Atualmente o maior impacto ambiental do concreto como material de construção origina-se das emissões de CO2 durante a produção do cimento. Uma das alternativas atualmente utilizadas para minimizar este impacto, é a utilização de adições minerais como substituição ao cimento. Entre as diferentes adições utilizadas, o uso de fíler calcário parece ser uma alternativa interessante para melhorar a sustentabilidade do uso do concreto na construção. Consequentemente, o presente estudo foca a análise do impacto da substituição do cimento por fílers de origem calcária (dolomita) no comportamento do concreto em estado fresco e endurecido, especialmente focando-se numa avaliação reológica e na retração por secagem do material. Para tal fim, foram formulados três microconcretos com teores de fíler calcário de 80%, 60% e 20% em relação ao peso dos finos totais (cimento mais fíler calcário). O teor de finos totais e de água foram mantidos constantes para todas as formulações resultando em misturas com similar volume de pasta. O comportamento reológico das misturas foi avaliado num reômetro de movimento planetário. Foram moldados corpos de prova para caracterização mecânica e acompanhamento da retração por secagem. A porosidade das pastas também foi avaliada usando a porosimetria por intrusão de mercúrio. As propriedades reológicas como a tensão de escoamento e a viscosidade foram influenciadas pelo teor de substituição de cimento por fílers. Maiores volumes de fílers na pasta produziram menores tensões de escoamento e, por consequência, maiores valores de abatimento foram obtidos. No entanto, a viscosidade plástica aumentou com teor de fílers. No estado endurecido, a maior substituição de cimento por fílers diminui a intensidade da retração por secagem devido ao menor teor de cimento na pasta e a modificações na estrutura porosa do material. Os resultados experimentais da retração foram comparados com os valores obtidos pelos modelos de previsão da retração: ACI 209, CEB-FIP, B3 e GL2000. Observou-se que os modelos superestimam os valores da retração conforme aumenta a substituição de cimento por fílers na pasta. Portanto, esses modelos devem ser calibrados considerando outros fatores, tais como: a quantidade de fíler utilizado em substituição de cimento. Esta consideração poderia otimizar o uso dos modelos em fase de projeto para verificar se os valores da retração esperados estão dentro dos limites normalmente aceitos. / Currently the biggest environmental impact of concrete as a building material originates in CO2 emissions during the production of cement. For this reason, one of the alternatives currently used to reduce these emissions is the use of mineral additions as cement replacement. Among the different additions used, the use of limestone fillers to replace cement appears to be an interesting alternative for improve the sustainability of the concrete used in construction. Consequently, this study focuses on the analysis of the impact of the replacement of cement by limestone fillers in fresh and hardened concrete, especially focusing on rheological behavior and shrinkage of the material. To this end, three microconcretos were formulated with fillers limestone content of 80%, 60% and 20% by weight relative to the total fine (limestone fillers and cement). The total content of fine and water were held constant for all formulations resulted in mixtures with similar volume of paste. The rheological behavior of the mixes was evaluated in a planetary motion rheometer. For mechanical characterization and measurement of shrinkage, specimens were molded. The porosity of the pastes was also evaluated using mercury intrusion porosimetry. The rheological properties such as yield stress and viscosity were influenced by the amount of cement that was replaced by fillers. Further filers volumes in the pulp produced smaller flow stress and, consequently, higher allowance values were obtained. Larger volumes of filler in the paste produced lower yield stresses and, consequently, higher slump values were obtained. However, the plastic viscosity increased with filers content. In the hardened condition, the largest cement replacement by limestone fillers reduced the intensity of shrinkage due to the lower content of cement paste and changes in the porous structure of the material. The experimental results of shrinkage were compared with the values obtained by shrinkage prediction models: ACI 209, CEB-FIP, B3 and GL2000. It was observed that the models overestimate the shrinkage values with increasing cement replacement by limestone fillers. Therefore, these models must be calibrated considering other factors such as the amount of fillers used as cement replacement This consideration would optimize the use of these models in the design phase to verify that the values of the expected shrinkage are within the limits normally accepted.

People have varied and complex relationships with stone, in its raw geology and in its altered forms. Often, however, in cultural contexts, stone remains in the background, as a taken for granted and unremarkable element of the material world. In this thesis, stone moves into the foreground. The research presented here explores how close attention to those who work intimately with stone can disclose unexpected and absorbing stories. The cultural geologies extracted and presented in this thesis cast light on the diversity of ways in which people relate to, and with, the land; and experiment with a range of different ways in which these relations can be narrated. Set on the Jurassic Coast, in the south west of England, the stone exposures that emerge along the margin between land and sea offer a productive site for developing a cultural geological approach. The limestones, shales and clays are framed, in this work, by the narratives of quarrymen and geologists. The work explores how their particular knowledges are formed, and how they exist within wider historical and ecological understandings. Their narratives bring the stratigraphy to life, and draw attention to the hidden worlds within it. The different priorities and perspectives of quarrymen and geologists are shown to lead in different directions, interweave, or run parallel. The very specific languages and descriptions they employ reveal a level of complexity and richness of detail that is mirrored in the stone. Using an approach that combines close observation and creative practice, this study examines stone at a variety of scales, and in different contexts. The work engages with specific stone types, landscapes, voids, buildings and objects. Processes of working stone through practices of lettering, sculpture and masonry elicit understandings of the material that reach far beneath its surface. The absent spaces of quarries are then explored, showing how voids can be animated with knowledge, and how destructive processes can generate creative potential, when sensitively worked and considered. Lastly, the study draws all these ideas together in a discussion of stone assemblages in buildings, to see how voices from geology and quarrying can foster greater understanding of how buildings were constructed in the past, and how we conserve them into the future.

Natural hydraulic lime and natural cement have been used in the building industry for centuries. These inorganic hydraulic binders are called "traditional" or "alternative" because they can, in some cases, substitute modern Portland cement. The recent increased interest in these binders is due not only to their use in restoration practices, but also because their production and use is less energetically demanding than in modern cements. Historically, many types of hydraulic binders were produced in the regions of Bohemia and Moravia. However, much information has been lost about their manufacturing process, which raw materials were used, and we are uncertain of the exact character and properties of the burned material. To date, studies have only addressed the impact of the chemical composition of raw material on the parameters of the burned material - all this is well known for Portland cement, much less for other types of hydraulic binders. The aim of this dissertation was to study the various types of raw materials (limestone containing non- carbon admixtures) and to understand the characteristics of their respective hydraulic lime and natural cement. This was done by analyzing the impact of conditions (highest achieved burning temperature and time of burning) and the mineral and chemical...

A pavement construction designed to cope with the different type of traffic loads; it is exposed to and at the same time it can resist the effect of the climate. A road structure consists of sub- and superstructure which is divided by a boundary known as terrace. During the construction of unbound layers (base course and sub-base course) in the superstructure, it is always ensured that the material meet the requirements for bearing capacity and the degree of compaction. These parameters are controlled by various laboratory tests and control methods. To obtain increased knowledge of the material and improve the quality of the compaction in the field, it is necessary to perform laboratory tests in order to determine material properties. A base course material 0/ 32 mm limestone from Gotland (Hejdeby) was investigated in this study. To determine properties of the material various laboratory tests such as proctor compaction test, Micro-Deval, Los Angeles, and grain distribution curve are conducted. To investigate how grain size distribution affects technical properties of the material, the 0/32 mm material was modified with two different samples; grain size distribution of 2/32 mm excluding superior material content, and 0+/32 mm with enhanced superior material content. The purpose of this study was to examine changes in material behavior during proctor compaction. Two aspects of changes in material behavior were emphasized in this study; the optimal water content and maximum dry density, as well as changes of both. As a reference for the limestone features, a traditional 0/32 mm tonalite material (granite) from Vällstaverket was used relating to proctor investigation. Material's resistance to abrasion and fragmentation was investigated by two methods: Micro-Deval and Los Angeles. The results were compared with other rock materials. Furthermore the bearing capacity of the material was verified by examination of the Young's modulus and degree of compaction, as well as properties of water content and dry density, at three trial areas on Gotland. This is performed with various methods such as static plate loading test, light weight deflectometer, density gauge/SDG200, and water/sand volume meter measurement test. By comparing results from different methods of measurement, it may indicate a relationship between these. Test area 3 consists of two smaller test areas which have different water content. The bearing capacity (Young's modulus) and the degree of compaction were measured after each roller passage. Different relationships were obtained between the amount of roller overpass, with Young's modulus of material; as well as degree of compaction. It was found in this study that limestone from Gotland (Hejdeby) maintain its position as construction material for the unbound layers of the road. The result from static plate load which indicated high E V2 values (Young's modulus) was obtained from the field, and it suggests that a fine bearing capacity can be achieved in the use of limestone.

The construction industry is closely tied to economic development economies, and increasing demand also presents a significant contribution to environmental degradation. The construction industry’s impact to climate change is led by the 8% contribution from the production of concrete mixtures, more specifically, the production of cement. The combination of using advanced mixdesign techniques (e.g., particle packing models -PPM) and more sustainable ingredients poses as a promising alternative to overcome concrete environmental impact. However, there is a lack of studies regarding the fresh state difficulties arising from the aforementioned combination. Therefore, this work appraises the use of mobility parameters to overcome the fresh state issue raised when mix-designing mortar mixtures through PPM and with high volume of limestone filler. Twelve mixtures were developed with distinct cement content ranging from 150 kg/m3 to 320 kg/m3. To produce sustainable mortar, besides using PPM, cement content was replaced by limestone filler. Time dependent fresh state analysis was performed using mortar slump flow and a rheological profile. In the hardened states, the compressive strength, porosity, surface electrical resistivity tests were performed. The main findings of the project observed a strong correlation between mobility parameters and five distinct rheological parameters: flow behaviour parameter, high shear rate viscosity and shear stress, low shear rate viscosity and shear stress. Additionally, in the hardened state, a dilution parameter IPScement was used to appraise the dilution and filler effect of the mortar mixtures. The works highlighted a promising method to produce eco-efficient mortars.

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Throughout Central Florida surface water and ground water are decreasing in quantity and quality in part because of excess Nitrate and Phosphorus nutrients. Stormwater runoff serves as a medium for transport of Nitrate and Phosphorus to surface water and ground water. The goal of this experiment is assess the Nitrate and Phosphorus removal in stormwater using select media. The results of a literature search, batch test experimentation and column test experimentation are used to determine an optimal media blend that may be implemented in detention ponds to reduce Nitrate and Phosphorus. The extensive literature search revealed 32 different media that may be used to remove Nitrate and Phosphorus. Each potential media was qualitatively and quantitatively evaluated based on 5 criteria: 1) relevance, 2) permeability, 3) cost, 4) availability in Florida, and 5) additional environmental benefit. The top 7 performing media: Florida peat, sandy loam, woodchips, crushed oyster shell; crushed limestone, tire crumb and sawdust were selected for batch test experimentation. The aerobic conditions in batch test experimentation prohibited the growth of denitrifying bacteria, therefore media mixes were selected for column test experimentation based on Ammonia and Orthophosphate concentrations. Batch test experimentation showed the most effective media to be 50% sand, 30% tire crumb, 20% sawdust by weight (media mix 1) and 50% sand, 25% sawdust, 15% tire crumb, 10% limestone by weight (media mix 2). Media mix 1, media mix 2 and a control are tested in column test experimentation, where the control is site soil from Hunters Trace development in Ocala, Florida. Column test experimentation models a dry detention pond where water passes through a 48 inch unsaturated zone then a 48 inch saturated zone. To test Nitrate and Orthophosphate removal potential, pond water augmented with Nitrate (0.38, 1.26, 2.5 mg/L NO3-N) and Orthophosphate (0.125, 0.361, 0.785 mg/L PO4-P) was pumped into the columns. Media mix 1 and media mix 2 outperformed the control in both Nitrate and Orthophosphate removal. Media mix 1 and media mix 2 had Nitrate removal efficiencies ranging from 60% to 99% and the control had Nitrate removal efficiencies ranging from 38%-80%. Media mix 1 and media mix 2 averaged Orthophosphate removal efficiencies ranging from approximately 42% to 67%. For every run in every influent Orthophosphate concentration the saturated control added Orthophosphate to the water. The Nitrate and Orthophosphate removal performances for media mix 1 and media mix 2 could not be directly compared because of different influent saturated nutrient concentrations.

In recent years the nutrient levels of the Upper Floridan aquifer have been increasing (USGS, 2008). An example of this is found in Ocala, Florida where Silver Springs nitrate concentrations have risen from 0.5 mg/L in the 1960 s to approximately 1.0 mg/L in 2003 (Phelps, 2004). Because stormwater is a contributor to surficial and groundwater aquifer recharge, there is an increasing need for methods that decrease nitrogen and phosphorus levels. A laboratory column study was conducted to simulate a retention pond with saturated soil conditions. The objectives of the column studies reported in this thesis were to investigate the capabilities of a natural soil and soil augmentations to remove nitrogen and phosphorus for a range of concentrations at three different temperatures. An analytical attempt to model the columns through low order reaction kinetics and derive the corresponding temperature conversion constant to relate the rate constants is also presented. The Media Mixes were selected through a process of research, preliminary batch testing and then implemented in column studies. Three columns measuring three feet in length and 6 inches outer diameter were packed with a control and two media mixes. Media Mix 1 consisted of 50% fine sand, 30% tire crumb, 20% sawdust by weight and Media Mix 2 consisted of 50% fine sand, 25% sawdust, 15% tire crumb, 10% limestone by weight. The control column was packed with natural soil from Hunter s Trace retention pond located in Ocala, Florida. The reaction rates for nitrate are best modeled as first order for Media Mix 1, and zero order for the Control and Media Mix 2. The reaction rates for orthophosphate are best modeled as zero order, second order and first order for the Control, Media Mix 1, and Media Mix 2 respectively. The best overall media for both nitrate and orthophosphate removal from this study would be Media Mix 1. Media Mix 2 does have the highest average orthophosphate removal of all the mixes for all of the temperatures; however Media Mix 1 outperforms Mix 2 for the other two temperatures. The best column for Nitrate removal is the Media Mix 1 column. The temperature conversion factors for nitrate were found to be 1.11, 1.1, and 1.01 for Media Mix 1, the Control and Media Mix 2 respectively. The temperature conversion factors for orthophosphate were found to be 1.02, 0.99, and 0.95. As well as temperature conversion factors, the activation energies and frequency factors for the Arrhenius Equation were investigated. Average values corresponding to each column, species, and temperature would be inaccurate due to the large variation in calculated values.

Limestone is one of the main components of cement production. Limestone has been quarried in Skövde, Sweden, since the end of 19th century and Cementa AB has been operating the quarry since 1973. Aside from limestone, there are also Alum shale of Cambrian age, mudstones as well as bentonite layers of Ordovician age present in the quarry.  The production of cement evidently is important for Sweden’s infrastructure, and the quarry in Skövde is one of few known locations in the country with limestone with the right composition. Therefore, it is important to increase the knowledge regarding the character of the limestone to make accurate predictions for the future regarding the cement production. The geological knowledge of the area is already extensive; however, the aim of this thesis is to expand this knowledge further by constructing a 3D geological model. The data which has been used to construct the model are field observations, drill core data, chemical data, high-resolution pictures (photogrammetry) and resistivity measurements (field and samples). The resistivity measurements were done using the multiple gradient array, and apparent resistivity was inverted using Res2Dinv. The geological modelling was done using Leapfrog geo (© Seequent Systems, Incorporated). Two models have been proposed as a result of this project; one where high-grade limestone of lesser quality and whitestone has been regrouped with two other units (A) and one including all units (B). In the most recent drilling campaign, the nomenclature used to distinguish the units has been modified and does not differentiate high-grade limestone of lesser quality and whitestone from the rest. This affects coherence of the model and for this reason two models have been built. Both models show roughly flat lying units in the area of interest. Both low-grade limestone and lower waste stone units have consistent thickness in both models. The major difference between the models is how the high-grade limestone unit is modelled as a consequence of the additional units in model B. The result from the resistivity measurements shows unexpectedly low values, when compared to values from the literature as well as the measurements on hand samples from the quarry. The reason for these low values is still unclear, and therefore resistivity data has been used with caution. Considering this, it appears that resistivity measurements is not a suitable technique to characterize the subsurface in this particular area.  The models produced in this project provides information regarding thickness and extent of the units and overlying soil. As such, the new knowledge can be used to plan future prospecting campaigns, make projections, and estimates within current mining permits and evaluate how future mining can be conducted. / Kalksten är huvudkomponenten när det kommer till cementproduktion, vilken också behöver ha en specifik kemi för att vara lämplig att tillverka cement av. Kalksten av denna specifika kvalité har brutits i Skövde, Sverige, sedan slutet av 1800-talet. Cementproduktionen startade dock 1924 och Cementa köpte upp gruvan och fabriken 1973. I brottet finns förutom kalksten även alunskiffer, slamsten och bentonitlager. Vidare finns det två olika kvalitéer på kalkstenen, en med högt kalciumoxidvärde och en med lägre kalciumoxidvärde. Totalt representerar de formationer som finns i gruvan en 50 miljoner år lång historia av sedimentation. Cement utgör en grundläggande del för Sveriges infrastruktur, och brottet i Skövde är en av få platser i landet med en kalksten som har rätt kemi. Därmed är det viktigt att utöka kunskapen gällande karaktären på kalkstenslagren i och vid brottet för att kunna göra mer korrekta uppskattningar om Sveriges framtida cementproduktion. I dagsläget är kunskapen om geologin i och kring gruvan omfattande tack vare bland annat tidigare prospekteringskampanjer. Syftet med detta arbete är utöka den geologiska kunskapen ytterligare genom att konstruera en geologisk 3D modell. Denna geologiska 3D modell har skapats av data såsom borrhålsdata, resistivitetsmätningar samt drönarbilder för att bättre karakterisera de olika geologiska formationerna. På grund av att indelningen av de geologiska enheterna har varit olika mellan de tidigare prospekteringskampanjerna har två 3D modeller med olika upplösning skapats i stället för en. Modelleringen har fokuserats på ett område nordväst om nuvarande brytområde. Båda modellerna har sub-horisontella geologiska enheter inom intresseområdet. Vidare har modellerna liknande tjocklek och utbredning på enheterna i sin övre del, men skiljer sig åt längre ner. Detta på grund av att den ena modeller har flera enheter, vilket således även påverkar närliggande enheter. Dessa två modeller har utökat den geologiska kunskapen om området, till exempel de geologiska enheternas mäktighet och utbredning, samt hur mäktigt jordtäcket i området är. Denna nya kunskap kan användas för att planera och estimera hur brytning kan ske i framtiden. Det är dock viktigt att poängtera att det är modeller som skapats, vilka är antaganden av verkligheten.

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