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.

Growing pressure on the packaging design to enhance the environmental and logistics performance of a packaging system stresses the packaging designers to search new design strategies that not only fulfill logistics requirements in the supply chain, but also reduce the CO 2emissions during the packaging life cycle. This thesis focuses on the packaging design process and suggests some improvements by considering its logistics performance and CO 2emissions. A Green packaging development model was proposed for corrugated box design to explore the inter-dependencies that exist among compressive strength, waste and CO2emissions. The verification of the proposed model unveils the significance of a holistic view of the packaging system in the packaging design process and reveals the importance of packaging design decisions on the logistics performance and CO 2 emissions. The thesis finally concluded that the packaging logistics performance should be considered in a packaging design process to explore the Green packaging design solution.

<p> The central theme of the study is to identify strength-stiffness correlations for chemically treated subgrade soils in Indiana. This was done by conducting Unconfined Compression (UC) tests and resilient modulus tests for soils collected at three different sites, namely : US 31, SR 37 and I-65. At each site, soil samples were obtained from 11 locations at 30 ft spacing. The soils were treated in the laboratory with cement, using the same proportions used for construction, and cured for 7 and 28 days before testing. Results from the UC tests were compared with the resilient modulus results that were available. No direct correlation was found between resilient modulus and UCS parameters for the soils investigated in this study. A brief statistical analysis of the results was conducted, and a simple linear regression model involving the soil characteristics (plasticity index, optimum moisture content and maximum dry density) along with UCS and resilient modulus parameters was proposed.  </p>

Due to an increasing amount of aging tendencies in Swedish embankment dams, failures such as internal erosion has become a more common problem. Internal erosion is a phenomenon where certain soil material within the embankment dam is removed, often over a longer period of time. It is most common to occur at the inner core of the dam, and if it is allowed to continue for a longer time period the consequences can be disastrous. During the internal erosion, the inner material is washed out, creating larger voids and lowering the geotechnical stability of the dam. When larger voids start to appear, the seepage will increase allowing more material to be washed out and accelerating the process.  In order to repair an embankment dam, exposed to inner erosion, it requires both the location of the faults as well as a suitable method of repairing. A method to repair internal erosion is by using grout and injecting it into the location of the fault. The knowledge regarding what type of grout and how it should be treated is today lacking.  There are reasons to believe that a hardening mixture within an embankment dam using a till core will not cooperate well. For that reason, a grout with non-hardening properties is of interest. this thesis focuses on the Geomechanical strength parameters of two similar experimental non-hardening grouts. One with maximum grain size of 2 mm referred as grout 0/2, and one with maximum grain size of 4 mm, referred to as grout 0/4. The grouts consist of natural aggregates, calcium carbonate, water, bentonite, superplasticizer and defoamer.   The grouts are evaluated by its undrained shear strength, water content, bulk- and dry density using fall cone tests and uniaxial compressive strength tests. To evaluate the grouts angle of friction and angle of dilatancy together with young’s modulus, consolidated, drained triaxial tests were performed. Three tests with different consolidation pressures (50, 150 and 300 kPa) were performed for each grout. Since the grout will gain strength with time, the tests have been performed after certain number of days in order to see the development of the grouts. The laboratories stretch from 0 to 112 days since the time of mixing the grout, and was performed at Luleå University of technology.  Fall cone tests showed that the grout should most likely be mixed on site and left unstirred. Continuously stirring the grout quickly removed the grouts flowability which is why longer transportation should be avoided. At the same time, the accuracy of the grouts mixing is very demanding which needs to be taken into consideration.  Triaxial tests showed that the grout 0/2 had dilatant behavior for 50 and 150 kPa consolidation pressure while 300 kPa showed contractive behavior. The grout 0/4 had dilatant behavior for 50 kPa consolidation pressure while 150 and 300 kPa showed contractive behavior. A theory to explain this behavior was constructed where the bentonite is believed to be behind it. Bentonite slurries behave as a Bingham fluid, where it requires a certain amount of shear stress for the fluid to start to flow. With the same reasoning, the low consolidation pressures do not exceed that threshold, resulting in dilatant behavior. But once that threshold is surpassed the grout starts to contract. In addition, flow curve tests were performed for additives, superplasticizer and defoamer. Both these substances showed Newtonian behavior which leaves Bentonite to be the only additive with Binghamian behavior. / På grund av en ökad mängd med föråldrandetendenser hos svenska jordfyllningsdammar har brott så som inre erosion blivit ett alltmer vanligt problem. Inre erosion är ett fenomen där en viss jord inom jordfyllningsdammen är avlägsnad, generellt över en längre tidsperiod. Oftast inträffar detta vid den inre damkärnan och om erosionen är tillåten att fortskrida sig över en längre period kan konsekvenserna bli förödande. Inre erosion fungerar så att jordmaterial tvättas ut vilket skapar hålutrymmen och minskar den geotekniska hållfastheten för dammen. När större hålutrymmen bildats ökar läckaget som i sin tur tillåter mer material att bli urtvättat och processen blir accelererad. För att kunna reparera en jordfyllningsdam, utsatt för inre erosion, krävs både att platsen för brottet och metoden för att reparera är kända. En metod för att reparera inre erosion är genom att använda injektering och injektera hålutrymmet. Dock är kunskapen gällande vad för typ av injektering och hur den ska hanteras icke existerande i dagsläget. Det finns anledning att tro att ett härdande bruk inom en jordfyllningsdam, med en moränkärna, inte kommer samarbeta särskilt bra. På grund av det har ett bruk med icke-härdande egenskaper undersökt. Den här uppsatsen fokuserar på de geotekniska hållfasthetsegenskaperna för två liknande experimentella icke-härdande bruk. Ett med maximal kornstorlek på 2 mm benämnd som bruk 0/2 och ett med maximal kornstorlek på 4 mm, benämnd som bruk 0/4. Bruket består av natursand, kalciumkarbonat, vatten, bentonit, mjukgöringsmedel och skumdämpare. Bruken är utvärderade genom deras odränerade skjuvhållfasthet, vattenkvot, skrym- och torrdensiteten som har tagits fram från fallkorns-test och enaxiella trycktest (UCS).  För att utvärdera brukens friktionsvinkel och dilationsvinkel tillsammans med styvheten (initiella och 50 %) har konsoliderat, dränerat triaxiala tests utförts. Tre test med varierande konsolideringstryck (50, 150 och 300 kPa) har utförts för båda bruken. I och med att brukens hållfasthet kommer att öka med tiden, har testerna utförts efter ett visst antal dagar, för att se hur utvecklingen ser ut. Laborationerna har sträckt sig från 0 till 112 dagar sedan det att bruken har blandats, och utfördes vid Luleå Tekniska Universitet. Fallkornstesten visade att bruken bör med största sannolikhet blandas på arbetsplatsen och därefter förbli orörda. Kontinuerlig omrörning visade sig frånta brukens flytförmåga, vilket också är anledning till varför längre transporter bör undvikas. Samtidigt så är noggrannheten vid brukens blandning krävande vilket bör tas i beaktning. De triaxiala tester visade att bruk 0/2 visade ett dilatant beteende för både 50 och 150 kPa konsolideringstryck medan 300 kPa hade ett kontrakterande beteende. Bruket 0/4 hade dilatant beteende för 50 kPa konsolideringstryck medan 150 och 300 kPa visade kontrakterande beteende. En teori för att förklara detta beteende togs fram där bentoniten är den troliga orsaken. Bentonitblandningar (bentonite slurry) beter sig som en Bingham-vätska, där det krävs en viss mängd skjuvspänning för att få vätskan att börja flyta. Med samma resonemang applicerade på bruken innebar det att de låga konsolideringstrycken inte översteg tröskelvärdet, vilket resulterade i ett dilatant beteende. Däremot, när tröskelvärdet väl är överstiget börjar bruket att kontraktera istället. Det gjordes även flödestester på tillsatsmedlen, mjukgöringsmedel och skumdämpare. Testerna visade att båda medel betedde sig Newtoniskt, vilket lämnar bentoniten som det enda tillsatsmedlet med Bingham-beteende.

Introduction: Glass ionomers are available in sets of powder and liquid constituents, which are dispensed using a scoop and dropper bottle system prior to hand-mixing by an operator. Glass ionomers are also available in capsulated form, which is mixed in a suitable mechanical mixing machine prior to clinical use. Capsulation enables uniform proportioning of the powder and liquid. In this context, mixing time will be correct as an automated process is utilised, resulting in a cement mixture that is optimal and reproducible, with minimal air entrapment. Manufacturers promote the capsulated form as being time saving, and easy to dispense, with more accurate adaptation because of the use of an applicator to place the material. Aim: The aim of this in vitro study was to compare the performance of hand-mixed glass ionomer materials with their capsule-mixed equivalents in terms of compressive strength, surface hardness and porosity. Materials and Methods: Four groups of 10 cylindrical specimens were manufactured for each of the four specified hand-mixed posterior glass ionomers for each test that was performed: Riva Self Cure (RSCH) (SDI Limited); GC Fuji IX GP (FIXH) (GC Corp); Ketac Universal (KUH) (3M ESPE) and Ketac Molar Easymix (KMH) (3M ESPE). Similarly, four groups of 10 cylindrical specimens were manufactured for each of the four equivalent capsule-mixed posterior glass ionomers for each test that was performed: Riva Self Cure (RSCC) (SDI Limited); GC Fuji IX GP (FIXC) (GC Corp); Ketac Universal Aplicap (KUC) (3M ESPE) and Ketac Molar Aplicap (KMC) (3M ESPE). The compressive fracture strength of each specimen was determined after 24 hours using a universal testing apparatus. A compressive load of 1 mm/min was applied to the 6 mm long axis of each specimen. The load to fracture was recorded and the compressive fracture strength was calculated. Within one hour after compressive strength testing, a selection of fragments from each specimen was examined by Scanning Electron Microscope (SEM). Fragments were vacuum gold-sputter-coated prior to SEM examination. The fragments were observed at an operating voltage of 10kV, and over a range of magnifications to investigate crack propagation. The surface hardness of each specimen was measured with a digital micro-hardness tester with Vickers diamond indenter. The indenter was set at a load of 500mN at five predetermined regions of each specimen, with a dwell-time of five seconds. The five readings for each specimen were computed and the mean VHN in N/mm2 for each specimen was determined. Each specimen was observed and analysed for porosity using Micro-CT. Three-dimensional reconstructions were made of each specimen and the number of voids per volume (mm3) of specimen, the total volume of voids (mm3) per volume of specimen and the volume percentage of voids per volume of specimen were calculated. Results: RSCH and RSCC showed statistically significant differences when compressive strength (p=0.027), volume of voids (p=0.005) and volume percentage of voids (p=0.005) were compared. No statistically significant differences were found between RSCH and RSCC when surface hardness (p=0.124) and number of voids (p=0.221) were compared. When compressive strength (p=0.254) and number of voids (p=0.210) of FIXH and FIXC were compared, no statistically significant differences were found. Statistically significant differences were found when surface hardness (p=0.031), volume of voids (p<0.001) and volume percentage of voids (p<0.001) of FIXH and FIXH were compared. No statistically significant difference was found when compressive strength (p=0.090) of KUH and KUC were compared. Statistically significant differences were found when surface hardness (p<0.001), number of voids (p<0.001), volume of voids (p=0.004) and volume percentage of voids (p=0.004) of KUH and KUC were compared. Statistically significant differences were found between KMH and KMC when compressive strength (p<0.001), surface hardness (p=0.006), number of voids (p=0.001), volume of voids (p=0.010) and volume percentage of voids (p=0.010) were compared. Conclusion: The current study suggests that RSCC is more advantageous for clinical use compared to RSCH. The results as to whether the capsule-mix or the hand-mix product are superior for the examined properties for GC Fuji IX GP are inconclusive. KUC surpassed KUH in tests performed and is therefore recommended for clinical use. KMC out-performed KMH in all tests conducted, and is therefore advocated for use in clinical practice. / Dissertation (MSc)--University of Pretoria, 2019. / Community Dentistry / MSc / Unrestricted

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

The influence of tricalcium silicate content of cement on concrete durability has long been a topic of discussion in the literature. The objective of this investigation was to determine whether increasing tricalcium silicate content of cement has a negative effect on concrete sulfate durability. Several mill certificates were reviewed to select cements with similar tricalcium aluminate content and variable tricalcium silicate contents. Cements selected for this study were randomly labeled as cements C, D, D2, E, and P. The following properties were assessed for the as-received cements: Blaine fineness, particle size distribution, chemical oxide content, and mineralogical content. Three different methods were employed to determine the mineralogical composition of the as-received cements: Bogue calculation, internal standard method, and Rietveld refinement analysis. Despite the attempt to select cements with similar composition, it was determined that the as-received cements had compositional differences other than their C3S content. These cements had a variable tricalcium aluminate and alkali content, as well as differences in the amount and form of calcium sulfates. In order to eliminate these variances, doped cements were prepared by increasing the C3S content of the as received cements to 69 % by Bogue calculation. Durability of as-received cements and doped cements was assessed through several measurements including length change, compressive strength, and phase transformation in sodium sulfate solution. For as-received cements, compressive strength of mortar cubes stored in saturated lime solution was evaluated as well. Semiquantitative x-ray diffraction analysis and scanning electron microscopy observations were performed on mortar bars to evaluate the relative amounts and morphology of the hydrated phases. It was concluded at the end of this study that cements with high tricalcium silicate content generally have poor durability in sodium sulfate environment. All the cements experienced higher expansion with increased C3S content. High C3S content combinedwith high C3A content was particularly detrimental to mortar resistance to sodium sulfate attack.

This diploma thesis focuses on diagnostics of bridge structures. First part of this diploma thesis will focus on theoretical knowledge about bridge structures and common diagnostic techniques suited for examining material priperties of samples taken from structure. Second part of this thesis will focus on practical use of experiments used in diagnostic branch. I will be doing visual observation of concrete structure followed by experiments on core samples. End of thesis will be evaluating structure from global perspective and will deliver specific sugestions for renovation.

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The Concrete Masonry Association of California and Nevada in conjunction with Brigham Young University devised a masonry prism testing scheme to aid in the determination of whether prisms constructed with grouts possessing high levels of supplemental cementitious materials could meet minimum masonry compressive strength requirements. ASTM standards, identical to that of concrete, place restrictions on quantities, by weight, of supplemental materials that can replace ordinary Portland cement. For an all fly ash replacement, up to 40% of Portland cement can be replaced while up to 70% can be replaced by a fly ash-slag combination. Research is focused on class F fly ash and ground granulated blast furnace slag replacing Portland cement in larger quantities. Manufacturing grouts with increasing incremental amounts help to establish higher use limitations associated specifically with masonry grout. Masonry prisms, concrete masonry units, type M mortar, and variations of grout were tested for their respective compressive strengths at age intervals of 14, 28, 42, 56, and 90 days. Grouts were designed to support the discussion of whether non-traditional grouts can achieve acceptable masonry compressive strength in prisms while not possessing adequate grout compressive strength. The control grout consisted of one mix design containing a cementitious materials content of 100% Portland cement. Three grouts replaced Portland cement with fly ash and three grouts replaced Portland cement with a fly ash-slag combination without modifying the cementitious material weight contribution. Class F fly ash replaced Portland cement at rates of 45%, 55%, and 65%. Class F fly ash-ground granulated blast furnace slag combinations replaced Portland cement at rates of 65%, 75%, and 85% where the combinations consisted of 25% fly ash and 40%, 50%, and 60% slag. Results indicate that all prisms exceeded the 10.3 MPa (1500 psi) minimum compressive strength requirements before the mandated 28-day age period. Neither 55% and 65% fly ash replacements nor the 85% fly ash-slag combination achieved grout strength minimums at the typical specified age. The grout mixtures manufactured with exceeding addition rates which attained greater than the minimum strength at the 28-day age were the 45% fly ash and 65% and 75% fly ash-slag combination. All grouts did, eventually, extend their strength gain beyond 13.8 MPa (2000 psi) through the course of testing and all but 65% fly ash achieved this strength within 42 days.