Mechanical and Durability Properties of Mortar With the Addition of Pwc Sawdust

Proizvodnja betona u posljednjih 30-tak godine je u drastičnom porastu što dovodi do prekomjerne upotrebe prirodnih sirovina. Sukladno tome raste potražnja za zamjenskim materijalom. Dok s druge strane, velike količine otpadnog materijala koji nastaje kao nusprodukt različitih grana industrije, čije je zbrinjavanje upitno, uvelike doprinosi u onečišćenju i lošoj održivosti okoliša naročito u današnje vrijeme. Uzimajući sve navedeno u obzir, osnovna ideja ovog rada je reciklaža PVC piljevine, industrijskog nusprodukta prilikom izrade PVC stolarije, u obliku sirovine za proizvodnju morta, odnosno betona. Ovim radom određuje se utjecaj PVC piljevine na osnovna svojstva svježeg i očvrslog cementnog morta. U eksperimentalnom dijelu rada izrađene su vlastite mješavine cementnog morta pri čemu se određeni postotak volumena pijeska zamijenio s PVC piljevinom u količini od 0%, 5% i 10%. Ispitana su svojstva svježeg morta te mehanička i trajnosna svojstva očvrslog morta. Dodavanjem aditiva uklanjaju se problemi obradivosti svježeg morta uočeni u prethodnim ispitivanjima. Rezultati ispitivanja očvrslog morta pokazuju trend smanjenje tlačne čvrstoće i čvrstoće na savijanje povećanjem udjela PVC piljevine u odnosu na referentnu mješavinu. Međutim, ispitivanjem kapilarne vodoupojnosti i otpornosti na habanje postižu se poboljšana svojstva kod mješavina s prisustvom PVC piljevine nego kod referentne mješavine. Provedbom ispitivanja uočeno je da PVC poboljšava i duktilnost uzoraka. Zaključuje se da je mort, s određenim postotkom zamjene volumenom pijeska s PVC piljevinom uz dodatak određene količine aditiva radi postizanja zadovoljavajuće obradivosti, moguće primijeniti u praksi. U slučaju potrebe za poboljšanjem mehaničkih svojstava koja su degradirana dodavanjem PVC piljevine kao i nepropusnosti i trajnosti, preporuča se dodavanje pucolanskog materijala npr. metakaolina što je i dokazano u ovom diplomskom radu.The production of concrete in the last thirty years show a constant increase which brings to overuse of natural resources. The demand for substitute materials is therefore increasing accordingly. On the other end, great amounts of waste material which is produced as a byproduct of different types of industries, and is by itself hard to dispose, brings greatly to the pollution and lack of sustainability of the environment at the moment. Taking everything mentioned into account, the original idea of this thesis is recycling of PVC sawdust, industrial byproduct of the production of PVC carpentry, in the form of a raw material in the production of mortar and concrete. The main focus of this thesis is to determin the influence of PVC sawdust on the basic properties of fresh and hardened cement mortar. In the experimental part of this thesis several mixtures of cement mortar were made in which different volume percentages of sand were replaced with PVC sawdust from 0%, 5% and 10% respectively. The properties of fresh mortar were tested, as well as the mechanical and durability properties of hardened mortar. The use of additives solved problem with the workability of fresh mortar that was noticed in earlier experimental investigation. The experimental results of hardened cement mortar show a decreasing trend on compressive and flexural strength with the increase of PVC sawdust in comparison to the reference mixture. However, test results from capillary water absorption and wear resistance show improved properties in the mixture with PVC sawdust compared to the reference mixture. With further testing, it was noticed that PVC improves the ductility of the samples as well. It can be concluded that mortar, with the optimal sand replacement with PVC sawdust, and the use additives for better workability, can be applied in practice. In case if it is necessary to improve the mechanical properties, which are decresed by adding PVC sawdust, as well as the impermeability and durability, it is recommended to add pozzolanic material e.g. metakaolin which has been proven in this thesis