Modelling of response of architectural objects under the impact of blast induced vibrations in open pits

У овој дисертацији су изучавани померање тла и натпритисак ваздушног удара који су проузроковани минирањем, као и њихови утицаји на околне објекте (куће, домаћинства), у површинским коповима кречњачког каменог агрегата. Кречњак је одабран као репрезентативна стена за испитивање вибрација тла, будући да је то најраспрострањенији тип стене у Србији и да се најчешће користи у грађевинске сврхе. Такође, на кречњаку је урађено много експерименталних истраживања потреса проузрокованих минирањем. Приликом извођења редовних радова на минирању у каменоломима кречњака мерене су брзине осциловања тла у близини околних објеката. Утицаји потреса изазаваних минирањем, у складу са постојећом законском регулативом и инжењерском праксом, процењени су коришћењем конвенционалних предиктора. Тачност (поузданост) предвиђања коришћењем конвенционалних предиктора процењена је у односу на забележену максималну брзину осциловања тла. Као резултат истраживања предложен је нови модел за процену утицаја коришћењем вештачких неуронских мрежа са три главне улазне јединице (укупно експлозивно пуњење, максимално пуњење по интервалу успорења паљења експлозива и растојање од места минирања до мерног места), са једним скривеним слојем и једним излазом (максималном брзином осциловања тла). Утицај на постојеће објекте процењен је поређењем максималних брзина осциловања са вредностима дефинисаним постојећим вибрационим стандардима. Ради детаљније процене стварних утицаја потреса изазваних минирањем на околне куће извршена је нумеричка анализа напрезања и деформација у елементима конструкције ових објеката. Овај поступак представља нестандардну методу у анализи утицаја од минирања на архитектонске објекте. Понашање околних објеката под дејством потреса од минирања моделовано је методом коначних елемената коришћењем академских и комерцијалних софтверских пакета. Регистровани временски записи искоришћени су за директну динамичку анализу објеката у околини места минирања. Резултати добијени овим поступком показују који су елементи најоптерећенији и на којим местима се могу очекивати појаве првих оштећења. Та места, као места појаве првих потенцијалних оштећења, морају бити предмет посебне пажње током извођења минирања. Резултати анализе околних објеката показали су да су напрезања и деформације од изведених минирања знатно мања од дозвољених, што је и очекивано за минирања изведена према важећим стандардима. Са циљем да се утврди утицај потреса од минирања на типске архитектонске објекте...In the present dissertation analyses of the ground motion and air-blast overpressure induced by blasting, as well as their effects on neighbouring buildings (houses, households), in limestone quarries is given. Limestone is chosen as a representative rock unit for investigating the ground vibration because it is the most common rock type in Serbian quarries, and limestone is mostly used rock type for civil engineering purposes. Moreover, there have been many experimental investigations carried out on blast-induced vibrations in limestone. Peak particle velocity near neighbouring structures was measured during ordinary blasting operations in limestone quarries. The effects of blast-induced ground motion were evaluated by conventional predictors, in accordance with legal regulations and engineering practice. Their predictive power was estimated in relation to peak particle velocity. A new artificial neural network model for the prediction of blast impact on building was introduced with three input units (total charge, maximum charge per delay and distance from explosive charge to monitoring point), with one hidden layer and one output unit (peak particle velocity). Effects on existing architectural buildings were estimated by comparing peak particle velocities with values defined by existing vibration standards. In order to more precisely evaluate real effects blast-induced ground motion on neighbouring buildings, a numerical stress – strain analysis of structural elements was carried out. This procedure is a non-standard method in analysis of the impact of blasting on surrounding objects. Surrounding buildings were modelled with finite element method using academic and commercial software packages. Measured time recordings were used for the direct dynamics analysis. The obtained results indicate which elements are the most loaded and on which points damages can be expected to occur first. The results of calculations show that blasting performed in accordance with positive vibration standards cause far less stresses and strains than allowed thus avoiding damages on buildings..

Sustainable model for regional hospitals in humid tropical climate

Developing countries are facing numerous challenges in the process of providing adequate health care to often deprived and diminished social groups. In countries and regions with poor road infrastructure, this often means that the population outside major urban centres is even physically incapable of getting some sort of health aid in a timely manner. Being a country made up of a mainland territory and five islands in Gulf of Guinea, almost entirely covered by tropical rainforest, Equatorial Guinea is a showcase of various obstructions in developing effective health care system. The sustainable primary, secondary and tertiary health care assumes good accessibility as well as proper understanding of local conditions. The paper presents a model for sustainable health care building – a local hospital capable of providing all basic types of health service while retaining a high level of technical independence. The architectural design for a regional hospital was developed aiming to maximize the use of natural ventilation, daylight and rainwater management, leaving the operation block, laboratory and intensive care unit practically the only parts of the structure that would need mechanical air conditioning. The layout was designed having in mind local culture and customs, thus offering a possibility of strong integration with local community, and the building technology was thought over to enable efficient and costeffective construction and proper resilience for tropical rainforest environment. The result is a structure providing for contemporary, high quality medical service, interpreting local climatic and cultural contextual premises through modern architectural expression. Some design features developed for regional hospital were also explored in somewhat different conditions – a major clinical centre (in Malabo, the capital) and a local health centre with the basic services for the most remote areas

Municipality policy as key factor for the role of architecture and technology in public health

The construction of the so-called "social infrastructure" (kindergartens, schools, health centres, hospitals), which is the basis for a "public health" in a broader sense, in many countries is led by the administration (state and municipal). The quality of the built environment largely depends on the quality of financier, in this case embodied in some kind of state/municipal authorities, committees and civil servants. In this paper, an example of the application of up to date high-tech design methods and technologies in the design and construction of public buildings is presented. Belgrade public buildings designed and constructed in the period 2009 – 2013, is shown. The first five projects for construction of energy efficient kindergartens (up to passive house standard) with the use of renewable energy sources and realised through architectural competition, were considered as a passing fad, but such a practice has become standard procedure for the design of the other public buildings, and even the only option for the construction project of 1400 social apartments in Borča. The paper presents these projects, and, in particular, highlights the necessary processes and procedures established to ensure that these projects would be implemented

Novi hemijski dodatak svežem betonu za izvođenje tunelske obloge u ekstremnim zimskim uslovima

A new type of calcium-nitrate and urea-based chemical admixture is proposed, in order to maintain the compressive strength of fresh concrete exposed to very low temperatures (below to - 250C), including a sudden transition to positive temperatures at an early age. The applied admixture has no negative effect on compressive strength of specimens cured in water at 200C. When it is cured under three different frost regimes, concrete specimens with admixture show over three times higher compressive strength, in comparison to specimens without admixture. The implications of such improved concrete composition are discussed in reference to the tunnel lining design.U radu se predlaže novi tip hemijskog dodatka betonu na bazi kalcijum-nitrata i uree, sa ciljem održavanja čvrstoće na pritisak svežeg betona izloženog vrlo niskim temperaturama (do -250C), uključujući i uticaj iznenadnih velikih temperaturnih amplituda (prelaze od negativnih ka pozitivnim temperaturama). Primenjeni dodatak ne utiče nepovoljno na čvrstoću na pritisak uzoraka betona negovanih u izotermalnim uslovima na temperaturi od 200C. Kada se svež beton izloži uticaju različitih režima mraza, uzorci sa dodatkom pokazuju gotovo tri puta veću pritisnu čvrstoću u poređenju sa uzorcima bez dodatka. Primena betona sa predloženim aditivom u praksi razmatra se u odnosu na postojanost i stabilnost tunelske obloge sa prskanim betonom

The Origin of Water And Its Meaning for Planet Earth

U radu je dan opis podrijetla vode na planeti Zemlji i njezino značenje u prošlosti i sadašnjosti. Analizirani su razmjeri kretanja vode na zemlji, njihove značajke, kao i glavni izvori dostupne vode na zemlji izraženi kroz postotni udio na globalnoj razini. Također je razmatran nastanak vode u Svemiru i proizvodnja kisika u ranoj fazi nastanka planeta. Fokus rada bazira se na održanju kvalitete vode dostupne na Zemlji te pojavi globalne varijabilnosti intenziteta oborina koje u zadnjih nekoliko desetljeća mijenjaju značajke velikih svjetskih površina kroz procese velikih suša i poplava. Kroz rad su opisani neki od najznačajnijih primjera eksploatacije pitkih voda u svijetu kroz površinske i podzemne rezerve vode. Analizirane su mogućnosti povećanja proizvodnje hrane za ljudske potrebe u pogledu povećanja zemljišta kroz tehnološki napredne metode te zaštita vodnih resursa uslijed klimatskih promjena. Dan je osvrt na značajke kvalitete prirodne vode u medicini i industriji, poboljšanje sanitarnih uvjeta, utjecaj ljudskog zagađenje na globalnoj razini, gospodarski rast i problem smanjenja vode, kao i globalni problem ispuštanja nepročišćenih otpadnih voda u recipijente i, posljedično, ugrožavanje flore i faune.This paper gives a description of the origin of water on planet Earth and its importance in the past and the present. The paper presents the analysis of water flow extent on Earth, its characteristics, as well as the main sources of available water on the planet, expressed through a percentage share on a global scale. It also deals with the origin of water in the Universe, as well as the production of oxygen at the early stages of the planet’s formation. The focus of the paper is based on maintaining the quality of water available on Earth and the global variability of precipitation intensity that has changed the characteristics of large world surfaces through significant drought and flood processes over the last decades. Throughout the paper, some of the most important examples of exploitation of drinking water in the world through the surface and underground reserves of water are described. The possibilities of increasing the production of food for human needs in terms of increasing land through technologically advanced methods and the protection of water resources due to climate change are analyzed. At the end of the paper, there is a review of the characteristics of natural water quality in medicine and industry, sanitary conditions improvement, the impact of global pollution on human beings, economic growth and the problem of water scarcity, as well as the global problem of discharging untreated wastewater into the recipients and consequently endangering flora and fauna

The Equation for the Optimum Dosage of Coagulant for Water Treatment Plant

This paper shows the importance of the equation for the optimum dosage of coagulant and its application to water treatment plant. The optimum coagulant dose during the operation of the water treatment plant "Gorina" in Serbia was determined in a laboratory by means of the jar-test, which fully simulates the conditions of flocculation chambers in the facility. Experimental data fitting yielded a polynomial equation that can be used for the determined coagulant doses. In general, without a jar test, the equation can be used to reliably determine the optimum coagulant dose for application in the water treatment plant, which will purify raw water to a proper inter-stage turbidity value, and will guarantee that the treated water quality will correspond to the Regulation on Hygienic Quality of Drinking Water. The presented analysis of trial run results for the water treatment plant "Gorina" in Serbia showcases the benefits of applying the equation of optimum coagulant doses to achieve top drinking water quality

Determination of the Mohr-Coulomb Material Parameters for Concrete under Indirect Tensile Test

This paper presents determination of the Mohr-Coulomb material parameters for concrete under indirect tensile testing, design of experiments and numerical simulations. Experiments are designed to control input variables associated with inhomogeneous starting material, sample preparation and testing equipment. Statistical analysis of the experimental data is applied in order to correlate material's deformational behaviour with change in cement content. Presented paper discusses a simple method, based on experimental and theoretical framework, to determine two material parameters for concrete: cohesion (c) and angle of internal friction (φ) from indirect tensile test. Cohesion is obtained from experimental results using elastic and plastic theory of concrete deformation. Prandtl's theory is applied to obtain the angle of internal friction from measured bearing capacity and cohesion. Numerical analysis by finite-element method is used for verification of experimental results, employing step-by-step integration procedure for solving the boundary value problem

Attitudes of pharmacists about anthocyanin-based products from blueberry fruit in the pharmacies

The attitudes of pharmacists about anthocyanin-based products from blueberry in the pharmacies were tested with electronic based questionnaire. In the study, 107 pharmacists from the Republic of Serbia and the Republic of Srpska participated, mostly females (84.1%), over 30 years of age who work in pharmacy chains (3 or more pharmacies) (79.4%). When asked if they have any of the anthocyanin-based products from blueberry fruit in the pharmacy, the majority answered in affirmative (72.0%) and that these are dietary supplements for maintaining eye health (76.9%). Half of the surveyed pharmacists (50.5%) answered that they only sometimes recommend these products. More than 50% were familiar with the pharmacological action of anthocyanins, and as many as 64% that anthocyanins achieve their positive effect on vision in low light by regenerating visible purple, rhodopsin. Also, the pharmacist knew other pharmacological activities of anthocyannins, as vasoprotective (52.3%), antioxidant (83.2%) and anti-inflammatory (44.9%). A large number of respondents knew that carotenoids (lutein and zeaxanthin), in addition to anthocyanins, also show a beneficial effect on vision. Finally, it can be concluded that pharmacists in pharmacies lack knowledge about the pharmacological effect of anthocyanins and that we need to work on educating pharmacists about the effects of these herbal pigments and herbal ingredients in general.80th FIP World Congress, Seville, Spain, 2022Poster presentatio

The quantity of anthocyanins in blueberry fruit based dietary products and juices

In the pharmacies of Republic of Serbia, three dietary products and food supplements with blueberry fruit preparations intended to improve eyesight were found and the content of anthocyanins in them was analyzed. According to Ph. Eur. 10, colorimetric method was used for determination of anthocyanins, which was given in the monograph of Myrthilli fructus recens. For compairing, the content of anthocyanins in two juices with blueberry fruit and other fruits with anthocyanins (aronia, grape) was analysed using an AOAC colorimetric method given by Lee et al. (2005). Retin activ (ESI srl, Italy) a dietary product with a special medical purpose, contains vitamins A, C, E, 15 mg of dry blueberry extract standardized at 25% anthocyanosides, lutein and zeaxanthin. The advice of the manufacturer for use is one capsule a day. Our analysis have shown that Retin activ in one capsule contain 8.35 ±0,17 mg of anthocyanins, calculated as cyanidin 3-O-glucoside chloride. Pro-Visio tablets (United Pharma, Bratislava, Slovakia), a food supplement with lutein, zeaxanthin, 20 mg of blueberry extract, vitamin E and selenium, contained 5.14±0.18 mg of anthocyanins, calculated as cyanidin 3-O-glucoside chloride in one tablet. The advice of the manufacturer for use is one capsule a day. Visionace Original tablets (Vitabiotics, London, UK) contain 23 components including blueberry extract (60 mg) and 0.02±0.0089 mg of anthocyanins per tablets. The juices, Bravo - blueberry (RAUCH SERBIA DOO) and Nectar - apple, aronia, blueberry and grape (Nectar DOO, Serbia), contained 42.57±2.66 mg/L and 31.80±0.01 mg/L of anthocyanins, respectively. According to the literature, blueberry anthocyanins has been reported to enhance night visual acuity and contrast sensitivity and are used in the supplements to improve vision health. Older studies (Vannini et al., 1986) have shown significant improvement of the pupillary muscle contraction in reduced light conditions in healthy young subjects after administration of 240 mg of blueberry extract containing 36% anthocyanins. The claimed effect refers to an improvement of visual adaptation to the dark. Newer studies were contradictory. JECFA has established an Acceptable Daily Intake (ADI) of 2.5 mg/kg bw/day for anthocyanins from grape skin. The dose of 50 mg of anthocyanins of black current concentrate have shown positive effect after 30 min of dark adaptation compared before and 2 h after intake of test drink in 12 healthy subjects (Nomi et al., 2019). In conclusion, our results suggest that the best option for better eye health is to use products with concentrated blueberry fruit extracts instead of juices, but the intake of at least 50 mg of anthocyanins per day should be ensured. References 1. Lee J., Durst RW, Wrolstad E., Journal of AOAC International, 88:5, 1269-1278, 2005 2. Vannini L., Samuelly R., Coffano M., Tibaldi L. Bollett Ocul, 65 (6):569-577, 1986 3. Nomi Y, Iwasaki-Kurashige K., Matsumoto H., Molecules, 24(18): 3311, 201980th FIP World Congress 2022, Seville, SpainPoster presentatio