The work deals with the development of new types of gas and waterproof tight coatings based on secondary crystallization of cement, using industrial waste as secondary raw material in the formulation of new recipes.

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Akrylbaserat bencement är den gyllene standarden vid ryggförstärkningsförfaranden. Modifiering av akrylbencement med linolsyra har resulterat i attraktiva egenskaper vilka möjliggör lättare hantering för kirurger och minskar efterföljande komplikationer såsom närliggande ryggradsfrakturer. Även om de attraktiva egenskaperna hos linolsyramodifierat bencement är kända är ännu förståelsen för hur linolsyra påverkar egenskaperna outforskade. Som en komponent i bencement måste linolsyra steriliseras innan den används i bencement. Det finns emellertid oro för att autoklavsterilisering av linolsyra orsakar nedbrytning. Dessutom är det oklart vad som händer med linolsyra i härdat bencement över tid. I detta examensarbete utvärderades steriliserad och osteriliserad linolsyra. Linolsyra blandades med olika komponenter som finns i bencementet såsom aktivator, initiator, monomer och inhibitor, i närvaro och frånvaro av lösningsmedel. De efterföljande förändringarna studerades genom 1H NMR och UV-VIS. Resultaten visade att linolsyra bryts ned av sterilisering och oxidation. Oxidationen av linolsyra berodde på sterilisering, temperatur, lösningsmedel och mängden syrexponering. Det bekräftades genom 1H NMR och UV-VIS att linolsyra reagerade (steriliserad och osteriliserad) med aktivatorn, initiatorn och monomeren. Dessa reaktioner kan minska tillgängligheten av komponenterna för in situ-polymerisation av monomeren, och därmed förändra bencementens egenskaper, vilket i sin tur bidrar till lättare hantering under förstärkningsförfarandet och reducerar intilliggande ryggradsfrakturer efter operation. / Acrylic bone cement is the gold standard in vertebral augmentation procedures. Modification of acrylic bone cement using linoleic acid has resulted in attractive properties that enable convenient handling by surgeons and reduce follow-up complications such as adjacent vertebral fractures. Even though the attractive properties of linoleic acid-modified bone cement are acknowledged, the understanding of how it imparts those properties remain unexplored. As a component in bone cement, linoleic acid needs to be sterilized before its use in bone cement. However, there are apprehensions whether autoclave sterilization of linoleic acid causes degradation. In addition, it is unclear what happens with linoleic acid in hardened bone cement over time.  In this thesis, sterilized and unsterilized linoleic acid were evaluated alone and treated with different components of the bone cement such as activator, initiator, monomer, and inhibitor, in the presence and absence of solvent, and the ensuing changes were monitored through 1H NMR and UV-VIS. The results showed that linoleic acid degraded due to sterilization and oxidation. The oxidation of linoleic acid depended on sterilization, temperature, solvent, and the amount of oxygen exposure. As confirmed through 1H NMR and UV-VIS, linoleic acid (sterilized and unsterilized) reacted with the activator, initiator, and monomer. These reactions could reduce the availability of the components for the in-situ polymerization of the monomer, thus altering the properties of the bone cement including convenient handling during the operation and reduced adjacent vertebral fractures post the operation.

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This thesis has determined that using fly ash as a mineral filler in asphalt pavements can help strengthen and reduce asphalt moisture damage. Also, dynamic shear rheometer tests show that these additives have a stiffening effect on asphalt binder. Moisture related damage is considered one of the main causes of asphalt pavement failure. As water infiltrates a layer of asphalt, it slowly strips away asphalt binder, weakening the aggregate/binder bond. This process, combined with the cyclic loading of traffic, can lead to several different types of asphalt failure including rutting, raveling, bleeding, and cracking. For several decades, research has been conducted to find a solution to this problem. Currently in practice, hydrated lime and a variety of amine-based chemicals are being used as anti-stripping agents. However, as an emphasis towards sustainability has increased, waste products are now being investigated for this purpose. This thesis investigated the anti-stripping effectiveness of two waste products: fly ash and cement kiln dust (CKD), and compared them with hydrated lime and an amine-based chemical additive. The results indicate that class C fly ash can be used as an asphalt anti-stripping additive; however it is more costly than lime or amine chemicals.

A laboratory test program was undertaken to evaluate a series of engineering properties over a range of soil types; amendment types and addition rates; and moisture contents to enhance understanding of the engineering significance of polymer amendment. Four soils were manufactured and tested with varying ranges of fines and plasticity. A proprietary elastic copolymer was tested at addition rates of 0.5% to 2.5% (dry weight basis). Cement was tested at addition rates of 1% to 4%. Lime was tested at an 8% addition rate. Water addition rates ranged from 4% dry of optimum to 4% wet of optimum. Engineering properties determined throughout the test program included dry unit weight / moisture content relationships through compaction tests; shear strength through unconfined compression strength tests and direct shear tests; durability through freeze-thaw and wet-dry durability tests; and stiffness through resilient modulus tests and through interpretation of the unconfined compression and direct shear test results. The addition of polymer altered the optimum moisture content of the soils. Change in optimum moisture content ranged from 0.51 to 1.27 times the control water demand. The dry unit weight of polymer amended specimens ranged from 0.97 to 1.01 times their respective control dry unit weight. The peak strength of polymer amended specimens ranged from 1.02 to 18.4 times the control strength. The peak wet-dry and freeze-thaw durability of polymer amended specimens ranged from 6.8 to 10.8 times the control durability. The addition of polymer increased the peak initial stiffness of specimens to approximately 3 times the control stiffness. However, the stiffness was reduced to 0.68 times the control stiffness with dynamic repeated loading through the resilient modulus test. The polymer addition rate required to achieve peak engineering performance ranged from 0.5% to 2.5%, based on soil type. Polymer modified the engineering properties of soil through physical bonding. The amount of polymer required to modify the engineering properties was directly related to specific surface and soil particle coating thickness. It was determined that polymer amendment had an optimal addition rate that resulted in the greatest increase in engineering parameters. The addition rate was optimum when polymer was applied at rates high enough to sufficiently coat all soil particle surfaces, but at rates low enough that it did not cause additional particle separation. Overall, polymer amendment of soil improved or maintained all tested engineering parameters, except the resilient modulus, of all soils. Polymer amended soils displayed a reduced performance compared to cement amended soils, and an improved performance compared to lime amended soils.

While cement treatment is a proven method for improving the strength and durability of soils and aggregates, cement hydration causes shrinkage strains in the cement-treated base (CTB) that can lead to reflection cracking in asphalt surfaces. Cracking may then cause increased pavement roughness and lead to poor ride quality. The overall purpose of this research was to utilize data collected through the Long-Term Pavement Performance (LTPP) program to investigate the use and classification of CTB layers and evaluate the relative impact of cement content on the development of roughness and cracking in asphalt concrete (AC) pavements constructed using CTB layers. The data included 52 LTPP test sites, which represented 13 different states and one Canadian province, with cement contents ranging from 3.0 to 9.5 percent by weight of dry aggregate. Statistical procedures were utilized to identify the factors that were most correlated to the observed pavement performance and to develop prediction equations that transportation agencies can use to estimate the amount of roughness for a given pavement at a given age and the amount of distress associated with a particular crack severity level for a given pavement. The data collected for this study suggest that wide ranges of cement contents are used to stabilize soils within individual American Association of State Highway and Transportation Officials soil classifications. The data also suggest that CTBs comprising flexible pavement structures are constructed mainly on rural facilities. A backward-selection model development technique was used to develop sets of prediction equations for roughness and cracking. Age, AC thickness, CTB thickness, and cement content were determined to be significant predictors of International Roughness Index, while age, air freezing index, AC thickness, CTB thickness, cement content, and traffic loads in thousands of equivalent single-axle loads were determined to be significant predictors of low-severity, medium-severity, and high-severity block, fatigue, longitudinal (wheel-path and non-wheel-path), and transverse cracking in AC pavements constructed using CTB layers. Investigation of the relationships between CTB modulus and the development of roughness and cracking is recommended for further study.

The primary purposes of this research were to identify construction factors most correlated to specific mechanical properties of cement-treated base (CTB) layers and to determine which construction factors exhibit comparatively high variability within individual construction sections of the two pavement reconstruction projects included in this study. In addition, differences between construction sections tested in this research were evaluated. The research focused on the construction of CTB layers in two pavement reconstruction projects in northern Utah, one along Interstate 84 (I-84) near Morgan and one along U.S. Highway 91 (US-91) near Richmond. The significant predictor variables associated with California bearing ratio (CBR), Clegg impact value (CIV), 7-day unconfined compressive strength (UCS), and 28-day UCS at the I-84 sites include reclaimed asphalt pavement (RAP) content; cement content; amounts of aggregate particles finer than the No. 8, No. 50, and No. 200 sieves; 7-day moisture content, and 28-day moisture content. The significant predictors of the same response variables on US-91 were in-situ moisture content, cement content, amount of aggregate particles finer than the No. 50 sieve, time between mixing and compaction in the field, dry density in the field, 7-day dry density, 7-day moisture content, 28-day dry density, and 28-day moisture content. The factors that were found to be the most variable on both I-84 and US-91 were CBR, cement content, time between mixing and compaction in the field, and time between mixing and compaction for each of the manually compacted specimens. On I-84, 16 of 27 factors were found to be significantly different between the sites, while 17 of 26 factors were found to be significantly different between the sites on US-91. The results of this research suggest that tighter specifications are warranted with respect to RAP content, cement content, and time between mixing and compaction. Concerning full depth recycling (FDR) projects, milling plans should be utilized to achieve improved uniformity in RAP content, and inspection protocols for encouraging improved control of cement content should be implemented during construction to ensure high-quality work. Compaction should be performed as soon as possible after mixing to minimize the adverse effects of cement hydration on the ability to achieve maximum dry density in the field.

Light-weight aggregate has been used successfully for structural and non-structural applications, and its most common use has been in light-weight concrete. Limited research has been done on light-weight grout though and there are no standards in place. The research performed in this study is intended to increase the knowledge of light-weight grout specifically made with expanded shale aggregate. The research presented herein is a pilot study and consists of preliminary aggregate and grout testing that resulted in the mix design of six grout types: three fine grout designs and three coarse grout designs. Conventional normal-weight aggregate was employed in the first grout mix. A light-weight aggregate batch was made with the same material proportions, as well as the same target water-cement (w/c) ratio and cement content. The weight of the cement was increased by 30 percent in the third grout type of each set to determine the effect on strength. The slump, component temperature, unit weight, air content, segregation, cement content, w/c ratio, and compressive strength for each grout type was gathered throughout testing. Correlations between grout testing results are examined and discussed. In addition, the effectiveness of expanded shale grout, other light-weight grouts, and normal-weight grout with respect to compressive strength to cement content ratio are determined. Results of the testing show that all six grout types studied in this research reached the minimum 28-day strength of 13.8 MPa (2000 psi) ASTM standard. In addition, the results indicate that the cement content in expanded shale light-weight grout would need to be increased to reach comparable compressive strengths to that of the normal-weight grout. The comparison between the compressive strength to cement content ratio of the different grouts indicate that normal-weight grout is more efficient. In addition, light-weight grout made with blast furnace slag grout is slightly more efficient than that made with expanded shale; however, this observation was only possible after several crucial assumptions were made about an existing blast furnace slag study. These strength-cement ratios do not account, however, for the benefits of reduced dead loads, improved thermal insulation, and improved sound insulation that could potentially influence the choice of the material used in and the life-cycle cost of the construction. Additional research should be done to verify the results of the ratios and the assumptions made herein. Furthermore, a life-cycle analysis needs to be conducted before a definite conclusion is made about which type grout is more efficient.