Külmutus- ja sulatustsüklite mõju asfaltsegudele

Antud lõputöö eesmärgiks oli uurida sulatava ja külmutava temperatuuri perioodilise vaheldumise mõju asfaltsegudele, imiteerides kevadist olukorda eesti teedel., kus kevadine niiske ning soolane teedel esinev keskkond peab pidama vastu liiklusele ning naastrehvide mõjule. Kuna asfaltsegudele külmakindluse katsetamist sellisel kujul ei teostata, siis on külmutusprotsessi teostamine täielikult eksperimentaalne, erinevalt teistest lõputöös kirjeldatud katsetest, mida teostatakse vastavate standardite kohaselt. Kuigi selge on et kulumiskindluse poole pealt antud keskkond kindlasti nõrgendab tee katendit, siis pole katsetulemuste põhjal võimalik ühtegi selget järeldust teha. Pole kindel, kas antud katsetamise meetod antud mõjude uurimiseks sobilik on. Juhul kui jätkata antud teema uurimist samal viisil, siis leian, et uuritavate segude kogust tuleks märgatavalt suurendada ning katseperioodi pikendada.

The aim of graduation thesis The Effects of Freezing and Thawing Cycles to Asphalt Mixtures is to research the effect of freezing and thawing cycles, in a humid environment with NaCl salt present, to asphalt mixtures resistance to abrasion by studded tires and susceptibility to deform and develop rutting. This topic is very actual in Estonian road construction as in the spring time temperatures fluctuate daily around zero degrees Celsius and as the majority of the traffic is still using studded tires during that period, I was curious if rutting and abrasion of the road surface in spring time was an issue, that should be taken into consideration when planning the roads in the future. A brief description of what tests are preformed, in order to achieve the results described in this thesis. As the effects of freezing and thawing cycles to asphalt mixtures is not actually tested, and thereby is not regulated by any European standard, the means of testing it is purely experimental, unlike the other tests described in this thesis. The results of the findings are that the asphalt suffers greatly in its resistance to abrasion by studded tires, but I also found, that mi testing was to preliminary to make definitive conclusions and the wheel tracking test was only starting to show some results on the final test specimens. As a result I there by find, that this test method may not be suitable for this research. At very least the testing period should be greatly extended and the variety of testable mixtures expanded.