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The University campuses represent a dominant type of organization of the living activities of students. Buildings and common features, were usually built, in a classical manner. This means that majority of the student living complexes was built in the massive and skeletal structural systems of concrete and steel. This paper deals with the possibilities, advantages and examples of an innovative structural system, named CLT or XLAM system. The XLAM system was developed in Germany around 12 years ago and it has been rapidly spreading in most European countries such as Austria, Switzerland, Italy and Nordic Countries. It is a European innovative timber based material in which timber boards, made of domestic timber species are assembled in layers and glued together crosswise in order to form massive timber wall and floor panels characterized by significant mechanical properties. Such type of structural system can serve as a models for construction of residential, commercial and student facilities in Serbia. [Projekat Ministarstva nauke Republike Srbije, br. TR 36037: Construction of Student hostels in Serbia at the beginning of 21st century]

Reinforced concrete (AB) is characterized by huge inhomogeneity resulting from the material characteristics of the concrete, then, quasi-brittle behavior during failure. These and other phenomena require the introduction of material nonlinearity in the modeling of reinforced concrete structures. This paper presents the modeling reinforced concrete in the software package ABAQUS. A brief theoretical overview is presented of methods such as: Concrete Damage Plasticity (CDP), Smeared Concrete Cracking (CSC), Cap Plasticity (CP) and Drucker-Prager model (DPM). We performed a nonlinear analysis of two-storey reinforced concrete frame by applying CDP method for modeling material nonlinearity of concrete. We have analyzed damage zones, crack propagation and loading-deflection ratio.

Lightweight constructions represent an economical alternative to traditional buildings, one of whose main drawbacks is the very high energy load needed to keep internal comfort conditions, as they are unable to curb rapid variations of temperature. When compared to heavier weight materials buildings, it is estimated that to maintain a thermally comfortable temperature range of 18-24°C, low weight materials use between 2 and 3 times the heating and cooling energy needed by a heavy weight material construction. The research concept is based upon the fact that outdoor/indoor heat exchanges (which play a significant part of lightweight buildings cooling and heating loads) can be potentially controlled by a new fiber insulation that possesses a thermally active heat storage capacity. During the day, when temperature rises, the peak loads can be largely absorbed by a PCM (Phase Change Material) - enhanced fiber insulation layer, only to be slowly discharged back to the environment later (during the night time, when outside temperature drops), without affecting the interior building energy balance, as it is aided by the presence of an standard low heat transfer fiber insulation layer. This approach will provide a much slower response of the building envelope to daily temperature fluctuations, helping in maintaining inside temperature in a comfortable range and thus avoiding the need for extra energy consumptions to accomplish it. Effective levels of indoor comfort will be also guaranteed by the well known fiber materials excellence, when it comes to reduce airborne noise transmission and its superior performance upon controlling the sound resonance in construction cavities. Development of such material is in final phase in frame of European FP7 project STOREPET (FP7-SME-2011-2, Proposal 286730). Project participant from SEE is Construction Cluster „Dundjer” from Niš. Development and application of project results will be presented in this paper. [Projekat Ministarstva nauke Republike Srbije, br. III44006 i br. TR37003 i EU FP7 project STOREPET (FP7-SME-2011-2, Proposal 286730)]

The process of building an object consists of planning, design, construction, use and eventual demolition [1]. In each of these components in the process of building uncertainties occurs, which can be caused by human or natural effect. Human cause of uncertainties includes intentional and unintentional deviation from the optimal realization, the use of inappropriate materials, unverified construction methods, poor quality of connections between elements, changes to the building design without the consent of all parties. Natural effects are often unpredictable. Reliability is the ability of the structure to meet the construction requirements set out under specific conditions during the service life, according which it is designed to [2]. It refers to the carrying capacity, serviceability and durability of construction and according to them different degrees of reliability can be defined. One of the best ways of presenting the size of the uncertainty in the theory of reliability is the reliability index β.

In contemporary design, vehicle impact into the structures is paid great attention since they can be dominant, depending on the type of structure. The key issue in the vehicle impact analysis is the proper determination of intensity and way of action of dynamic forces on the structural element and its behavior after the imparted load. The Eurocodes, in the annexes provide recommendations for determination of force intensity depending on mass and velocity of the colliding vehicle. Equivalent static loads causing approximate effects on the structural elements are used as quite approximate and efficient methods. The paper comprises the analysis of deformation of columns having the same characteristics, exposed to impact loads via the equivalent static loads, depending on the stress state in columns, and a comparative analysis has been done.

The construction of energy efficient buildings using innovative building materials such as phase change materials, in addition to improving indoor comfort, energy savings and costs, can be achieved by increasing their market value. Because of its ability to absorb and release energy at predictable temperatures, phase change materials are effective in controlling and maintaining the thermal environment in the building. The use of phase changing materials, materials stored latent energy storage is an effective form of heat. [Projekat Ministarstva nauke Republike Srbije, br. TR36016: Experimental and theoretical investigation of frames and plates with semi-rigid connections from the view of the second order theory and stability analysis]

Various factors are taken as the criteria for determining the susceptibility of materials to frost, such as: porosity and water absorption, volume changes, the number of freezing and thawing cycles. Mortars as a mixture of binder, water and sand, after placing and undergoing bonding and solidification processes, represent extremely porous materials, and the same holds for concrete. When the water turns into ice, it changes its volume measure unit from (Vω) into Vt = 1.09 Vω. If the concrete that has not completed bonding is exposed to frost, the process is likely to be suspended, and later when the warming starts, followed by the thawing of concrete, it will need the repeated vibrating in order to bind again and harden up without the detrimental effects on its strength. However, there are cases of devastating effects of frost on the hardened concrete. All the mentioned strategies should be kept in mind when performing remediation.

Geotechnical performance of 'soil-structure' systems is strongly dependent on the properties of the soil and prediction of the performance of these systems in real conditions requires accurate modeling of soil parameters. With the help of high-speed computers, now it is possible to create advanced constitutive models, but large uncertainties and variations in soil properties could reduce the advantages gained by using such models. In this paper sources and types of uncertainty in geotechnical engineering practice are first presented, followed by a review of the basic concepts and terminology of geostatistics. Finally, procedures for quantification of uncertainty and for geostatistical estimation and simulation of spatially variable soil properties are presented.

The paper presents a brief description of experiment within the research project 'Theoretical and experimental analysis of interaction of shallow reinforced concrete foundations and soil for the purpose of improvement of national regulations and implementaation of Eurocode system' where in situ tests of a series of reinforced concrete foundation footing were performed, by loading until failure. As a rule, methods for calculation of shallow foundations settlement on granular soils overestimate the expected settlement, and underestimate soil bearing capacity, which results in a conservative foundation design. In order to test accuracy and reliability of the different settlements prediction methods, a comparative analysis of settlements calculated using these methods and those measured during experiment, was performed.

The problem presented in this paper has been treated intensively by various researchers. However, considering that by its nature the problem of structure stability belongs to the area of nonlinear analysis, it represents an inexhaustible source for investigations. Thus, we propose a simple method to determine the elements of geometrical matrix of member rigidity by energetic method through finite element method.

DYNET Project has greatly contributed to the development of high engineering education at the University of Niš, since year 2000. This project has been financed by the German DAAD program, in the framework of the South East Europe Stability Pact, and the goal of the project is primarily development of high education in the region, and education of young engineers. The project began at the Ruhr University of Bochum (RUB) in cooperation with the Universities of Niš (UN), Skopje and Sarajevo, and later expanded to other universities. The basis of cooperation is a very successful long term cooperation of two universities of RUB and UN, that dates back to 1975 and which has been managed by professor Guenther Schmid of the University of Bochum. A reform of the Curriculum was initiated at the Faculty of Civil Engineering and Architecture of Niš in 2000 and it has been officially underway for three years. The programs have been organized along the principles of the Bologna process. The studies are divided into three levels: Bachelor Studies, Master Studies, and Doctoral Studies. The programs of the studies comprise study fields such as bridges, tunnels, hydraulic engineering, road and rail networks or residential, commercial and industrial buildings. The paper promotes the benefits of the participation of the Faculty of Civil Engineering and Architecture of the University of Niš in the DYNET project, as well as the analysis and challenges which were present in the process of engineering education.

This work presents preliminary design of the road bridge made of laminated timber. The supporting system of the main bearing elements is made of the laminated timber in the system of arch with three joints; the bridge slab is designed as continuous slab, made of nine equal fields; each pair is made as composite timber-concrete beam, where the road slab is made of concrete and the needle pieces are made of timber. Fundament is based on HW piles. All the elements are designed to Eurocode.

The paper presents the conceptual design of the footbridge made of laminated wood. The supporting system of the main bearing elements is made of the laminated wood in the system of arch with three joints and the bridge deck is made of the composite timber concrete structure system. The load patterns for which the dimensions of the supporting bridge structures were adopted (verified according to Eurocode) are presented.

This work deals with composite timber concrete structures. By combining timber and concrete in new type of composite material and using the best properties both materials, the high tensile strength of a timber and the high compressive strength of a concrete, depending of different building conditions we can find a lot o reasons for decision to apply this type of the structure in comparison to concrete or steel structure. Here, design methods and procedures for determination of load bearing capacity bar shaped connectors (fasteners) very often used as element connecting timber and concrete in composite structures will be given. The procedure will be exposed and explained according to the new fashioned methods collected as set of Euro-norms in Eurocode 5. The design equations in Eurocode 5 derived from Johansen's work are based on a rigid plastic behavior of the fastener under bending moments and the timber under embedding stresses and take into account the plastic moment capacity of the fastener.

In modern timber structures a large number of beams are loaded with bending Contemporary engineering practice has shown that the effect of tangential stress and deflection of beams are not controlled during the design of this kind of beams. This could produce negative consequences in structure behavior during the exploitation. Using optimal design procedure in this article, the member is designed for bending in two planes. The following criteria must be observed: normal bending stress, shear stress and maximal deflection.

This paper deals with a general state of European norms for timber structures, according to "Eurocode 5: Design of timber structures, part 1.1 General rules and rules for buildings ", together with the following European norms EN. The concept of design of timber structures, according to limit states and Eurocode 5 (EC5). draft is briefly shown. In some areas a comparative analysis of EC5/JUS/DIN norm is given. The paper contains the proposition of the possible model for limit state of rupture of the timber structures during bending and eccentric stress.

This paper deals with the composite timber-concrete structures. By combining timber and concrete in a new type of composite material and using the best properties of both materials (the high tensile strength of timber and the high compressive strength of concrete) a new type of composite structure is obtained, which can have many applications, depending on the different building conditions, due to the certain advantages it has over concrete or steel structures. Here, the design procedures according to the theory of elasticity based on the exact method and approximate method are given in order, and particularly according to the regulations and recommendations of the modern concept for design of timber structures and concrete structures given in Eurocode 5 and based on the limit states of bearing capacity and usability of structures.

Tins paper deals with Serbian higher education, especially in engineering, and with modern tendencies in the globalization of European engineering education based on Bologna Declaration. The main goal of this paper is to explain the existing system of engineering education in the Republic of Serbia: Scientific Universities with different Technical Faculties and Higher vocational technical schools. History of engineering education in the Republic of Serbia from the first Engineering Schools in 1846, then the Technical Faculty of Great School in 1863 and finally the University in 1905 will he presented as well as a comparative analysis of other relevant Universities (Technical) in Europe. Special focus will be done on the present state of affairs in the above-mentioned education with concrete measures for improvement of engineering education according to the actual European tendency. At the same time a necessity and a need for rapid, rational and efficient reforms and restructuring of Serbian higher education, especially in organizational, financial and educational domain, will be discussed.

Abstract: This paper presents an experimental–numerical analysis of damage localization of concrete plate‐like elements on the basis of hybrid approach. The proposed hybrid approach uses the fast discrete wavelet transform, energy approach, and time of flight criterion for the purpose of localization of single and multidamage problems inside or on the periphery of concrete elements. Verification of the proposed damage localization approach has been performed under laboratory conditions using a laser scanning‐based system with piezoelectric excitation of the wave propagation. Numerical simulation of the wave propagation is performed using the explicit finite element method using 3D models with linear‐elastic material model of concrete with Rayleigh damping. The Rayleigh damping coefficients are determined on the basis of experimental data and implemented in numerical models. Validation of the numerical model is conducted, based on the comparison with sensor output signals obtained through experimental measuring and a very good agreement of results is obtained. The proposed hybrid approach to damage localization is verified using 15 different models/specimens, varying the number, shape (circular or notched), and position of damage, as well as the number and placement of actuators/sensors. For all the analyzed scenarios, the hybrid approach successfully localized the damage even for the least number of used sensor positions. In the models with the circular damage, the damage image created on the basis of the hybrid approach is almost identical to the actual shape of the damage, indicating a good potential of the method for damage localization. [ABSTRACT FROM AUTHOR]

A timber-concrete composite system is increasing the use of timber in construction. Some structures cannot be built by timber alone, but this type of composite system makes it a possibility. The deterioration of structures in service is generally uncertain over time. The appropriate approach therefore for a structural analysis is a time-dependent reliability analysis which considers the randomness and uncertainties of the deterioration process over a specific time period. This paper describes two methods for time-dependent reliability analysis, a random variable deterioration rate model and a gamma process deterioration model. It also, compares the deterioration prediction as well as service life estimation of timber-concrete composite beams under normal use, based on proposed models. [ABSTRACT FROM AUTHOR]