Additions of Minerals in Clays of Morelia Region, Mexico: Effects on Volumetric Stabilization and Color

2012 ◽  
Vol 1374 ◽  
pp. 215-224
Author(s):  
W. Martínez Molina ◽  
J. L. Ruvalcaba Sil ◽  
E. M. Alonso Guzmán ◽  
A. Flores Rentería ◽  
M. Manrique Ortega ◽  
...  
Keyword(s):  
Portland Cement ◽  
Cultural Heritage ◽  
Mechanical Behavior ◽  
The Other ◽  
Type Ii ◽  
Cement Type ◽  
Lime Stabilization ◽  
Heritage Constructions ◽  
Colorimetric Measurements ◽  
The Aesthetic

ABSTRACTClays were used intensively in cultural heritage’s monuments and objects. Conservation procedures can be performed specifically for earthen materials using stabilized clays, considering that the aesthetic features must be preserved in order to avoid drastic differences and the lost of their patrimonial value.This work presents the study of the mechanical behavior of clay stabilized with different materials following the norm ASTM D 6276 – 99a, for lime stabilization. The effects of other stabilizers on the clay were studied as well. For these purposes, lime, gypsum, Portland cement (type II), sodium hydroxide, and dehydrated cactus fibers of white cactus opuntia in concentrations of 2, 4, 6, 8 and 10 wt% were added to a clay from Morelia region.Atterberg limits were determined to calculate the linear and volumetric stabilization. The best volumetric stabilization values were chosen to prepare samples to measure the mechanical behavior under compression, tension and flexion strengths. Colorimetric measurements were also performed on the stabilized clays to determine the best preparation with the most suitable aesthetic qualities to perform conservation treatments on monuments and cultural heritage constructions made with earthen materials.The highest values for compression were observed for gypsum and mucilage additions while the highest tension was obtained for mucilage ones. Gypsum addition had the bigger rupture module under flexion. On the other hand, the color of the stabilized clay is closer to the original clay color for cement, lime and mucilage preparations.

scholarly journals Impact of maturation conditions for concrete on its compressive strength

2020 ◽  
Vol 19 (2) ◽  
pp. 101-110
Author(s):  
Joanna Witkowska-Dobrev ◽  
Olga Szlachetka ◽  
Paulina Spiek
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
The Other ◽  
Atmospheric Conditions ◽  
Cement Type ◽  
Strength Tests ◽  
Curing Method

This paper aims to present the results of compressive strength tests of concrete specimens, prepared according to two recipes, after 2, 7 and 28 days of maturing in four different environments. The concrete specimens had the same w/c ratio, the same amount of aggregate of particular fractions, the addition of a superplasticizer, but they differed in the cement type. In one recipe, the Portland cement CEM I 32.5R was used, in the other – pozzolanic ash cement CEM IV/B(V) 32.5R-LH/NA. Concrete specimens with dimensions of 100 x 100 x 100 mm made according to both recipes were placed in individual ripening environments: in cuvettes with water, soaked and wrapped with construction foil, left in room conditions in the laboratory, placed outside the laboratory and being exposed to the atmospheric conditions. The obtained compressive strength results confirmed that the best way of curing concrete is the wet cure (in cuvettes with water). It has been proven that the choice of proper curing method is key in terms of compressive strength.

scholarly journals PAINÉIS CIMENTO-MADEIRA DE Eucalyptus saligna COM DIFERENTES ADITIVOS QUÍMICOS E MÉTODOS DE FORMAÇÃO

FLORESTA ◽  
2014 ◽  
Vol 45 (2) ◽  
pp. 349 ◽  
Author(s):  
Vinicius Gomes Castro ◽  
Rafael Leite Braz ◽  
Rafael Rosa Azambuja ◽  
Pedro Lício Loiola ◽  
Setsuo Iwakiri ◽  
...  
Keyword(s):  
Portland Cement ◽  
Physical And Mechanical Properties ◽  
Dry Weight ◽  
Cement Composites ◽  
Type Ii ◽  
Cement Type ◽  
Chemical Additives ◽  
Eucalyptus Saligna ◽  
Cold Press ◽  
Wood Cement Composites

Este trabalho teve como objetivo avaliar o potencial de uso de diferentes aditivos químicos e métodos de formação na produção de compósitos cimento-madeira com clone de Eucalyptus saligna. Utilizou-se o cimento Portland tipo CP II-Z, como aglutinante mineral, e cloreto de cálcio (CaCl2) e cloreto de magnésio (MgCl2),como aceleradores de cura do cimento. Os painéis cimento-madeira foram produzidos pelo método de prensagem na prensa de pratos de 50,5 x 38,5 x1,5 cm, e pelo método de adensamento por vibrocompactação em dimensões de 35 x 7 x1,5 cm. Os painéis foram formados com densidade nominal de 1 g/cm³ e relação cimento:madeira de 2,75:1. Com base nos resultados, pode-se concluir que: (I) os testes de hidratação mostraram que a madeira é compatível com o cimento Portland tipo II; (II) o uso de cloreto de cálcio e de magnésio na proporção de 3% em relação à massa do cimento proporcionou incremento nas propriedades físicas e mecânicas dos painéis produzidos pelos dois métodos de formação avaliados; (III) os painéis produzidos pelo método de adensamento por vibrocompactação apresentaram menor densidade média, maior estabilidade dimensional e melhor tração perpendicular do que os painéis produzidos pelo método tradicional de prensa de pratos.Palavras-chave: Compósito cimento-madeira; vibro compactação; aceleradores de cura. AbstractWood-cement boards of Eucalyptus saligna with different chemical additives and methods of formation. The aim of this work was evaluate the potential use of different chemical additives and methods of formation for wood-cement composites with Eucalyptus saligna clones. Portland cement type II-Z was used as mineral bonding and Calcium chloride (CaCl2) and Magnesium chloride (MgCl2) as accelerator of the cement hydration. The wood-cement panels were produced by the cold press method with dimensions of 50.5 x 38.5 x1.5 cm, and by vibro-compaction densification with 35 x 7 x 1.5 cm. Both methods used a nominal density of 1.0 g/cm3 and wood: cement ratio of 1:2.75. Main results: (I) Hydration tests showed that E. saligna wood is compatible with Portland cement type II; (II) Use of Calcium and magnesium chlorides at 3% in relation of the cement dry weight improve physical and mechanical properties of wood-cement composites produced by studied methods; (III) Composites produced by vibro-compaction densification presented lower density, higher dimensional stability and higher internal bond than composites produced by the traditional cold press method.Keywords: Cement-wood composites; vibro-compaction; chemical accelerators.

scholarly journals Research on Planning and Design of Urban Architectural Color in Changchun

2020 ◽  
Vol 165 ◽  
pp. 04029
Author(s):  
Zhang Cui
Keyword(s):  
Creative Thinking ◽  
Building Materials ◽  
Design Guidelines ◽  
The Other ◽  
New Era ◽  
Color Design ◽  
Planning And Design ◽  
Surrounding Environment ◽  
The Aesthetic

Architecture is the soul of city color. The planning focus of city color is city architecture, especially the planning control of the main wall color of street buildings. The design of architectural color should not only consider the surrounding environment of the building, the content of the building and the building materials, but also proceed from the aesthetic needs and conform to the principle of color engineering. On this basis, the plan proposes color design guidelines and relies on scientific and standardized “urban building color design guidelines” to achieve the purpose of maintaining the original appearance of history and creating a new era style. Besides the traditional buildings, the other “architectural color guidelines” should leave more room for manoeuvre and not restrict the creative thinking of architects.

scholarly journals Progenitors and Hydrodynamics of Type II and lb Supernovae

1996 ◽  
Vol 145 ◽  
pp. 137-147
Author(s):  
S. E. Woosley ◽  
T. A. Weaver ◽  
R. G. Eastman
Keyword(s):  
Black Holes ◽  
Light Curve ◽  
Mass Loss ◽  
Massive Stars ◽  
The Other ◽  
Shock Interaction ◽  
Type Ii ◽  
Residual Hydrogen ◽  
Ordinary Type ◽  
The One

We review critical physics affecting the observational characteristics of those supernovae that occur in massive stars. Particular emphasis is given to 1) how mass loss, either to a binary companion or by a radiatively driven wind, affects the type and light curve of the supernova, and 2) the interaction of the outgoing supernova shock with regions of increasing pr3 in the stellar mantle. One conclusion is that Type II-L supernovae may occur in mass exchanging binaries very similar to the one that produced SN 1993J, but with slightly larger initial separations and residual hydrogen envelopes (∼1 Mʘ and radius ∼ several AU). The shock interaction, on the other hand, has important implications for the formation of black holes in explosions that are, near peak light, observationally indistinguishable from ordinary Type II-p and lb supernovae.

Adorno’s Philistine: the Dialectic of Art and its Other

2019 ◽  
pp. 1-31
Author(s):  
Paul Ingram
Keyword(s):  
The Other ◽  
Critical Potential ◽  
The Social ◽  
The Aesthetic ◽  
Critical Turn ◽  
The Ideal

Abstract Theodor Adorno’s philistine functions as the other of art, or as the ideal embodiment of everything that the bourgeois aesthetic subject is not. He insists on the truth-content of the derogation, while recognising its unjust social foundation, and seeking to reflect that tension in a self-critical turn. His model of advanced art is negatively delimited by the philistinism of art with a cause and the philistinism of art for enjoyment, which represent the poles of the aesthetic and the social. The philistine is also the counterpart to the connoisseur, with the interplay between them pointing to his preferred approach to aesthetics, in which an affinity for art and alienness to it are combined without compromise. However, Adorno fails to realise fully the critical potential of the philistine as the immanent negation of art and aesthetics.

An FTIR, SEM and EDS investigation of solidification/ stabilization of chromium using portland cement Type V and Type IP

1992 ◽  
Vol 30 (3) ◽  
pp. 273-283 ◽  
Author(s):  
M.Yousuf A. Mollah ◽  
Yung-Nien Tsai ◽  
Thomas R. Hess ◽  
David L. Cocke
Keyword(s):  
Portland Cement ◽  
Cement Type ◽  
Type V

Burn-in procedures for a generalized model

2001 ◽  
Vol 38 (02) ◽  
pp. 542-553 ◽  
Author(s):  
Ji Hwan Cha
Keyword(s):  
The Other ◽  
Replacement Policy ◽  
Type I ◽  
Type Ii ◽  
Failure Model ◽  
Minimal Repair ◽  
Optimal Replacement ◽  
Complete Repair ◽  
Optimal Replacement Policy ◽  
Type Of Failure

In this paper two burn-in procedures for a general failure model are considered. There are two types of failure in the general failure model. One is Type I failure (minor failure) which can be removed by a minimal repair or a complete repair and the other is Type II failure (catastrophic failure) which can be removed only by a complete repair. During a burn-in process, with burn-in Procedure I, the failed component is repaired completely regardless of the type of failure, whereas, with burn-in Procedure II, only minimal repair is done for the Type I failure and a complete repair is performed for the Type II failure. In field use, the component is replaced by a new burned-in component at the ‘field use age’ T or at the time of the first Type II failure, whichever occurs first. Under the model, the problems of determining optimal burn-in time and optimal replacement policy are considered. The two burn-in procedures are compared in cases when both the procedures are applicable.

Marguerite Yourcenar, traductrice

Babel ◽  
1994 ◽  
Vol 40 (1) ◽  
pp. 21-37
Author(s):  
Ivo R.V. Hoefkens
Keyword(s):  
The Other ◽  
Political Sphere ◽  
Negro Spirituals ◽  
Marguerite Yourcenar ◽  
Other Hand ◽  
The Aesthetic ◽  
Literary Output ◽  
Ethical Communication ◽  
The Waves ◽  
Second Period

Marguerite Yourcenar, known as an author, is also the translator of about a dozen works. My purpose here is to trace the evolution of her oeuvre in the field of translation in relation to her literary output. I have divided the former into three distinct periods, the first of which covers the closing years of the 1930s, when Marguerite Yourcenar translated Virginia Woolf's The Waves and Henry James's What Maisie Knew. Her interest in these authors is to a large extent stylistic. On the other hand, the translation of Constantin Cavafy's poetry, which was begun during the same period, reflects the intimist themes to be found in Marguerite Yourcenar's early narratives {Alexis and the others), although she was then already seeking out other thematic sources. The translation was only published in 1958. It consequently falls within a second period: that of the "présentations critiques" (critical commentaries). These major efforts in translation {Présentation critique de Constantin Cavafy, La Couronne et la Lyre, Fleuve profonde, Sombre rivière) are marked by a manifest preoccupation with the aesthetic. But themes of a more universal character and engagement in the socio-political sphere also enter into the choice of the texts for translation (negro spirituals, Présentation critique d'Hortense Flexner). These translations were contemporaneous with the creation of Marguerite Yourcenar's most important novels, namely Mémoires d'Hadrien and L'OEuvre au Noir. The last of the three periods, the 1980s, finds her tackling far less ambitious projects, the function of which tends increasingly towards ethical communication. The only one of them that bears any resemblance to the "présentations critiques" is the essay on Yukio Mishima and the translation of Cinq Nô Modernes, assuming that these are to be considered as an ensemble. Here, as elsewhere, it also emerges that Marguerite Yourcenar is largely indifferent to the existence of other translations.

The Feasibility of Using Micro Silica Sand Powder as Partial Replacement of Cement in Production of Roller Compacted Concrete

2021 ◽  
Vol 1021 ◽  
pp. 21-34
Author(s):  
Zahraa Alaa M.A. Ali Khan ◽  
Zena K. Abbas
Keyword(s):  
Portland Cement ◽  
Minimum Cost ◽  
The Other ◽  
Silica Sand ◽  
Engineering Properties ◽  
Crushed Stone ◽  
Partial Replacement ◽  
Roller Compacted Concrete ◽  
Water Curing ◽  
Micro Silica

Roller compacted concrete (RCC) is a special type of concrete with zero or even negative slump consistency. In this work, it had aimed to produce an RCC mix suitable for roads paving with minimum cost and better engineering properties so, different RCC mixes had prepared i.e. (M1, M2, M3, and M4) using specified percentages of micro natural silica sand powder (SSP) as partial replacement of (0%, 5%, 10%, and 20%) by weight of sulfate resistant Portland cement. Additionally, M-sand, crushed stone, filler, and water had been used. The results had obtained after 28 days of water curing. The control mix (M1) had satisfied the required f ‘c with accepted results for the other tests. M2 mix with SSP of 5% had achieved the highest results. The f ’c for sawed cubes of (10*10*10) cm had increased by 2.26% and 3.16% when tested in directions (ꓕ and //) to the direction of loading respectively. R results for sawed prisms of (38*10*10) cm had increased by 8.78% and 8.43% when tested on top and bottom faces respectively. The density had increased by 1.04% while the absorption and volume of permeable voids had decreased by 8.11% and 7.83% respectively. The UPV results had also increased by 2.44% and 0.81% for cubes and prisms respectively when compared to the control mix. M3 mix with SSP of 10% had also achieved satisfactory results when compared to the control mix.

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