M.Ing. (Mechanical Engineering) / An investigation was made to determine the feasibility of using existing international developed compositions of furfuryl alcohol polymer concrete in South African applications. Problems were encountered with these formulations and modifications were required in order to enhance the application possibilities of the material. After these modifications were made, tests were conducted to determine the effects of temperature, humidity, specimen size and variations in constituent quantities on the polymerisation reaction and properties of the material. Engineering characteristics, such as, compressive strength and durability were investigated and large scale field tests were performed to demonstrate the feasibility and simplicity of using polymer concrete. The final mix design selected for use in South Africa, polymerised within 20 minutes obtaining a compressive strength of 20 MPa in that period. This material proved stable under adverse chemical conditions and was able to withstand elevated temperatures of up to 200°C. Tests on road pothole rehabilitation slabs showed that polymer concrete can resist high stresses successfully under repeated loads and can be installed in less than 30 minutes in order to minimize traffic hold-ups. Furfuryl alcohol polymer concrete can be made at a cost of approximately 50c/kg and proves to be cost-effective when compared with epoxies.

Thesis (M.S. in civil engineering)--Washington State University, December 2008. / Title from PDF title page (viewed on June 19, 2009). "Department of Civil Engineering." Includes bibliographical references (p. 93-94).

Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains x, 103 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 84-87).

Geopolymer concrete (GC) is a sustainable construction material and a great alternative to regular concrete. GC is a zero-cement material made from a combination of aluminate, silicate and an activator to produce a binder-like substance. This investigation focused on the effects of wet and dry cycles on the strength and durability of fly ash-based recycled aggregate geopolymer concrete (RAGC). The wet-dry cycles were performed approximately according to ASTM D559 standards. RAGC specimens with nearly 70% recycled materials (recycled aggregate and fly ash) achieved a compressive strength of approximately 3600 psi, after 7 days of heat curing at 60ºC. Although the recycled aggregate is prone to high water absorption, the compressive strength decreased by only 4% after exposure to 21 wet-dry cycles, compared to control specimens that were not exposed to the same conditions. Accordingly, the RAGC material developed in this study can be considered as a promising environmentally friendly alternative to cement-based regular concrete. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Environmental factors and physical properties of latex modified concrete (LMC) are hypothesized to contribute to early age cracking in bridge deck overlays. Cracking permits the ingress of moisture and aggressive solutions into the substrate and may contribute to other subsequent distresses. Understanding the material properties and mechanisms involved is necessary to minimize these distresses. This research consisted of a two part study: first, the development of LMC strength and fracture properties at ages ranging from 5 hours to 28 days was studied, and secondly, the effects of the environment on LMC distresses were modelled. Environmental conditions: temperature, solar energy, and wind speed were determined from weather records. A fracture mechanics based model, the Fictitious Crack Model (FCM), incorporating finite element analyses and superposition techniques was employed with material properties from the first part of study on LMC performance. Different bilinear strain softening diagrams were used to predict fracture performance at different ages. The predictions agreed well with the test data. The impacts of temperature differentials on crack development were studied. The shrinkage effect was also indirectly incorporated through the temperature analysis. The material properties study indicated significant changes in strength, deformability and fracture properties, particularly during the early age. The developments differ slightly from conventional concrete. Test results indicated a significant improvement in reducing and bridging microcracks, especially in the prepeak-load region. Fracture toughness and deformability increased significantly with time. Fracture energy varied from 2.3 to 133.1 N/m, depending on age, and to some degree, on notch depth ratio. In the second stage, the FCM provided a reasonable prediction for crack initiation and propagation when only temperature effects are of concern. Age, surface conditions and structural restraint strongly affect crack resistance of the overlays. Only slight effects were observed from the overlay thickness in the study range (51-76 mm). Shallow preexisting cracks possibly reduce the crack resistance of the overlay about 30 percent. A prolonged moist cure for 48 hours after placing is suggested to reduce the risk of cracking. With available environmental information, it is possible to develop guidelines for appropriate environmental conditions for LMC bridge deck construction to minimize the risk of early age cracking. / Graduation date: 1997

Thesis (M.S. in civil engineering)--Washington State University, December 2009. / Title from PDF title page (viewed on Feb. 4, 2010). "Department of Civil Engineering." Includes bibliographical references (p. 134-135).

This is partly because the requirements for such an ultimate material change with people’s perception about its properties as well as its environmental impact. Thus, the once-believed ultimate Portland cement binder is now becoming unacceptable for a number of reasons including poor durability as well as severe environmental impact during production. Thus, an improved mineral binder is required by modern society to serve the same purposes as the existing Portland cement binder, as well as to reduce the current environmental impact caused by Portland cement production. / Geopolymerisation is such a ‘green’ technology capable of turning both natural ‘virginal’ aluminosilicates and industrial aluminosilicate wastes, such as fly ash and blast furnace slag, into mechanically strong and chemically durable construction materials. However, the source materials for geopolymer synthesis are less reactive than Portland cement clinkers and the chemical compositions of these source materials can vary significantly. Consequently, product quality control is a major engineering challenge for the commercialisation of geopolymers. / This thesis is therefore devoted to the mechanistic understanding of the interfacial chemical interactions between a number of natural and industrial aluminosilicates and the various activating solutions, which govern the reactivity of the aluminosilicate source materials. The effects of activating solution alkalinity, soluble silicate dosage and anionic contamination on the reactivity of the aluminosilicate source materials to produce geopolymeric binders, as well as their bonding properties to natural siliceous aggregates for concrete making, are examined. In particular, a new set of novel ‘realistic’ reaction models has been developed for such purposes. These reaction models have been further utilised to develop a novel analytical procedure, which is capable of studying geopolymerisation on ‘real’ geopolymers in situ and in real time. This novel procedure is invaluable for the total understanding of geopolymerisation, which is in turn vital for effective geopolymer mix designs.

Thesis (Ph.D.)--University of Melbourne, Dept. of Chemical Engineering, 2003. / Typescript (photocopy). Includes bibliographical references.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 179-181). Also available via the Internet