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Geodynamic natural phenomena, such as landslides and earthquakes, are among the most hazardous natural threats to human lives and property. Usual landslide triggers are floods and heavy rainfall, in which case speed of onset is mostly rapid and damage to structures and systems can be severe (buildings may be buried or villages swept away). In addition, transportation networks, with embankment and cutting slopes, retaining structures, bridges, and tunnels as their integral parts, are considered to be of paramount importance when the risk under strong earthquakes is considered, since accessibility of roads affects the speed and the scope of the emergency measures to be provided in the very immediate post-earthquake emergency and relief operations, and since the earthquake-induced damages to the infrastructures could severely affect the economy of a region due to the time required to restore the functionality of the network. Prevention measures and activities are the best mean of protection of human lives and social goods. Natural disaster prevention arrangements are of long-term character with permanent governmental and professional activity for the needs of establishment of consistent scientific bases and their practical application in prevention and mitigation of disaster risk. In this respect, the contemporary tools in prevention of landslide occurrence, as well as in reduction of seismic risk for foundation structures and, in particular, for tunnel structures as crucial elements in transportation network, are presented in this chapter, with a special emphasis on the state-of-the-art hazard analysis, geotechnical and construction strategies of prevention and mitigation of adverse natural hazard effects, as well as on development of monitoring and early-warning systems.

Finite element analysis (FEA) and engineering software is increasingly used in modelling of different structures and in analyzing their behaviour. The subject of this paper was an analysis of behaviour of reinforced concrete column footing laid on deformable subgrade and loaded by concentrated load until failure. The modelling and 3D nonlinear analysis were implemented by applying finite element method (FEM) and using software package ANSYS 14.5. Field test data were used for calibration of the FE model and validation of the adopted parameters for all materials. The comparison of the field test results and FEA results showed good agreement, but also revealed some questions regarding FEA, and especially concrete crushing.

Reduction of the energy consumption without compromising living standard has become very important issue in architecture, civil engineering and building industry. This problem includes numerous independent and often contradictory aspects. That indicates that a compromise between construction cost and energy efficiency should be found. The study presented in this paper has shown that choice of structural system and its elements can significantly influence the total price of a building as well its environmental impact. Since these two aspects are usually directly confronted, the decision-maker should be aware of all their advantages and disadvantages. Therefore, numerical analysis for exploring different possibilities should not be exclusive, i.e. not to provide only one solution, but to offer at least several solutions in order to enable decision-maker to get a good insight and to make the most appropriate choice considering given situation. The methodology presented in this paper, based on multi-objective Big Bang – Big Crunch algorithm, has proven to be successful in solving this kind of problem.

In construction practice it is often possible to replace the building material, which is planned in the design phase, by the local cheaper material. In this paper analysis of the possibility of replacing the retaining structure of reinforced earth, which is envisioned in the main design of the Highway E-80: Nis – Dimitrovgrad, by embankment of disintegrated rocky material, is presented. This material is obtained by blasting the rock mass near this location. Recommendations for changing of the main design were given based on the results of the computational slope stability analysis which was performed by the limit equilibrium method, according to Spencer's solution. Due to this change the organization of construction works is significantly improved.

Reinforced concrete diaphragms are in-built supporting structures constructed directly in the ground. They are intended for reception of lateral soil pressures, and due to the thickness-height ratio they belong to the group of deformable structures. The paper presents different design methods of transversally loaded diaphragms as well as constitutive soil models which can be used on this occasion. For comparison of the described methods, one example of design of reinforced-concrete diaphragm with the analysis of obtained results was done. The diaphragm is firstly treated using classical analytical methods, and then using the numerical methods based on the concept of problem discretization using finite differences method and the STRESS, TOWER and PLAXIS software. The goal of the paper is as accurate prediction of the diaphragm and surrounding soil behavior as possible, as well as finding of the relevant impacts required for the design.

Concrete and reinforcement used for making of reinforced concrete foundations, can be exposed to different aggressive impacts of the environment. As a consequence, reinforced concrete material deteriorates in time. There is a number of methods, i.e. ways to prevent the damage of reinforced concrete foundations. In the paper are mentioned some of the methods such as: proper selection of foundation depth, construction of the gravel layer below the foundations, construction of the proper drainage and construction of adequate moist and water insulation, proper placing and curing of concrete. In additions, during design of concrete mixes, one must take into consideration the degree of exposure of concrete to the external impacts. In the design of the concrete mix, various admixtures are used, providing appropriate water-tightness of concrete and frost resistance. Also various coating chemical can be used as the additional protection of the concrete surface, such as: hydrophobic silicon impregnation chemical, epoxy resins, bitumen sealing strips or self-adhesive strips, bitumen emulsions, synthetic foils (membranes), hydro-insulation cement masses, bentonite barriers, studded foils (membranes) HDPE, bathtub –like structures... A special attention must be paid to the thickness of the protective layer of the concrete, as well as (when needed) to the choice of reinforcement resistant to corrosion.

In the course of their service period, concrete structures are exposed to a variety of impacts. A combination of exposure to aggressive effects, poorly constructed structural details, negligence of the durability issues, construction errors and underestimation of the importance of maintenance can lead to a severe damage of reinforced concrete which is used for construction of these structures. The reinforced concrete damage issues can be divided into the concrete damage and reinforcement damage. The paper provides some of the aggressive effects which can have impact on the reinforced concrete foundations, and which can be caused by soil, ground water or weather.

In contemporary construction practice is increasingly being applied flexible retaining structures of mechanically stabilized earth, gabions and precast elements. Although widely used only recently, their benefits are proven and widely accepted. The first part of the paper provides an overview of the possible ways of using of precast elements in the construction of retaining walls. The second part gives a detailed overview of the experimental testing of stability of retaining walls of prefabricated betonblok elements. The effect of static loads on the wall was examined in the first, and the effect of the dynamic loads in the second experiment. The results are analyzed and recommendations for future research are given.

The effects of soil–tunnel structure interaction are proved to be quite significant, particularly under earthquake excitation. The influence of earthquakes on a tunnel–ground interaction depends on the peak acceleration, the intensity and duration of the earthquake, and outmost on the relative rigidity between the tunnel and the ground. With an aim to study the effects of tunnel–ground interaction, two-dimensional simplified dynamic linear analyses have been undertaken using the finite element based commercial software ANSYS. The present study employs a continuous FE model in order to estimate the soil–structure interaction effects regarding tunnel structures under earthquake action, for the cases of both good and poor soil conditions. The earthquake loading is simulated under simple shear conditions obtained by means of a one-dimensional free-field site response analysis in the code EERA. The obtained numerical results are compared to the most frequently used analytical expressions, and by that, a capabi...

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 assumptions and basic equations of the first-order shear deformation plate theory of Mindlin, as one which provides more accurate solutions compared to the classical theory, are briefly presented in this paper. Application of one analytical solution derived according to this theory is presented by use of example of stress-state and deformations calculation of the reinforced concrete footing, which has been the object of recent author's experimental research. Numerical results obtained by applied procedure, which refer to the elastic domain of material behavior, are compared with experimentally obtained data of deflections of footing plate midpoint. .

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.

In this paper the possibility of using waste glass in road construction is discussed. Samples of clay material with the addition of waste glass were subjected to a series of laboratory geotechnical tests performed at the Laboratory of Geotechnics at the Faculty of Civil Engineering and Architecture in Nis. The obtained results were compared with criteria defined in the document ?General technical requirements for road construction?. On this basis, the conclusions on the suitability of this mixture for the intended purpose are given.

This paper presents the results of interlaboratory testing the grain-size distribution of sand and gravel on representative samples from the site of the western part of the Kostolac Basin. The results were statistically processed by two ways: Numerical method: the Cochran test of accuracy and Graphic interpretation: the MANDEL technique of consistency in accordance with the Standard SRPS ISO 5725-2 [1,2]. The followings were calculated: repeatability variance Sr2; interlaboratory variance SL 2 and reproducibility variance SR 2. Samples were submitted by sharing method to all participating laboratories.