The aim of this thesis is design and programming of a numerical model of shrinkage of cement composites using physical discretization and solved by parallel processing. Introduction is about the shrinkage of cement composites and explanation of terms, which are included in this thesis. The main part deals with programming of the output model, the procedure of its creation and the results of simulations.

The target of this dissertation is based on the specified shape of plastic part to develop search technology of plastic injection molds, to the technological design process and construction of injection molds, including the necessary calculations. The project includes a search and a practical sections. Based on information from a search section a suitable material was chosen, which became the basis for practical section. The practical section with basic technology calculation is complemented by filling simulation analysis and stress analysis of critical elements. A part of this dissertation is the set of the drawings.

This thesis is focused on the principles of behavior of shrinkage reducing agents (SRA) in alkali-activated materials based on blast furnace slag. The main focus of this work is selecting the most suitable admixture based on experiments, by which will be achieved through minimal shrinkage and will have negative effect on the properties of alkali-activated blast furnace slag at the same time. In experimental section of this work, the surface tension as individual additives as their mixtures with pore solution were measured primarily. Then the testing samples composed of blast furnace slag, water glass and addition of SRA were prepared. Of these samples was measured shrinkage and weight loss. Moreover, their mechanical properties such as flexural and compressive strength were monitored. Next, the beginning and the end of solidification was studied using the Vicat device and last but not least workability. The hydration process of alkali-activated materials with SRA was measured calorimetrically. Finally the microstructure in prepared samples was observed using scanning electron microscopy (SEM-EDS) and the total porosity was determined by mercury porosimeter.

[pt] O presente trabalho tem como objetivo investigar o efeito da adição de fibras dispersas de polipropileno e de curauá na fluência básica a compressão e na retração autógena e por secagem de pastas de cimento nas primeiras idades. O comprimento das fibras de polipropileno e de curauá foi de 12 mm e a fração volumétrica variou de 0,03 a 0,30 por cento da massa do cimento. As pastas de cimento tinham relação água/cimento de 0,44. A retração autógena foi estudada pelo método do tubo corrugado, acompanhando a variação do comprimento desde as primeiras horas. A avaliação da retração por secagem livre se deu por meio da medição da variação de comprimento de primas durante os primeiros dias de idade. Utilizou-se o método do teste do anel para observação do comportamento das pastas sob retração restrita no intuito de se obter a idade de fissuração de cada pasta. A abertura dessas fissuras também foi acompanhada com auxílio de um microscópio. Testes de fluência a compressão foram realizados para determinar a deformação por fluência em idade jovem. Foi observada uma redução significativa da retração autógena nas pastas reforçadas com 0,30 por cento fibras de curauá. A adição de ambas as fibras reduziu ligeiramente a retração por secagem livre, não tendo diferença significativa entre os teores de fibras. Também foi observado atraso no desenvolvimento de fissuras e redução na abertura de fissuras para ambas as fibras independente do teor. As pastas com adição de fibras exibiram, no geral, uma ligeira melhora na deformação por fluência. / [en] The present research aims to investigate the effect of the addition of discrete polypropylene and curauá fibers on the early age autogenous and drying shrinkage and basic creep in compression in cement pastes. The length of the polypropylene and curauá fibers was 12 mm and the volume fraction varied from 0.03 to 0.30 percent of the mass content of cement. The cement pastes had water to cement ratio (w/c) of 0.44. Autogenous shrinkage tests were carried out following the Corrugated Tube Method, monitoring the length changes since casting. The evaluation of free drying shrinkage was given by measuring the length changes during the first days of age. The ring test method was used to determine the age when cracking occurred. The crack opening of the samples was also monitored by a microscope. Compressive creep tests were performed with cylindrical specimens to determine the early age creep strain. A significant reduction of the autogenous shrinkage was observed in the specimens with 0.30 perent of curauá fibers. The addition of both fibers slightly reduced the free drying shrinkage of the specimens and the fiber content did not appear to influence significantly the shrinkage behavior of the specimens. A delay in the development of cracks and a reduction in crack opening for specimens with both fibers were also observed. This behavior was similar for all fiber content. Pastes reinforced with fibers exhibited, overall, a slight improvement in creep strain. The addition of 0.30 percent of polypropylene fibers showed greater improvement in creep strain.

I höga hus, i storleksordningen 100 m och högre, med vertikalbärande stomme av stål och betong kan differentialsättningar uppstå då de olika materialen deformeras olika. Detta ger med tiden lutande bjälklag. I det här arbetet har ett beräkningsprogram tagits fram med hjälp av Mathcad för att räkna ut de slutliga deformationerna och hur mycket man behöver kompensera för skillnaderna i deformation genom att gjuta bjälklagen med fall. Programmet är tänkt att användas av WSP i projekteringen av höga hus. Med hjälp av programmet har parametriska studier gjorts och det visade sig att genom att ändra på vissa parametrar kan differentialsättningarna utjämnas. I vissa fall kan detta medföra att gjutning med fall ej är nödvändigt. / When high buildings are built with steel and concrete collaborating, some problems may occur because the materials deform differently. The differences in the final deformations make horizontally casted floors start to lean over time. In this study a program has been developed in Mathcad to calculate the final deformations and differences. The differences can then be compensated by casting the floor with a slope. The program is supposed to be used by WSP to project high buildings. The program has been used for some parametric studies to show how different parameters can decrease the differences. If this makes the differences small enough it will not even be necessary to cast floors with a slope.

All form of activity in a building is in need for a sound platform to be able to operate. The performance of concrete floor in industrial spaces is of importance because there are greater demands on industrial concrete floor.  By making sure that the necessary recommendation regarding casting an industrial concrete floor is followed, the risk for failure is reduced. The Swedish Concrete Association (2008) recommends a w/c ratio of approximately 0.55 for industrial floors. This would result in a concrete strength class of C30/37 with an abrasive resistance adequate for most industrial floors. From an economical perspective an approach for concrete rehabilitation is the bonded overlay, which has been used for many years and has the intension to extend the life of structural concrete slabs. For concrete overlay having a matching material to the substrate is the main recommendation, in addition in a fully bonded overlay to the substrate there is less risk for cracking and edge lifting. From a mechanical perspective a crack develops when the stresses in concrete exceeds the tensile strength. Shrinkage and creep of concrete in both overlays and industrial floors are important factors that contribute in development of cracks which have considerable effect on failure of the structure; therefore it is useful to find an accurate prediction model to predict shrinkage and creep. The literature study that has been carried out in this thesis is mainly about shrinkage, creep, industrial floor, overlays and tensile stress prediction. In addition the following calculation models for prediction of creep and shrinkage of concrete have been reviewed in this paper: Eurocode 2, fib Model Code 2010, ACI 209R-92, Swedish code BBK04 and Swedish concrete manual Material. In order to study the differences between the mentioned models two example cases for calculation of shrinkage and creep in industrial floor and  bonded overlay with the mentioned methods have been carried out, also the tensile stress development in bonded overlay has been calculated according to a method proposed by Prof. Silfwerbrand (1997). Since it was not possible to consider all types of concrete and conditions which will affect the outcome, only one type of concrete C30/37 with w/c ratio of 0.55 for industrial floor and w/c ratio of 0.40 for overlay is taken as an example in this thesis. Some of these methods take only a few factors into consideration; however the others are more detailed and treat numerous factors. The simple methods such as BBK04 or the graph in Eurocode 2 for calculating the creep coefficient can be used in the lack of existence of sufficient input parameters to be able to roughly estimate the final value. The predicted shrinkage did differ by using different models, however the final value of the creep coefficient was quiet similar regardless of the used model. There are some important parameters such as ambient relative humidity, age at loading, duration of drying and duration of loading which should be included in predicting models since these parameters affect shrinkage and creep considerably. Also aggregate type has an important role in both creep and shrinkage; however aggregate type (modulus of elasticity of aggregate) was not included in any of the studied models. Choosing a factor according to the type of aggregate might be helpful for better prediction.

I Sverige produceras varje år grovt uppskattat ca. 1,5–2,0 miljoner m2 industrigolv av betong [1]. Resultaten är varierande och det vanligaste felet hos dessa golv är sprickor [2]. I sprickorna letar sig vatten och i vissa fall klorider ned och förorsakar armeringskorrosion. Armeringen expanderar pga. korrosionen och spränger sönder betongen. Golvet blir inte längre estetiskt tilltalande samtidigt som livslängden förkortas avsevärt och golvytan blir ojämn vilket försvårar eventuell trucktrafik. Sprickor uppkommer främst pga. tvångskrafter som uppstår när betongen krymper. Storleken på sprickorna avgörs av betongens benägenhet att krympa, armerings-innehåll och graden av tvång. DynaMate som bygger och underhåller Scanias serviceverkstäder och industrilokaler upplever stora problem med sprickbildning hos industrigolven. Sprickorna medför stora kostnader i form av driftstopp, rivning, reparation och eventuell nyproduktion [3]. Föreliggande rapport baseras framförallt på litteraturstudier utifrån en rad rapporter, artiklar och handböcker men även normer. Intervjuer har genomförts med sakkunniga personer för att ta del av deras erfarenheter och åsikter. För att även få bättre insikt i utförandeskedet har författarna närvarat vid två olika gjutningar av industrigolv. För att minska sprickrisken i betonggolv, orsakad av betongens fria krympning, krävs en betongsammansättning som minimerar den fria krympningen, ett armeringsinnehåll som överstiger minimiarmering, fogar som tillåter rörelser i plattan och en långsam uttorkning. Det har upplevts att problem med sprickor i betonggolv beror på okunskap, olika viljor och slarv bland involverade aktörer. Därför är det även viktigt med tydliga mål och bra kommunikation mellan alla aktörer. På uppdrag av DynaMate har ett förslag till åtgärdsprogram för minskad sprick-bildning tagits fram. Detta kan ligga till grund för framtida golvprojekt och på sikt minska de stora kostnader som underhåll och reparationer medför. / Roughly estimated 1,5–2,0 million m2 of industrial concrete floors are produced in Sweden every year [1]. The results vary and the most common matter/failure among these floors is cracks [2]. Water finds its way down in the cracks and in some cases chlorides, which causes corrosion of the reinforcement. The reinforcement expands due to the corrosion and makes the concrete burst. The floor is no longer esthetically appealing. At the same time the lifetime is shortened substantially and the floor surface becomes uneven which complicates any truck traffic. Cracks arise due to restraint forces that develop because of concrete shrinkage. The width of the cracks is determined by the concretes tendency to shrink, reinforcement content and the extent of restraint forces. DynaMate builds and maintains Scania service centers and industrial facilities. They are experiencing major problems with cracking in industrial floors. The cracks bring large costs in terms of downtime, demolition, repair and any new production. The present report is based mainly on literature research from reports, articles and handbooks but also norms. Interviews were performed with qualified persons to share their experiences and opinions. To receive even more knowledge the authors attended two different castings of industrial floors. A reduction of cracking in concrete floors caused by the free shrinkage requires a concrete composition which minimizes the free shrinkage, reinforcement content in excess of minimum reinforcement, a slow drying and joints that allow movements. It was believed that the problem with cracks in concrete floors is due to ignorance, different wills and carelessness among the involved actors. Consequently it is also important to have clear objectives and good communication between all actors. On behalf of DynaMate a proposal for actions to reduce cracking was prepared. That proposal can form the basis for future flooring projects and ultimately reduce the significant costs due to maintenance and repairs.

La presente investigación buscara la dosificación optima de microfibra para controlar la retracción plástica comparando microfibras sintéticas de polipropileno FIBRA ULTRAFINA de la marca CHEMA y microfibra sintética acrílica DRYMIX RC4020 de la marca SUDAMERICANA DE FIBRAS, considerando las dosificaciones que recomiendan los proveedores por cada metro cubico de concreto. Se realizarán ensayos de laboratorio en 17 mezclas para luego medir la retracción plástica en cada una de ellas utilizando los paneles normados por el ASTM C1579-13, midiendo también las demás propiedades que serán comparadas con el desempeño de un concreto convencional. El resultado de esta investigación será el valor de dosificación óptima con la que se logre disminuir la retracción plástica sin afectar otras propiedades del concreto, tales como resistencia a la compresión, tracción, flexión y trabajabilidad. De igual manera se realizará un análisis económico de acuerdo con las dosificaciones realizadas de las fibras anteriormente mencionadas. / The present investigation will search the optimal dosage from microfiber to control the plastic shrinkage comparing the polypropylene synthetic microfiber Fibra Ultrafina by the brand CHEMA and the acrylic synthetic microfiber Drymix RC4020 by the brand SUDAMERICANA DE FIBRAS, considering the dosages per cubic meter that the providers recommend. It will perform laboratory tests in 17 mixes by then measure the plastic shrinkage in each of them using the standardized panels by the ASTM C1579-13, also will measure the other properties that will be compared with the performance from a conventional concrete. The investigation result will be the optimal dosage valor that can reduce the plastic shrinkage without affecting the other concrete properties like the compressive strength, tensile strength, flexural strength and slump. Likewise, it will perform an economic analysis according the fiber dosages aforementioned. / Tesis

El concreto es uno de los materiales más utilizados en el mundo de la construcción, de las cuales cada material en la mezcla depende de la resistencia que se requiera de acuerdo al análisis estructural. Dentro del proceso de producción de concreto debemos garantizar que el cemento reaccione químicamente y desarrolle la resistencia para la cual fue diseñada, para esto es importante mantenerlo hidratado en ese tiempo mediante el proceso de curado. Una técnica aún no tan conocida es el auto-curado del concreto, por lo cual es una necesidad saber cuál es su influencia en el desarrollo de la resistencia y en la disminución del porcentaje de agrietamiento del concreto en estado plástico. El objetivo de esta tesis es determinar la influencia que tiene el reemplazar un cierto porcentaje de ladrillo triturado como reemplazo del agregado grueso; evaluando la resistencia a la compresión, resistencia a la flexión, y el agrietamiento por contracción plástica del concreto. Se desarrolló con 3 diferentes porcentajes de reemplazo de ladrillo triturado que son: 15%, 21%, 27% del peso del agregado grueso para la resistencia a la compresión (f’c) de 280 kg/cm2. Se concluyó que reemplazo del agregado grueso por ladrillo triturado es efectivo cuando es usado hasta un máximo de 21%. Los resultados obtenidos son óptimos y viables en el tiempo, mostrándonos un aumento en la resistencia a la compresión, resistencia a la flexión y la disminución del porcentaje de fisuras en estado plástico. / Concrete is one of the most used materials in the world of construction, of which each material in the mixture depends on the strength required according to the structural analysis. Within the concrete production process, we must ensure that the cement reacts chemically and develops the resistance for which it was designed, for this it is important to keep it hydrated at that time through the curing process. A technique not yet so well known is the self-curing of concrete, so it is a necessity to know what its influence is in the development of resistance and in the reduction of the percentage of cracking of concrete in the plastic state. The objective of this thesis is to determine the influence of replacing a certain percentage of crushed brick as a replacement for coarse aggregate; evaluating the compressive strength, flexural strength, and cracking by plastic shrinkage of concrete. It was developed with 3 different percentages of crushed brick replacement that are: 15%, 21%, 27% of the weight of the coarse aggregate for the compressive strength (f’c) of 280 kg / cm2. It was concluded that replacement of coarse aggregate with crushed brick is effective when used up to a maximum of 21%. The results obtained are optimal and viable over time, showing an increase in compressive strength, flexural strength and a decrease in the percentage of cracks in the plastic state. / Tesis

A process in which low methoxyl pectin is applied to the surface of meat carcasses and poultry to reduce shrinkage, maintain color and improve shelf life was evaluated. A 3.0 percent aqueous low methoxyl pectin (acidified with 1.4 percent acetic acid if required) was applied to beef, lamb and turkey carcasses by spraying and caused to form a gel coating by overspraying with a 3.5 percent calcium chloride salt solution. Turkey carcasses treated with acidified pectin or acidified pectin after 3.0 percent acetic acid dip for 30 seconds were not significantly improved in shelf life over carcasses which were acid dipped 30 seconds. Pectin coating of turkey carcasses was determined infeasible due to discoloration. Pectin coated lamb carcasses were significantly lower in shrinkage (0.71 ±0.04 percent) (p Pectin coated beef carcasses were significantly lower in shrinkage (0.44 ±0.38 percent) (p Both acidified pectin (pH 3.5) and unacidified pectin (pH 4.1) significantly (p