DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 8-9/1959 str. 71 <-- 71 --> PDF |
ispitano mnoštvo raznih podataka iz literature, koji se najprije provjeravaju u praksi i onda, ukoliko je potrebno, nadopunjavaju. Tek nakon ispitivanja moći će rezultati biti predani operativi u obliku priručnika. Dovršeni su radovi na impregnaciji pragova s izbušenim tirfonskim rupama, zatim na zaštiti tirfonskih rupa koje se buše neposredno prije ugradnje pragova i napokon jedan dio kemijskih i mikoloških is.pitivanja raznih vrsta uljnih mješavina. Kako se vidi problem je željezničkih pragova kod nas nešto drugačiji nego na evropskom Zapadu. Za sada se ne postavlja pitanje deficitarnosti drvnih masa, ali se zato postavlja pitanje štednj e naših rezerva. Težište se naših nastojanja ima usredotočiti na racionalno korištenje autohtone bukovine, a to je moguće tek onda, kada budemo točno poznavali njezina fizikalna i mehanička svojstva u našim uslovima, i to posebno za nizinske a posebno za planinske sastojine. Ne može se reći, da u tom pogledu nije do sada ništa učinjeno. Dapače, već raspolažemo s velikim brojem snimanja i biometrički obrađenim materijalima. Ali to su za naše prostrane komplekse tek počeci i u najboljem slučaju prvi fragmentarni rezultati istraživanja, koje još ne možemo praktički koristiti. LITERATURA: 1) Egg-Garni m H.: Die Holzschwelle in der Schweiz., Intern. Holzmarkt, Nr. 10. Wien 1954. 2) Holz-Mitteilungen : Holzschwelle Oder Stahlbetonschwelle, Holz als Rohund Werkstoff, Heft 1, Berlin-Gottingen-Heidelberg 1954. 3)Gregori č F.: Problematika zaštite drveta impregnacijom s naročitim .osvrtom na električne stubove Slovenije, Korozija, Zaštita materijala, br. 12, Beograd, 1957. 4) II faut defendre la traverse en bois. Le bois, 1´officieJ du bois et des industries du bois, Paris, Mai 1954. 5} Morat h E : La traverse de chemin de fer, son histoire et sa place dans V evolution dies techniques du bois, Revue du bois, No 12, Paris 1957. 6) Nowa k A.: 1st die Holzschwelle ersatzbediirftig? Intern. Holzmarkt, Nr. 10. Wien 1954. THE DEVELOPMENT AND ROLE OF THE RAILWAY SLEEPER The author presents the most striking historical data on the development of the railway sleeper. On the basis of this material he concludes that the mere fact that the wooden sleeper has retained itself through more than a hundred years is indicative of the fact that the engineering practice has not been aWe to discover a more suitable equivalent. Substitutes of iron and concrete have not succeeded to supersede wood. Through the analyses of the development of impregnation he reaches the conclusion that owing to the application of the economical Rueping empty-cell process Beechwood ´surpasses as to the durability all other European species. It is very imporant for the development of the Yugoslav railway traffic, because the Beech is the dominant tree species in Yugoslaw forests. When discussing the development of the wood pathology he especially points out the year 1902, when paraleli with the first successes in the discovery of the causal organisms of parasitic infestations was brought up also the most economical method of preservation. Eventually he dwell9 upon the problems of Yugoslav production of Beech sleepers, which, true, has at its disposal a sufficient volume of wood but must import large amounts of tar oil (ca. 16.000 tons per annum). The impregnated sleepers in the Yugoslav railways´ display a durability of almost 14—17 years which requires on an average a replacement of ca. 1.3 millions of sleepers per annum (the total number of built- in sleepers being 21.5 million pieces). The reasons for such a low durability lie on the one hand in an inadequate handling before impregnation, and on the other in uncontrolled mixtures of imported oil preservatives. Thus also are defined the tasks of the scientific investigations. They include: elimination of incipient decay, possibility of impregnating the pieces in the inital stage of decay, as well as the expermental impregnation with different mixtures of indigenous and imported oils with the purpose of establishing the toxicity and the degree of penetration. (Primljeno u štampu 28. XI. 1958.) |