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Pojavom građevinarstva kao djelatnosti, ljudi počinju koristiti prirodne materijale poput kamena, drva, bambusa, opeke i slame za izgradnju svojih utočišta. Ovi materijali su prirodni, održivi i ne izazivaju štetne posljedice na okoliš. Međutim,dolaskom industrijske ere i povećanom potražnjom za građevinskim proizvodima, započela je masovna proizvodnja industrijskih materijala kako bi se ubrzala i optimizirala gradnja. Kao posljedica toga, građevinska industrija postala je jedan od najvećih zagađivača na svijetu. Cilj ovog rada je prikazati tradicionalne materijale i analizirati prednosti i nedostatke njihove upotrebe u građevinskoj industriji. Nadalje, u ovom radu istražuju se suvremene primjene tradicionalnih ekoloških materijala u arhitekturi, čime se pokazuje kako se suvremena arhitektura uspješno može kombinirati s tradicionalnim materijalima., Ever since construction began as an activity, people have turned to natural materials such as stone, wood, bamboo, brick, and straw to build their shelters. These materials are natural, sustainable, and do not cause harmful effects on the environment. However, with the onset of the industrial era and the increased demand for construction products, mass production of industrial materials began to accelerate and optimize construction. As a result, the construction industry has become one of the world's largest polluters. The aim of this paper is present traditional materials and to analyze the advantages and disadvantages of their use in construction industry. Furthermore, this paper explores contemporary use of traditional ecological materials in architecture, which shows how contemporary architecture can be successfully combined with traditional materials.

Cilj ovog rada je napraviti analizu trošenja alata kod finog glodanja kamena. Upotreba tvrdih metala za izradu reznih dijelova alata za obradu kamena u velikom je usponu. U sklopu ovog rada napravljeno je eksperimentalno ispitivanje kojem je cilj usporediti trošenje komercijalnog alata za fino glodanje kamena s oštricom od tvrdog metala s trošenjem alata čija je rezna oštrica napravljena od nanostrukturiranog tvdog metala. U prvom dijelu rada napravljen je pregled tehnologije obrade odvajanjem čestica glodanjem te pregled kamena kao materijala. Opisan je tvrdi metal kao materijal rezne oštrice alata te njegova nanostrukturirana inačica. Predstavljeni su i oblici trošenja alata te kako se postojanost rezne oštrice alata izražava u smjeru posmičnog gibanja. U drugom dijelu rada nalazi se opis eksperimentalnog dijela rada. Napravljena je CAM simulacija samog ispitivanja trošenja nakon kojeg je provedeno snimanje reznih oštrica alata industrijskom kamerom. Na temelju snimaka trošenja alata nakon ispitivanja donesen je zaključak o trošenju alata. Main objective of this paper is the tool wear analysis in fine stone milling. The usage of hard metal for making cutting parts of tools for fine milling of stone is in great rise. For this paper an experiment was made to compare wear of comercially avaliable tool for fine stone milling with hard metal cutting blade and cutting tool with cutting blade made of nanostructured hard metal. In the first part of the paper there is given a overview of fine milling technology and stone as a material. Hard metal and its nanostructured version are described as a material for cutting part of the tool. There is also given an overview of types of wear and formulas for durability of cutting edges. In the second part of the paper there is a CAM simulation of examination after which was provided inspection of cutting edge with industrial camera. At the end there is given a conclusion based on recordings of wear after inspection.

Polazište je ovog rada predstaviti razvoj kamenoklesarstva na otocima Braču i Korčuli. Naglasak je stavljen na povijesni kontinuitet od antike do danas, predstavljen kroz društvene, gospodarske i sociološke aspekte. Rad je podijeljen u tri dijela: prvi dio bavi se značajem kamena i kamenoklesarskog zanata u antici s naglaskom na kamenu materiju i alate koji su se tada koristili. U drugom dijelu rada opisan je nastavak kontinuiteta kroz nekoliko povijesnih razdoblja, od srednjeg vijeka, preko renesanse pa sve do dvadesetog stoljeća. U ovom dijelu naglasak je stavljen na kamenoklesarske obitelji i značajna imena naše povijesti umjetnosti kao produkta bogate tradicije. Osim značajnih imena dat je uvid u sličnosti i razlike bogatog kamenoklsarskog jezika Brača i Korčule. Posljednji dio rada opisuje situaciju kamenoklesarske tradicije danas te njezin prežitak kroz obrazovanje novih kamenoklesara, modernizaciju tehnologije obrade te njezinog utjecaja na kvalitetu finalnog proizvoda. Naposlijetku, predstavljen je pregled distribucije bračkog i korčulanskog kamena danas te mogućnosti prezentacije ovog plemenitog zanata u svrhu očuvanja tisućljetnog kontinuiteta., The starting point of this paper is to present the development of stone masonry on the islands Brač and Korčula. Emphasis is placed on historical continuity from antiquity to the present, presented through social, economic and sociological aspects. The work is divided into three parts: the first part deals with the importance of stone and stone-craftsmanship in antiquity with an emphasis on stone material and tools used at that time. The second part describes the continuation of continuity over several historical ages, from the Middle Ages, through the Renaissance until the twentieth century. In this section, emphasis is placed on stone-masonry families and significant names in our art history as a product of a rich tradition. In addition to significant names, an insight into the similarities and differences of the rich stone-carving language of Brač and Korčula is given. The last part of the paper describes the situation of the stone-carving tradition today and its survival through the education of new stone-carvers, the modernization of processing technology and its impact on the quality of the final product. Finally, an overview of the distribution of stone from islands Brač and Korčula is presented today and the possibility of presenting this noble craft in order to preserve its thousands years-old continuity.

Danas se najveći udio u postupcima obrade odvajanjem odnosi na obradu metala. U isto vrijeme, sve se više potiču istraživanja i razvoj tehnologije obrade nehomogenih materijala poput kamena i kompozita. Svojstva kod nehomogenih materijala nisu jednaka po cijelom volumenu promatranog dijela. Navedeni problem utječe na proces obrade te na samo trošenje alata. Na samom početku teorijskog dijela rada biti će objašnjen postupak izračuna snage, momenata i sila kod bušenja. Biti će prikazani mehanizmi i oblici trošenja alata koji se mogu pojaviti zbog različitih uvjeta u kojima se nalazi alat tijekom obrade. Opisat će se Taylor-ov model trošenja alata, zatim kako se definira postojanost oštrice alata, odnosno životni vijek alata i koji od modela se primjenjuje kod postupka bušenja. Objasnit će se koja je svrha sredstva za hlađenje, ispiranje i podmazivanje (SHIP) te koje sve vrste i načini dovođenja postoje. Na kraju teorijskog dijela biti će objašnjen postupak elektro-erozijske obrade žigom koji je potreban kod modifikacije komercijalnog svrdla za provedbu eksperimenta. U eksperimentalnom dijelu, objašnjen je postupak modifikacije komercijalnog svrdla s tvrdo lemljenom pločicom, na način da se kroz svrdlo izradi kanal koji omogućava ispuhivanje i hlađenje reznih oštrica svrdla tijekom procesa bušenja. Provodit će se bušenje različitih vrsta kamena s različitim parametrima obrade i stupnjem istrošenosti svrdla. Tijekom bušenja koristit će se komprimirani zrak za ispuhivanje i hlađenje reznih oštrica svrdla. Kod provođenja pokusa snimat će se signali sila rezanja i jakosti struja pogonskih motora te će se prema planu eksperimenta vršiti snimanje stražnje površine svrdla pomoću industrijske kamere. Na kraju će se usporediti dobiveni rezultati s rezultatima bušenja kamena bez upotrebe SHIP-a. Today, the largest share in machining processes refers to metalworking. At the same time, working technologies of non-homogeneous materials such as stone and composites are increasingly being explored. The properties of non-homogeneous materials are not equal through the entire volume of the observed body and that problem affects the working process and the tool wear. In the first part of this paper, the methods of calculation of powers, moments, and forces at drilling will be explained. The mechanisms and different types of tool wear that may occur due to the different cutting conditions in which the tool is located during cutting process will be displayed. Taylor’s model of tool wear and how the tool life is defined will be described. The purpose of cutting fluids (cooling lubrication fluid, coolant), which types and ways of bringing the coolant exist will be shown. At the end of first part, the Sinker Electrical Discharge Machining (Sinker EDM, Ram EDM) process, which is needed for modifying a commercial drill bit for experiment, will be explained. The experimental section of this paper explains the method of modifying a commercial drill bit with a hard solder plate, in such way that through the drill a channel is created which allows the flow of cutting fluids during drilling. Drilling of different types of stones will be carried out with different process parameters and the different degree of tool wear. Compressed air will be used during drilling to help extract a chip from the inside of the bore and cool the cutting edge of drill bit. During the experiment, the signals of cutting forces and the current of the drive motors will be recorded. Also, according to the plan of the experiment, the flank face of drill bit will be photographed using an industrial camera. At the end, the obtained results will be compared with the results of the same drilling processes carried out without using a compressed air as cutting fluid.

Kada se ispituje trošenje alata postoji niz modela trošenja koji se uglavnom primjenjuju kod obrade metalnih materijala, ali ima mali broj onih za procjenu trošenja nehomogenih materijala, kao što je primjerice kamen . U teorijskom dijelu ovog rada biti će prikazani osnovni uzroci i mehanizmi trošenja alata, kao i oblici trošenja alata koji se mogu pojaviti zbog različitih uvjeta u kojima se nalazi alat tijekom obrade. Opisat će se Taylor-ov model trošenja i prikazati utjecaj različitih parametara obrade na trošenje alata. Kako će se u eksperimentalnom dijelu obrađivati kamen, u teorijskom dijelu će još biti obrađen utjecaj različitih materijala na trošenje alata, koji se koriste za obradu kamena. Detaljno će biti opisani postupci trošenja takvih alata, odnosno uvid u strukturu alata i procese koji se zbivaju tijekom obrade. Praćenje istrošenosti alata je veoma važno zbog pravovremene i brze reakcije s kojom se čuva alat, a time i kvaliteta proizvoda. U eksperimentalnom dijelu provodit će se bušenje kamena te će se pratiti utjecaj istrošenosti alata na vrijednosti posmične sile te vrijednosti struja glavnog i posmičnog motora. Nakon bušenja određenog broj provrta oštrice, svrdla će se slikati te će se procijeniti stupanj istrošenosti i usporediti iznos trošenja s izbušenom duljinom, kao i promjena sila i struje glavnog motora u odnosu na istrošenost alata. In examination of tool wear there is a lot of models that concern tool wear at cutting metallic materials but little number of those which concern evaluation of wear when cutting heterogeneous materials, for example a stone. In first part of this paper there will be shown basic causes and mechanism of tool wear, and also different types of tool wear that can appear due to different cutting conditions during cutting process. Taylor model of tool wear and influence of different process parameters on tool will be described. Because stone material will be used in experimental part of this paper, an influence of different materials on tool wear, which are commonly used in stone machining, will be shown. Detailed view of tool wear and processes which happen during machining will be presented. Tool wear monitoring is very important due to timely and quick response which helps to save the quality of the product. In the experiment section a drilling of stone material will be conducted and force and current of main spindle and feed motor will be monitored. After certain number of drilled holes tool cutting edges, using special camera, will be photographed and they will be used to evaluate a degree of tool wear and compare it to overall drilling length, with comparison to respective changes of force applied on tool and main spindle motor current.

U ovom djelu prikazana je povijest zidanja u kamenu,odnosno način čovijekova staranja utom materijalu. S obzirom na geografski prostor kamen je najrelevantniji materijal za izgradnju u povijesti, pa se tako u ovom radu ukratko opisuje povijesne metode vađenja i obrade kamena. Opisuje se i proizvodnja vapna za mort koji je bio glavno vezivno sredstvo zidanih struktura. Opisuju se i neki povijesni izvori koji nešto govore o povezanoj tematici, ali i suvremena djela koja se odnose na tehnike zidanja poglaviti kamenom. U svakom razdoblju se opisuju tipovi zidanja te se pokušava opisati ponešto o načinu njihova nastanka ili barem svrsi. Počevši od najranijih zidova, pokušavaju se dokučiti veze i utjecaji sa mlađim načinima zidanja, naravno povezane sa novim metodama obrade kamena ili građevinskih tehnika koje dolaze protjecanjem vremena., This work presents the history of masonry in stone, ie the way the historic people created in this material. Given the geographical area, stone is the most relevant historic building material, so this paper briefly describes the historical methods of quarrying and processing stone. The production of lime for mortar, which was the main binder of masonry structures, is also described. There are also some historical sources that say something about related topics presented in this work, but also contemporary works related to the techniques of masonry, especially by stone. In each period, the types of masonry are described and an attempt is made to describe something about the way they were created or at least their purpose. Starting with the earliest walls, attempts are made to grasp the connections and influences with younger ways of historic masonry, of course associated with new methods of stone processing or construction techniques that come with the passage of time.

Maslina (Olea europea L.), zimzelena voćna vrsta, jedna je od vodećih uzgojnih vrsta Mediterana. Za kvalitetu i kvantitetu ploda, jedno od veoma bitnih agrotehničkih mjera je navodnjavanje. U ovom radu cilj je bio utvrditi utjecaj obroka navodnjavanja na morfologiju ploda i koštice masline. Istraživanje je obavljeno na Dugom otoku u mjestu Žman. Sorta koja se ispitivala je Coratina, a obavljano je u četiri tretmana i tri ponavljanja na 24 stabla masline. Plodovi za ispitivanje su uzimani sa srednjih rodnih grana i sa svakog stabla po 40 uzoraka. Mjerenja su se provedena na plodu i koštici, a mjerena je duljina, širina i masa ploda i koštice, te odnos duljina i širina ploda, odnos duljina i širina koštice, masa pulpe i udio pulpe. Obrada statističkih podataka je provedena u programima Excel i Statistica 11 uz korištenje Kruskal – Wallis jednosmjerne analize varijance u usporedbi mase, širine i duljine ploda i koštice, odnosa duljine i širine te udjela pulpe ploda i koštice. Rezultati istraživanja pokazuju kako je navodnjavanje utjecalo na porast svih morfoloških parametara ploda i koštice, te također pokazuje da postoje značajna odstupanja pri navodnjavanju različitim količinama vode. Kod plodova u kojima je navodnjavanje izostalo, oni su znatno zaostali u rastu i ta odstupanja su vidljiva i u izgledu ploda stvaranjem debele kutikule kako bi se plod zaštitio od daljnjeg gubljenja sokova. Olive (Olea europea L.), an evergreen fruit species, is one of the leading cultivated species in the Mediterranean. For fruit quality and quantity, one of the very important agrotechnical measures is an irrigation. In this paper, the aim was to determine the influence of irrigation rations on fruit and olive stone morphology. The research was conducted on Dugi otok in Žman. The tested olive variety was Coratina, and there were four treatments with three replications on 24 olive trees in total. The fruits for examination were taken from the middle fruiting branches and 40 samples from each tree. Measurements were performed on the fruit and stone, and the length, width and weight of the fruit and stone, as well as the ratio of length and width of the fruit, the ratio of length and width of the stone, pulp weight and pulp content were measured. Statistical data were processed in Excel and Statistica 11 using Kruskal - Wallis one-way analysis of variance in comparison of fruit and stone weight, width and length, length and width ratio and fruit and stone pulp content. The results of the research show that the irrigation affected the increase of all morphological parameters of the fruit and stone and shows that there were significant deviations in the irrigation with different amount of water. Fruits, in which irrigation was absent, were significantly smaller and these deviations were also visible in the appearance of the fruit by creating a thick cuticle to protect the fruit from further sap loss.

Veliki problem u očuvanju kulturnih dobara u urbanim sredinama je kontaminiranost istih grafitima. Za uspješno uklanjanje grafita potrebno je identificirati vrstu materijala i vrstu boje kojom je materijal kontaminiran te poznavati njihova kemijska i fizička svojstva kako bi potencijalnom metodom uklanjanja boje što manje utjecali na izvornost materijala. Rad je podijeljen u tri dijela. U prvom dijelu su opisana svojstva materijala koji su najčešće kontaminirani grafitima. Naglasak prilikom istraživanja je stavljen na kamen karbonatnog podrijetla jer je to najčešći materijal koji je kontaminiran grafitima u Dalmaciji, geografskom području na kojem je ovo istraživanje provedeno. Sve ove informacije su prikupljene u svrhu nastavka istraživanja koje se proširilo na pronalaženje informacija o međusobnom djelovanju materijala, boje korištene za izradu grafita te potencijalne metode za uklanjanje iste u svrhu pronalaska najučinkovitije metode za uklanjanje grafita. U drugom dijelu, na temelju istraživanja Photo-oxidative stability of paraloid acrylic protective polymers autora O. Chiantore, M. Lazzari u kojem je dokazano da kod interakcije UV zračenja i akrilne boje dolazi do raspada veza unutar molekule iste, napravljena je proba u kojoj su uzorci boje u spreju, koja je također na bazi akrila izloženi djelovanju UV zračenja pomoću UV lampe uz očekivanja da će se veze unutar molekule boje početi kidati te da će se boja moći lakše ukloniti. Uzorci su nakon djelovanja UV zračenja snimljeni pomoću FT-IR-a te je na snimkama vidljivo kidanje međumolekulskih veza i djelomično uklanjanje boje, no vremenski interval ove metode nije zadovoljavajuća. S obzirom na to da metoda čišćenja pomoću UV nije dala zadovoljavajuće rezultate u trećem dijelu napravljene su probe čišćenja kamena kontaminiranog grafitima koristeći dostupna komercijalna sredstva za uklanjanje premaza u kombinaciji s već poznatim metodama čišćenja. Većina probi je napravljena na kamenu lokalnog podrijetla, a napravljene su i probe na žbuci koja je također materijal često izložen grafitima. Dobivene rezultate bi mogli primjenjivati stručnjaci kako bi skratili vrijeme kod odabiranja prikladnog sredstva, načina njegovog nanošenja, vremenskog intervala djelovanja, načina čišćenja te u odabiru prema financijskoj pristupačnosti. Ovakvo rješenje bi smanjilo rizik od oštećenja samog materijala jer korištena komercijalna sredstva djeluju samo na sloj boje ali ne i na sam materijal te njegovu patinu što je bio slučaj kod dosadašnjihmetoda kao što je pjeskarenje. Također smanjili bi se troškovi procesa uklanjanja grafita koji su za sada dosta veliki zbog metoda koje iziskuju korištenje raznih strojeva i njihov transport. A major problem in the preservation of cultural assets in urban areas is the contamination of the same with graffiti. For successful graffiti removal is necessary to identify the type of material and the type of paint with which the material is contaminated and know their chemical and physical properties in order to minimize the impact on the originality of the material with a potential paint removal method. The paper is divided into three parts. The first part describes the properties of materials that are most often contaminated with graffiti. The emphasis in the research has been placed on the stone of carbonate origin because it is the most common material contaminated with graffiti in Dalmatia, the geographical area in which this research was conducted. All this information has been collected for the purpose of continuing research that expanded to find information about the interaction of materials, paints used to make graffiti and potential methods for removing the same for the purpose of finding the most effective method for removing graffiti. In the second part, based on the research Photo-oxidative stability of paraloid acrylic protective polymers by O. Chiantore, M. Lazzari, in which it was proven that the interaction of UV radiation and acrylic paint breaks the bonds within the molecule, a test has been made in which the spray paint samples, which is also acrylic-based, have been exposed to UV radiation using a UV lamp with the expectation that the bonds within the paint molecule will begin to break and that the paint will be easier to remove. The samples have been taken by FT-IR after the action of UV radiation, and the images show the breaking of intermolecular bonds and partial removal of color, but the time interval of this method is not satisfactory. Since the UV cleaning method did not give satisfactory results in the third part, tests have been made to clean the graffiti-contaminated stone using available commercial coating removers in combination with already known cleaning methods. Most of the tests have been made on stone of local origin, and the tests have also been made on plaster which is also a material often exposed to graffiti. The obtained results could be applied by experts in order to shorten the time when choosing a suitable agent, the method of its application, the time interval of action, the method of cleaning and in the selection according to financial affordability. Such a solution would reduce the risk of damage to the material itself, because used commercial agents act only on the paint layer, but not on the material itself and its patina, which has been the case with previous methods suchas sandblasting. It would also reduce the cost of the graffiti removal process which is quite high for now due to the methods that require the use of various machines and their transport.

Maslina (Olea europaea L) je gospodarski značajna voćna vrsta Mediterana i mediteranskog dijela Republike Hrvatske. Navodnjavanje masline je neizostavna agrotehnička mjera kojom održavamo prinos i ekonomsku isplativost proizvodnje maslinovog ulja. Cilj rada je utvrditi kako različita količina obroka vode kod navodnjavanja utječe na morfološke karakteristike ploda i koštice. Istraživanje je provedeno na Dugom otoku u mjestu Žman. Poljski pokus je bio postavljen na sorti coratina, na 24 stabla masline, u četiri varijante s tri ponavljanja. Za morfološka mjerenja plodovi su bili uzorkovani sa srednjeg dijela rodne grane, a uzorak je činilo 40 plodova. Od morfoloških karakteristika ploda i koštice mjereni su: masa ploda, duljina ploda, širina ploda, odnos duljine i širine ploda, udio pulpe ploda, masa pulpe ploda, udio pulpe ploda, masa koštice, duljina koštice, širina koštice i odnos duljine i širine koštice. Statistička obrada podataka je provedena programom SigmaPlot11 te je za usporedbu mase, širine, duljine, odnosa duljine i širine te udjela pulpe ploda i koštice korištena je Kruskal – Wallis jednosmjerna analiza varijance. Rezultati istraživanja su utvrdili da povećanje količina vode za navodnjavanje nije utjecala na povećavanje: duljine ploda, odnosa između duljine i širine ploda, masu koštice, širinu koštice, duljinu koštice, odnos duljine i širine koštice i na indeks zrelosti ploda. Međutim, povećana količina vode utjecala je značajno na povećavanje: mase ploda, širine ploda, mase pulpe ploda te udjela pulpe u plodu. Dobiveni rezultati su u skladu s literaturnim podacima i rezultatima iz prijašnjih istraživanja, osim indeksa zrelosti. Olive tree (Olea europaea L) is an economically significant fruit species of the Mediterranean and the mediterranean area of the Croatia. The irrigation of olive trees is an indispensable agrotechnical intervention by which we maintain the yield and economic effectiveness of olive oil production. The aim of the paper was to determine how different amounts of water during irrigation affect morphological characteristics fruit and pits. The research was conducted on island Dugi otok in the place Žman. The field experiment set on the coratina variety, on 24 olive trees, in four variants with three replicates. For morphological measurements the fruits were sampled from the middle part of the fruiting branch, while in the sample was 40 fruits. From the morphological characteristics of the fruit and stone were measured: fruit weight, fruit length, fruit width, ratio of fruit length and width, fruit pulp content, fruit pulp mass, stone mass, stone length, stone width, and ratio of stone length and width. Statistical data was performed by SigmaPlot11 programme and for comparison of mass, width, length, ratio of length and width and content of fruit pulp and stone Kruskal - Wallis one-way analysis of variance was used. The results of the study obtained that the increases in volume of water for irrigation did not affect the increase of: fruit length, ratio of fruit length and width, stone mass, stone width, stone length, ratio of stone length and width and maturity index. However, the increased amount of water had a significant effect on the increase of: fruit weight, fruit width, fruit pulp weight and fruit pulp content. The results obtained are in agreement with literature data and results from previous researches, except for the maturity index.

U radu se obrađuje uporaba mramora u Rimskom Carstvu. Na početku se prikazuju tema, ciljevi i povijest istraživanja. Potom se donosi kronologija privatne i javne uporabe mramora od najranijih vremena do rimskog carskog razdoblja. Opisuju se najzastupljenije vrste bijelog i raznobojnih mramora u Italiji i provincijama. Sažimaju se podaci o vađenju kamena i njegovu dopremanju na odredište. Na primjeru sarkofaga ocrtava se zastupljenost pojedinih vrsta bijelog mramora. Na koncu se skiciraju vijesti o mogućim cijenama mramora., Archaeological, epigraphic, and literary evidence attests to the use of marble in antiquity. Different approaches have been used to address the importance of marble in the Roman imperial period. This paper aims to provide a general outline of the types, quarrying, distribution, and costs of marble during the 1st and 2nd centuries CE. The main conclusions can briefly be summarized as follows. The use of marble is deeply rooted within the Classical and Hellenistic tradition. Initially used in the private sphere (some writers raised objections to its excessive use), marble has become an important part of major public works in the Augustan era and enjoyed a wide distribution in the early imperial period. Different types of marble have been abundantly attested in the form of wall and pavement slabs, columns, pillars, statues, furniture, and funerary monuments. These objects not only indicate the high social position of their owners, but also illustrate technological and artistic changes of the imperial era. Ancient marble, granite, and limestone quarries provide useful information about the process of stone extraction and shed some light on the methods of the quarries management. The Roman shipwrecks testify to ancient maritime trade routes used for the commercial transport of marble cargo. Judging from epigraphical and archaeological evidence, the stone cutters and marble merchants expanded their activities from the Eastern Mediterranean by the end of the 1st century CE. Important stylistic features are particularly discernible on elaborate marble sarcophagi. Produced in Attica and Prokonessos, they were frequently exported westwards as half-finished products, but were also fabricated in Italy (Ostia). Approximate calculations of the price of white and colored marble are mainly based on epigraphic evidence from the late antiquity.

U članku se donosi klasifikacija kamenih artefakta sa zaštitnih arheoloških istraživanja na gradilištu plinovoda u Ulici Stjepana Radića u Solinu. Autor detektira uzorke uspoređujući ih s referentnim uzorcima iz baze podataka Odsjeka konzervacije i restauracije kamena Umjetničke akademije u Splitu. Određuje naziv kamena, vrstu i kamenolome., The paper presents classification of stone artefacts from the archaeological rescue excavations made at the gas pipeline laying site in the Stjepana Radića street in Solin. The author identifies samples by comparing them with the referral samples in the database of the Stone Conservation and Restoration Department of the Arts Academy in Split. Determined are rock names, types and quarries.

Rad „Prijedlog osuvremenjivanja muzeološke prezentacije korčulanskog kamenoklesarstva“ se sastoji od tri dijela. U prvom dijelu upoznajemo se s otokom i gradom Korčulom, s naglaskom na palaču Gabriellis i osnutak Muzeja grada Korčule. Drugi dio sadrži detaljniji opis muzejske zbirke popraćen s fotografskim prikazima sadržaja zbirke kamenoklesarstva u palači Gabriellis, te tri prijedloga osuvremenjavanja postava odjela kamenoklesarstva u muzeju. Na posljetku u trećem dijelu, koji je ujedno zauzima i najveći dio ovog rada, nalaze se podatci o povijesti kamenarstva i kamenoklesarstva od samih kamenoloma, alata i sprava korištenih u eksploataciji kamena na području Korčule, povijesti samog zanata i trgovine, kao i školovanja, do niza poznatih stranih i domaćih obrtnika i umjetnika koji su djelovali stoljećima sve do danas., The paper "Proposal for the Modernization of the Museological Presentation of Korčula Stonemasonry" consists of three parts. In the first part, we are introduced to the island and the town of Korčula, with the emphasis on the Gabriellis Palace and the founding of the Korčula City Museum. The second part brings a more detailed description of the museum collection, accompanied by photographic displays of the contents of the stone-carving collection at the Gabriellis Palace and three proposals of modernization of the museum's stone-carving department. Finally, the third part, which also occupies most of this work, contains information on the history of masonry and stone masonry from the quarries, tools and devices used in the exploitation of stone in the area of Korčula, the history of the craft and trade itself, as well as education, to a number of well-known foreign and local craftsmen and artists who have worked for centuries and continue to do so to this very day.

Kamen je jedan od prirodnih materijala koji se svakodnevno koristio od najranijih početaka čovječanstva. Danas se koristi kao građevni materijal, a u većini drugih slučajeva ima dekorativnu i zaštitnu zadaću. Kao i kod drugih materijala, kombinacija mehaničkih, fizičkih, kemijskih svojstava uvjetuju mogućnost obrade i uporabe kamena. Nemoguće je, zbog njegove heterogene strukture, odrediti točne vrijednosti parametara kojim bi proces obrade bio najučikovitiji. Tako npr. svrdlo pri bušenju nailazi na nekoliko različitih struktura kamena koje se međusobno razlikuju po svojstvima, posebno tvrdoći i bušivosti. Bušivost ukazuje na lako ili otežano prodiranje svrdla u materijal pa dobra procjena bušivosti rezultira dobrom procjenom tvrdoće obrađivanog materijala. U procesu obrade materijala odvajanjem čestica, rezni dio alata se troši. S obzirom na to, svrdlo je za vrijeme rada podvrgnuto mehaničkim, toplinskim i kemijskim opterećenjima koja uzrokuju promjenu geometrijskog oblika oštrice tj. njezinu istrošenost. Što veći stupanj automatizacije procesa i predviđeni otpis alata ima svoje prednosti kao što su: smanjenje vremena potrebnog za zamjenu alata i izbjegavanja mogućih oštećenja stroja pri istrošenju alata, što je ujedno i pozitivno s ekonomske strane. Praćenjem stupnja istrošenosti, moguće je isplanirati proces s optimalnom potrošnjom energije, maksimalnim životnim vijekom alata i najvećom produktivnošću te učinkovitošću. U radu je opisan utjecaj tvrdoće kamena na učinkovitost procesa bušenja i trošenje oštrice svrdla. Cilj pokusa je bio analizirati signale sila rezanja i jakosti struja pogonskih motora te procijeniti utjecaj tvrdoće na učinkovitost procesa. Uzorci kamena veće ili manje tvrdoće, podvrgnuti su ciklusima trošenja i mjerenja, kako bi se na kraju iz mjerenih vrijednosti tvrdoće procijenilo njihovo međudjelovanje. Stone is one of the natural materials that are being used from the earliest beginnings of humanity. Today it is used as a building material, and in many cases stone has a decorative and protective role. As it is with other materials, a combination of mechanical, physical and chemical properties condition the ability of stone to process and use. It is impossible, because of its heterogeneous structure, to determine the correct parameters which make the process of treatment stone most effective. For example, the drill when drilling encounters several stone structures that differ in properties, especially hardness and drillability. Drillability indicates easy or difficult penetration of the drill into the material and a good estimation of drillability results in a good estimation of the materials hardness. When processing materials, the cutting part of the tool is being spent. Given that, the drill during operation is subjected to mechanical, thermal and chemical loads that may change the geometry of the blades. A higher degree of process automation and provided tool life has its advantages, suchas reducing the time required for tool change and to avoid possible machine damage caused by the tool wear. That is also positive from the economic point of wiew. By monitoring the degree of tool wear, it is possible to schedule a process with optimal power consumption, maximum tool life and highest productivity and efficiency. This paper describes the influence of rock hardness on the efficiency of the drilling process and tool wear. The aim of the experiment was to analyze signals of cutting forces and motor drive current and evaluate the impact of hardness on the process effectiveness. Samples of stone with different values of hardness were subjected to wear and measurement cycles. In the end, the measured values of hardness were taken into account to evaluate their interaction.

U radu su opisani postupci i prikazani rezultati ispitivanja najvažnijih mehaničkih svojstava gradiva građevina zidanih od opeka i kamena. Ispitivane su posmične, tlačne i vlačne čvrstoće morta, opeke i kamena te moduli elastičnosti i Poissonovi koeficijenti morta i kamena. Najveći dio ispitivanja proveden je na građevinama koje su zaštićeni spomenici kulture u Vukovaru i Dubrovniku. Istaknuta je važnost tih ispitivanja za izradu kvalitetnoga projekta sanacija zidanih građevina., Procedures and results obtained by testing principal mechanical properties of materials for masonry buildings made of brick and stone, are presented in the paper. The testing includes determination of shear strength, compressive strength and tensile strength for mortar, brick and stone, as well as determination of the modulus of elasticity and Poisson's ratio for mortar and stone. Most of these investigations were conducted on structures categorized as protected cultural monuments, in the cities of Vukovar and Dubrovnik. The significance of these analyses for the preparation of appropriate rehabilitation design documents for masonry buildings is emphasized.