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1

Stabilization of Expansive Soil Mixture Using Human Hair Fibre (Biopolymer)

Idoui Imane, Bekkouche Souhila Rehab, Benzaid Riad, Berdi Inas

Civil and Environmental Engineering Reports

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2024

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Vol. 34, no. 2

63--75

EN

Expansive soils sensitivity to volumetric change is one of the well-known challenges in the field of geotechnical engineering. Various attempts have been made by researchers to solve this problem. Current research presents the effect of human hair fibers on the behavior of expensive soils. A reconstituted soil of 80% kaolin as raw material and 20% bentonite with different percentages of human hair (0%, 0.5%, 1%, 1.5% and 2%) was used. The microstructure of the formulations was characterized by studying the interactions between soil and human hair using scanning electron microscopy (SEM). The microstructure of the formulations was characterized by studying the interactions between soil and human hair using scanning electron microscopy (SEM). Atterberg limits, compaction characteristics, swelling parameters, compressibility and shear strength were also examined. The results of this study indicate that the inclusion of human hair fibers significantly improves the properties of the expansive soil mixture. These results open up new prospects for the stabilization of expansive soils.

2

Stabilizacja finansów publicznych wyzwaniem polityki gospodarczej Polski

Wierucka Julia

Studia Bezpieczeństwa Narodowego

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2023

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R. 13, Nr 28

97--110

PL

Celem przedmiotowej pracy jest analiza i ocena jednego z głównych wyzwań ekonomicznych Polski na najbliższe lata, mianowicie ustabilizowania systemu finansów publicznych oraz wyhamowania wzrostu długu publicznego. Główny problem badawczy pracy określono w formie pytania: Jak przedstawia się sytuacja stabilizacji sektora finansów publicznych, w dobie dzisiejszych wyzwań i zagrożeń istniejących w polityce gospodarczej, jak i na arenie międzynarodowej? Jako problemy szczegółowe określono: obecną sytuację finansów publicznych w Polsce, będącą podstawą tej analizy, zakres definicyjny podmiotu sprawy, jak i określenie czynników wpływu na mający miejsce rozwój wydarzeń. W nawiązaniu do przedstawionych problemów badawczych wysnuta została hipoteza, iż prowadzone działania w zakresie stabilizacji finansów RP są niewystarczające do aktualnych wydarzeń. Hipoteza została oparta o wyniki statystyczne przedstawione w artykule. W pracy zastosowano następujące metody badawcze: definiowanie, które pozwoliło na określenie jednoznaczności terminów, analizę i syntezę, które pozwoliły na odpowiednią interpretacje zastanych danych, indukcję i dedukcję, które pozwoliły na znalezienie odpowiedzi na rozważne w pracy pytanie badawcze. W pracy posłużono się także metodą analizy porównawczej w zakresie definicji dotyczących omawianego zakresu. Zastosowano również analizę źródeł, monografii, artykułów naukowych traktujących o badanej tematyce.

EN

The aim of this paper is to analyze and assess one of the main economic challenges for Poland in the coming years, namely stabilizing the public finance system and slowing down the growth of public debt. The main research problem of the work was defined in the form of a question: what is the situation of stabilization of the public finance sector in the era of today's challenges and threats in economic policy and in the international arena? The following were defined as specific problems: the current situation of public finances in Poland, which is the basis for this analysis, the definition scope of the subject of the case, as well as determining the factors affecting the development of events. With reference to the presented research problems, a hypothesis was put forward that the activities carried out in the field of stabilizing the finances of the Republic of Poland are insufficient to current events. The hypothesis was based on the statistical results presented in the article. The following research methods were used in the work: defining, which allowed to determine the unambiguity of terms, analysis and synthesis, which allowed for the appropriate interpretation of the existing data, induction and deduction, which allowed finding the answer to the research question considered in the work. The work also uses the method of comparative analysis in terms of definitions regarding the discussed scope. An analysis of sources, monographs, and scientific articles dealing with the researched subject was also used.

3

Odtajnione, polskie wynalazki z technologii indywidualnych, kruszących materiałów wybuchowych

Miszczak Maciej

Problemy Techniki Uzbrojenia

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2023

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R. 52, z. 163

75--92

PL

W artykule przedstawiono rezultaty poszukiwań i analiz treści odtajnionych opisów patentowych polskich wynalazków z zakresu technologii kruszących materiałów wybuchowych w postaci indywiduów chemicznych, takich jak nitroskrobia, trotyl, dinitrotoluen, tetryl, pentryt, heksogen i oktogen. W wyniku poszukiwań znaleziono dziewięć opisów patentowych wynalazków [1-9], przy czym trzy [2-4] dotyczyły stabilizacji nitroskrobii, jeden [1] stabilizacji pentrytu i heksogenu, jeden [6] oczyszczania trotylu od kwasów ponitracyjnych, jeden [7] - suszenia trotylu i dinitrotoluenu oraz trzy [5,8,9] – sposobów otrzymywania odpowiednio tetrylu, trotylu i oktogenu. Wynalazki te zgłoszono jako tajne do Urzędu Patentowego w latach 1948-1996, zaś o zdjęciu z nich klauzuli tajności ogłoszono w Wiadomościach Urzędu Patentowego RP w latach 2007-2016.

EN

Results of searches and analyses of the Polish disclosed secret patents on technology of high-explosives in the form of such chemical individuals as nitrostarch, trotyl, dinitrotoluene, tetryl, penthrite, hexogen and octogen, are presented in the paper. As a result of the above searches, nine patent descriptions [1-9] of inventions were found, and among them three [2-4] dealt with nitrostarch stabilization, one [1] with stabilization of penthrite and hexogen, one [6] with trotyl cleaning from post-nitrating acids, one [7] with trotyl and dinitrotoluene drying, and three [5,8,9] with obtainment of tetryl, trotyl and octogen, respectively. The inventions were ap-plied as secret ones to the Patent Office in 1948-1996, and the secrecy clause was lifted from them by the announcements of the News of the Patent Office of the Republic of Poland in 2007-2016.

4

Stabilization of multivariable linear time-invariant systems by proportional-plus-derivative state feedback

Kiritsis Konstadinos H.

Control and Cybernetics

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2023

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Vol. 52, No. 1

53--77

EN

This paper is devoted to the study of the problem of stabilization by proportional-plus-derivative state feedback for multivariable linear time-invariant systems. In particular, explicit necessary and sufficient conditions are established for the stability of a closed-loop system obtained by proportional-plus-derivative state feedback from the given multivariable linear time-invariant system. A procedure is given for the computation of stabilizing proportional- plus-derivative state feedback. Our approach is based on properties of real and polynomial matrices.

5

Review, design, stabilization and synchronization of fractional-order energy resources demand-supply hyperchaotic systems using fractional-order PD-based feedback control scheme

Soukkou Ammar, Soukkou Yassine, Haddad Sofiane, Benghanem Mohamed, Rabhi Abdelhamid

Archives of Control Sciences

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2023

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Vol. 33, No. 3

539--563

EN

This paper introduces a fractional-order PD approach (F-oPD) designed to control a large class of dynamical systems known as fractional-order chaotic systems (F-oCSs). The design process involves formulating an optimization problem to determine the parameters of the developed controller while satisfying the desired performance criteria. The stability of the control loop is initially assessed using the Lyapunov’s direct method and the latest stability assumptions for fractional-order systems. Additionally, an optimization algorithm inspired by the flight skills and foraging behavior of hummingbirds, known as the Artificial Hummingbird Algorithm (AHA), is employed as a tool for optimization. To evaluate the effectiveness of the proposed design approach, the fractional-order energy resources demand-supply (Fo-ERDS) hyperchaotic system is utilized as an illustrative example.

6

Zastosowanie quasi-prędkości do stabilizacji Pendubota

Parulski Paweł, Pazderski Dariusz, Bartkowiak Patryk

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2022

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z. 197, t. 1

59-70

PL

Celem niniejszego artykułu jest zbadanie metody sterowania wykorzystującej quasi-prędkości znormalizowane do stabilizacji podwójnego wahadła o strukturze pendubota. W pracy przedstawiono model robota i jego przekształconą postać z użyciem quasi-prędkości. Omówiono strukturę układu sterowania uwzględniającą stabilizator w punkcie zadanym oraz sterownik zapewniający rozkołysanie wahadła. Przedstawione wyniki badań symulacyjnych i eksperymentalnych wskazują na pozytywne efekty użycia quasi-prędkości do syntezy algorytmów sterowania rozważaną klasą układów mechanicznych.

EN

The aim of this paper is to investigate a control method using normalized quasi-velocities to stabilise a double pendulum commonly known as the Pendubot. The paper presents the robot model and its transformed from using quasi-velocities. The structure of the control system is discussed, taking into account the sabiliser at the set point and the controller ensuring theswing0up task. The presented results of simulation and experimental studies indicate positive effects of using quasi-velocities for the synthesis of control algorithms for the considered class of mechanical systems.

7

Stabilization of the wave equation with a nonlinear delay term in the boundary conditions

Ghecham Wassila, Rebiai Salah-Eddine, Sidiali Fatima Zohra

Journal of Applied Analysis

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2022

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Vol. 28, nr 1

35--55

EN

A wave equation in a bounded and smooth domain of ℝn with a delay term in the nonlinear boundary feedback is considered. Under suitable assumptions, global existence and uniform decay rates for the solutions are established. The proof of existence of solutions relies on a construction of suitable approximating problems for which the existence of the unique solution will be established using nonlinear semigroup theory and then passage to the limit gives the existence of solutions to the original problem. The uniform decay rates for the solutions are obtained by proving certain integral inequalities for the energy function and by establishing a comparison theorem which relates the asymptotic behavior of the energy and of the solutions to an appropriate dissipative ordinary differential equation.

8

Stabilization of polynomial systems in ℝ3 via homogeneous feedback

Jerbi Hamadi, Kharrat Thouraya, Mabrouk Fehmi

Journal of Applied Analysis

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2022

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Vol. 28, nr 2

189--197

EN

In this paper, we study the stabilization problem of a class of polynomial systems of odd degree in dimension three. The constructed stabilizing feedback is homogeneous and guarantee the homogeneity of the closed loop system.mynotered In the end of the paper, we show the efficiency of such a study in the local stabilization of nonlinear systems affine in control.

9

Stability analysis and design of state estimated controller for delay fuzzy systems with parameter

Hadj Taieb Nizar, Hammami Mohamed Ali, Delmotte François

Archives of Control Sciences

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2022

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Vol. 32, No. 4

709--731

EN

This paper deals with the problem of stabilization by an estimated state feedback for a family of nonlinear time-delay Takagi-Sugeno fuzzy parameterized systems. The delay is supposed to be constant where the parameter-dependent controls laws are used to compensate the nonlinearities which are formulated in terms of linear matrix inequalities (LMIs). Based on the Lyapunov-Krasovskii functionals, global exponential stability of the closed-loop systems is achieved. The controller and observer gains are able to be separately designed even in the presence of modeling uncertainty and state delay. Finally, a numerical example is given to show the applicability of the main result.

10

Study on some of the strength properties of soft clay stabilized with plastic waste strips

Kabeta Worku Firomsa

Archives of Civil Engineering

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2022

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Vol. 68, nr 3

385--395

EN

It is well known that if plastic wastes are not well managed, it has a negative impact on the environment as well as on human health. In this study, recycling plastic waste in form of strips for stabilizing weak subgrade soil is proposed. For this purpose, a weak clay soil sample was mixed with 0.2%, 0.3%, and 0.4% of plastic strips by weight of soil, and the experimental results were compared to the control soil sample with 0% plastic. Laboratory tests on the Standard compaction test, Unconfined compression test (UCS), and California bearing ratio (CBR) were conducted according to the American Society for Testing and Materials (ASTM). The results of the study reveal that there are significant improvements in the strength of weak soil stabilized with plastic waste strips. Accordingly, the Standard Proctor test shows that there is a small increment in the maximum dry density of the soil when it is mixed with plastic strips. The result from the CBR test shows that there is a significant increment of CBR value with the plastic strip content. The unconfined compressive strength test also shows that increasing the percentage of plastic strips from 0 to 0.4% resulted in increased strength of soil by 138% with 2 cm length plastic strips. Therefore, this study recommends the application of plastic strips for improvement of the strength of soft clay for subgrade construction in civil engineering practice as an alternative weak soil stabilization method.

11

Hydraulic Stability of Fly Ash-Bentonite Mixtures in Landfill Containment System

Budihardjo Mochamad Arief, Syafrudin Syafrudin, Priyambada Ika Bagus, Ramadan Bimastyaji Surya

Journal of Ecological Engineering

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2021

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Vol. 22, nr 7

132--141

EN

This study aimed to examine the performance of fly ash mixed materials with bentonite binder (FAB) as a recent low-cost containment system to withstand leachate infiltration. The mixture of fly ash with clay (bentonite) can increase the strength of stability and strengthen cohesion bonds between molecules. Direct shear, falling head, Atterberg limit and specific gravity test have been conducted as a preliminary study to determine the precise mixture composition of fly ash-bentonite (FAB) landfill liners. Some bentonite composition: 0% (FAB0), 15% (FAB15), 20% (FAB20), 25% (FAB25) and 25% – cured with NH4Cl (FAB25s) for 24 hours, which mixed with fly ash, showed the value of shear stability at normal stress reaching 9.5 kNm-2, 15.48 kNm-2, 45.06 kNm-2, 46.26 kNm-2 and 13.67 kNm-2, respectively. It showed that the greater the content of bentonite in the mixture, the higher the shear stress produced. Curing with saline solution can reduce the shear stress of the FAB mixture. The safety test results using Geoslope/W® show that the addition of bentonite will increase bonding between particles, bearing capacity, and shear strength of the material. The largest safety factor of 1.674 obtained from FAB20 material meets the safety standard for short-term slope stability. The use of fly ash material with bentonite is expected to be an alternative landfill liner material.

12

Influence of DLC coatings modification on load transfer by the guided growth stabilization system modelling the spine during the age of growth

Żak Małgorzata, Szotek Sylwia, Filipiak Jarosław, Rutkowska-Gorczyca Małgorzata, Brunicka Ewalina, Pezowicz Celina

Engineering of Biomaterials

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2021

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Vol. 24, no. 163

113

13

Zagadnienia stabilizacji elektromagnesów nadprzewodnikowych

Sosnowski Jacek

Elektronika : konstrukcje, technologie, zastosowania

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2021

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Vol. 62, nr 1

11--14

PL

W artykule przedyskutowano zagadnienia stabilizacji elektromagnesów nadprzewodnikowych. Zagadnienie to ma istotne znaczenie przy wykorzystaniu elektromagnesów np. w projekcie PolFEL. Przytoczono podstawowe definicje określające zagadnienia stabilizacji i określono występujące tu podstawowe parametry, jak minimalna długość propagacji, parametr Stekley’a, teoria równych powierzchni. Rozpatrzono warunki stabilizacji określające prawidłową pracę elektromagnesów, podano ilustrację doświadczalną utraty stabilności poprzez generację skoków strumienia oraz zbadano efektywność chłodzenia cieczami kriogenicznymi w funkcji różnicy temperatur.

EN

The article discusses the stabilization of the superconducting electromagnets. This issue is important from the point of view of the applications of superconducting electromagnets, e.g. in the PolFEL project. Basic definitions determining the stabilization issues were given and the essential parameters, such as the minimum propagation length, the Stekley parameter, the theory of equal surfaces were discussed. The stabilization conditions determining the correct operation of the electromagnets were considered, and an experimental illustration of the stability decline leading to the flux jumps was given. The efficiency of cooling with cryogenic liquids as a function of temperature difference was analysed.

14

Contribution to the Valorization of Granulated Blast Furnace Slag in Soil Stabilization

Djouimaa Sarah, Missaouri Sabrina, Handel Naoual, Sid Madani

Civil and Environmental Engineering Reports

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2021

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Vol. 31, no. 3

134--151

EN

The treatment of expansive soil is generally the most effective process for the stabilization of swelling clay. In this work, we will investigate the influence of the treatment of an expansive soil using granulated blast furnace slag (GGBS) alone and granulated blast furnace slag activated by cement (GGBS/C) by mechanical, physical and chemical tests. The results obtained show an increased pH, an improved plasticity as well as a significant reduction in swelling potential and swelling pressure following a percentage increase in additives. In addition, a change in the adsorption of methylene blue molecules (VBs) and in the microstructure of the expansive soil is observed after treatment. Utilization of both GGBS alone and GGBS activated by cement has a significant effect on the behavior of the swelling clay but the GGBS activated by cement exhibits superior results. The use of GGBS in the stabilization of soil will have both economic and environmental benefits.

15

Effect of marble dust and glass fiber on expansive soil

Shukla Rajesh P., Algotari Divyanshu, Rathod Mahendrasinh

Inżynieria Mineralna

|

2020

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no. 2, vol. 2

111--118

EN

India shares a significant production of glass fiber and marble wastes in the world, which poses a big disposal problem. This study assesses the suitablility of glass fiber and marble dust to enhance the behaviour of expansive soil. The Atterberg’s limits and plasticity index improves by mixing marble dust into the soil. Whereas, the effect of glass fiber on the Atterberg’s limit is not found to be encouraging. The shear strength increases with the addition of marble dust as well as glass fibres. The effect of glass fiber on strains corresponding to peak stress is significantly higher than the marble dust. The strength of fiber-reinforced soil initially increases with the addition of marble dust, to the certain extent, beyond with it decreases. The effect of marble dust on variation in peak stress and corresponding strains is fibre-reinforced soil is found to be almost opposite. The optimum quantity of marble dust and glass fiber is found to be 10%-15% and 3%, respectively.

PL

Gleby ekspansywne to gleby, które mają zdolność kurczenia się i / lub pęcznienia, a tym samym zmiany objętości, w zależności od zmian wilgotności. Utylizacja odpadów przemysłowych to duży problem w Indiach. Obecnie wiele produktów odpadowych stało się popularnymi materiałami konstrukcyjnymi. W niniejszej pracy oceniano przydatność zbrojenia włóknem szklanym do poprawy wytrzymałości gruntu ekspansywnego. Ponadto określa się również wpływ pyłu marmurowego na grunt wzmocniony włóknami. Limity Atterberga i wskaźnik plastyczności poprawiają się poprzez mieszanie pyłu marmurowego z glebą. Natomiast wpływ włókna szklanego na granicę Atterberga nie jest zachęcający. Wytrzymałość na ścinanie wzrasta wraz z dodatkiem pyłu marmurowego oraz włókien szklanych. Jednak wpływ włókna szklanego jest relatywnie bardziej zauważalny w porównaniu z pyłem marmurowym. Stwierdzono, że optymalna ilość pyłu marmurowego i włókna szklanego wynosi odpowiednio 15% i 3%. W przypadku włókna szklanego wytrzymałość na ściskanie i odpowiednie odkształcenie wzrastają odpowiednio o 55–58% i 700%. W gruncie zbrojonym włóknem wytrzymałość początkowo wzrasta wraz z dodatkiem pyłu marmurowego, do pewnego stopnia, po przekroczeniu której maleje. Stwierdzono, że wpływ pyłu marmurowego na zmienność szczytowych naprężeń i odpowiadających im odkształceń gleby wzmocnionej włóknami jest prawie przeciwny.

16

Wellposedness and long time behavior for a general class of Moore-Gibson-Thompson equations

Nicaise Serge, Bounadja Hizia

Control and Cybernetics

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2020

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Vol. 49, No. 3

245--276

EN

We consider the well-posedness and the long time behavior of third order in time linear evolution equations, general and abstract version of the Moore-Gibson-Thompson system. We find sufficient but strong conditions that guarantee the exponential decay of the system and present some illustrative examples. Then, by comparing the behavior of the resolvent of the Moore-Gibson-Thompson system with the one of the resolvent of the wave equation with a frictional interior damping, we furnish weaker conditions that guarantee exponential, polynomial or even logarithmic decay of the solution of the Moore-Gibson-Thompson system in a bounded domain of Rn, n ≥ 1.

17

Stability and stabilization of positive linear dynamical systems: new equivalent conditions and computations

Yang H., Hu Y.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2020

|

Vol. 68, nr 2

307--315

EN

New equivalent conditions of the asymptotical stability and stabilization of positive linear dynamical systems are investigated in this paper. The asymptotical stability of the positive linear systems means that there is a solution for linear inequalities systems. New necessary and sufficient conditions for the existence of solutions of the linear inequalities systems as well as the asymptotical stability of the linear dynamical systems are obtained. New conditions for the stabilization of the resultant closed-loop systems to be asymptotically stable and positive are also presented. Both the stability and the stabilization conditions can be easily checked by the so-called I-rank of a matrix and by solving linear programming (LP). The proposed LP has compact form and is ready to be implemented, which can be considered as an improvement of existing LP methods. Numerical examples are provided in the end to show the effectiveness of the proposed method.

18

Electro pneumatic control system for inverted pendulum

Popławski Krzysztof, Ambroziak Leszek, Kondratiuk Mirosław

Acta Mechanica et Automatica

|

2020

|

Vol. 14, no. 2

91--97

EN

The paper concerns the inverted pendulum control system with using pneumatic cylinder. A mathematical model of the pendu-lum used to derive the LQG controller was presented. Prepared laboratory stand was presented and described in detail. The main purpose of the work was experimental researches. A number of control process tests were conducted with variable model parameters such as addi-tional mass, injected disturbances and so on. The results were shown on the time plots of the control object states.

19

Zagrożenie zabytków dziedzictwa kulturowego ruchami masowymi na obszarze Karpat

Laskowicz Izabela, Mrozek Teresa

Przegląd Geologiczny

|

2019

|

Vol. 67, nr 5

369--376

EN

Owing to intensification of extreme rainfall events widespread land-sliding has been observed in the Carpathians since the 1990s. This area is also known for many cultural heritage objects e.g. manors, castles, sacred buildings, technical structures, whole villages and urban layouts. Here, the natural propensity to slope failure was often overlooked, so was a potential landslide hazard. This work presents the list of cultural heritage objects that have been affected by a landslide hazard. and that total to 445 historic sites. In the group of the most endangered, there are 12 heritage buildings located on active landslides. Using selected examples of masonry and wooden structures, the sacred historical heritage assets and manors are discussed in a context of landsliding threats and related preventive measures. This paper also shows that the structural stabilization implemented for a historical site was successful and withstood an impact of extreme precipitation during the spring/summer 2010. However, the assessment of landslide hazard requires, first of all, a full inventory of the threatened monuments and historical sites.

20

Rezultaty techniczne stabilizacji osuwiska na historycznym wzgórzu Rotunda

Trojnar Krzysztof, Siry Józef, Smajdor Wojciech

Magazyn Autostrady

|

2019

|

Nr 5

44--48

PL

W artykule przedstawiono doświadczenia ze stabilizacji osuwiska na historycznym wzgórzu Rotunda w Krzeszowie. Zabezpieczenie polegało na wykonaniu metodami geoinżynieryjnymi bloków gruntowo-cementowych o określonych kształcie i rozmiarach, pełniących funkcję sztywnych przypór w zboczu osuwiskowym. Przeprowadzono szczegółową analizę obliczeniową stateczności zagrożonego terenu i zaproponowano optymalny sposób zabezpieczenia z wykorzystaniem technologii wgłębnego mieszania gruntu (DSM). Układ i konstrukcję przypór z paneli DSM przyjęto według autorskiego projektu stabilizacji osuwiska. Po zakończeniu prac stabilizacyjnych historyczne wzgórze Rotunda zachowało niezmienione formę i kształt.

EN

The article describes experiences from the stabilization of landslide on the historic Rotunda hill in Krzeszów. The method consisted in the fabrication of ground and cement blocks, used as the rigid supports of the slope. The calculation analysis of stability was carried out and the optimum method of protection by the Deep Soil Mixing (DSM) technology was applied. The arrangement and construction of DSM panels was adopted according to the authors’ project of landslide stabilization. After the stabilization works had been completed, the historical Rotunda hill retained its form and shape.