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Understanding how climate change accelerates or slows down the process of material deterioration is the first step towards assessing adaptive approaches for the preservation of historical heritage. Analysis of the climate change effects on the degradation risk assessment parameters like freeze-thaw cycles and salt crystallization is also a key parameter when considering mitigating actions. Due to the vulnerability of cultural heritage in Iran to climate change, the impact of this phenomenon on basic parameters like temperature was analyzed. Choosing an appropriate regional climate model is the first and most crucial step in the analysis of climate change effects on heritage. The outputs of two different regional climate models: the ALARO-0- SURFEX model (Ghent University, Belgium) and the REMO model (HZG-GERICS, Germany) were analyzed to find out which model is more adapted to the region. So the focus of this research is mainly on the evaluation process to find a feasible approach for validation study to determine the reliability of each model. For model validation, a comparison between model data and observations was performed for 30 years from 1980-2017. Besides, some climatic parameters which are likely critical for heritage like freeze-thaw cycles were studied to find out how reliable these models are in the field of building pathology.

Current Topics and Trends on Durability of Building Materials and Components. Proceedings of the XV edition of the International Conference on Durability of Building Materials and Components (DBMC 2020) Barcelona, Spain 20 – 23 October 2020, ISBN:978-84-121101-8-0

Bio-based materials are gaining importance in the building industry, as the focus on sustainability and life-cycle-assessment has increased substantially over the last decade. Wood and wood-engineered products as well as insulation materials made from cellulose, wood, flax, hemp, etc. are increasingly used. These materials are made from renewable resources and with considerably lower energy consumption than various other building materials, such as insulation polymers, steel and concrete. As steel can corrode and concrete can rot, so can bio-based building materials degrade over time when exposed to those conditions that favour decay. Since fungi cause not only aesthetical degradation, but can also severely compromise the structural integrity of a building component this is critical for any service life approach. Consequently, a proper understanding of the fungal susceptibility of bio-based materials is needed, both for optimal application of bio-based materials as for the design of new materials. Based on a combination of tests we try to unravel the role of the material’s chemical components, structure and moisture dynamics on its fungal susceptibility, as well as the interaction between those material characteristics. In a first test set-up, the ‘paste test’, the material’s structure is removed and fungal growth is assessed over time in 2D, with only the material’s chemical components playing a role. In the second test set-up, the ‘X-ray CT test’, fungal development is assessed non-destructively in 3D with X-ray CT, giving an indication of moisture production and distribution over time, in relation to the material’s structure. By comparing the results, we have a better idea of how much each material characteristic influences fungal susceptibility. This knowledge can then be used for optimising fungal testing of bio-based materials, ensuring optimal application and providing the building industry with the confidence they need to pave the way to a more sustainable future.

During a rain event, most of the raindrops reaching the facade either splash back or run off the exterior surface of the facade. However, it is evident that also a portion of the water infiltrates through the open joints of a ventilated facade. The infiltrated water may either be drained in the cavity to the bottom of the wall or reach the insulation layer. If there are any deficiencies present in the insulation layer or at the connection of the brackets, the infiltrated water might introduce problems. Additionally, if the cavity is not able to drain all the infiltrated water or adhered droplets to one of the cavity surfaces do not dry out, moisture problems might occur. Experiments were conducted to determine the infiltration rate through ventilated facades with open joint widths of 5 mm, 10 mm and 15 mm and cavity widths ranging from 190 mm to 40 mm. It was observed that the amount of infiltrating water was larger for larger joints widths. Due to the larger kinetic energy of the drops flowing through the larger joint widths, the drops were able to reach the exterior surface of the insulation layer, even for large cavity widths. The results from the experimental assessment were used as input parameters for hygrothermal simulations to determine the risk of moisture problems.

Capillary imbibition is a transport phenomenon occurring in concrete structures exposed to weathering, frequently in direct connection with the resistance against different deterioration processes. This property depends on the volume and connectivity of pores. For ground granulated blast-furnace slag (GGBFS) and fly ash blended concrete mixes, the pore refining action of these supplementary cementitious materials plays a positive role in the disconnection of the capillary porosity and consequent reduction of the capillary imbibition rate. Moreover, for this particular transport process, primary and secondary transport rates can be defined in connection with different driving mechanisms. This allows a complementary description of the pore structure of concrete. In this paper, blended concrete mixes were prepared by substituting 20, 40 and 60 % of OPC by GGBFS, and 20, 30 and 40 % of OPC by fly ash. The pore structure of these concretes is assessed by water absorption under vacuum and mercury intrusion porosimetry after curing periods of 28 and 90 days. Long-term capillary imbibition tests were also performed and primary and secondary imbibition rates are computed by a novel approach that considers their linear evolution with the fourth root of time. Results show the refinement action of GGBFS and fly ash by a softening in the transition stage between the primary and secondary imbibition periods. A low water flow rate is consequently correlated with the increased tortuosity of samples.

Construction project costs often reach values higher than planned. Accuracy in project cost estimation is one of the most important criteria for project success, even for its sustainability.The main idea of this research is to examine the relationship between realized cost and contracted cost values for residential buildings. The aim of the research is to determine the mathematical relationship between realized and planned costs in the project implementation phase by using a few mathematical methods and some machine learning methods in comparison to linear regression. This would enable validation of methods themselves by comparing and evaluating the obtained relevant parameters.Comparison would be performed on two levels, based on its general characteristics, as well as on the results of their application on the basis of 24 building reconstructions and new buildings by comparing the mean absolute percentage error (MAPE) and the determination coefficient (R2) using Predictive Modelling Software DTREG (pronounced D-T-Reg). The relationship of realized and planned costs will be determined for the building as a whole and for certain types of construction works. That relationship would enable more realistic budget planning of similar future projects. Cost overrun factors will be analysed for particular types of construction works, as well as the probability of their occurrence, and what measures should be undertaken to prevent or reduce them in similar future projects. The phenomenon known in project planning as "optimism bias" will be analysed in the context of research focus of exceeding the construction cost.

The Palace of Westminster, commonly known as the Houses of Parliament, serves as the\ud meeting place of the House of Commons and the House of Lords and is situated on the north bank of\ud the River Thames in London, England. The site is part of the UNESCO Westminster World Heritage\ud Site. The building was constructed of magnesian limestone, selected following a nationwide survey of\ud building stones carried out by a Government Select Committee. However, some of this stone began\ud to decay soon after construction in the mid 1800s. As the majority of the stonework has survived very\ud well the aim of the work was to source a demonstrably durable material with characteristics which\ud align with the majority of the existing stonework. Samples were taken from the building for\ud petrographic analysis in order to identify compatible material in quarries, either working or which\ud could be re-opened. Durability of the magnesian limestone was assessed using both accepted tests\ud and novel methodology. Large scale walls were constructed in the laboratory and exposed to\ud accelerated frost weathering with realistic temperature parameters. The logistical problems with\ud sourcing the original building material, the nature of the transport and the masons' unfamiliarity with\ud the stone may all have played a part in undermining its durability. When magnesian limestone is\ud properly selected and used correctly, its reputation for being of poor durability is largely unfounded.\ud Suitable sources for replacement stone were located which provided several options for both\ud immediate and long-term sourcing for repair and conservation.

During the second half of last century the forestry-wood chain has evolved and today ecosystem services in a sustainability framework are important. Forests are intended to provide services for the bio-economy, human health, biodiversity and climate control. An increased need for more renewable resources both for material and energy use has initiated extra interest for the potential to produce more lignocellulosic biomass, in short to increase wood production. One option is to provide in complementary production in planted forests. Both forestry and agriculture can take part in this. The cultivation of poplar hybrids in the temperate regions is a key option for the current and future bioeconomy. These fast-growing trees are producing lightweight hardwood with a low natural durability, but with an important potential as construction material especially as engineered wood products. All wood protection methods are of interest to be evaluated for this wood resource, making it suitable even for high quality applications. Poplar, for many reasons, has been nominated as hardwood with the best potential to perform similarly as softwoods for applications in wood construction. Benchmarking with wood species like spruce is relevant for several engineered wood products like plywood, LVL and even CLT. Wood treatments to increase durability have evolved from traditional wood preservation towards modification techniques such as thermally modified timber. Innovative poplar based products have been assessed on their performance and are designed to fit for purpose in relation to a specific combination of use class and service life. Introducing innovative poplar based construction product for green building requires adequate testing tools. Performance based assessment should allow to integrate different protective measures. Related to moisture dynamics and the linked fungal decay risk, opportunities to extend service life are manifold. Treatment can be differentiated e.g. for cladding (building envelope) and loadbearing construction components. Simple or sophisticated modification processes can alter the equilibrium moisture content. The use of wood based panels and new engineered wood products allow for better moisture control impacting fungal decay risk, but also alter the probability of insect damage. This paper intends to present several innovative poplar based construction products and show some cases of benchmarking in relation to an integrated service life approach.

The 5th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) reports important evolutions in the climate system. These changes are likely to affect the durability of the built environment. Although many contemporary studies investigate the future energy efficiency of buildings, research on the impact of climate change on the hygrothermal behaviour and degradation of building envelopes is rather scarce. Using climate projections, we studied the advantage of ‘hygrothermal response based‘ analyses over ‘climate based‘ analyses when assessing the impact climate change on facades. This paper presents a sensitivity study on solid masonry wall assemblies, before and after internal retrofitting, using three RCP (Representative Concentration Pathways) projections of the ALARO-0 Regional Climate Model at the grid point of Brussels (BE). The findings suggest the necessity of a ‘hygrothermal response based‘ analysis to study the sensitivity of the building envelope to climate change. Moreover, the largest sensitivity is observed for RCP 8.5, the scenario having the highest projected greenhouse gas concentrations by the end of the century.

Life-cycle management of urban road networks as a part of an urban system is a very complex process from the management standpoint of social, technical and economic aspects. The complexity and multidisciplinarity of such a problem suggest the need for using soft computing tools as well as multi-criteria analysis and group decision- making. Recently, there is a significant increase in using various soft computing tools, especially neural networks, for different prediction purposes in the field of road construction planning and management. Along with known advantages of such a prediction method, yet some applications showed the shortcomings. In that sense, the focus of this research is on possible applications of neural networks related to the life-cycle phases during the management of urban road projects. This is done in both horizontal (projects’ life-cycle phases) and vertical (hierarchical decision-making levels) approach. The final aim of the research is to compare and highlight the possible applications of neural networks as a prediction tool and support for decision-making in urban road management.

The Analytical Hierarchy Process (AHP) and PROMETHEE have gained increasing attention in the field of construction management as techniques for the analysis of complex situations and as decision support for decision makers. However, these two methods in themselves or their potential applications to problems of construction management are not sufficiently defined in the existing literature. The environment of group decision-making bring even more challenges. This paper consolidates and critically discusses the current knowledge on the application of AHP and PROMETHEE methods in the light of the specifics of the construction industry. A systematic literature review was used to select the contributions indexed in the databases Scopus and Web of Science. The findings indicate that the studies deal with broad topics and different aspects in different phases of civil engineering projects. This paper provides a useful reference work for researchers and practitioners interested in the application of AHP and PROMEETHEE as tools for group decision-making in civil engineering.

This paper introduces the ForestValue research project CLICKdesign – delivering fingertip knowledge to enable service life performance specification of wood. The consortium is working on a primary innovation to move from the complex, fragmented and general to the easy-to-use, consolidated and specific by provision of a digital tool for specifiers. Other materials tackle this and provide designers and architects with software. The specification of performance of wood products is complex and fraught with inconsistency and requires use of multiple platforms for data, experience, standards and national recommendations. CLICKdesign will provide a tool that has within it the decades of research, the complexity of the standards specification systems and the variation of approach due to tradition, materials and culture across Europe and beyond. A simple tool for nonexpert public users will be available as well as a tool accessible to professional users that will be refined with industry to ensure relevancy and accelerate uptake and use.

Chloride ingress in cracked concrete leads to rapid corrosion of embedded steel reinforcement and a decrease of the expected service life. Corrosion monitoring experiments showed that a 300 μm wide crack caused initiation of corrosion of a rebar (O 10 mm) with a concrete cover of 26 mm within three weeks of cyclic exposure to a 33 g/l NaCl solution. After a period of unstable corrosion activity during the first 20 weeks of exposure, corrosion propagated further at a relatively high rate (0.345 to 0.718 mm³/week). Application of a theoretical pitting model revealed that a reduction of about 50% of the rebar cross-section would occur after a period of 9 to 20 years of continuous cyclic exposure to chlorides. To avoid such rapid degradation, the use of self-healing concrete can be proposed. Introduction of macro-encapsulated polyurethane into the concrete matrix, will lead to the formation of a (partial) barrier against ingress of chlorides at the moment cracks appear. Corrosion monitoring experiments showed that the autonomous crack healing could not always prevent corrosion initiation, but caused an important reduction of the corrosion rate during the 44 weeks exposure period. The mean rate of volumetric loss of steel amounted to 0.042 mm³/week, about 15 times lower than for the untreated cracked samples. The rebars also showed no or very limited signs of corrosion after visual inspection. The simplified pitting model indicated that a 50% reduction in steel cross-section would take more than 5 times longer for samples with self-healing properties versus ordinary cracked samples.

Previously, only solutions with long-term experience were used in the building sector and it was sufficient to describe, e.g. in the building regulations, how they should be constructed. However, the innovation rate has gradually increased, encouraged by industrialization and by building regulations becoming more functional based. As a result, the required performance is often described for the whole building or for a building component, but not at product level. Furthermore, CE marking makes it possible to market and sell a product in any country within the European Union if only one or a few properties are declared, and these may even not be the most relevant ones for a specific application in a technical solution. A CE mark is therefore neither a quality mark nor an approval of the product for a specific application, although clients and consultants often believe this is the case. It is therefore a major challenge for the building sector to determine if a new building product is suitable in a specific technical solution (wall, roof, etc.). The paper identifies a gap between performance-based requirements for a technical solution and specific requirements to properties of building products. Two cases (flat roofs with no slope, MgO-containing boards used as wind barriers) show the possible economic consequences of not closing this gap; the technical solution failed, as one of the products was not suitable for Danish weather conditions. The first case initiated the formation of the Danish Building Defects Fund in 1986, the second one from 2015 shows that the gap still exits, 30 years later. The cases show how difficult it can be even for professionals to understand different certifications, especially when a product seems to be well suited for a specific use. Based on the cases, the paper presents a systematic approach that guides users through important issues relating to requirements for a moisture-safe building envelope. Previously, only solutions with long-term experience were used in the building sector and it was sufficient to describe, e.g. in the building regulations, how they should be constructed. However, the innovation rate has gradually increased, encouraged by industrialization and by building regulations becoming more functional based. As a result, the required performance is often described for the whole building or for a building component, but not at product level. Furthermore, CE marking makes it possible to market and sell a product in any country within the European Union if only one or a few properties are declared, and these may even not be the most relevant ones for a specific application in a technical solution. A CE mark is therefore neither a quality mark nor an approval of the product for a specific application, although clients and consultants often believe this is the case. It is therefore a major challenge for the building sector to determine if a new building product is suitable in a specific technical solution (wall, roof, etc.). The paper identifies a gap between performance-based requirements for a technical solution and specific requirements to properties of building products. Two cases (flat roofs with no slope, MgO-containing boards used as wind barriers) show the possible economic consequences of not closing this gap; the technical solution failed, as one of the products was not suitable for Danish weather conditions. The first case initiated the formation of the Danish Building Defects Fund in 1986, the second one from 2015 shows that the gap still exits, 30 years later. The cases show how difficult it can be even for professionals to understand different certifications, especially when a product seems to be well suited for a specific use. Based on the cases, the paper presents a systematic approach that guides users through important issues relating to requirements for a moisture-safe building envelope.

Woodframe construction is the most widespread building method. In Belgium the number of wood frame buildings has grown in the last years: in 2018over 10% of all new built dwellings were wood frame buildings. This increase can be partly attributed to the growing attention for energy performant buildings with a low environmental impact.In contrary to masonry construction, wood frame is more vulnerable to moisture problems, mould growth and wood rot. An important risk is water infiltrationthrough imperfections in the building envelope as a result of driving rain. Therefore it is important for the design to be resilientand allow drying without consequential damage.To analyze the drying potential, an experimental set-up with 8 wood frame compartments was built. The compartments differ in the type of insulation material (mineral wool or cellulose) and the type of vapour retarder (OSB or smart vapour retarder) that were used. In this way 4 types of compartments were obtained, each having a different combination of insulation and vapour retarder. Of each combination there are 2 identical compartments. This allowsto insert water in one of both, to mimic rain water infiltration from the outside into the compartment. Temperature, relative humidity and moisture content were measured on different locations in the construction (in total 92 sensors). In this way, the hygrothermal performance of the compartments with and without water infiltration can be analyzed, as well as the drying rate.

The lack of systematization in the collection of building defects leads to a wide range of data that is not used to its full potential. Unfortunately, this opportunity is missed since lessons could be drawn from analyzing this data by systematically mapping and investigating building defects. This paper presents the results of a statistical analysis on 27074 cases of building defects provided by a Belgian insurance company, ranging from 1991 up to 2019. This analysis focuses on the types of damage, the occurrence in relation to the construction time and the typology of the claims. Spearman correlation tests, X² tests, and Kruskal-Wallis tests are performed to assess the significance of correlations. Moisture problems constitute 49% of all technical defects, followed by structural issues (19%), and cracking (17%). Within the category of moisture problems, the roof is the dominant location for problems to occur, followed by basements, façades, windows, and rising damp. 50% of the judicial cases were closed after 3 years, whereas cases without lawsuit are typically settled after 1-2 years.

Concrete structures are subjected to shrinkage since the moment when the water makes contact with the cement. From that moment on, depending on the concrete composition and its curing conditions, chemical, autogenous and drying shrinkage might increase the risk of early-age cracking. Once a crack is formed, it may become the preferential path for the ingress of many aggressive agents inside the structure increasing the probability of damage due to corrosion, carbonation and other mechanisms. The use of superabsorbent polymers (SAPs) has been extensively studied to reduce the shrinkage cracking risk in mortar specimens by acting as internal curing agent to mitigate autogenous shrinkage. In this paper, a commercially available SAP was investigated as shrinkage reducing agent by means of internal curing in concrete specimens. The shrinkage of the concrete was monitored for 28 days with both a demountable mechanical strain gauge (DEMEC) and optical fiber sensors (SOFO). The SAP-containing concrete showed a complete mitigation of autogenous shrinkage during 28 days of measurement, for both methods. The SOFO sensors showed the occurrence of cracks after 7 days for the reference mixture, while for the SAP containing mixture, no crack was identified during the 28 days of measurements.

It is essential to create a comfortable and healthy indoor microclimate in order to assure proper conditions for work or recreation as people are spending 80-90% of their life in buildings. Therefore the building performance can help in achieving such sustainable living area, but also one should look into at other sources of temperature and humidity generators such as occupants’ habits. Based on gathered data from observed apartments an insight into preliminary analysis of indoor temperatures and humidity in urban social housing is given. The analysis of the results confirm the set hypotheses that the occupants’ habit significantly influence the indoor temperatures and humidity in urban social housing.

Cost prediction in early stages of construction projects is one of the crucial problems of project planning. Previous research has been directed to process based and data driven model development by using various techniques, e.g. regression analysis, support vector machine (SVM), neural networks etc. According to the research results, neither one of the techniques could be considered the best for all circumstances. Therefore, the research has been redirected towards the hybrid modelling, i.e. combination of different techniques. In this research, for prediction of the target variable – real construction cost of road structures, using available variables: contracted construction cost, contracted construction time and real construction time and cost, hybrid model – combination of SVM technique (data- driven model) and Bromilow time-cost model (TCM) (process-based model) has been used. Five hybrid models have been built for comparison purposes: SVM-Bromilow TCM, LR-Bromilow TCM, RBFNN-Bromilow TCM, MLP-Bromilow TCM and GRNN- Bromilow TCM, combining Bromilow TCM with SVM, LR (linear regression), RBFNN (radial basis neural network), MLP (Multilayer perceptron) and GRNN (general regression neural network), respectively. The best accuracy has been obtained with SVM-Bromilow TCM with mean absolute percentage error (MAPE) 1.01% and coefficient of determination (R2) 97.61%.

The paper presents the relation between the planned duration and costs for a project of reconstructing an overage public structure to become a public facility with social purpose. The aim of the paper was development of a management model for such projects so that they could be successfully carried out in terms of cost and time. The selected example presents the methodology of time and cost relation in the project. The selected tool for connecting the mentioned project parameters is the S- curve. The S-curve is obtained through the planning process in several steps which include creation of project WBS (work breakdown structure), cost estimate and progress chart (Gantt chart). The obtained S- curve is the basis which later serves as the indicator for project performance success. Aberrations from the planned values can be detected by comparisons, monitoring and control which enables duly reaction and undertaking specific correction measures. A quick information about key trends of the project and effects of specific decisions and measures on project cost and duration is obtained. The developed model can be applied to projects of reconstructing and reallocating public structures into public facilities with social purpose with similar technical and functional characteristics such as: size of the surface, number of floors, construction type, purpose and other.

The approach to the problem of wastewater treatment considering the size of the settlement is the following: settlements are grouped according to size - number of inhabitants, therefore it is a grouping according to the amount of water that settlements consume. The type of the wastewater treatment process is conceived in comparison to the size of the settlement. It will start from the large settlements (there are calculated settlements with over 20, 000 inhabitants), followed by purification processes for smaller settlements (5, 000 to 20, 000 inhabitants), and at the end solutions for processes of wastewater treatment in small settlements (less than 5, 000 inhabitants) will be considered. Wastewater from large settlements is usually processed in a centralized wastewater treatment plant. As for the treatment of wastewater from other settlements that we're not covering with an existing wastewater treatment plant, these settlements are using the following types: pre- treatment, primary treatment, secondary treatment, and tertiary treatment. For the group of the smallest settlements, up to 1, 000 inhabitants, a solution for wastewater treatment in these settlements should be sought through the implementation of large septic tanks, combined with subsequent purification of effluents from such tanks, such as sand-gravel filters. Natural treatment systems are recommended for the treatment of wastewater from small settlements (less than 500 inhabitants).

Buildings constructed several decades ago do not meet the energy efficiency requirements of current legislation and therefore needlessly consume great amounts of energy for heating. Most often their energy performance is improved by applying additional thermal insulation layers on buildings external walls. Research presented in this paper analyses construction technologies of various thermal insulation types and corresponding time needed for work execution and related costs. Economic analysis of proposed thermal insulation materials in this study is done by using the simple payback period. This paper presents a systematic approach for optimization of insulation material type and thickness. The optimization is based on implementation costs and time required for construction works. This case study is done by using database obtained from several single family houses in Croatia which have undergone a process of energy certification and which currently do not have insulation layers on their external walls. Two insulation materials are considered in this study, rock wool and polystyrene insulation and various thickness of those insulation. Research results presented in this paper can be useful in the selection of thermal insulation material and insulation thickness when considering not only buildings energy efficiency improvements but also time spent for applying insulation layer on external walls and cost effectiveness of selected insulation.

Recent development of the University of Rijeka campus area affects the quality of life (QoL) of the entire city of Rijeka population, especially student population, which comprises 13% of the city’s total population. During Campus First Development Phase (2008-2011), four faculties found their place in the campus area with no student accommodation nearby. However, in the fall of 2016, during the Second Development Phase, which began in 2015, the first on-campus-accommodations will be provided to students. Technical and economic aspects are the core during investment planning and decision-making processes, while the user requirements are rarely taken into consideration from the actual end-user, resulting in superficial implementation in developing processes. The aim of this paper is to identify the most important indicators influencing the students' QoL in the city of Rijeka and to give an insight of student needs as an input for better investment planning and modelling of urban areas according to their needs. Using a web-based questionnaire as well as personal questioning, the data were collected, analyzed, and compared across four groups of variables (accommodation, faculty location, food and beverages, and out-of- curriculum activities). The conducted research gives a preliminary insight into the students' points of view, thus giving the decision-makers a necessary tool for making more student- oriented decisions in the future campus development phases as a long-term developing processes in the urban area management.

Construction time is an element of every construction contract. Thus, its prediction is of particular interest. This paper presents a construction time prediction model by using General Regression Neural Network. Key data on a total of 70 constructed buildings have been collected through field studies. Chief engineers of construction companies have been interviewed on contractual and actually incurred construction times, contractual and actual construction costs, type of facilities and construction year. General Regression Neural Network (GRNN) from predictive modelling software named DTREG, as new approach in forecasting, was used for building the predictive model to predict the real construction time. Prediction was very accurate with mean absolute percentage error, MAPE, around 2.19 which means that the error of the model is around 2.19%, the coefficient of correlation between the actual and the predicted values is very high, r = 0.99 (rounded) and the coefficient of determination which measures the global fit of the model R2 is 0.97875 (or 97.88%). This paper contributes to and can be useful for the decision process on planning the construction time in construction companies and in the construction industry in general.

The aim of this paper is to establish a framework to explore how stakeholders influence megaprojects using the paradigm of sustainability. The paper begins by reviewing the literature concerning stakeholders and sustainability in megaprojects. It then critically reflects on two frameworks that have been developed to map sustainability in megaprojects and examines their utility in understanding stakeholder impact in megaprojects. The paper concludes by proposing a framework based on sustainability and the results of this analysis whereby the interactions of megaprojects with stakeholders can be evaluated.

The main goal of this paper was to compare the application of a budget and a PPP model in financing public standard structures in post- transition environment. The analysis was conducted on education and sports facilities by applying the multiple-case study. The research and analysis of numerous public construction projects which were carried out in transition and post-transition social circumstances has shown the occurrence of characteristic risks. The trend in the Republic of Croatia indicates an even more intensive interest of the state for financing the public facilities by using the private capital. The progress and condition prognosis of future PPP projects in post- transition economies points out a possible occurrence of several of previously recognized characteristic risks. Those are risks which, although allocated on the private partner, can have a negative effect on the public partner as well.

Due to everyday burst of technological developments and their application in the field of project management, there is a lasting need for improvement in student teaching and assessment processes. Such place where engineering students can be challenged both creatively and by knowledge in complex project environment can be found in the graduate study programme under the course of Project Management at the Faculty of Civil Engineering in Rijeka. As one of the course objectives is active work on actual project proposals, students are divided into supervised teams. Each team is responsible for the development of one project scenario for the Project Delta in the city of Rijeka, and is evaluated as the best project proposal among defined project teams and their proposals. Prioritization of project proposals deals with complex decision making. It is characterized by lots of participants, multidisciplinarity, huge quantities of information, limited budget, conflict goals, and criteria. In order to cope with such complexity and to help professors during decision making processes, this paper proposes the use of multi-criteria methods for solving priority setting problem. The starting point in this methodology is goal analysis and development of adequate criteria set. Evaluation of criteria importance is based on a set of experts’ opinions processed by AHP method, while all data processing is done by PROMETHEE multi-criteria methods. The end result is a priority list of student project proposals. By presented methodology specialized software is introduced into education process of construction management, thus innovating curriculum and assessment of the course.

Implementation of the Water Framework Directive is a key starting point for integrated river basin management. Lack of sanitation in communities less then 2000 PE combined with agricultural activities, represent a special challenge for national water quality management. Sanitation for agglomerations smaller than 2000 PE and rural areas represent a big source of organic pollution not tackeled by EU legislation, and a threat for achieving good status for all water bodies and environmental objectives of the river basin. Moreover, some countries like Croatia and Slovenia comprise a large area of agglomerations smaller than 2000 PE. Proper management of thoose areas is crutial for preserving water resources as well as biodiversity. This paper will analyze some experiences related to management of rural areas using the DPSIR (Driving Forces - Pressures - State – Impact - Response) approach taking into account the principles of sustainability. Successful management of rural areas includes a variety of measures ranging from expensive sanitation of point and diffuse sources of pollution to low-cost solutions for pollution prevention of water bodies. The usage of the appropriate mathematical models, can assist in responding to environmental impact assessment and the optimizaton of the measures. In this paper will be presented the preliminary analysis of the mathematical models, as their applied and limiting possibilities, for water quality management of the river basin. In most cases those models need to be adapted or upgraded according to specific needs. The preliminary selection of the appropriate model for one river basin, that is Sutla basin, will be presented.

Current construction codes and standards determine minimal infrastructure, financial and human resource indicators for realization and development of primary education. Disproportion that appears in construction practice directs to the need for establishing upper, maximum values indicators. The need for indicators is pointed out by the government of Republic of Croatia in its “General program for construction and reconstruction of public facilities according to public-private partnership” from 2012. The main goal of this paper is to present database of standards for construction, maintenance and utilization of educational system facilities in the Republic of Croatia. Beside the quantitative indicators, it is necessary to define certain qualitative indicators (in term of various technical solutions, materials and other) that would lead to more rational solutions and improved management of government budget. Database is organized in a table form, with technical, functional and quality indicators arranged in groups. Established database contributes to definition of the acceptable construction problem solutions for educational system facilities.

Planning, design and implementation of traffic infrastructure is a complex task especially when it is done for infrastructure located in urban areas because it depends on different factors and interests. This is why the solutions have to be evaluated by different type of criteria (traffic, economic, environmental and social). For this purpose during last decades multi-criteria methods came into use and numerous methods have been developed which are classified as multi-criteria analysis methods (e.g. PROMETHEE, ELECTRE, AHP). In this paper the overview of how the multi-criteria analysis method AHP - Analytic Hierarchy Process is used as decision making tool in the process of transportation planning is given. AHP has been used for analysing different types of problems in the field of transportation engineering: selection of routes for railways, roads, bicycle, metro-lines, and selection of priorities of construction for transportation objects. In the paper the case study in which AHP is used for defining priorities in planning multi-store garages is described. In this case five different locations using four main criteria and eight sub-criteria were evaluated with AHP method. The results show that AHP can be used for evaluation of location for transport facilities and that the AHP methodology can be easily implemented in transportation infrastructure planning. It gives the possibility to make decisions using a larger number of criteria, enables the pair-wise comparison of alternatives and enables the involvement of all interested parties.

New market laws impose new project delivery methods in order of greater efficiency. Design and Build can certainly be regarded as one of most common in this context. Although worldwide proven, Design and Build has not yet taken hold on the slowly-changing construction market of The southern east Europe (SEE). The main aim of the this research was to collect data that will indicate the presence and previous experiences in applying Design and Build models of procurement in the construction Croatian market, or market awareness of alternative methods of project delivery as well as the possibility of implementation of this model in the Croatian construction industry. Among other things, the research was to examine the general opinion on the Design and Build procurement model by profession, specifically investors, design/supervision and contractors separately, to give a realistic insight into the perspective of different participants in the construction. We have found that neither half of respondents is familiar with Design and Build project delivery method, and only one third of subjects did participated in that kind of projects. Most important conclusion is that 89% procent of respondents who participated on Design and Build projects think that model is applicable in Croatian construction industry in comparison to only 37% of total sample who has shared the same oppinion.

The river Sutla (Sotla) forms the border between the Republic of Slovenia and Republic of Croatia. The Sutla Lake (Vonarje reservoir) of 12.4 million m3 was built and filled in 1980 as drinking water supply and for flood protection. Immediately after filling, the reservoir showed extreme water quality problems, degradation of the water use. Due to high risk for the humans and the environment that has hardly been managed successfully, the reservoir was drained in 1988. Now it operates as a dry retention basin for flood protection. Over the past decade, the area of the Sutla catchment has developed touristically. Nowadays, there are many local and regional initiatives to fill the Sutla Lake with water again and to build tourist and recreational facilities. There are also initiatives to use water for irrigation and as a drinking water supply. All of the stated facts indicate an urgent necessity to improve the water quality of the river Sutla and to redefine the Sutla Lake as a multipurpose lake. We propose a conceptual framework for water quality management and design of the mathematical model for the river Sutla water quality with emphasis on the Sutla Lake.