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Resource savings requirements in projects that result from the global resource-saving need stimulate innovation in construction, both in the field of innovative materials and products, and in the improvement of all construction processes. Changes in the project are marked by risks and usually assume the need for additional resources - time and money. Change management differs for a project that is traditionally conducted in a consecutive way from project design to project submission and to a project developed by the BIM approach that seeks to put processes more and more simultaneously. This paper presents a review of the literature that defines the differences between these two approaches and establishes a framework for exploring the possibilities for improving the complex building project created and managed by traditional approach based on the theoretical background. Zahtjevi za uštedama u projektima koji proizlaze iz globalne potrebe za uštedom resursa potiču inovacije u građevinarstvu, kako u području inovativnih materijala i proizvoda tako i u unaprjeđenju svih procesa gradnje. Promjene u projektu obilježene su rizicima te obično pretpostavljaju potrebu za dodatnim resursima - vremenom i novcem. Upravljanje promjenama razlikuje se za projekt koji se vodi tradicionalno na konsekutivan način od projektiranja do predaje projekta i za projekt koji je izrađen BIM pristupom koji nastoji procese postaviti u većoj mjeri simultano. U radu se donosi pregled literature koja definira razlike ova dva pristupa te se na osnovu teorijske podloge postavlja okvir za istraživanje mogućnosti za unaprjeđenje projekta složene zgrade izrađene i vođene tradicionalnim pristupom.

Bioasche ist aufgrund der Erfüllung der Forderungen nach immer größerer Verwendung von erneuerbaren Quellen bei der Energieerzeugung ein unvermeidliches Produkt. Die ökologischen und wirtschaftlichen Probleme bei der Entsorgung von Bioasche können wegen der angemessenen chemischen und physikalischen Eigenschaften durch dessen Verwendung als Rohstoff im Bauwesen verringert werden. Die Abhandlung gibt eine Übersicht über die Untersuchungen der Möglichkeiten der Verwendung von Bioasche beim Straßenbau, unter Berücksichtigung der großen Bandbreite an Eigenschaften, die sie abhängig von der Herkunft der Bioasche und den Verbrennungsbedingungen charakterisieren. Die Abhandlung gibt auch eine Übersicht über die Untersuchungen der Bioasche, die als Produkt der Verbrennung von Biomasse in Wärmekraftwerken auf dem Gebiet der Republik Kroatien entstanden ist. Bioashes are inevitable product of meeting the demands to satisfy the increased use of renewable resources in energy production. Ecological and economic problems of bioash disposal, due to its appropriate chemical and physical properties, can be reduced by its application in the construction industry as raw materials. The paper therefore provides an research overview on various aspects of the bioash application in road construction, in compliance with a range of properties depending on the type of biomass and the conditions of combustion. Also shown is current state of research of bioash generated in the domestic thermal power plants. Biopepeli su neizbježan proizvod ispunjavanja zahtjeva za sve većom primjenom obnovljivih izvora u proizvodnji energije. Ekološki i ekonomski problemi zbrinjavanja biopepela, zbog prikladnih kemijskih i fizikalnih svojstava, mogu se smanjiti njegovom primjenom kao sirovine u građevinarstvu. U radu se daje pregled istraživanja mogućnosti primjene biopepela pri gradnji cesta, uzimajući u obzir velik raspon svojstava koja ga karakteriziraju ovisno o porijeklu biomase i uvjetima izgaranja. U radu je također dan pregled istraživanja biopepela nastalog kao proizvod izgaranja biomase u termoelektranama na području Republike Hrvatske.

In der Abhandlung wird eine Übersicht über die modernen heuristischen Techniken und Methoden der mathematischen Programmierung dargelegt. Vorgestellt werden moderne Werkzeuge für die optimierte Modellierung, es werden die häufigsten Probleme der Optimierung im Bauwesen dargelegt und es wird eine Übersicht ihrer aktuellen Anwendungen gegeben. Die Abhandlung betont den Untersuchungsbereich aktiver Modelle der Optimierung, die durch BIM unterstützt werden, mit dem Ziel eines besseren Bauprozessmanagements. Eine beschleunigte Entwicklung der Entscheidungsmodelle, welche die Optimierungsmethode und die Informationssysteme kombinieren, kann für die nahe Zukunft klar vorausgesehen werden. A review of current heuristic techniques and mathematical programming methods is presented in the paper. Modern optimisation modelling tools are presented, common construction optimisation problems are described, and an overview of their recent application is given. It is also stressed that there is ample room for further research on active BIM-based optimisation models, aimed at better management of construction processes. Accelerated development of decision-making models, which combine optimisation methods and information systems, can be clearly predicted for the near future. U radu je dan pregled suvremenih heurističkih tehnika i metoda matematičkog programiranja. Predstavljeni su moderni alati za optimizacijsko modeliranje, izlažu se najčešći problemi optimizacije u građevinarstvu i daje pregled njihovih nedavnih aplikacija. Rad je istaknuo prostor istraživanja na aktivnim modelima optimizacije, koji su podržani BIM-om s namjerom boljeg upravljanja građevinskim procesima. Ubrzani razvoj modela odlučivanja, koji kombiniraju optimizacijske metode i informacijske sustave, jasno se može predvidjeti za blisku budućnost.

Brettsperrholz (eng. ross Laminated Timber – CLT) ist ein innovatives plattenförmiges Produkt mit einer geschichteten Struktur und hervorragenden physikalischmechanischen Eigenschaften. Aufgrund der hohen Steifigkeit und Tragfähigkeit in Ebene und senkrecht zur Ebene des Elements wird es meistens in Form von Wand- oder Deckenpaneelen verwendet. Die günstigen ökologischen, ästhetischen und energiewirtschaftlichen Eigenschaften verbessern dieses noch zusätzlich. Die Abhandlung gibt eine zusammenfassende Übersicht über die bisherigen Untersuchungen des CLT mit Betonung auf der erforderlichen Harmonisierung der bestehenden Vorschriften und dessen Integration in die europäische Norm Eurocode 5 für Holzkonstruktionen. Cross laminated timber is an innovative plate-shaped product presenting a laminated structure and excellent physicomechanical properties. Due to its high stiffness and in-plane and out-of-plane bearing capacity, it is most often used in form of wall or floor panels. Favourable environmental, aesthetic and energy properties further enhance its qualities. The paper is a summary of CLT research conducted so far, with an emphasis on the need to harmonise existing regulations and include this product in the European standard for timber structures Eurocode 5. Križno lamelirano drvo (eng. Cross Laminated Timber – CLT) inovativni je pločasti proizvod slojevite strukture i izvrsnih fizikalno-mehaničkih svojstava. Zbog velike krutosti i nosivosti u ravnini i okomito na ravninu elementa najčešće se primjenjuje u obliku zidnih ili stropnih panela. Povoljna ekološka, estetska i energetska svojstva dodatno ga pospješuju. Rad prikazuje sumarni pregled dosad provedenih istraživanja CLT-a, s naglaskom na potrebnu harmonizaciju postojećih propisa i njegovo uključivanje u europsku normu za drvene konstrukcije Eurokod 5.

Dürre ist ein extremes hydrologisches Phänomen, das große wirtschaftliche und ökologische Schäden verursacht. Die Identifizierung und Quantifizierung von Dürre wird mittels verschiedener Methoden durchgeführt. Im kontinentalen Raum Kroatiens ist für 15 meteorologischen Stationen im Zeitraum von 1981 bis 2011 eine Analyse der folgenden fünf Methoden zur Identifizierung von Dürre durchgeführt: standardisierter Niederschlagsindex, Dezil-Methode, Normalprozentsatz, Index der Niederschlagsanomalie und Schrittverfahren. Die Ergebnisse haben gezeigt, dass die einzelnen Methoden ihre Besonderheiten haben, aber für das analysierte Gebiet anwendbar sind. Der standardisierte Niederschlagsindex hat eine bedeutende Korrelation zur Dezil- Methode, dem Normalprozentsatz und dem Index der Niederschlagsanomalie. Drought is an extreme hydrological event that causes great economic and environmental damage. Various methods are used for the identification and quantification of drought. The analysis of five drought identification methods was conducted for continental Croatia on 15 weather stations in the period from 1981 to 2011: standardised precipitation index, deciles index, percent of normal precipitation, rainfall anomaly index, and threshold level method. Results have revealed that each of these methods has its specific features but that all are applicable for the area under study. There is a significant correlation between the standard precipitation index and the deciles index, rainfall anomaly index, and percent of normal. Suša je ekstremna hidrološka pojava koja izaziva velike gospodarske i ekološke štete. Identifikacija i kvantifikacija suše provodi se primjenom različitih metoda. Za područje kontinentalne Hrvatske, na 15 meteoroloških postaja od 1981. do 2011. godine, provedena je analiza 5 metoda za identifikaciju suše: indeks standardiziranih oborina, metoda decila, postotak od normale, indeks anomalije oborina i metoda koraka. Rezultati su pokazali da svaka od metoda ima svoje specifičnosti, ali su sve primjenjive za analizirano područje. Indeks standardiziranih oborina ima značajnu korelaciju s metodom decila, postotkom od normale i indeksom anomalije oborina.

Although aluminium is a structural material that has been present on the market for a long time, its use is not in accordance with the benefits that can be achieved by its application. While it is similar to steel, there are significant differences between these materials, both in manufacturing and in physical and mechanical properties. Due to such differences, these materials exhibit distinct features in the areas of cross sectional and elements stability and welds. These areas are still an active field of research due to a large number of alloys, processing methods, and cross-sectional shapes. Obwohl Aluminium schon lange als Konstruktionsmaterial bekannt ist, wird es nicht den Vorteilen seiner Anwendung entsprechend eingesetzt. Auch wenn das Material mit Stahl verglichen werden kann, bestehen bedeutende Unterschiede, sowohl in der Herstellung, als auch in den physikalischen und mechanischen Eigenschaften. Folglich umfassen die Stabilität der Querschnitte oder Elemente und die Schweißflächen eine Reihe von Besonderheiten, die weiterhin einen aktiven Forschungsbereich darstellen, insbesondere aufgrund der großen Anzahl von Legierungen, Verarbeitungsmethoden und Querschnittsformen. Iako je aluminij već dugo prisutan konstrukcijski materijal, uporaba mu nije u skladu s dobrobitima koje se ostvaruju njegovom primjenom. Sličan je čeliku, no između njih postoje značajne razlike kako u proizvodnji, tako i u fizikalnim i mehaničkim svojstvima. Upravo iz tih razlika proizlaze posebnosti u područjima stabilnosti dijelova poprečnih presjeka i konstrukcijskih elemenata te u područjima zavara. Ta polja još uvijek predstavljaju aktivna područja istraživanja zbog velikog broja legura, obrada i oblika poprečnih presjeka profila.

Waste water must be treated prior to discharge into the recipient. One way of treating waste water is constructed wetland for wastewater treatment. Constructed wetlands are complex biological systems that mimic the processes in nature. These systems are simple, acceptable and economically feasible way of water protection. This paper describes the constructed wetlands through device types, their advantages and disadvantages, the basics of design and hydraulics. Especially analyzed constructed wetland Vinogradci. Otpadne vode se moraju pročistiti prije ispuštanja u recipijent. Jedan od načina pročišćavanja otpadnih voda je pročišćavanje biljnim uređajima. Biljni uređaji su kompleksni biološki sustavi koji oponašaju procese u prirodi. Jednostavan su, prihvatljiv i ekonomski opravdan način zaštite voda. U radu su opisani biljni uređaji (umjetne močvare) kroz vrste uređaja, njihove prednosti i nedostatke, osnove projektiranja i hidraulički proračun. Posebno je analiziran biljni uređaj Vinogradci.

Following disastrous earthquakes in Alaska and in Niigata in 1964, Seed and Idriss developed and published a method for evaluating liquefaction resistance of soils termed the ‘‘simplified procedure’’. For a long time it has been considered that the presence of the building reduces the risk of liquefaction, but after the recent earthquakes (Kobe 1995. and Kocaeli 1999.) it was observed that the liquefaction occurred under the foundations of buildings, although it has not been observed in the free field around buildings. This paper analyzes and compares soil liquefaction potential in the free field and beneath the building, for two relatively soft soil profiles under the influence of two strong motions with different frequency character and magnitude. A linear-elastic time history analysis was conducted using computer program SAP2000 for the free field case and case with presence and response impact of a shallow founded reinforced concrete frame structure. In addition, basic dynamic response of the structure in interaction with the soil is presented and a short comparison is made opposite to the widely accepted rigid-base structure assumption. Nakon katastrofalnih posljedica potresa na Aljasci i u Niigati 1964. godine, Seed i Idriss su razvili i objavili metodu za procjenu otpornosti tla na likvefakciju pod nazivom „pojednostavljeni postupak“. Dugo vremena se smatralo kako prisutnost građevine smanjuje opasnost od pojave likvefakcije, no nakon nedavnih potresa (Kobe 1995. i Kocaeli 1999.) uočeno je kako se likvefakcija pojavila ispod temelja građevina, iako nije došlo do njezinog pojavljivanja na slobodnim površinama tla u okolici građevina. U ovome radu analiziran je i uspoređen likvefakcijski potencijal tla neopterećenog objektom i tla ispod građevine, za dva profila relativno mekog tla u Osijeku pri djelovanju dva potresa različitog frekventnog karaktera i magnitude. Linearno-elastične analize vremenskim zapisom provedene su koristeći računalni program SAP2000 za slučaj neopterećen objektom i za slučaj prisutnosti i utjecaja odziva plitko temeljene armiranobetonske okvirne konstrukcije. Dodatno su prikazani i osnovni dinamički odzivi same konstrukcije u interakciji s tlom, te je dana kratka usporedba s općeprihvaćenim modeliranjem apsolutno krutih oslonaca konstrukcije.

This paper presents an overview of the properties of porous concrete, and the advantages of its use in pavement structures. Two mixtures of pervious concrete and a reference concrete mixture commonly used for concrete pavements are prepared and their properties compared: consistency, compressive and flexural strength, porosity and density, dynamic modulus of elasticity, as well as permeability. The possibility of their application in concrete pavements is estimated in accordance with the requirements given in General technical conditions for roadworks. Mixture with a small amount of cement and addition of superplasticizer did not meet minimum porosity and permeability required for pervious concrete. In contrast, a mixture with a higher amount of cement and without the addition of superplasticizer was evaluated as pervious one, but does not have a compressive strength required for road construction. Therefore, it is necessary to direct further research towards improving the compressive strength of mixtures of pervious concrete. U radu je dan pregled svojstava poroznog betona te prikazane prednosti njegove uporabe u kolničkim konstrukcijama. Pripremljene su dvije mješavine poroznog betona i mješavina referentnog betona, uobičajeno korištena za izradu betonskih kolničkih konstrukcija, te uspoređena njihova svojstva: konzistencija, tlačna i vlačna čvrstoća, poroznost i gustoća, dinamički modul elastičnosti te propusnost. Procijenjena je i mogućnost njihove primjene u betonskim kolničkim konstrukcijama, sukladno uvjetima propisanim u Općim tehničkim uvjetima za radove na cestama. Mješavina s malim udjelom cementa i dodatkom superplastifikatora nije udovoljila najmanje zahtijevanoj poroznosti i propusnosti za porozne betone. Nasuprot tome, mješavina s većim udjelom cementa i bez dodatka superplastifikatora ocijenjena je kao porozna, no ne posjeduje tlačnu čvrstoću potrebnu za kolničke konstrukcije. Stoga, potrebno je daljnja istraživanja usmjeriti ka poboljšanju tlačne čvrstoće mješavina.

In this paper analysis of application of geotextiles for filters and drainage in geotechnical and hydrotechnical works is presented. The mechanisms important for functioning of geotextiles as filters related to clogging, blocking, and reduction of pore pressure in the filter-zone, are analyzed. Important criteria for selection of geotextiles as filters, based on available literature and relevant national guidelines, are summarized and compared. Examples of selection criteria for geotextile filter on highways and landfills are presented. U radu se obrađuje primjena geotekstila za filtre i drenaže u geotehničkim i hidrotehničkim zahvatima. Analizirani su mehanizmi važni za dobro funkcioniranje geotekstila kao filtra koji se odnose na začepljenje, blokiranje i smanjenje pornog tlaka u zoni filtra. Na temelju raspoložive literature napravljen je pregled kriterija za izbor geotekstila kao filtra, u što su uvršteni i važeći nacionalni pravilnici. Prikazan je primjer definiranja kriterija za izbor geotekstila za filtar za ceste i za odlagalište otpada.