Durability of Critical Infrastructure, Monitoring and Testing

Frontmatter

Study of the Internal Structure of Isotropic Pyrolytic Graphite by Broadband Ultrasonic Spectroscopy

Abstract

As material for structural components, isotropic pyrolytic graphite (IPG) is widely used in such objects of critical infrastructure as nuclear fission reactors. There is the possibility of using IPG as a facing material for experimental thermonuclear facilities; this is currently being explored. Also, IPG is used as a sealing and anti-friction material in the aerospace industry. It is shown that X-ray tomography is not very suitable for studying the internal structure of IPG produced by chemical vapor deposition because its density is much the same as that of heterogeneities encountered in IPG, such as carbon black inclusions and anisotropic pyrographite crystallites. Broadband ultrasonic spectroscopy has been used to detect pores and carbon deposited layers in IPG samples, 2D images of the internal structure produced.

Anton S. Bychkov, Elena B. Cherepetskaya, Adam Konvalinka, Alexander A. Karabutov, Alexander Kravcov, V. A. Makarov, Elena A. Mironova, Nikolay A. Morozov

Assessment of Protective Structures on the Basis of Their Acceleration Caused by Blast Wave

Abstract

The purpose this study was to assess the protective structures of different shapes on the basis of their acceleration caused by blast wave. Six variants of models was assessed in the software environment Ansys Autodyn, an explicit tool for modelling the nonlinear dynamics of solids, fluids, gases and their interactions, where the compared parameter was the value of the acceleration of the structures loaded with blast wave. This study represent the second step in the search for optimal shape of protective structure with regard to limitations such as building materials on the base of concrete, low manufacturing cost, modularity and easy transportability and follows the conclusions from the study [11].

Jiří Štoller, Branislav Dubec

The Possible Means Suggested for Improvement of Evaluation of Low Endurable Terrain

Abstract

This article deals with the improvement of means for evaluation the trafficability of terrain in the frame of the Engineer Corps of the Czech Army. There are described the most used instruments the telescopic penetrometer PT-45 used in the Czech Army and the cone penetrometer from the Trafficability Test Set used by some NATO countries. There is written about problems the Engineer Corps has to face. It means that there are not enough instruments. The second weakness for the proper evaluation of the trafficability of terrain is the lack of materials for working with these instruments. So the steps making for removing these problems described here.

Klára Cibulova, Matouš Formanek, Martin Priesner

Neural Networks in Back Analysis of Tunnels

Abstract

To ensure the best agreement of the numerical model behaviour and the reality the back analysis can be used. At present, the engineers prefer relatively simple back inverse methods, however it does not necessarily lead to the desired results. Between the current methods to perform back analysis of soil parameters the method based on the artificial neural networks is the one which is used in the Czech Republic. After a short introduction the principles of the prediction of the tunnel deformation using multi-layer neural network with back propagation are described. At the end of the paper the practical application of the neural networks in the back analysis is shown.

Pruška Jan

Some Design Considerations of a Fire Within a Sub-surface Railway Switches and Crossings

Abstract

This study was performed to assess the event of a fire on a train within the S&C area, addressing the limiting of smoke flowing into either the adjacent station or the tunnels. Both areas of infrastructure had to be protected as they could be occupied by people either at the station or in trains, as well as being potentially part of the evacuation route for occupants of the S&C area. By the very nature of the S&C, the evacuation of passengers within this area also posed an issue due to the routes to safety, which are not easily protected in such a relative large enclosed space. The access routes for fire brigade and the firefighting environment were also considered. The following briefly outlines the application of two fire engineering toolbox techniques; CFD smoke modelling and evacuation analysis. These tools provide important components required to perform an ASET and RSET assessment, which can provide powerful insight into the ability of passengers to escape. By constructing a 3D CFD model and measuring key parameters with respect to time, the tenability along the potential escape routes was considered. Combining this data with a travel time assessment of the evacuating passengers informed the performance-based approach to develop an optimum and specific ventilation and evacuation strategy. These in turn allow for guidance to be developed on the training and management requirements, which are to form part of the overall system’s operational emergency procedures. It also addressed the considerations for the access provisions for the fire brigade.

Aaron McDaid, Nicole Hoffmann

Replacement of Permanent Bridges After Floods in 2013

Abstract

The paper deals about operation of Czech Army Engineer Corps in year 2013. There were three units of Czech Army participate in this operation. University of Defence, Military Geodetical and Hydrometeorological Office and 15 Engineer Brigade.

The aim of this operation was to construct temporary bridge after flood. During this operation was used REACH-BACK concept between University of Defence and Geodetical and Hydrometeorological Office and between University of Defence and 15 Engineer Brigade. Communication and cooperation between these units was supported by Information portal of engineer corps. The portal works as a support element for REACH-BACK concept.

Martin Benda

On Utility Assessment of Building Projects

Abstract

The paper describes the methodology of computer modeling of the building process of projects with utility assessment and the main principles of the integrated cost estimation, project management and quality assurance microcomputer based system developed recently. This expert system is based on quick modeling of the building process by use of typical construction technology network diagrams, which can be prepared in advance. The typical network diagrams can be modified according to the spatial conditions of a certain building and to the amount of construction works and materials. For utility assessment a vector of 10 main aspects (criteria) was created with a common measure unit and certain level of importance each. A database of construction processes was created including the aspects for utility assessment. Thus, the model of the building process can be made about 50 times quicker than by current project management systems and it can be used for bidding, project planning and management and utility assessment.

Čeněk Jarský

Design Tool for Static Design and Evaluation of Steel, Wood, Concrete and Masonry Members in Buildings

Abstract

This paper is focused on the creation of the series of design tools for design and assessment of individual construction elements made of steel, wood, concrete and masonry. These design tools are created as the individual files in Mathcad and are accompanied by the flowchart with computing algorithm. All proposals are performed in accordance with the EU standards.

Jan Holub, Pavel Maňas

Measurement of Residual Stresses in Alloys Using Broadband Ultrasonic Structuroscopy

Abstract

Broadband ultrasonic spectroscopy used to measure residual stresses in samples of high-temperature alloys. It is shown that the acoustoelasticity method and laser ultrasonic spectroscopy can be used to determine the depth distribution of residual stresses. Measurements were carried out on test samples of heat-resistant nickel-base and titanium-base alloys with specified distribution of residual stresses after vacuum heat treatment, vibratory stress relief or shot peening. The results were compared with the residual stresses determined from changes in the deformation upon the removal of layers from the sample by electrochemical etching.

Alexander A. Karabutov, Elena B. Cherepetskaya, Alexander Kravtsov, Vladimir A. Makarov, Elena A. Mironova, Dmitry V. Morozov, Pavel Svoboda

Mathematical Formulation of Innovation of Production Process

Abstract

The article is a proposal of development of anhydrite screed and subsequently carrying out samples of examination of anhydrite screed without fibres and with different kinds of fibres. Furthermore, there are mentioned determination and comparison of mechanical as well as physical characteristics of those different samples. There have been performed calculations of critical point of proliferation of breach by means of fracture energy and cross-cutting module for validation of differences between proliferation breaches of anhydrite fry with and without fibres. Based on the comparison of both results there have been determined different criteria for proliferation of breach for firmness in bending tension and for linear fracture mechanics.

Popenková Miloslava

The Influence of Subsoil on Electromagnetic Detection

Abstract

Decommissioning of exercise ranges reflects downsizing of Czech Army. That process (started in 1993) requires disposal of all remnants of military activities, namely unexploded ordnance. Methodology of explosive ordnance clearance (EOC) is based on using of metal detectors.

The world wide experience witnesses some factors limiting or even eliminating their utilisation. Metal debris diminishes EOC reliability, when conducted in the outskirts of urban areas. Apart of this, there are cases when false alarms are observed without presence of any metal waste inside ground. This phenomenon was called “mineralisation of ground” initially. Term “mineralisation” was considered either as a content of mineralized groundwater or as a content of metallic minerals dispersed in rocks. However, the content of ferromagnetic minerals in rocks occurred under scientific interest. Research works have been conducted to clarify its nature and to recommend how to practise EOC procedures under those conditions.

Electromagnetic detection is based on the Faraday’s rule of mutual induction between searching coil and a target. From this point of view the expression “mineralized soil” should be rectified. Even impregnation of ferromagnetic materials inside absolutely non-conductive rocks can cause false signal of detector. This is the right reason of “mineralisation”. Where the bedrock consists of rocks containing magnetite, the success of electromagnetic searching occurs at risk.

Ondřej Kašpar

On Calculation of the Bearing Capacity of Self-opening Ground Anchors Using PLAXIS 2D Software Package

Abstract

The bearing capacity of a self-opening ground anchor is calculated using the empirical method and the plaxis software package. Stresses and strains can be determined in each element of the anchor using the approach based on the use of modern software packages enables to evaluate the stress-strain behavior of soil-structure system (geotechnical conditions taken into account), as well as the behavior of soil-anchor system as a whole and its individual elements. It is possible to estimate stresses in the area affected by the ground anchor, as well as the stability of the soil-anchor system as a whole.

Ivan E. Sas, Dmitry V. Morozov, Nikolay A. Morozov

Experimental Ballistic Loading of Steel Fiber Reinforced Concrete Slabs and Unreinforced Concrete Slabs by Plastic Explosives

Abstract

The article presents the results of experimental tests carried out on steel fiber reinforced concrete slabs and on unreinforced concrete slabs. The aim of the experimental tests was to determine its suitability for anti-spalling layer by using effects of plastic explosive PlHx 30 explosion. Slabs of steel fiber reinforced concrete and of plain concrete were made according to the same recipe. For this experiment, high-strength concrete with strength class C70/85 was used. In the mixture of steel fiber reinforced concrete, it was added 30 kg of fibers per 1 m³, type Dramix RC-65/50-BN. The interior surface of shelters walls must be protected against the concrete spalling, which are caused by detonations on the outside surface. The results of the tests proved that steel fiber reinforced concrete is not a suitable material for the anti-spalling layer.

Jiří Štoller, Petr Dvořák

Analysis of the Different Approaches to Protection of Critical Infrastructures in France and Slovakia

Abstract

The proposed paper is focused on the different approaches to protection of critical infrastructures. It compares the ways of protection of essential areas for human lives and society in France and Slovakia. It is focused on the Slovak and France legislation about the critical infrastructure, analyses the common features, differences and the methods of protection.

Figuli Lucia, Kavický Vladimír, Picot Sylvain

Experimental Studies of Blast Pressure Due to Vented Explosion of Methane-Air System

Abstract

A series of tests was conducted to investigate the blast resistances of the building to premixed methane-air interior burning and explosion. Explosion process of the gas methane medium (in the inner space) extremely depend on the object site configuration. An interior deflagration of premixed methane-air burning and explosion in a specific vented chamber can happens due the all hazards: natural, criminal, terrorist, and accidental. The full scale object was tested as control specimen. LVDTs and pressure transducers were used to record deflection histories, and pressure sensors measured airblast pressure histories. In the first stage of a study two experiments of methane-air system in differ proportion were carried out.

Alexander N. Kravtsov, Jacob Zdebski, Vaclav Pospichal, Petr Šelešovský

Theoretical Aspects of Critical Infrastructure Protection

Abstract

Theoretical, especially ontological approach to security examining in sector of critical, infrastructure is associated with a clear description of the object of interest, the expression of the principle of ontological security. Object of interest is the critical infrastructure sector, systematically organized into sub-elements and, as well as clarifying what the protection security is, what are its attributes and factors. The subject of research will be also interactions between security factors and their impact on the security situation. Clarification of ontological principles is to identify and to describe the causes that allow or give the security reason for existence, therefore something exists or may exist.

Ladislav Hofreiter, Zuzana Zvaková

Different Approaches to Setting the Blast Load of Structure

Abstract

The paper deals with the analysis of structure subjected to the blast load created by the explosion of ANFO explosives (ammonium nitrate and fuel oil). The paper presents the influence of blast wave idealisation on dynamical analysis of structure. Steel beam is loaded by different blast load model representing different ways of approximation of blast wave created after the explosion of explosive substances. The shape of blast pressure wave is idealised by three basic shapes – with linear decay time profile, exponential decay time profile, and exponential decay time profile considering negative phase. Dynamical analysis is done and the results from structures loaded by idealized profiles are compared with the experimental obtained results from the field test.

Figuli Lucia, Jangl Štefan, Picot Sylvain

Pressure Wave Propagation and Interaction with Structures

Abstract

The article deals with occurrence and propagation of pressure waves which can inflict substantial damage of structures and endanger the lives of soldiers and civilians. Nowadays, with the increasing incidence of terrorist acts, the use of Improvised Explosive Devices (IED) as a powerful non-conventional weapon is becoming more common. Important military objects or parts of military base entrance can be chosen as a target. For this reason, the protection of infrastructure against terrorist attacks is one of the main goals to be solved. To minimize negative effects of blast wave interaction with protective structures and shelters some knowledge of the mechanisms of explosion and shock wave propagation is necessary to provide the best available planning, design, and construction for needed disaster resistant facilities. The behaviour of the protective structure during an explosion depends entirely on the materials and design parameters used in the construction of the structure. The high performance fiber reinforced concrete (HPFRC) appears to be a promising material for protective structures. Testing of this material was carried out to assess its suitability for building civil defence shelters and pure military protective structures. The process of blast and shock wave propagation through the air and the concrete slab was numerically simulated and then suitable measuring system was designed and practical experiments were performed. The numerical simulations and the results of the experiment are compared and discussed in the article.

Zdeněk Hejmal

Laser-Ultrasound Imaging for the Investigation of Heterogeneous Media

Abstract

The development of a laser ultrasonic imaging technique for diagnostics of heterogeneous materials involves solving the inverse problem of ultrasound scattering. The paper describes the back-projection algorithm for the reconstruction of laser-ultrasonic images of inhomogeneous media. To demonstrate the capabilities of laser ultrasonic imaging, an experiment was carried out to reconstruct the image of an orifice 1 mm in diameter in a duralumin half-cylinder with a radius of 65 mm.

Alexander A. Karabutov, Elena B. Cherepetskaya, Anton S. Bychkov, Nikolay A. Morozov

Designing Military Constructions During Crisis Situation and New Elevation Data of the Czech Republic

Abstract

A really important measure of ensuring of the defense of the Republic is the Operational Preparation of National Territory. The Operational Preparation of National Territory also includes management of crisis situations especially during the attack critical infrastructure. The paper is focused on the possibilities for designing of temporary bridges and temporary roads in the destruction or disruption of the Critical Infrastructure. This paper shows the examples to use a new elevation data from airborne laser scanning country for the designing of military buildings. These data may serve as a base for creating digital terrain model of an area of interest. Subsequently, this digital terrain model is the base for designing of temporary bridges or temporary roads.

Jan Sobotka, Klára Cibulová

Engineer Construction of Provisional Bridges in the Army of Czech Republic

Abstract

This article analyzed the issue of provisional bridges engineer superstructures - mechanized bridges in the Army of the Czech Republic (ACR). Current devices are outdated and their parameters no longer correspond to the real needs of our military. Mechanized bridges are devices for rapid and effective security units move through impassable places (water obstacles, trenches, walls, etc.). They are designed not only for ACR units but also for transport means for intervention in emergency situations (floods, and other natural disasters) within the Integrated Rescue System (IRS). The article shows one of the options approach to modernization solutions to this type of provisional bridges, which is based on an analysis of current and real needs of the ACR.

Jindřich Holopírek, David Lysoněk

The Dynamic Modulus of Elasticity as an Important Parameter for Military Use of Constructions

Abstract

The article deals with the importance of the dynamic modulus of elasticity for military use of protective constructions. Not only the construction of the shelter has to save the crew inside, but also it should bear loading repeatedly. And the verification procedures of construction capability to withstand further load are being developed by military engineer specialist for the Czech armed force’s needs.

But for the verification of the real shelters construction is not possible to take samples. That’s why the non-destructive methods are used. From these methods is possible to obtain the dynamic modulus of elasticity and the static modulus has to be counted.

The paper contains the results of measurements of the dynamic modulus of elasticity with ultrasound to test of the 20 cubes made from the concrete and 18 cubes made from the steel fiber reinforced concrete. The dynamic modules of elasticity were converted to the static in accordance with Czech technical standard ČSN 73 2011 [2]. Non-destructive testing of concrete structures.

Eva Zezulová

Design and Assessment of Shape of Protective Structure by Usage of CFD Software Environment Ansys Fluent

Abstract

The purpose of the study was to design and assess the shape of the construction of the protective structure with regard to its building materials and technical possibilities for its production. Another indispensable limiting condition was the requirement for its easy transportability, assembly and modularity. The optimal shape solution was sought out by using CFD simulation carried out in the software environment of ANSYS Fluent. Appropriateness of different variants of the protective structure, differing form each other by parameterized shape, was assessed on the basis of a drag coefficient. After obtaining a representative number of measured values of the frag coefficient for each variant, results were processed using optimization methods built in the software environment Ansys Workbench, which has found its minimum value. On the basis of this value the most suitable candidate for the optimal variant of the shape of protective structure was chosen. This candidate was subsequently evaluated using the simulation for verification of forecasted value of its drag coefficient.

Jiří Štoller, Branislav Dubec

The Basic Properties of Materials Suitable for Protective Structures and Critical Infrastructure

Abstract

The deals with the basic properties of cement-based materials that are appropriate for protective structures and critical infrastructure. The basic properties of materials were tested on the material samples. The samples were tested before loading by the distant explosion, by the penetration and by the puncture. During the material testing were measured the compressive strength, the tensile strength and the dynamic modulus of elasticity. The article discusses only the compressive strength and the tensile strength.

Jiří Štoller, Eva Zezulová

Laser-Ultrasonic Monitoring of the Gritical Structure Objects Produced from CRFC

Abstract

Porosity is one of the most important composite structure failure, influenced on the properties of the construction and the residual service to fatigue. The non-destructive technologies able to detect the intimate structure transformation are well-come to the market. The comparative analysis of advantages and disadvantages of several technologies, such as X-ray tomography, conventional ultrasonic testing, thermal wave testing, remote laser-ultrasonic testing and contact laser-ultrasonic evaluation is presented. Contact laser-ultrasonic material evaluation seems to be the very technology for CFRF construction test. The advantages of contact laser-ultrasonic evaluation (CLUE) are described in detail. The possibility to evaluate the residual life-time of the objects of critical structure composite construction with CLUE is discussed.

Alexander A. Karabutov, Elena B. Cherepetskaya, Yulia G. Sokolovskaya, Elena A. Mironova, Dmitry V. Morozov, Pavel Svoboda

New Trends Used for Negotiation Untrafficable Terrain

Abstract

This article describes the results of measurement of new perspective material for negotiation low endurable terrain. It is based on the previous measurement with these materials, but enhanced by another vehicles and locations. There are described instruments for measuring the trafficability. The first one is the telescopic penetrometer used by the Czech Army and the second one is the cone penetrometer used by some NATO countries. The main aims of this article are the possibilities of overcoming low endurable terrain with perspective materials – mats. These mats were used during terrain measurements in extremely adverse conditions. It was tested weather the vehicles mired in terrain are able to pass with the mats. The procedures, the calculations and the results of the experiment are presented here.

Klára Cibulova, Jan Sobotka

The Protection of Critical Infrastructure Objects – Technical Principles

Abstract

The protection of critical infrastructure is not only the question of their resilience but in a technical point of view, it is a question of protection of function of particular objects of critical infrastructure. This protection of objects depends on possible threats which are heavily to determine, one of possible way is to use commonly agreed procedures like e.g. STANAG 2280. Possibilities in assessment of structures facing to attack are described and examples of simulation are given.

Pavel Maňas

Using of Intelligent Transport Systems to Elimination of the Negative Effect on the Transport Security

Abstract

Paper is focused on the important aspects of the deployment and the use of intelligent transport systems in road transport. Intelligent transport system are one of the tool how to increase the security of one of the sectors of critical infrastructure – transport. The paper defines the concept of traffic safety and assesses the current condition of road safety in the European Union. The paper concludes with the design of varying Electronic Bulletin Board, as a tool of intelligent transport systems. It has bring the elimination of negative impacts of transport systems in road transport.

Michal Ballay, Lucia Figuli, Zuzana Zvaková

Backmatter