RISK MANAGEMENT TOOL FOR IMPROVING PROJECT FLOWS FOR CONSTRUCTION PROJECTS ON EXISTING BUILDINGS

Old cores of European cities make more than 35% of the entire building stock in Europe, which and often form the social, financial, and touristic centers of cities. These old buildings require constant investments in terms of renewal and preservation to retain their usefulness. Existing risk management tools do not provide sufficient support when managing these types of projects. Hence, previously developed risk breakdown structures (RBSs) for projects on existing buildings were extended to enable simpler project management and clear visibility of critical risks. Previous studies focused on RBSs for construction projects in general. Research with respect on real life projects showed that some risk sources posed a greater threat and had more risk triggers than other risk sources. This study identified critical risk sources with respect to existing RBS and conducted a further analysis of these risk sources. The results of the study examined the fully developed RBS for existing building construction projects with further structuring of specific risk sources. Furthermore, the study identified stakeholders and assigned their risk resolution responsibilities

METODOLOGIJA ODABIRA TEHNOLOGIJE SEIZMIČKOG OJAČANJA ZIDANIH ZGRADA

When the decision has been made to seismically strengthen a building, in order to mitigate possible damaging effects of an earthquake, choice of seismic strengthening is entirely left to the expert. The choice is often made without any specific analyses of the need and implementation possibilities, but depends completely on the expert’s knowledge and experience. The article presents the development of the innovative approach to strengthening technique selection for existing buildings that incorporates all important elements that influence the strengthening selection process. The presented model is simple, quick, precise, allowing analytically supported decision making. Although the developed model is designed particularly for masonry buildings, decision support model for strengthening technique selection is adaptable to any building type.Kada je donesena odluka o potrebi za ojačanjem zgrade u cilju preventivne zaštite od potresa, kao pravilom, odabir ojačanja prepušten je stručnjaku. Odabir ojačanja se najčešće provodi bez konkretnih analiza mogućnosti i potreba za određenim pothvatom, već isključivo prema nahođenju i prošlom iskustvu stručnjaka. U članku se predstavlja proces razvoja inovativnog pristupa izboru tehnologija ojačanja postojećih zgrada, a kojim se uzimaju u obzir svi bitni elementi koji mogu utjecati na izbor ojačanja. Predstavljeni model je jednostavan, brz i precizan, te dozvoljava donošenje odluka na osnovu analitički dokazanih činjenica. Unatoč tomu što je model izrađen isključivo samo za zidane zgrade, model za izradu potpore odlučivanja pri odabiru tehnologije ojačanja je prilagodljiv bilo kojem tipu građevina

Construction time-cost model in Croatia

The paper deals with the applicability of the time-cost model for calculating the sustainable construction time for building projects in Croatia. In this model the time is expressed as a function of money in the project, while the specific constants K and B need to be determined. These constants depend on economic characteristics of the country or a larger area, therefore had to be separately calculated for a region with similar economic characteristics. The modelling of the constants was performed for two groups of building projects - the roads and residential and office multi-storey buildings. The obtained results have been analyzed and compared to the corresponding results from abroad

FENOMEN PROJEKTIFIKACIJE I UTJECAJ NA NACIONALNO GOSPODARSTVO – PRIMJER HRVATSKE

Projectification has become an important phenomenon in the field of project studies. Projectification represents an important portion of the gross national product gathering significant resources in all types of industries. There is significant number of micro-level studies investigating this phenomenon but only few have investigated the macro-level design. This paper adopted approach originally implemented in Germany, Norway and Iceland. Aim of this paper is to broaden the scale of the previous research including Croatia as one of the Eastern European post transition countries. This paper offers unique results from the first projectification research of the Croatian economy based on the analysis of 250 companies. Primary data was collected through interviews with company employees. Results reveal the level of Croatian national economy projectification being below 30% enabling sector and cross country comparison. According to results Croatia is still within the range of the European Union countries. These results add to the existing body of knowledge regarding an ongoing research of the projectification phenomenon.Projektifikacija je postala važan fenomen u području istraživanja projekata. Projektifikacija predstavlja važan udio nacionalnog domaćeg proizvoda obuhvaćajući značajne resurse u svim industrijskim sektorima. Postoji značajan broj istraživanja mikro razine, ali svega nekoliko onih koje istražuju fenomen projektifikacije na makro razini. Ovaj rad koristi pristup originalno primijenjen u istraživanju projektifikacije na primjeru Njemačke, Norveške te Islanda. Cilj istraživanja je proširiti opseg prethodne studije uključivanjem Republike Hrvatske kao istočno europske post-tranzicijske zemlje. Rad nudi jedinstvene rezultate prve studije projektifikacije nacionalnog gospodarstva Republike Hrvatske koji se temelje na uzorku 250 poduzeća. Primarni podaci su prikupljeni putem intervjua zaposlenika. Rezultati ukazuju na postojeću razinu projektifikacije nacionalnog gospodarstva ispod razine od 30% omogućujući usporedbu sektora i zemalja. Prema rezultatima Republika Hrvatska se nalazi unutar raspona zemalja Europske unije. Rezultati istraživanja doprinose postojećem skupu znanja istraživačkog područja fenomena projektifikacije

MODELL DER LEITUNG DER QUALITÄTSKOSTEN IN BAUPROJEKTEN

Prikazuju se rezultati istraživanja troškova kvalitete u građevinskim projektima visokogradnje. Opisana je struktura troškova kvalitete i karakteristike komponenata. Utvrđene su vrijednosti troškova kvalitete u ugovorenoj vrijednosti projekata. Provedena je analiza odnosa promatranih komponenata troškova kvalitete i analiza odnosa troškova kvalitete sa drugim ugovornim veličinama – cijenom i rokom. Formuliran je model za upravljanje troškovima kvalitete u građevinskim projektima.Results obtained during quality cost analysis for building construction projects are presented. The quality cost structure and characteristics of individual components are described. The proportion of quality costs in the total contract price of projects is defined. Correlations among individual quality cost components are analysed, and quality costs are compared with other contract parameters - price and completion time. The quality cost management model for construction projects is formulated.Les résultats obtenus au cours de l'analyse des frais de qualité sur les projets de construction sont présentés. La structure des frais de qualité et les propriétés des composants individuels sont décrites. La partie des frais de qualité dans le prix contractuel total de projets est définie. Les corrélations entre les composants individuels des frais de qualité sont analysées, et les frais de qualité sont comparés avec les autres paramètres contractuels - prix et délai. Le modèle de gestion des frais de qualité pour les projets de construction est proposé.Dargestellt sind die Ergebnisse der Forschung der Qualitätskosten bei Bauproblemen des Hochbaus. Beschrieben ist die Struktur der Qualitätskosten und die Kennzeichen der Komponenten. Festgelegt sind die Werte der Qualitätskosten im vereinbarten Wert des Projekts. Durchgeführt ist die Analyse der Verhältnisse der betrachteten Komponenten der Qualitätskosten und die Analyse der Verhältnisse der Qualitätskosten zu den übrigen Vertragsgrössen - Preis und Frist. Formuliert ist ein Modell für die Leitung der Qualitätskosten in Bauprojekten

Leading, lagging and perceptive performance measures in the construction industry

Poor performance management is one of the main reasons for such low image that the construction industry has in the society. It is percieved as the worst, ineffective, inefficient… Even though Key Performance Indicators (KPI) should be at the heart of every performance system, many organizations do not acknowledge their importance and thus are measuring the right things wrong and vice versa. This paper elaborates distinction among three types of KPIs: leading, lagging and perceptive, and explains their role in the performance measuring process within the construction industry. Even though many authors emphasised the importance of implementing KPIs, literature review showed that world’s practice still does not recognize the distinction. Furthermore, survey taken across Croatian construction industry, showed that: 90% of proffesionals understand KPIs’ importance, 71% used some kind of performance indicators, 63% used KPIs for internal benchmarking, 43% showed high interest in such systems, but only 28% understood above-mentioned distinction. The survey also showed that even though the managers percive all three types of KPIs important, they are still not implementing them in the practice. The paper concludes that the use of all three types of indicators is the prerequisite for benchamarking, strategy alignment and realistic goal setting

PRIMJENA RAČUNALNIH APLIKACIJA ZA UPRAVLJANJE PROJEKTIMA U GRAĐEVINSKOJ INDUSTRIJI JUGOISTOČNE EUROPE

Although the construction industry has always been project-oriented, limited attention has been paid to the Project Management Software (PMS), particularly in the transitional countries. This paper contributes to a deeper understanding of the needs of the transitional economies by providing new insight into deficiencies of implementing the Western PMS in the construction industry of Southeast Europe (SEE). Thus, while the construction industries of the developed economies use PMS for a wider range of project management processes, the SEE construction industry still practices management mainly through financial procedures and material planning. Therefore, the PMS originating from developed countries, in the present form, is of little use in transitional economies.Iako je građevinska industrija uvijek bila projektno orijentirana, tijekom proteklih godina, izrazito mala pažnja je dana računalnim aplikacijama za upravljanje projektima (RUP). Ovaj članak doprinosi dubljem razumijevanju potreba tranzicijskih ekonomija, predstavljajući nedostatke uvođenja RUP-a, nastalih u Zapadnim sustavima, u građevinske industrije Jugoistočne Europe (JE). Istraživanje je pokazalo kako postoji značajna razlika u načinu i procesima kojima se upravlja projektima u građevinskim industrijama Zapada u odnosu na praksu u JE. Tako dok Zapadna praksa pokazuje potrebu za korištenjem mnoštva procesa za upravljanje projektima (npr. upravljanje rizicima, niveliranje resursa u planu itd.), građevinska praksa JE se još uvijek temelji na financijskim procedurama i planiranju potrebnog materijala. Zbog ovih razloga može se ustvrditi kako su RUP, koji potječu iz Zapadnih praksa, u svom trenutnom obliku, od male koristi za tranzicijske ekonomije

Assessment of RC Frames for SD Limit State Using Nonlinear Methods of Analysis According to EN 1998-3

Design of structures in seismically active areas according to EN 1998-1 includes a choice between two ductility classes, medium or high, without conditioning by other parameters or favouring any of them. The behaviour factor q is applied as a global reduction factor of internal forces that would develop in the structure in the event of elastic response. According to EN 1998-3 a seismic assessment is determined by comparing the demands with the corresponding capacities. For ductile element, seismic demand and capacity are expressed in terms of chord rotation. The research in this paper was focused on the study of influence of the design ductility classes, as well as of the design seismic actions and the number of frames storeys, on seismic response of reinforced concrete frames designed according to European codes. Seismic performance evaluation of newly designed code-conforming structures is of interest, in order to identify any potential weaknesses and deficiencies in new structures that are designed with appropriate acceptable level of structural damage in the event of a design earthquake. The considered frames were evaluated for the significant damage limit state, for which the return period corresponds to the designed seismic actions. Nonlinear methods of analysis were used, which are the reference methods for assessing seismic performance. The frames designed for high class ductility manifested more favourable seismic performance and the frames designed for lower seismic action had lower values of demand/capacity ratio

Pozne morfološke promene u pulpi zuba molara Wistar pacova sa aloksanskim diabetesom

The aim of this study was examination of late changes in the dental pulp of rats with experimental diabetes. The experiment involved 36 male albino rats, initially 35 days old and 89.45±9.95 g body wight. The animals were separated into 6 equal groups. The first (T1), third (T2) and fifth (T3) groups of animals were given a single dose of alloxan tetrahydrate approximately 80 mg/ kg body weight. Just before the application, the substance was dissolved in physiological saline, and each animal was given 1 ml in the tail vein. The second (C1), fourth (C2), and sixth (C3) group of animals were used as appropriate control groups and received 1 ml of physiological saline injection. Body weights were measured and glycemia was checked weekly. The animals in groups T1 and C1 were sacrificed on the 63rd day, groups T2 and C2 on the 95th day and groups T3 and C3 on the 125th day by decapitation. The block of mandibular molars was taken for histological examination. The results of histological examinations showed stasis, in microcirculation, as well as in large blood vessels of the pulp, and necrosis of the pulp tissue in animals after 63 days of experimental diabetes. Pulps of the animals killed after 95 days showed, besides massive pulp necrosis, abscess forms localized in the mesial horn of the pulp. This evidence was not present in every animal from group T2. Pulps of the animals sacrificed after 125 days showed hydropic degeneration of the pulp with massive and diffuse presence of vacuoles in odontoblasts.Cilj ovog rada je bio ispitivanje poznih promena na pulpi zuba pacova sa eksperimentalnim dijabetom. Eksperiment je izveden na 36 muških albino pacova, starih 35 dana, telesne mase 89.45 ± 9.95 g. Životinje su bile podeljene u 6 grupa. Prva (T1), treća (T2) i peta (T3) grupa životinja primila je jednokratnu dozu aloksan tetrahidrata, približno oko 80 mg/kg mase tela. Neposredno pre aplikacije, supstanca je rastvorena u fiziološkom rastvoru i svakoj životinji je dat 1 ml rastvora u repnu venu. Druga (C1) četvrta (C2) i šesta (C3) grupa životinja bile su kontrolne grupe i dobijale su 1 ml čistog fiziološkog rastvora. Jednom nedeljno merena je telesna masa i glikemija. Životinje grupe T1 i C1 su žrtvovane 63-eg dana, životinje grupe T2 i C2 95-og dana a životinje grupe T3 i C3 125-og dana eksperimenta dekapitacijom. Za histološka ispitivanja uzeti su isečci mandibularnih molara. Rezultati histoloških ispitivanja pokazuju stazu kako u mikrocirkulaciji tako i u velikim krvnim sudovima pulpe kao i nekrozu tkiva pulpe kod životinja žrtvovanih 63-ćeg dana eksperimentalnog dijabeta. Kod nekih životinja žrtvovanih 95-og dana pored masivne nekroze pulpe, u uočavaju se abscesi lokalizovani na mezijalnom rogu. Pulpe životinja žrtvovanih 125-og dana ukazuju na hidropsnu degeneraciju pulpe sa masovnom i difuznom pojavom vakuola u odontoblastima

The development of devices and tools for polymer injection at low pressure

U ovom završnom radu opisan je razvoj uređaja i alata za ubrizgavanje polimera pod niskim tlakom. Opisana je izrada samog uređaja, korišteni materijali pri izradi, sastav upravljačkog ormara te način upravljanja uređaja. Opisan je princip rada uređaja i korištenje alata i prihvata alata te izrada i hlađenje alata. U CAD programu konstruirana je uvodnica kabela te je napravljena simulacija ubrizgavanja mase. Navedena su svojstva MacroMelt 6208 mase te usporedba TechnoMelt postupka s drugim postupcima. Tehnologija ubrizgavanja polimera pod niskim tlakom omogućuje jeftinu izradu odljevka i dobru zaštitu elektroničkih komponenata i sklopova te kablova. Kratko vrijeme ubrizgavanja, kao i brzina hlađenja odljevka čine ovaj postupak pogodnim za serijsku proizvodnju velike produktivnosti