program’s Project 4–19, the micro-Deval test, in conjunction with the magnesium sulfate soundness test, were recommended in lieu of the Los Angeles abrasion and impact test and other soundness tests. Therefore, a study was needed within the southeastern United States to evaluate the range in micro-Deval results that could be expected. This research characterized the toughness and durability of aggregates with respect to their micro-Deval test results. Seventy-two aggregate sources from eight different states were included in this research. These aggregates were rated as good, fair, or poor with respect to performance by the contributing state. On the basis of the results of this study, some large differences were found in micro-Deval test results within a given performance category. There was no relationship between Los Angeles abrasion and impact and micro-Deval test results.

2020 ◽  
Vol 1 (3) ◽  
pp. 97-111
Author(s):  
Soleen Jaber Ahmad Al-Hasan ◽  
R. Balamuralikrishnan ◽  
Motasem Altarawneh

Currently, various types of recyclable materials are used in civil engineering applications. One of the future challenges in the civil engineering field facing sustainability and the bulk utilization of waste materials without affecting the performance of the product related to the civil engineering field. Presence of bulk amounts of disposed and demolished materials including aggregates and undecomposed recycled polymers can be recycled. The main aim of reducing environmental impact and also reduction in the cost. Present research focusing on recycled polymers as partial replacement of bitumen in addition to recycled coarse aggregate in different percentages are investigated for its feasibility used in road construction. To achieve the objectives of the current research, 6 batches of bituminous samples were prepared and each case considered three samples for repeatability. The first batch is considered as a control sample without adding Recycled Coarse Aggregates (RCA) and recycled polymer. The second batch consists of 15% partial replacement of bitumen using polymer without recycled aggregate. Remaining batches 3 to 6 were 15% partial replacement of bitumen with polymer and partial replacement of coarse aggregates using recycled coarse aggregate say 25%, 50%, 75%, and 100%. Each batch was tested by reliable and standard tests in order to determine the most efficient mix (batch). The testing methods followed in this investigation are sieve analysis test, impact test, Los Angeles test, penetration test and marshal test. The results of sieve analysis test showed that the fineness modulus value for RCA equals to 4% with uniform graded graph. The specific gravity test results showed that RCA specific gravity is 2.61 which indicates that RCA is considered as coarse grained soils. Moreover, the Impact test for RCA equals 9.3%. In addition, the result for Los Angeles for RCA value is 19.07% and comparing it with the standard and it should be less than 30% is suitable for road construction. Furthermore, penetration test results of 15% partial replacement of bitumen using polymer showed that the average value equals 58 mm compared to 63.7 mm for bitumen without polymer. Finally, the result obtained from the Marshall Stability test showed that batch 5 partial replacement of bitumen 15% using polymer and the partially replaced normal coarse aggregate 75% with RCA gives better results in all aspects. A fruitful conclusion from this study is to follow the approach of utilization of recycled coarse aggregate along with recycled polymers in road construction. Doi: 10.28991/HEF-2020-01-03-01 Full Text: PDF


2004 ◽  
Author(s):  
K. S. W. H. Hendriks ◽  
F. J. M. Grosfeld ◽  
A. A. M. Wilde ◽  
J. van den Bout ◽  
I. M. van Langen ◽  
...  

2003 ◽  
Vol 1 (2) ◽  
pp. 198-207
Author(s):  
H. Mabel Preloran ◽  
Silvia Balzano

This paper explores the emotional world of a recent Mexican immigrant who lives in Los Angeles and is awaiting the results of the amniocentesis she has ambivalently agreed to. She is 45 years old and has given birth to two children with severe disabilities and two who are apparently normal. We focus our analysis on the woman's reactions and feelings during the nine days she spends waiting for the test results. We show that the standard prenatal genetic clinical protocol aimed at providing medical education and requiring professional neutrality and emotional detachment left the woman feeling rejected and subsequently unwilling to seek information or support from her clinicians. We find that while the intent of a protocol of neutrality is to enable patients to make informed decisions without feeling pressure from clinicians, some women want greater emotional engagement. We argue that professional neutrality can inhibit patient-clinician communication, hamper medical education, and ultimately detract from patients' ability to make informed medical choices. / El presente artículo explora el mundo emocional de Rocío, una inmigrante mexicana, quien se encuentra esperando los resultados de una amniocentesis que aceptó hacerse, a pesar de las dudas sobre la credibilidad y utilidad de la misma. Rocío, de 45 años, tenía ya otros hijos, dos con anormalidades severas y dos aparentemente sanos. Centramos nuestro análisis en los sentimientos y reacciones durante los nueve días que transcurren mientras espera el diagnóstico. En este trabajo mostramos cómo la forma de presentar la información médica puede llegar a entorpecer la toma de decisión de un paciente. El protocolo genético tiene por meta proveer información médica manteniendo una cierta distancia profesional y emocional. Estas condiciones hacen que, en nuestro estudio de caso, la paciente se sienta rechazada y sin deseos de acercarse al personal médico, ya sea en busca de apoyo emocional o información que aclararía sus dudas. Creemos que, mientras el objetivo de la neutralidad profesional es asegurar que el paciente decida con los conocimientos adecuados y, a la vez, sin sentirse presionado, algunas mujeres preferirían un mayor acercamiento emocional por parte del personal médico cuando deben decidir sobre pruebas o tratamientos. Creemos que la neutralidad profesional puede llegar a inhibir la comunicación médico-paciente, dificultar la comprensión de la información y, por último, obstaculizar la habilidad de tomar decisiones informadas por parte de los pacientes.


TAPPI Journal ◽  
2013 ◽  
Vol 12 (1) ◽  
pp. 45-50 ◽  
Author(s):  
LAURENCE SCHIMLECK ◽  
KIM LOVE-MYERS ◽  
JOE SANDERS ◽  
HEATH RAYBON ◽  
RICHARD DANIELS ◽  
...  

Many forest products companies in the southeastern United States store large volumes of roundwood under wet storage. Log quality depends on maintaining a high and constant wood moisture content; however, limited knowledge exists regarding moisture variation within individual logs, and within wet decks as a whole, making it impossible to recommend appropriate water application strategies. To better understand moisture variation within a wet deck, time domain reflectometry (TDR) was used to monitor the moisture variation of 30 southern pine logs over an 11-week period for a wet deck at the International Paper McBean woodyard. Three 125 mm long TDR probes were inserted into each log (before the deck was built) at 3, 4.5, and 7.5 m from the butt. The position of each log within the stack was also recorded. Mixed-effects analysis of variance (ANOVA) was used to examine moisture variation over the study period. Moisture content varied within the log, while position within the stack was generally not significant. The performance of the TDR probes was consistent throughout the study, indicating that they would be suitable for long term (e.g., 12 months) monitoring.


2019 ◽  
Vol Volume 2 Nomor 2 ◽  

There is a tendency in the education field today to return to the idea that children will learn better if the environment is created naturally. Learning will be more meaningful if children "experience" themselves what they are learning, not 'knowing' it. Target-oriented learning of material mastery proves to be successful in short-term 'remembering' competitions, but fails to equip children to solve problems in long-term life. The problems that would to be studied in this study are: (a) how is the improvement of Social Science learning outcomes by applying the Make A-Match Model to it? (b) how does the Make A-Match Model apply towards the learning motivation? The objectives of this study are: (a) want to know the improvement in Social Science learning achievement after the implemetation of the Make A-Match Model. (b) want to know the effect of Make A-Match Model towards students’ motivation of the subject after it is applied. This research is used two rounds of action research. In each round consists of four stages, namely: design, activity and observation, reflection and revision. The target of this research is the fourth grade students of Mongodow. The data obtained in the form of formative test results, observation sheets of teaching and learning activities. From the results of analysts obtained student achievement has increased from cycle I to cycle II namely, cycle I (65%), cycle II (83%). The conclusion of this research is the Make A-Match Model of Social Science learning could positively influence the motivation of learning of central students, and this learning model could be used as an alternative to Social Science learning.


1990 ◽  
Author(s):  
David M. Bailey ◽  
Stuart D. Foltz ◽  
Myer J. Rosenfield
Keyword(s):  

Author(s):  
Stephanie L. Shaver ◽  
Daniel S. Foy ◽  
Todd D. Carter

Abstract OBJECTIVE To describe signalment, clinical signs, serologic test results, treatment, and outcome of dogs with Coccidioides osteomyelitis (COM) and to compare those findings with findings for dogs with osteosarcoma (OSA). ANIMALS 14 dogs with COM and 16 dogs with OSA. PROCEDURES Data were retrospectively gathered from electronic medical records. RESULTS Dogs with COM were younger and weighed less than dogs with OSA. Six dogs with COM had appendicular lesions, 5 had axial lesions, and 3 had both appendicular and axial lesions; 9 had monostotic disease, and 5 had polyostotic disease. Axial lesions and nonadjacent polyostotic disease were more common in dogs with COM than in dogs with OSA, but radiographic appearance was not different between the 2 groups. Median IgG titer at diagnosis of COM was 1:48 and was significantly decreased after 6 and 12 months of treatment. Percentage of dogs with COM that had clinical signs was significantly decreased after 1, 3, 6, and 12 months of treatment. One year after initiation of treatment, 9 of 9 dogs were still receiving fluconazole and 8 of 9 dogs had positive results for serum IgG titer testing. CLINICAL RELEVANCE Dogs with COM typically had a rapid improvement in clinical signs after initiating treatment with fluconazole but required long-term antifungal treatment. Dogs with COM differed from dogs with OSA, but radiographic features had a great degree of overlap between groups, confounding the ability to make a diagnosis on the basis of diagnostic imaging alone.


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