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dc.contributor.advisorRyabchikov, Alexander
dc.contributor.authorUdras, Sten-Maikel
dc.date.accessioned2016-05-18T08:04:15Z
dc.date.available2016-05-18T08:04:15Z
dc.date.issued2016
dc.identifier.urihttp://hdl.handle.net/10492/2522
dc.description.abstractAegade jooksul korraldatud katsete käigus on uuritud teraskiudude mõju kiudbetooni surve-, painde-, nihke-, tõmbe- ning väändetugevusele. Antud magistritöö eesmärgiks oli uurida, kuidas mõjutavad teraskiudude kuju ja omadused kiudbetooni jääkpaindetugevust ning kiudude jagunemist betoonis. Samuti sooviti välja selgitada, milline kiu omadus avaldab kõige suuremat mõju kiudbetoonelementide jääkpaindetugevusele. Töö eesmärkide saavutamiseks korraldati paindekatsed vastavalt standardile ASTM C1550 – 12a ning survekatsed vastavalt standardile EVS-EN 12390-3:2009. Kokku valmistati 36 katsekeha, millest 18 olid ümarplaadid läbimõõduga 800 mm ja paksusega 75 mm paindekatsete läbi viimiseks ning 18 olid kuubid mõõtmetega 150×150×150 mm survekatsete läbi viimiseks. Katsekehad jagunesid kuude seeriasse, millest viies kasutati erinevat tüüpi teraskiudusid ning ühes teraskiudusid koos basaltkiududega. Esmalt läbi viidud survekatsete tulemused näitasid, et erinevate seeriate katsekehades kasutatud betoon ei saavutanud ühesugust survetugevust. Antud tulemusi võeti arvesse paindekatsete tulemuste analüüsi juures. Paindekatsetel saadud väärtused näitasid, et kõige suurem kiudbetooni keskmine jääkpaindetugevus saavutati HE 1/60 tüüpi teraskiudude kasutamisel ning kõige väiksem Tabix 90/35 teraskiudude kasutamisel, millest järeldub, et pikemate teraskiudude kasutamine suurendab oluliselt kiudbetoonelementide jääkpaindetugevust. Kiudude suurem läbimõõt tulemustele positiivselt ei mõjunud. Painutatud otstega (hooked-end) teraskiudude kasutamisel oli kiudbetooni jääkpaindetugevus kõrgem kui laineliste (wavy) kiudude kasutamisel. Vaadates kõiki paindekatsete käigus saadud tulemusi ning ümarplaatide purunemispindasid, võib järeldada, et kõige suuremat mõju kiudbetooni paindetugevusele avaldavad kiudude pikkused ning nende jagunemisele mõjub kõige rohkem saledusarv. Kõrgema saledusarvuga kiud jaotuvad betoonis paremini. Antud valdkonna edasistes eksperimentaaluuringutes peab läbi viima lisakatseid, mille käigus peaks suurendama seerias olevate katsekehade arvu ning uurima basaltkiu mõju teraskiudbetooni jääkpaindetugevusele.est
dc.description.abstractOver time, tests have been performed to study the impact of steel fibres on the compressive, flexural, shear, tensile, and torsional strengths of fibre reinforced concrete. The aim of the present Master´s thesis was to investigate the effect of the shape and properties of steel fibres on the residual flexural strength and the distribution of fibres in concrete. It was also intended to point out which fibre property has the greatest impact on the residual flexural strength of fibre concrete elements. To achieve the objectives, bending tests were performed in accordance with the standard ASTM C1550 – 12a, and compression tests according to the standard EVS-EN 12390- 3:2009. A total of 36 specimens were prepared, 18 of which were circular plates with a diameter of 800 mm and a thickness of 75 mm to carry out bending tests and 18 cubes with the measures of 150×150×150 mm for compression testing. The specimens were divided into six series, five of which contained different types of steel fibres, and one contained steel fibres mixed with basalt fibres. The results of the compression tests indicated that the concrete used in the specimens in different series did not reach the same compressive strength. This was taken into account when analysing the results of the bending tests. The results of the bending tests revealed that the highest average residual flexural strength of fibre reinforced concrete was achieved when using HE 1/60 steel fibres, and the lowest strength was when using Tabix 90/35 steel fibres. Thus, it can be concluded that the residual flexural strength of fibre concrete elements is significantly increased by longer steel fibres. A larger diameter of fibres did not affect positive results, but their shape did. Hooked-end steel fibres revealed higher flexural strength than wavy fibres. When studying all the results obtained during the bending tests and the fracture areas of the circular plates, it can be concluded that the length of the fibre has the most significant impact on the flexural strength of fibre reinforced concrete; and their distribution is affected mostly by an aspect ratio. Fibres with a higher aspect ratio were better distributed in concrete. Based on the results of this research, new tests could be carried out, in the process of which the amount of specimens in series should be greater. In addition, the impact of basalt fibres on the residual flexural strength of steel fibre reinforced concrete should be examined as well.eng
dc.subjectmagistritöödest
dc.subjectterasest
dc.subjectkiudbetoonest
dc.subjectpurunemispinnadest
dc.subjectjääkpaindetugevusest
dc.titleTeraskiudude kuju ja omaduste mõju kiudbetoonelementide paindetugevuseleest
dc.title.alternativeThe impact of shape and properties of steel fibres on the flexural strength of fibre reinforced concrete elementseng
dc.typeMaster Thesis
dc.date.defensed2016-06-02


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