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Rupnikova linija je sistem vojaških utrdb, postavljenih na Rapalski meji, ki naj bi pred drugo svetovno vojno takratno Jugoslavijo varovala pred vdorom Italijanskih sil. Sestavlja jo več kot 4000 armiranobetonskih vojaških objektov, zgrajenih med letoma 1935 in 1940. Delimo jo na (visoko ležečo) zgornjo in (nizko ležečo) spodnjo linijo. Ker bunkerji v svoji življenjski dobi še niso bili sanirani in so nekateri v slabem stanju, smo za izbrane bunkerje na podlagi predhodnih raziskav v okviru magistrske naloge sprojektirali beton, ki naj bi bil primeren za njihovo sanacijo. V okviru raziskave smo preverjali, če so mehanske lastnosti replik betona primerljive z mehanskimi lastnostmi historičnega betona. Vzorce historičnega betona smo izvrtali iz izbranih bunkerjev Rupnikove linije in jih narezali na valje premera 95 mm in višine 100 mm. V raziskavi smo uporabili 9 vzorcev zgornje in 6 vzorcev spodnje linije. Za primerjavo smo v laboratoriju pripravili dve mešanici, repliki historičnega betona. V prvo mešanico, ki naj bi bila namenjena sanaciji izbranih bunkerjev zgornje linije, je bil vgrajen apnenčev agregat, v drugo, ki naj bi bila namenjena sanaciji izbranih bunkerjev spodnje linije, pa smo vgradili dolomitni agregat. Iz vsake mešanice smo pripravili 6 kock dimenzij 100 × 100 × 100 mm in 6 kock dimenzij 150 × 150 × 150 mm, skupaj 24 vzorcev. Vzorcem smo na podlagi meritev s hidravlično stiskalnico najprej določili izhodiščne vrednosti tlačne trdnosti in statičnega modula elastičnosti. Po tem smo vzorce izpostavili 30 ciklom zmrzovanja in tajanja s prisotnostjo talilnih soli. Med ciklanjem smo z ultrazvokom spremljali spremembo tlačne trdnosti in dinamičnega modula elastičnosti, hkrati pa smo jim merili izgubo mase. Na podlagi rezultatov smo se opredelili glede ustreznosti betonskih mešanic za sanacijo z vidika tlačne trdnosti, modula elastičnosti in zmrzlinske odpornosti. Rupnik fortification line is a system of military fortifications on the Rapallo border, built just before the second world war. Its purpose was to defend the Kingdom of Yugoslavia from an attack by Italian forces. The fortification line consists of about 4000 military structures built between 1935 and 1940. Most of the structures were made with reinforced concrete and were split between the upper line (high positions) and the lower line (low positions) made of different concrete mixtures. Some of the structures are in a terrible state and in need of restoration, so we designed a concrete mix suitable for their restoration based on the research included in this thesis. The study compared the mechanical and physical properties of the replicated concrete samples to the samples of historic concrete gained from the structures on the fortification line. Samples of concrete were taken from selected fortifications and shaped into cylinders measuring 95 mm in diameter and 100 mm in height. Of all the samples 9 were taken from the bunkers of the upper line and 6 were taken from those of the lower line. Two different mixtures of concrete were prepared. For the restoration of the upper line, limestone aggregate was used, and for the restoration of bunkers of the lower line, dolomite aggregate was used. Each mixture was used to produce six 100 × 100 × 100 mm cubes and six 150 × 150 × 150 mm cubes, 24 in total. Using a hydraulic press, we set a base value for the concrete specimens' compressive strength and modulus of elasticity. The samples were then exposed to 30 freeze-thaw cycles, with the presence of chlorides, where compressive strength and dynamic modulus of elasticity were measured using ultrasound. Loss of mass was also measured at the same time. The results were used as the basis for determining the suitability of the concrete mixtures for the restoration of the structures on the Rupnik military line.

V diplomski nalogi je predstavljen proces izdelave toplotno izolacijskih plošč narejenih iz odpadnega poliesterskega (PET) netkanega tekstila. Plošče so bile narejene s stiskanjem in segrevanjem zmletega odpadnega filca v preši z ogrevanimi stiskalnimi ploščami. Prvih nekaj plošč je bilo izdelanih poskusno z namenom izboljšanja procesa izdelave. Kasneje je bilo zdelanih 35 plošč, ki se med seboj razlikujejo po debelini, gostoti nasutja in po tem, da nekatere vsebujejo vodno steklo, ostale pa ne. Devetnajst plošč je bilo v nadaljevanju podrobneje analiziranih. V tej fazi je bila izmerjena njihova toplotna prevodnost, požarna odpornost in zvočna izolativnost. S primerjanjem dobljenih rezultatov meritev je je bilo ugotovljeno, da ima največji vpliv na toplotno prevodnost gostota samih plošč. Gostejša kot je plošča, višjo ima toplotno prevodnost, kar pomeni, da je njena toplotna izolativnost slabša. Vsebnost vodnega stekla vpliva na toplotno prevodnost, saj so plošče z dodanim vodnim steklom imele višjo toplotno prevodnost kakor plošče z enako gostoto brez vodnega stekla. Na toplotno prevodnost plošč brez dodanega vodnega stekla vpliva tudi končna debelina plošč, saj z večanjem debeline plošč narašča njihova toplotna prevodnost. Pri ploščah z dodanim vodnim steklom je vpliv debeline na toplotno prevodnost zanemarljiv. Toplotna prevodnost plošč nižje gostote je s svojimi lastnostmi konkurenčna nekaterim obstoječim izolatorjem na trgu. Toplotna prevodnost plošč, ki so bile testirane znaša od 0,044 do 0,061 W/mK. Na absorpcijo zvoka plošč imata pozitiven vpliv višja gostota in dodatek vodnega stekla. Ugotovljeno je bilo tudi, da dodatek vodnega stekla, ki je sam po sebi negorljiv negativno vpliva na odziv plošč izpostavljenih odprtemu plamenu. The thesis describes the process of manufacturing thermal insulation panels made from non-woven polyester (PET) textiles. Panels were made by compressing and heating the shredded non-woven felt in a heated platen press. The first few trial panels were made with manufacturing process improvement in mind. Subsequent 35 panels were made in different thickness and density of fill, some of them with and some without added water glass. Nineteen panels were analyzed in detail. At this stage their thermal conductivity, sound absorption and fire resistance were measured. The comparison of the obtained measurement results demonstrated that the density of the panels has the greatest impact on thermal conductivity. The denser the panel, the higher its thermal conductivity, which indicates worse thermal insulation properties. Thermal conductivity is also affected by presence of water glass, since panels with added water glass had higher thermal conductivity compared to the panels of the same density without water glass. Thermal conductivity of the latter depends on the final thickness of the panels as their thermal conductivity increases proportionally to their thickness, whereas the impact of thickness on thermal conductivity of panels with added water glass is negligible. Thermal conductivity of lower density panels is competitive with some of the existing insulators on the market. Thermal conductivity of the tested panels ranged from 0,044 to 0,061 W/mK. Water glass and higher sample density have a positive influence on the sound insulation properties of the panels. It has also been concluded that that the addition of water glass, which itself is non-combustible, has a negative effect on the fire resistance properties of the panels.