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Since lime renders have slow development of strength, especially in conditions of increased humidity, different types of additions were often used trough history, in order to improve their resistance and durability. This paper presents the effects of locally produced fine crushed tile aggregate addition on physical and mechanical properties of lime-based coating, representing final outer layer of traditional renders, both in normal and increased humidity conditions. This aggregate has been used as partial replacement of natural river aggregate, with granulation 0/0,5 mm in amount of 25, 50, 75 and 100% by volume. Flexural and compressive strength, capillary water absorption, ultrasonic pulse velocity, dynamic modulus of elasticity and open porosity were tested on prismatic samples at the ages of 14, 28 and 60 days. Results show the positive effects of crushed ceramic addition at all ages, especially for the samples cured in humid conditions.

Malteri na bazi kreča korišćeni su prilikom zidanja i malterisanja velikog broja istorijskih objekata od 6000. godina pre nove ere, pa sve do kraja XIX veka. Otkriće hidaruličkih veziva u XIX veku omogućilo je proizvodnju novih maltera viših mehaničkih karakteristika sa većom brzinom očvršćavanja. Tokom prve polovine XX veka ovi malteri su u potpunosti zamenili krečne maltere, pa su primenjivani i prilikom izvođenja sanacija na istorijskim objektima. Usled razlika u mehaničkim karakteristikama, vodopropustljivosti i paropropustljivosti primena maltera na bazi cementa dovela je do oštećenja postojećih materijala. Iz tog razloga se u drugoj polovini XX veka prvi put uvodi pojam kompatibilnosti postojećih materijala i materijala koji se koriste prilikom sanacija i restauracija istorijskih objekata. Aktuelna istraživanja kreću se u pravcu detaljnih ispitivanja uzoraka maltera uzetih sa objekata od interesa kao i u definisanju receptura i ispitivanju svojstava novih maltera koji bi mogli biti korišćeni prilikom restaruacija istorijskih objekata. U radu je dat pregled objavljenih rezultata ispitivanja iz obe navedene oblasti. Opisan je i uticaj pojedinačnih komponentnih materijala na svojstva krečnih maltera.

The civil engineering materials in the whole existing civilization have many characteristics which do not depend of past historical period, but, there is forever and everywhere fractal characteristic of structures morphology. Many archeological sources which are very rich with samples from prehistorical periods, ancient Greece, Roman and Vestian period, Slovenes and later, are existing in Balkan and South-East Europe. These sources and samples are very important for our civilization evaluation. Sometimes or even often, we fined archeological samples which are fractured and damaged. In such situation, it is very important to reconstruct some of these parts. We developed quite new method based on fractals analysis and characterization which is an excellent tool for reconstruction the archeological and heritage samples. In these paper, we successfully presented this application and opened new perspectives for research in this area.

The paper presents a comparative analysis of mortars found at two significant archeological sites in Serbia. Specifically, those are Gamzigrad (Romuliana) near Zajecar and the archeological site Caricin Grad near Leskovac. In the previous papers, we dealst with the characterization of mortars from both sites. It was the first examination of mortars from both locations. The comparative analysis of mortars was performed based on the data obtained by testing physical-mechanical properties such as: water absorption, porosity, gravity and specific mass. Mineralogical composition (both quantitative and qualitative) was obtained based on XRD / XRF and SEM/EDS analyses. The comparative analyses of the mortar obtained from the mentioned archeological sites indicated that mortars from both locations contained grains of river aggregate, crushed limestone aggregate and crushed masonry bricks. The share percentage varied. Regarding the binder, the mortar from the Gamzigrad (Romuliana) site had limestone used for the binder, while the mortar from the Caricin Grad site had clay and powdered masonry bricks. The obtained results of mortar analysis pave the way for further research with an aim of making repair mortars.

The aim of this study was mineralogical and chemical analysis of mortar from the floor, ceiling and wall of Stibadium B, from the archaeological site of Mediana. ICP-OES and FTIR-spectroscopy were used to determine chemical composition and some major mineralogical species. The obtained results show that lime mortar is probably used. Large contribution of silicon- and aluminum-oxides, indicate the presence of quartz and clay minerals derived from the aggregate, river sand and crushed bricks. The obtained results also show large amount of iron, manganese and copper. The determinated metals in samples from floor and wall of Stibadium B, are mostly present in oxide fraction, while in sample from ceiling, they are mostly found in silicate fraction. V Serbian Ceramic Society Conference - Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts; September 21-23, 2016; Belgrade

Felix Romuliana is a palace erected during the rain and after the design of the Emperor Gaius Valerius Galerius Maximianus. It belongs to the category of monuments of Roman court architecture which is associated with the time of Tetrarchy. During the archeological excavations, two fortification systems were discovered, they younger outer system with twenty polygonal massive towers, and an older inner system with sixteen towers of quadragonal and octagonal towers flanking the gates. The younger outer fortification is polygonal. The communication east-west connecting two gates divides interior space into two entities. Systemic archeological research last since 1953 by probing the northwest part of the inner space. Conservation works run simultaneously with the excavations. Mortar samples were taken from the towers XI and XII of the old fortification, as well as from the tower 15 and the part of the rampart between towers 1 and 3 of the younger fortification. Mortars were analyzed with the goal of obtaining information about morphological, mineralogical, chemical and basic physical properties of mortar. For analysis of these properties, optical microscopy and scanning electronic microscope were used. Depending on the location sampled mortars, there are differences of individual properties of mortar. The optical examination of macroscopic appearance of mortar samples indicated that those are limestone binder mortars. Aggregae grains are both river and stone aggregate. Mortar porsity differs depending on the location where samples were taken.

The paper presents research of mortar from the archeological site Caričin Grad. Caričin Grad is an early Byzantine site located near Leskovac, Serbia. It is of extreme importance for the study of early Medieval architecture. The town covers the area of around 7 ha. In town planning terms, it consists of Acropolis, Middle, and Lower tow, each with its system of ramparts and the structures leaning on them. There is a large number of sacred buildings, Baths, public and private buildings, well developed water supply and sewerage system provide evidence of the town’s importance. Mortar was sampled from the buildings surrounding the circular square of the Middle town, from the structures north of Acropolis, gate between the Middle and Lower town, east gate of the Lower city as well as the aqueduct structure. Mortars were analyzed with the goal of obtaining information about morphological, mineralogical, chemical and basic physical properties of mortar. For analysis of these properties, optical microscopy was used and scanning electronic microscope. Depending on the location sampled mortars, there are differences of individual properties of mortar. The optical examination of macroscopic appearance of mortar samples indicated that those are limestone mortars. The aggregate grains detected are river and crushed limestone aggregate and fine pieces of bricks.

Application of recycled rubber and recycled glass in replacement of a portion of aggregate has been present in practice and it is the subject of research in many laboratories worldwide. In this paper is presented a part of experimental research whose goal was to determine the effects these recycled materials have on changing the properties of fresh and hardened concrete. In the course of experimental work, a special attention was paid to the study of the effects the usage of recycled glass and recycled rubber has on the variation of ultrasound wave velocity in concrete, which is correlated with the compressive strength of concrete. It was found the increase of added recycled rubber has significant effects on reduction of ultrasound wave propagation through concrete. In case of addition of 30% of recycled rubber, this decrease amounts to even around 18.5%. The addition of recycled glass has considerably smaller effect on the reduction of ultrasonic velocity of around 4%.

This dissertation is focused on the development of methods for the damage detection and localization in concrete structures. This research is an attempt to meet the requirements of monitoring and non-destructive testing and assessment (NDI / P) of structures, as well as to reduce the current shortcoming in methods for monitoring the condition of concrete structures. The research gives numerical procedures for modeling the damage detection in linear reinforced concrete (RC) elements, starting from the model of piezoelectric smart aggregates (PZT PA) and further to the models of wave propagation. Verification of numerical models based on experimentally obtained results was performed, as well as parametric analysis of the change in RMSD (root mean square deviations) of the damage index in relation to individual parameters. For plate concrete elements, detection was performed using the existing two-dimensional damage index based on numerical simulations. For the damage localization, a hybrid method based on energy approach, time of propagation of the incoming wave from the actuator to the sensor as well as discrete wavelet signal transformation has been developed. A hybrid approach has been developed for the general shape of the concrete element, arbitrary number and position of PZT actuators / sensors, and arbitrary shape and position of damage. The mentioned hybrid approach was verified through experimental and numerical research on models with one and two damaged points. For 3D damage detection in concrete structres, a three-dimensional (3D) damage index based on a one-dimensional (1D) RMSD damage index has been developed. The 3D damage index was calculated for different damage cases, based on the results obtained by numerical simulations. A hybrid method developed for plate elements has been extended to 3D damage localization. A hybrid method for spatial damage localization was verified on parallelepiped samples/models by comparing experimental and numerical results. The obtained results indicate that the methods for damage detection and localization are very efficient for linear and plate concrete elements, while in the case of 3D concrete structures, further elaboration of the presented method is necessary. All methods presented in the doctoral dissertation have been numerically tested and some have been experimentally verified. The main aim of the development of the aforementioned methods for the damage detection and localization is to enable the use of PZT actuators/sensors for structural health monitoring of concrete structures over time.

During the exploitation period, the properties of reinforced concrete in structures constantly decrease, resulting in damage that directly affects serviceability of the structures. Initiation and development of damage are time-dependent phenomena accompanied by deteriorating processes, which are differently implied depending on the environment. The influence of environment is an important factor that determines type of damage and mode of propagation, and damage level depands on the exposure of structures elementsto aggresive action.

Током XX века сазнања о своjствима, начинима справљања и могућностима примене кречних малтера су у великоj мери изгубљена. Ипак, током последњих тридесетак година, ови материjали се користе у санациjама и рестаурациjама историjских обjеката, како због компатибилности са постоjећим материjалима коришћеним за зидање и облагање, тако и због повољних физичко-механичких своjстава. За потребе ове дисертациjе изабрани су локално доступни компонентни материjали, у циљу справљања малтера компатибилних са кречним малтерима за малтерисање, коришћеним на простору Србиjе до средине XIX века. У свим малтерима испитиваним у склопу експерименталног рада као везиво jе коришћено кречно тесто одлежало 6 месеци и речни песак "дунавац", у две различите фракциjе: крупниjи (0/4 mm) и ситниjи (0/0,5 mm). У првом делу експеримента испитиване су две групе малтера: малтери у коjима jе креч делимично замењен природним зеолитом и малтери у коjима jе речни песак делимично или потпуно замењен дробљеном опеком. Ове врсте малтера справљане су за два односа креча и агрегата, 1:3 и 1:1 (запремински), коришћењем два начина неге. На укупно 19 мешавина су вршена испитивања у свежем и очврслом стању при различитим старостима (пре свега хидрофизичка, микроструктурна и механичка своjства). У другом делу експеримента на одабраним малтерима са додатком зеолита, нанетим на подлогу од природног камена, користећи иновативну методу припреме узорака, извршена су испитивања траjности (отпорности на деjство мраза и отпорности на деjство растворљивих соли). Показано jе да оба коришћена додатка, када су малтери неговани у влажноj средини, утичу на повећање чврстоће при притиску, укупне порозности и коефициjента капиларног упиjања и доводе до промена у микроструктури кречних малтера. Показано jе да jе предложени начин формирања композитних узорака адекватан за извођење испитивања траjности ових материjала. In the course of XX century, the knowledge on the properties, preparation methods and the possibilities for the application of lime mortars has been lost to a large degree. However, during the last three decades these materials have been used in the reparations and restorations of historical buildings, both for their compatibility with the existing mortars used for building and rendering, and for their favorable physico-mechanical properties. Locally available component materials were chosen for the purposes of this dissertation, with the aim of preparing the mortars compatible with lime mortars that were used for rendering on the territory of Serbia until the first half of XIX century. The lime putty, aged for six months, and river sand “Dunavac” were used as binders in two different fractions: with larger grains (0/4 mm) and with smaller grains (0-0,5 mm) in all the investigated mortars examined within the experimental part of work. In the first part of the experiment were investigated two groups of mortars: the mortars in which the lime was partially replaced with natural zeolite and the mortars in which the river sand was partially or completely replaced with crushed brick. These mortar types were prepared for two lime/aggregate ratios, 1:3 and 1:1 (volume), using two types of care. Investigations were performed on 19 mixtures in total, in fresh and hardened states, at different ages (mainly hydrophysical, microstructural and mechanical properties). In the second part of the experiment durability tests (resistance to the effects of frost and soluble salts) were performed. It has been shown that both additions that were used, when the mortars were cured in the humid environment, affected the strength increase with the pressure increase, total porosity and the coefficient of capilary absorption. Both additions induced changes in the lime mortars microstructure. It was concluded that the suggested method of preparation of composite samples was adequate for performance of investigations of the durability of these materials.

The connection between eco and building materials can be successfully accomplished by using geopolymers. Geopolymers are composite materials made of long chain molecules incurred by polymerization of geopolymer binders. Usually, geopolymers are defined as a solid and stabile aluminosilicate materials, made of industrial byproducts and liquid solutions such as NaOH and Na2SiO2. …The experimental part of the dissertation, contains the results of physical-mechanical, microscopic and durability properties of geopolymer mortars and concrete based on fly ash. For the purpose of determining the effect of different byproducts on characteristics of geopolymer mixtures, 24 batches of mortar and 8 batches of concrete were made and tested. Mass percentages of ladle slag, wood ash, red mud and waste glass in respect to the total mass of the binder was 0 to 20%, varied in 5 % steps of replacement. Mass percentage of ground granulated blast furnace slag in respect to the total mass of the binder was 0 to 100%, varied in steps of 20 % steps of replacement. All batches were made by using binder with the particle size smaller than 0,09 mm. The samples of geopolymer mortar and concrete were cured at an ambient temperature. …According to the test results some recommendations for the possible application of fly ash and other industrial byproducts for making geopolymer mortars and concretes are made. It has been proved that geopolymer mortars and concretes might be used as a construction building materials. Furthermore, because of their physical-mechanical characteristics and durability properties, they can be alternative solution for the traditional mortar and concrete mixtures.

Timber-concrete composite structures represent a composite system that is formed by coupling of timber and concrete elements using different types of connectors. They are applied in the rehabilitation and construction of new facilities. In order to enable their wider application, it is necessary to ensure the general availability of relevant technical regulations in relation to their design and construction. The main goal of the doctoral dissertation is to contribute to the improvement of the design process of timber-concrete composite structures and their maintenance during the service life. Thus, certain multi-parametric probabilistic analyzes and optimizations should be carried out which would result in certain recommendations that would have practical application in the certain conditions of design, construction and maintenance of these composite systems. In order to determine the most important design parameters, a stochastic sensitivity analysis of the maximum equivalent stress and maximum deflection of the timber-concrete composite beam was performed. A multiobjective optimization was also conducted in order to choose an optimal solution for the dimensions of the observed composite beam. A new probabilistic deterioration model has been developed that describes the true nature of the behavior of the timber-concrete composite system due to the long-term load.

Adhesive joints offer many advantages compared to the traditional joining techniques in metallic structures. However, the lack of unified design standards and procedures limit their wider use in civil engineering industry. For the purpose of standardization, extensive experimental work has to be done on investigating their behavior under the service conditions. Besides the influence of the joint geometry, the manufacturing process and the temperature and humidity effects, type of the loading has the greatest influence on the behavior of adhesive joints. Main goal of this dissertation was to investigate behavior of adhesive joints in metallic structures under static and cyclic loading, using modern experimental and numerical methods. In order to achieve this the selection of proper adherent surface preparation procedure was necessary. Experimental investigation of the behavior of adhesive joints subjected to static and cyclic loading was conducted on two types of adhesive joints: galvanized steel façade joint and double lap shear joint. Based on the results of the experimental investigation, as well as the results from the literature, new models and methods were developed for modeling of the behavior and predicting the fatigue life of adhesive joints subjected to static and cyclic loading.

U disertaciji su prikazani rezultati sopstvenog eksperimentalnogistraživanja sulfatne otpornosti betona sa recikliranim agregatom.Istraživanje je zasnovano na komparativnoj analizi dve grupe betona kojese razlikuju u krupnom agregatu, a u okviru kojih su varirani dve vrstecementa i dva vodocementna faktora. Sulfatna otpornost je proveravananakon 3 i 6 meseci boravka u 5% Na2SO4 i u 5% MgSO4. Na očvrslom betonuispitivani su kapilarno upijanje vode, promena dužine uzoraka, čvrstoćapri pritisku i urađene su mikrostrukturne analize: MIP, SEM, BSE/EDS,XRD i FTIR. Istaknuto je da se primenom krupnog agregata od recikliranogbetona i veziva odgovarajućeg mineraloškog sastava mogu dobitikonstrukcijski betoni, odnosno betoni sa zadovoljavajućim mehaničkimkarakteristikama, ali i sa zadovoljavajućom trajnošću sa aspektasulfatne korozije., This paper presents the experimental research results of the sulphate resistance ofconcrete with recycled aggregate. The research is based on a comparative analysis oftwo groups of concrete that differ in coarse aggregate types. Within these two concretegroups, two types of cement of the same class and two water/cement ratios have beenvaried. Sulphate resistance was examined after 3 and 6 months of immersion in 5%Na2SO4 and 5% MgSO4. Capillary water absorption, sample length change andcompressive strength were studied in hardened concrete and the followingmicrostructural analyzes were performed: MIP, SEM, BSE/EDS, XRD and FTIR. It hasbeen found that structural concrete with apppropriate mechanical properties as well aswith satisfactory durability from the aspect of sulphate corrosion can be obtained bycombination of a coarse recycled concrete aggregate and a binder of an appropriatemineralogical composition.

U cilju implementacije i promocije održivog razvoja u oblasti graditeljstva, sprovedena su obimna eksperimentalna ispitivanja kako karakteristika recikliranog agregata (RCA), tako i karakteristika asfaltnih mešavina sa delimičnom zamenom prirodnog agregata recikliranim. Reciklirani agregat koji je korišćen u istraživanju dobijen je drobljenjem originalnog cementnog betona klase čvrstoće C35/45. U cilju poboljšanja kvaliteta recikliranog agregata, krupan RCA (d>4 mm) je izložen tretmanima hlorovodoničnom kiselinom (potapanjem u 0.1 mol/dm3 HCl) i ubrzanoj karbonatizaciji (koncentraciji CO2 od 4%). Pomenutim tretmanima su u manjoj meri poboljšane karakteristike RCA, pa su dalja ispitivanja uticaja RCA na karakteristike asfalt betona sprovedena samo za netretirani RCA. Eksperimentalnim ispitivanjima je obuhvaćeno 10 asfaltnih mešavina. Osim kontrolne mešavine, formirane su tri grupe mešavina sa delimičnom zamenom sitnog (0/4 mm), krupnog (4/22.5 mm) i sitnog i krupnog (0/22.5 mm) prirodnog agregata recikliranim. Svaku grupu su činile mešavine sa tri različita sadržaja RCA: 15%, 30% i 45%. Projektovane su asfaltne mešavine za noseći sloj kolovozne konstrukcije AC 22 BASE sa ciljanim sadržajem šupljina ispunjenih vazduhom od 5.2%. Glavni deo eksperimentalnog rada je obuhvatio ispitivanje modula krutosti i otpornosti asfalntih mešavina na dejstvo vode, trajnu deformaciju, zamor i niske temperature. Dobijeni rezultati su pokazali da je moguća primena kompletnog RCA (i sitan i krupan agregat); da mešavine sa RCA imaju istu ili bolju otpornost na zamor u odnosu na kontrolnu mešavinu; i da je maksimalna količina RCA u manjoj meri ograničena otpornošću na niske temperature. Na osnovu analize dobijenih rezultata razvijena je metodologija za upotrebu RCA kao delimične zamene prirodnog agregata i date su preporuke za dalja istraživanja. As a part of the implementation and promotion of sustainable construction development, large experimental research was conducted. This research included testing of the recycled concrete aggregate (RCA) and properties of asphalt mixtures in which this aggregate was applied as a partial replacement of the natural aggregate. Recycled concrete aggregate used in the conducted experiments was obtained by crushing of the original cement concrete (strength class C35/45). In order to improve it's quality, coarse RCA was exposed to the treatments with hydrochloric acid (by pre-soaking into 0.1 mol/dm3 HCl) and carbon dioxide (accelerated carbonation with 4% concentration of CO2). Mentioned treatments induced improvements in the properties of RCA, to a lesser extent. Therefore, only untreated RCA was used as a partial replacement of the natural aggregate in production of asphalt mixtures. Experimental research was conducted on the 10 different asphalt mixtures. Three groups of mixtures with RCA were tested in addition to the control mixture. In the first group, only fine aggregate (0/4 mm) was replaced by RCA; in the second group, the replacement was applied only to coarse aggregate (4/22.4 mm), while the third group included mixtures in which both fine and coarse aggregate were replaced by RCA. Each group included three different contents of RCA: 15%, 30%, and 45%. All asphalt mixtures were designed for the base course AC 22 BASE, targeting 5.2% of air entrained voids. Main part of the experiment consisted of different asphalt mixture’s testing, such as measurements of: the stiffness modulus, resistance to water, permanent deformation, fatigue and low temperatures. Obtained results show that application of the total (both fine and coarse) RCA is possible as mixtures with RCA expressed equal or improved fatigue resistance when compared to the referent mixture. Still, the amount of the RCA used should be limited according to its low temperatures resistance. Methodology for the RCA application, when it is used as a partial replacement of the natural aggregate in asphalt mixtures, was developed based on the presented results, together with guidelines for the future research.

Durability of hydraulic engineering structures in most part depends on the resistance of concrete surface to mechanical abrasion. Hydro-abrasion represents a surface damage caused by continuous removal of material due to impact of waterborne hard particles. This form of progressive deterioration of concrete surface occurs, to a varying extent, in almost all hydraulic engineering structures. Therefore, hydro-abrasion wear of concrete in general causes reduction of the service life of a hydraulic engineering structure, as well as an increase in operating costs due to the necessary maintenance, and the downtime of the structure during the repair period. In general, little is known about the onset of concrete hydro-abrasion and about development of this damage in time. Presently, there is no standard testing method for hydro-abrasive resistance of concrete in laboratory conditions, which can to a great extent simulate the natural abrasion conditions. Also, the factors representing the physical, mechanical and structural concrete characteristics, and which affect its resistance to wear have not been sufficiently investigated. In the literature is discussed mostly the hydroabrasive resistance of high-strength concretes made with natural crushed or river aggregate, which are reinforced by addition of the silica powder or micro-reinforcement, with a high quantity of cement (higher than 400 kg/m3). The potential for application of recycled materials and reduced quantity of cement for production of the concretes resistant to hydroabrasion is presented in a limited scope. The paper investigates and analyzes the potential for production of cement concrete in which the cement content has been partially replaced by fly ash or silica powder, and where fine river aggregate has been partially replaced by recycled granulated rubbers, with the addition of micro-fiber (steel or polypropylene), with the aim to increase resistance to hydro-abrasive action. Performances of these concretes in fresh and hardened state were compared with the performances of reference concrete without the partial replacement of cement and fine aggregate and without micro-fibers. The tests of hydro-abrasive resistance of concrete was performed on the original apparatus constructed in the Laboratory of building materials at the Faculty of Civil Engineering and Architecture of Niš, which facilitates that the jet of water and sand mixture impacts the concrete tests slab at a high speed. The parametric analysis of the effects of individual mechanical characteristics on the hydro-abrasive resistance of concrete was done. For the purposes of the research, a total of eighteen types of concrete was made, which can be divided into three groups of six mixtures. The first group consists of the concrete mixes where no partial substation of cement was performed, the second group consists of the concrete mixtures where cement was substituted by filter ash, in the amount of 20% in respect to the cement mass, while the third group consists of the concrete mixes where the cement was substituted with the silica powder in the amount of 10% in respect to the cement mass. Within each group, there is a mixture where a part of fine river aggregate was replaced by the granulated recycled rubber in the amount of 10% in respect to the aggregate volume, followed by two concrete mixtures where polypropylene fibers have been added (monofilament to one and fibrillated to the other mixture), then two mixtures where hooked end steel fibers were (in one those are fibers 30 mm long and in the other those are fibers 50 mm long) and finally, there is the concrete mix without partial replacement of the fine river aggregate with recycled rubber and without the addition of fibers. The conclusions are formulated based on the processed and systematized results of the experimental research, and the performed parametric analysis of the effects of individual mechanical characteristics on the hydro-abrasive resistance of concrete. In general, the most intensive effect regarding increase of hydro-abrasive resistance of concrete is achieved by the partial replacement of the fine river aggregate by the recycled granulated rubber. Also, concrete reinforcement with polypropylene fibers contributes to the considerable increase of hydro-abrasive resistance of concrete, whereby the better effect is achieved using the fibrillated fibers. The addition of steel fibers in concrete does not result in a considerable increase of the hydro-abrasion resistance. The concretes made with the partial replacement of cement by fly ash have lower hydro-abrasive resistance in comparison to the reference concrete, while with the addition of polypropylene fibers, their resistance becomes approximately equal to the resistance of the reference concrete. Partial replacement of cement with silica powder contributes to the increase of hydro-abrasive resistance of concrete. The parameters such as compressive strength, flexural strength, splitting tensile strength, tensile strength determined using „Pull-off“ method, static modulus of elasticity and resistance to abrasion wear can be the factors for prediction of hydro-abrasive resistance of concrete, due to the existence of strong. The behavior of concrete exposed to hydroabrasive action cannot be fully predicted based on the „Drop weight“ tests of the impact resistance of concrete. The accelerate abrasion test method implemented in the research is suitable for analysis of hydro-abrasive resistance of concrete.

Over the last twenty years the two contradictory processes, connected to the durability of concrete structures, were observed: improvement of the quality of concrete mixtures, as a result of a continious growth of the knowledge in technology and of the improvement of codes and standards, led toward the potential durability of concrete structures, and a general decline of the quality of performance of the works, because of gradual reduction in the number of well skilled workers in concreting, affecting a decrease of actual durability of concrete structures. The exceed of the gap between these two mutual opposed processes can only result through a decisive increase of the industrialisation level of the construction process of works, i.e. through the elimination of the effect of „man – factor“ on the quality of performed structures. By use of Self–Compacting Concrete it is possible to achieve this aim. The durability of structures then exclusively depends on the achieved quality of concrete mixture. Developed during last decade of 20th century in Japan and continental Europe, today, Self-Compacting Concrete is applied in USA and United Kingdom as much as in the Middle East. By it’s nature, Self-Compacting Concrete does not need compaction by vibration. Compaction of this concrete, in every part, or in every corner of the formwork, including it’s hardly available parts, is done without any external forces except it’s own weight. These properties are achieved by adding superplasticizers, commonly with new Viscosity Modification Admixtures, or/and determened amount of powders. It is possible to use different mineral additions, where the use of those who are industrial by - product (like fly ash) has multiple environmental benefits. Concept of sustainable development, which beside sociological and economic aspects, include saving of energy, environment protection and preservation of an restorable natural resources, presents strategic determination of various economic sectors. In that way great contribution is expected from construction industry. Lack of natural aggregate in urban areas and increasing distance between deposits of high – quality natural aggregate and building sites, forced building contractors to analyze possibility of change of natural aggregate with recycled materials (masonry, slag, concrete, etc.). On the other hand, huge amount of old concrete exists in urban areas and it’s removal and deposition is a big ecological problem. Aim of this paper is analysis of properties and technology of Self-Compacting Concrete with different mineral additions (lime, fly ash and silica fume), natural and recycled aggregate, considering mixes without recycled aggregate, with third recycled fraction, and with second and third recycled fractions.