The aim of this paper is to summarize and evaluate properties of polymers modified modified mortar, their durability and the possibility of surface treatment. Recently, the requirements for additional surface treatment of architectonal concrete are increased and the application of polymer-modified mortar can accelerate and simplify the realization of visible concrete. Polymer-modified mortar with the addition of powder photocatalysts can significantly reduce and thus increase the availability of photoactive concrete structures. The experimental part deals with the addition of photocatalyst to the polymer-modified mortar and the subsequent assessment of the photocatalytic properties, the possibility of modification cement mortars with anorganic pigments and the application of transparent coatings for the enhancement of color saturation and resistance.

The diploma thesis is concerned with study of preparation and properties of historic mortars. In theoretical part, there is summarized the historic progress of mortars and their material composition. The experimental part is focused on proposition of mortar mixes. The diploma thesis referring to actual research on Institute of Technology of Building Materials and Components, FCE VUT in Brno. The base mixe of historical mortar came from this research. In experiment, there is the base mixe of historical mortar modified with gypsum. In the first phase of the experimental part the basic technological and aplication properties are assessed. The second phase of the experimental part is focused on the course of hydration of the binder in different environments and subseqeunt determination of the phase composition by X-ray diffraction analysis. The aim of the thesis is to determine the optimal amount of gypsum and to optimize the recipe of historical mortar.

Mortar is the cementitious binding material placed between masonry blocks to create a composite system. The American Society of Testing and Materials (ASTM), along with other organizations, have established the testing of prismatic mortar specimens for evaluating mechanical properties, like compressive strength. Mortar joints, however, possess vastly different characteristics compared to prismatic specimens, especially in terms of geometry and water content. These differences prevent a direct comparison of compressive strength between prismatic specimens and actual mortar joints in the assembly. The objective of this study was to analyze Type S mortar joints, with particular emphasis on specimen shape and water content, to draw accurate comparisons of compressive strength to ASTM prescribed mortar prismatic specimens.To examine the effect of water on mortar compressive strength, three different water contents were evaluated across nearly all testing series. Cubic (2-in) and cylindrical (2 by 4-in) mortar specimens were prepared and tested according to ASTM guidelines to verify the compressive strength relationship described by ASTM and to be used as comparative data. In addition, a small masonry wall was assembled and cured in a laboratory to simulate true properties of mortar joints. Mortar joints subjected to testing were a combination of thin slices cut from prismatic specimens as well as in-place bed joints cured between concrete masonry units (CMU). Two unorthodox test methods, the double punch test (DPT) and helix pull-out test (HPT), were selected as methods for assessing mortar joints. In addition, confining effects from neighboring material common to DPT were evaluated as a function of specimen face dimensions. The compressive strength ratio obtained through testing of 2-in cubic and 2 by 4-in cylindrical specimens was lower than ASTM recommendations. This may have been in part due to testing cylindrical specimens with rough surfaces and no capping material. DPT confinement on 2-in square and 2-in diameter circular specimens was found to be equivalent. Thinly sliced specimens tested in DPT showed increases in compressive strength as water content and specimen thickness decreased. As a whole, DPT results on thin mortar slices showed promise for accurate comparison to prismatic mortar specimens. In-place mortar joints tested in HPT showed moderate to high scatter. In addition, evaluation via HPT was determined to be more appropriate for qualitative rather than quantitative assessments of in-situ mortar.

Purpose - The purpose of this study is to extend the understanding of the business model of video game retailers using online and physical stores focusing on the impact of digital platforms on the retailing industry within the context of video game industry considering different actor’s perspectives like retailers and consumers. Design/methodology/approach - This is a multiple-case study based on deductive reasoning. In this qualitative study, two cases of click-and-mortar retailers operating in the Swedish video game industry have been considered along with feedback from customers. Online personal interviews and semi-structured interviews have been conducted with retailers and customers respectively. Both primary and secondary data have been used to conduct the study. Findings - Findings show that video game retailers need to encourage engagement through incentives and other activities in order to create value and change up their formats and sales strategies through pricing to reach new customers and focus on design of their online store fronts to convey trustworthiness.  Research limitations - A major limitation has been the COVID-19 pandemic spreading during the writing of this paper, which resulted in companies backing out to refocus their efforts. Another limitation has been the legal aspect as companies owned by bigger publishers denied to take part in the study to avoid revealing sensitive information. Practical implications - It offers some insightful practical suggestions to retailers who are struggling hard to adopt digital transformations in the industry. Originality - Authors’ proposed research model, based on Sorescu et al. (2011)’s retail business model and the empirical findings, contribute in the less explored domain of research on business models from retailer’s perspectives. Moreover, it adds values in industry specific study like the video game industry in Sweden considering all actors, which is argued as scarce.

Concrete in Sweden has traditionally been manufactured with natural aggregate from glaciofluvial eskers. There is a need to preserve the remaining eskers because of their cultural value and importance for water filtration, thus natural aggregate has to be replaced. The most realistic alternative is to use crushed rocks. The major problem with crushed rocks in concrete production is the workability. This is because crushed rocks have less favorable properties. The fragments are flakier and have a rougher surface than natural aggregates that have been rounded in water. Without any amelioration of the crushed rock, to reach a certain workability and strength, the amount of cement in the mix has to be increased. Cement production requires large amounts of energy and the decarbonation of limestone releases large amounts of CO2. Combined, the release of CO2, due to burning and decarbonation of limestone, accounts for about 5% of the global CO2 emissions. An increase in cement consumptions is less desirable. Thus to replace natural aggregates, the use of crushed rocks has to be optimized as regard cement consumption. Several crushed aggregates, most from granitic rocks, from all over Sweden were analysed in this study. These crushed rocks were characterized according to their grading, specific surface, shape and petrography and compared to natural sand. Rheological tests that reveals the workability in detail was performed on mortars. The tests showed that as regard workability the 0-2 mm fraction is the most important factor. Further, the maximum aggregate size was gradually increased up to 16 mm, to have a more realistic approach to the concrete produced by the building industry. The results showed that with grading optimization and superplasticizer, some crushed rocks can be used for concrete production without increasing, and even decreasing, the cement consumption. This research also contemplated the use of filler. As a mineral admixture it can improve the compressive strength. It can also be used to replace cement; a replacement up to 20 kg/m3 of cement by filler can be done without significant effect on compressive strength.

Behovet av en mer mobil granatkastare har resulterat i en utredning av möjliga koncept som sedan ska gallras bort och resultera i en investering i ett nytt fordonsmonterat granatkastarsystem. Denna rapport beskriver utredningen av en potentiell risk med ett av de potentiella koncepten. Konceptet består av att placera en granatkastare i personalutrymmet i en stridsfordon90-vagn och avfyra den med öppna takluckor. Detta koncept har använts av andra länder och deras arméer, bland dem finns USA som använder sig av fordonsplattformen Stryker. Säkerheten för soldaterna i Försvarsmakten är högt prioriterat och strängt reglerat av standarder och reglementen som ständigt revideras. Den största potentiella risken med det aktuella konceptet har identifierats att vara ljudtrycksnivån som soldaterna utsätts för vid avfyrning. Om en undersökning av ljudtrycksnivåerna skulle visa att konceptet inte är säkert så finns därmed inget behov att vidare utreda konceptet och det skulle därmed bli uteslutet. För att fastställa vilka nivåer som kan förväntas av denna lösning så planerades och genomfördes en testskjutning med hjälp av FMV Test och Evaluering i Karlsborg samt representanter från BAE Systems Hägglunds. Provskjutningen genomfördes genom att placera den svenska 120mm granatkastaren M/41 i ett testchassi, som i stora drag motsvarar Strf90 chassiet, och sedan skjuta granater i flera olika testscenarion för att undersöka parametrarna elevation, laddning, riktning, användning av tratt, vinkel på takluckor öppen/stängd bakre lucka samt upphöjt chassi.Provet visade att dubbla hörselskydd kommer att behövas inne i fordonet och att potentiellt kommer personal längst in i fordonet att klara sig med enkla hörselskydd. Högst troligt är att det slutgiltiga konceptet kommer att ha en begränsning på 30-50 avfyrningar per dag med högsta laddning, 40-50 med laddning 7 och 70-80 med laddning 5. Användning av en tratt visade sig effektivt och minskade ljudtrycksnivån med 5-10 dB och därmed ökar antalet tillåtna avfyrningar till över 100 skott per dag för högsta laddningen. / The need of a more mobile mortar has led to an investigation of possible concepts which will be narrowed down and end in a purchase of a self-propelled mortar system. This report describes the exploration of a possible risk with one of these concepts. The concept is to place a mortar in the back storage area of a CV90 where it will be fired with open hatches. This concept has been used by other countries armies, amongst them the US Army which uses the Stryker vehicle platform.The safety of the personnel in the Swedish Army is prioritized and strictly regulated by set standards and regulations which are frequently revised. The largest potential risk with the concept in question has been identified to be the sound pressure acting on the personnel. If the concept would indicate levels over the permissible levels it would not have any potential and would not be further investigated.To conclude which levels a concept like this would have, a test shooting was planned and conducted with the help from FMV Test and Evaluation centre in Karlsborg and representatives from BAE Systems HägglundsThe shooting was conducted by placing the Swedish 120 mm mortar GRK M/41 inside a CV90 chassis mock-up and firing grenades in several scenarios which would test the different parameters; elevation, charge, direction, BAD, angle of roof hatches, open/closed rear door and elevated chassis.The test showed that double ear protectors will be needed in the vehicle and with the potential that it will suffice with single ear protectors for personnel furthest in the vehicle. It is most likely that it will be restrictions on number of permissible rounds fired per day of 30-50 firings for charge 9, 40-50 with charge 7 and 70-80 with charge 5.The use of BAD resulted in the sound level decreasing between 5-12 dB which would increase the restrictions to a maximum of 100 rounds per day for maximum charge.

The doctoral thesis deals with the reactivity of burnt clays in connection with modified lime mortars. The theoretical part of the doctoral thesis provides an overview of the properties of lime mortars, their quality and ways of their degradation. The different types of burnt clays (brick powder, bentonites and burnt clay shale), their origin, properties and factors affecting their reactivity and methods of its evaluation are stated. The properties and reactivity of burnt clays are evaluated on the basis of determination of pozzolanic activity, mineralogical and chemical composition, surface area, density, content of the amorphous phase and granulometry in the experimental part of the doctoral thesis. The compositions of lime mortars containing burnt clays and evaluation of an impact of burnt clay on the properties of mortars in the fresh and hardened state are given. Consistency, bulk density, workability and air content of mortars in the fresh state are evaluated. Strength characteristics depending on the time, water absorbability, porosity, capillary attraction, adhesion, coefficient of diffusion resistance, frost resistance, shrinkage, mineralogical composition and microstructure of mortars in the hardened state are evaluated. Attention is also paid to the influence of the cellulose ether addition into the modified lime mortars.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21062号 / 工博第4426号 / 新制||工||1688(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 河野 広隆, 准教授 服部 篤史, 准教授 山本 貴士 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

yes / Test results of thirty six ground granulated blast-furnace slag (GGBS)-based mortars and eighteen fly ash (FA)-based mortars activated by sodium silicate and/or sodium hydroxide powders are presented. The main variables investigated were the mixing ratio of sodium oxide (Na2O) of the activators to source materials, water-to-binder ratio, and fine aggregate-to-binder ratio. Test results showed that GGBS based alkali-activated (AA) mortars exhibited much higher compressive strength but slightly less flow than FA based AA mortars for the same mixing condition. Feed-forward neural networks and simplified equations developed from nonlinear multiple regression analysis were proposed to evaluate the initial flow and 28-day compressive strength of AA mortars. The training and testing of neural networks, and calibration of the simplified equations were achieved using a comprehensive database of 82 test results of mortars activated by sodium silicate and sodium hydroxide powders. Compressive strength development of GGBS-based alkali-activated mortars was also estimated using the formula specified in ACI 209 calibrated against the collected database. Predictions obtained from the trained neural network or developed simplified equations were in good agreement with test results, though early strength of GGBS-based alkali-activated mortars was slightly overestimated by the proposed simplified equations.

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