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1

Investigating effectiveness of tuned mass damper (TMD) on control vibration of wind turbine-soil interaction

Vatanshenas Ali

Structure and Environment

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2025

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Vol. 17, no. 1

18--27

EN

Soil-structure interaction (SSI) effects were investigated on structural responses of wind turbine. Force versus deformation (i.e., p-y curves) was simulated by multilinear elastic springs. The whole system, including the structure, control vibration system and soil nonlinear effects are simulated within a single three-dimensional finite element model. Modeling accuracy was verified using available results related to a 65 kW wind turbine discussed in the literature. Pushover analysis results indicated a fixed-base assumption ends up with overestimation of stiffness compared to the case where SSI effects are considered. Moreover, it is observed that the performance of tuned mass damper (TMD) is highly dependent on its tuned frequency domain, and its efficiency decreases significantly after SSI effects are considered. Lateral deformations of a wind turbine are much higher compared to the fixed-base condition. Therefore, SSI effects play a crucial part in designing wind turbines and should not be neglected in practice.

PL

Zbadano wpływ interakcji konstrukcji z podłożem gruntowym (SSI) na zachowanie konstrukcji turbiny wiatrowej. Zależność siły od odkształcenia (tj. krzywe p-y) zasymulowano za pomocą wieloliniowych sprężyn elastycznych. Cały system, w tym konstrukcja, system kontroli wibracji i nieliniowe efekty podłoża, jest symulowany w ramach jednego trójwymiarowego modelu elementów skończonych. Dokładność modelowania została zweryfikowana przy użyciu dostępnych wyników dla turbiny wiatrowej o mocy 65 kW, omówionych w literaturze. Wyniki analizy statycznej (pushover) wykazały, że przy założeniu o nieruchomej podstawie dochodzi do przeszacowania sztywności w porównaniu z przypadkiem, w którym uwzględniono efekty SSI. Ponadto zaobserwowano, że wydajność tłumika TMD jest silnie zależna od jego dostrojonej domeny częstotliwości, a jego efektywność znacznie spada po uwzględnieniu efektów SSI. Odkształcenia poziome turbiny wiatrowej są znacznie większe w porównaniu z warunkami nieruchomej podstawy. Dlatego efekty SSI odgrywają kluczową rolę w projektowaniu turbin wiatrowych i nie powinny być pomijane w praktyce.

2

Behavioural analysis of a residential building subjected to influences of discontinuous ground deformations: case study in the Upper Silesia, Poland

Szojda Leszek, Kotala Bernard

Archives of Mining Sciences

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2025

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Vol. 70, no. 2

163--181

EN

The end of the long-term exploitation of minerals makes it possible to stop maintaining underground infrastructure and pumping out water. This raises the groundwater table and may cause changes in the mechanical parameters of the subsurface soil layers. The occurrence of these phenomena in urban areas has raised concerns about the safety of residential buildings subject to such influences. The analysed two-storey building, without a basement, had a square plan and a typical brick wall structure with RC structural elements: foundation strips, inter-storey ceilings, ring beams on load-bearing walls and stairs. The numerical model also included the groundmass to consider the soil-structure interaction effect. During the calculations, all loads occurring during the standard operation of the building and two locations of the sinkhole under the building’s foundations were considered. The results of the analyses are presented in the form of colour maps showing the displacement of the building, the change in stresses in the soil under the foundations, the change in the principal stresses in the building structure and the possibility of cracks appearing. The analyses show that the building will not be destroyed, but there will be damage to the load-bearing walls.

3

Analysis of soil-structure interaction using 2D/3D FEM calculations in geotechnical design

Kacprzak Grzegorz, Bodus Seweryn, Świerc Błażej, Zabora Zofia, Wojno Wiktoria, Grzywocz Wojciech, Hanasz Urszula

Archives of Civil Engineering

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2025

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Vol. 71, nr 4

527--541

EN

Geotechnical design is a complex, interdisciplinary field involving soil science, mechanics, and rheology. This article presents a comprehensive solution for geotechnical design using digital data from various programs, focusing on Ultimate Limit State (ULS) and Serviceability Limit State (SLS) analysis for a storage hall foundation in challenging geotechnical conditions in eastern Germany. The study utilizes the groundwater conditions and layer layout from the Leapfrog software to create a spatial computational model of the subsoil using Plaxis 3D FEM based on nearly 400 virtual boreholes. Data on hall geometry and load combinations were stored in digital IFC format and tabular data in Excel files respectively. The analysis involved both analytical and FEM 3D/2D methods. In the analytical method, all digital information was collected into one Excel file database for further calculations. Once the consistent digital project database was collected, the same data was implemented into the Plaxis 3D program for FEM numerical calculations. The hall’s foundation solution used footings supported by drilled piles. Soil layer parameters were calibrated based on static pile tests during design calculations. Due to part of the hall being located in a high embankment area (about 5 meters high), consolidation analysis of cohesive soils in the area was considered. The impact of consolidation was factored into negative skin friction in the ULS pile design process. Pile geometry was tailored to existing soil conditions and weak bearing soil thickness. The final foundation geometry and pile lengths were designed to meet SLS conditions set by the structural designer and to address uneven building settlement.

PL

Projektowanie geotechniczne jest dziedziną trudną i interdyscyplinarną wykorzystującą gruntoznawstwo, mechanikę gruntów, mechanikę budowli, zjawiska reologiczne etc. Artykuł ma na celu zaprezentowanie kompleksowego rozwiązania projektowania geotechnicznego w przypadku posiadania cyfrowej informacji wielu danych projektowych pochodzących z różnych programów obliczeniowych. Praca dotyczy tematyki projektowania geotechnicznego z analizą stanów granicznych nośności i użytkowalności na przykładzie koncepcji projektowej posadowienia hali magazynowej w trudnych warunkach geotechnicznych wschodnich Niemiec. Wykorzystując informacje dotyczące warunków gruntowo-wodnych i układu warstw z modelu programu Leapfrog zbudowano przestrzenny model obliczeniowy podłoża w metodzie analitycznej i programie numerycznym Plaxis 3D MES bazując na blisko 400-stu wirtualnych odwiertach. Informacje na temat geometrii hali o długości 330 m i szerokości 150 m zapisana została w pliku ifc. Oddziaływania w postaci kilkunastu projektowanych kombinacji obciążeń na stopy fundamentowe z ich lokalizacją w globalnym układzie współrzędnych zostały zapisane w postaci danych tabelarycznych plików Excel. Analiza wykonywana była dwutorowo tj. z wykorzystaniem analitycznych, obliczeniowych metod empirycznych oraz obliczeniowej analizy MES 3D/2D. W metodzie analitycznej wszystkie cyfrowe informacje zostały zebrane w jedną bazę danych programu Excel, gdzie przeprowadzono dalsze obliczenia. Po utworzeniu spójnej cyfrowej bazy danych projektowych te same informacje zostały zaimplementowane do programu Plaxis 3D w celu wykonania obliczeń numerycznych MES. Rozwiązanie posadowienia hali zaprojektowano w technologii stóp fundamentowych posadowionych na palach wierconych. Na etapie obliczeń projektowych przeprowadzana została kalibracja parametrów warstw gruntowych w oparciu o badania statyczne pali. Z powodu posadowienia części geometrii hali na obszarze wysokiego nasypu (ok 5 m wysokości) w obliczeniach wykonano analizę konsolidacji gruntów spoistych występujących na projektowanym obszarze. Wpływ konsolidacji został uwzględniony w postaci tarcia negatywnego przy projektowaniu SGN pali. Geometria pali została dopasowana do panujących warunków gruntowych, miąższości warstw słabonośnych. Ostateczna geometria fundamentów hali w tym długości pali zostały zaprojektowane, aby spełnić warunek SGU narzucony przez projektanta konstrukcji oraz wyrównać nierównomierne osiadania budynku.

4

The influence of soil structure interaction on the placement of active control systems in structures

Reteri Khadidja, Megnounif Abdellatif

Acta Mechanica et Automatica

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2025

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Vol. 19, no. 1

44--53

EN

This article begins by outlining the developed program and subsequently applies it to typical structures to emphasize the importance of active control and SSI. The study involves a comparison of dynamic response and control force results to determine the optimal controller position for a column-beam type structure, with and without considering SSI. The central question addressed is whether the influence of soil-structure interaction can be disregarded in selecting the optimal controller position.To address this, a digital simulation is conducted on a simple three-story structure within this document.

5

Analysis of the behavior of structures under the effect of progressive rupture of a cavity

Boualleg Bilel, Bouacha Nadjet

Studia Geotechnica et Mechanica

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2024

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Vol. 46, nr 3

244--258

EN

The ground movements related to the presence of old underground cavities are often damaging to structures and infrastructures. Considering these ground movements in calculations will prevent considerable human loss and material damage. Many areas, both in Algeria and in abroad, are prone to instability caused by ground rupture and the phenomenon of sinkhole progression. The objectives of this work are first to numerically simulate the process of cavity collapse and second to analyze the impact of cavity properties on structure stability. A finite element model was established to analyze the influence of several cavity parameters (dimensions, volume, and spacing). Validation of the model relied on comparing numerical results with experimental data from scientific research, as well as those from analytical approaches. Adequate correlation was achieved. The study allowed deriving mathematical equations relating to several parameters, including cavity dimensions and position in the soil, soil characteristics, and footing width. These results will be considered to reduce the risk of surface structure instability.

6

Numerical analysis of the flexible manhole-soil interaction in mining areas based on the laboratory test results

Janoszek Tomasz, Kalisz Piotr, Zięba Magdalena

Mining Science

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2024

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Vol. 31

183--198

EN

Horizontal soil strains, caused by underground mining, change the distribution and values of loads acting on a manhole. The result of a significantly unbalanced distribution of horizontal loads on a flexible manhole is the cross-sectional deflection, which causes passive soil pressure. These loads may damage manholes, leading to failures of the sewer system. The article employs numerical modelling to analyse the interaction between a flexible manhole and horizontally strained soil for the conditions of the performed laboratory tests. The numerical simulations were conducted with FLAC3D v.5.0. software, based on the finite difference method. The numerical analyses showed that in mining areas the cross-sectional deflection of flexible manhole risers depends on the horizontal soil strains, the ring stiffness of the risers and the foundation depths of manholes.

7

Convolutional neural networks in the SSI analysis for mine-induced vibrations

Zając Maciej, Kuźniar Krystyna

Computer Assisted Methods in Engineering and Science

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2024

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Vol. 31, no. 1

3--28

EN

Deep neural networks (DNNs) have recently become one of the most often used softcomputational tools for numerical analysis. The huge success of DNNs in the field of imageprocessing is associated with the use of convolutional neural networks (CNNs). CNNs,thanks to their characteristic structure, allow for the effective extraction of multi-layerfeatures. In this paper, the application of CNNs to one of the important soil-structureinteraction (SSI) problems, i.e., the analysis of vibrations transmission from the free-field next to a building to the building foundation, is presented in the case of mine-induced vibrations. To achieve this, the dataset from in-situ experimental measurements,containing 1D ground acceleration records, was converted into 2D spectrogram imagesusing either Fourier transform or continuous wavelet transform. Next, these images wereused as input for a pre-trained CNN. The output is a ratio of maximal vibration valuesrecorded simultaneously on the building foundation and on the ground. Therefore, the lastlayer of the CNN had to be changed from a classification to a regression one. The obtainedresults indicate the suitability of CNN for the analyzed problem.

8

The Effect of Soil-Structure Interaction (SSI) on Structural Stability and Sustainability of RC Structures

Krishnan Ragi, Sivakumar Vidhya Lakshmi

Civil and Environmental Engineering Reports

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2024

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Vol. 34, no. 1

116--136

EN

The issue of SSI involves how the ground or soil reacts to a building built on top of it. Both the character of the structure and the nature of the soil have an impact on the stresses that exist between them, which in turn affects how the structure and soil beneath it move. The issue is crucial, particularly in earthquake regions. The interaction between soil and structure is an extremely intriguing factor in increasing or reducing structural damage or movement. Structures sitting on deformable soil as opposed to strong soil will experience an increase in static settlement and a decrease in seismic harm. The engineer must take into account that the soil liquefaction problem occurs for soft ground in seismic areas. A reinforced concrete wall-frame dual framework's dynamic reaction to SSI has not been sufficiently studied and is infrequently taken into consideration in engineering practice. The structures’ seismic performance when SSI effects are taken into account is still unknown, and there are still some misconceptions about the SSI idea, especially regarding RC wall-frame dual systems. The simulation study of the soil beneath the foundations significantly impacts the framework's frequency response and dynamic properties. Therefore, the overall significance of SSI in the structural aspect and sustainability aspects will be reviewed in this research.

9

Vertical and horizontal dynamic response of suction caisson foundations

Bouneguet Soumia, Messioud Salah, Dias Daniel

Studia Geotechnica et Mechanica

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2023

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Vol. 45, nr 1

1--13

EN

In this article, the dynamic response of suction caisson foundations is studied using a three-dimensional finite element model with an absorbing boundary. The adopted formulation is based on the substructuring method. This formulation has been applied to analyze the effect of soil–structure interaction on the dynamic response of the suction foundation as a function of the kind of load. The suction caisson foundations are embedded in viscoelastic homogenous soils and subjected to external harmonic forces. For each frequency, the dynamic impedance connects the applied forces to the resulting displacement. The constitutive elements of the system are modeled using the finite element volumes and shell elements. The numerical results for the dynamic response of the suction foundations are presented in terms of vertical and horizontal displacements as well as vertical and horizontal dynamic impedances. The results indicated that the overall dynamic response is highly affected by the suction caisson diameter, the soil stiffness variation, and the suction caisson length.

10

Behaviour of soil-steel composite structures during construction and service: a review

Legese Alemu Mosisa, Sobótka Maciej, Machelski Czesław, Różański Adrian

Archives of Civil Engineering

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2023

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Vol. 69, nr 4

263--292

EN

In this paper, existing knowledge on the behaviour of soil-steel composite structures (SSCSs) has been reviewed. In particular, the response of buried corrugated steel plates (CSPs) to static, semistatic, and dynamic loads has been covered. Furthermore, the performance of SSCS under extreme loading, i.e., loading until failure, has been studied. To investigate the behaviour of the type of composite structures considered, numerous full-scale tests and numerical simulations have been conducted for both arched and box shapes of the shell. In addition, researchers have examined different span lengths and cover depths. Furthermore, to enhance the load-bearing capacity of the composite structures, various stiffening elements have been applied and tested. The review shows that the mechanical features of SSCSs are mainly based on the interaction of the shell with the soil backfill. The structures, as a composite system, become appropriately stiff when completely backfilled. For this reason, the construction phase corresponds to the highest values of shell displacement and stress. Moreover, the method of laying and compacting the backfill, as well as the thickness of the cover, has a significant impact on the behaviour of the structure at the stage of operation in both the quantitative and qualitative sense. Finally, a limited number of studies are conducted on the ultimate bearing capacity of large-span SSCS and various reinforcing methods. Considerably more works will need to be done on this topic. It applies to both full scale tests and numerical analysis.

PL

W artykule podsumowano dotychczasową wiedzę na temat zachowania się mostowych konstrukcji gruntowo-powłokowych. W szczególności przeprowadzony przegląd dotyczy mechanicznej odpowiedzi obiektów z blach falistych na obciążenia statyczne, quasi-statyczne i dynamiczne. Ponadto, studium literaturowe obejmuje badania konstrukcji gruntowo-powłokowych przy ich ekstremalnym obciążeniu, tj. do poziomu obciążenia niszczącego. W tym zakresie zachowanie rozpatrywanego typu konstrukcji badano w licznych testach obciążeniowych w pełnej skali jak również na drodze symulacji numerycznych zarówno dla kształtów łukowych, jak i skrzynkowych powłoki. Analizom takim poddano obiekty o różnych rozpiętościach I przy różnych grubościach zasypki. Ponadto, w celu zwiększenia nośności obiektów inżynierskich z blach falistych zastosowano i przetestowano różnego rodzaju elementy usztywniające. Z przeprowadzonego przeglądu wynika, że najważniejsze cechy mechanicznego zachowania się konstrukcji gruntowo-powłokowych opierają się głównie na wzajemnej współpracy powłoki z gruntową zasypką inżynierską. Obiekty takie, jako swego rodzaju układy zintegrowane, nabierają odpowiedniej sztywności dopiero po całkowitym zasypaniu powłoki. Z tego powodu największe deformacje oraz wytężenie powłoki występują w fazie budowy. Sposób układania i zagęszczania zasypki oraz jej minimalna wysokość ponad powłoką mają ponadto istotny wpływ na zachowanie się konstrukcji pod obciążeniem użytkowym na etapie eksploatacji, zarówno w sensie ilościowym, jak i jakościowym. Podsumowując przegląd, wskazano na fakt, że liczba badań, w których określano nośność graniczną, jest ograniczona w przypadku obiektów o dużej rozpiętości i przy zastosowaniu różnych sposobów wzmocnienia konstrukcji. W tym zakresie temat badań obiektów inżynierskich z blach falistych powinien zostać rozszerzony. W opinii autorów w najbliższych latach pojawią się nowe prace w tym zakresie. Dotyczy to zwłaszcza pełnoskalowych testów obciążeniowych ale także analiz numerycznych.

11

Modulus of Laterally Loaded Pile in Cohesionless Slope Crest with Varying Condition

Sivapriya Vijayasimhan, Ganesh Kumar Shanmugam

Civil and Environmental Engineering Reports

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2022

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Vol. 32, no. 3

133--142

EN

Soil - structure interaction behaviour of pile foundation is complex for heavier structures which suffer large lateral load due to wind, wave action etc., in addition to the large vertical and oblique load. The parameters involved in determining the lateral capacity of the foundation are its structural geometry, soil properties and ground condition. The behaviour is different for horizontal ground compared to the sloping ground; it is even different under loading and unloading conditions. In this study, the modulus of single pile is studied under various lengths, diameters, slope angles and loading directions. An equation is generated is developed to obtain the modulus with varying length and diameter.

12

Calculating the Dynamic Impedances of Foundations and their Effect on the Seismic Response of Structures: Analytical and Numerical Study

Boulkhiout Radhwane, Messast Salah

Civil and Environmental Engineering Reports

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2021

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Vol. 31, no. 2

178--217

EN

This study evaluates the movement of a frame built on soft soil under seismic excitation taking into account soil-structure interaction. First, the study was evaluated using the finite element method, then, by using a substructure method which modelled the soil using springs and dampers in a linear and nonlinear study. Rheological models were determined using impedance functions, calculated using a numerical program CONAN. These dynamic impedances are shown in the displacement vector of a three-degrees-of-freedom frame, which was calculated on the basis of lateral forces distributed over the structure height using the equivalent static method. In this regard, two different calculation norms were chosen; RPA2003 and UBC97. Finally, a parametric study was carried out, based on the effects of soil densification and the foundation geometry on the response of the RC frame.

13

A Study on Dynamic Behavior of Natural Draft Cooling Tower Considering the Effect of Soil-Structure Interaction

Chitrahalli Lingaraju Mahesh Kumar, Kotagi Girisha Shwetha, Bhaktanakatte Channabasappa Shanthappa, Karigowda Manjunatha

Civil and Environmental Engineering Reports

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2021

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Vol. 31, no. 4

17--32

EN

In this present era, the technology in advanced construction has developed to a very large extent. Some parts of the constructions are still in the improving stage which includes cooling tower construction. Hyperbolic cooling towers are large, thin shell reinforced concrete structures which contribute to power generation efficiency, reliability, and to environmental protection. Cooling towers use evaporation of water to eject heat from processes such as cooling the circulating water used in oil refineries and in power plants. Nowadays in many thermal power plants, we can see the cooling tower. So, preserving this industrial structure is an effort to save the cooling tower from dangerous earthquakes. The present-day cooling towers are exceptional structures in view of their sheer size and complexities. Present paper deals with the study of dynamic response that is modal analysis, seismic analysis of the two different cooling towers varying the H/t ratio and thicknesses with fixity at the base boundary condition, and the soil is modelled as raft for the effect of soil-structure interaction using the direct approach. In this paper, hyperbolic cooling towers are modelled using ANSYS software, which is a finite element software. Results show that the soil-structure interaction effect significantly modifies the earthquake behavior of hyperbolic cooling towers.

14

Accuracy assessment of linear elasticity solution for interaction of cylindrical tank with subsoil

Lewiński Paweł Marek

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 1

art. no. e136039

EN

The subject of this paper is an assessment of the accuracy of a solution based on the linear theory of elasticity describing the interaction of a cylindrical reinforced concrete tank with the subsoil. The subsoil was modelled in the form of an elastic half-space and Winkler springs. The behaviour of the shell structure of the RC cylindrical tank, and particularly of the ground slab interacting with the subsoil, depends largely on the distribution of the reactions on the foundation surface. An analysis of this structure with the shell fixed in a circular ground slab was carried out taking into consideration the elastic half-space model using the Gorbunov-Posadov approach and, for comparison, the two-parameter Winkler model. Although the results for both subsoil models proved to be divergent, the conclusions that follow the accuracy assessment of a solution based on the theory of elasticity are fairly important for engineering practice.

15

An application of reinforced concrete vaulted slabs and rafts in deep excavation works

Kacprzak Grzegorz, Daktera Tomasz, Stańczyk Andrzej, Tomczak Urszula, Bodus Seweryn, Werle Michał

Archives of Civil Engineering

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2021

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Vol. 67, nr 3

61--75

EN

The overall efficiency of a construction of a deep excavation urban project does not depend only on the duration of the construction but also on its influence on the urban environment and the traffic [9, 10]. These two things depend greatly on the excavation method and the construction stages defined during the design process. This paper describes the construction stages of three metro stations (two stations in Warsaw and one in Paris) and discusses their advantages and disadvantages including among other things its impact on neighbouring infrastructure and the city’s traffic. An important conclusion drawn from this analysis is that the shape of the slabs used can considerably affect the design and the construction stages. For example, a vaulted top slab allows an almost immediate traffic restoration and a vaulted bottom raft allows a much shorter dewatering period.

PL

Ogólna efektywność budowy miejskiej inwestycji głębokiego wykopu nie zależy tylko od czasu trwania budowy, ale także od jej wpływu na środowisko miejskie i ruch drogowy [9, 10]. Te dwie rzeczy zależą w dużej mierze od metody wykopów i etapów budowy określonych w procesie projektowania. W niniejszym opracowaniu opisano etapy budowy trzech stacji metra (dwóch w Warszawie i jednej w Paryżu) oraz omówiono ich zalety i wady, w tym m.in. wpływ na sąsiadującą infrastrukturę i ruch w mieście. Ważnym wnioskiem wynikającym z tej analizy jest to, że kształt zastosowanych płyt może mieć istotny wpływ na projekt i etapy budowy. Na przykład, górna płyta sklepiona pozwala na niemal natychmiastowe przywrócenie ruchu, a dolna płyta sklepiona pozwala na znacznie krótszy okres odwadniania. W rezultacie powstała bardziej globalna dyskusja na temat interakcji konstrukcji z gruntem, gdzie wykorzystywane są sklepione elementy konstrukcyjne. Gdy nacisk gruntu jest wywierany na sklepione górną płytę lub płytę denną, tworzenie się sił obręczowych w betonowych przekrojach poprzecznych pozwala na dodatkowe przenoszenie obciążeń i tym samym oferuje znaczne korzyści i szerokie możliwości projektowe.

16

Piles system securing road against landslide. 2D/3D method of numerical modeling and design problems

Urbański A., Grodecki M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2020

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Vol. 68, nr 6

1433--1442

EN

The main objective of this work is to present an innovative method of numerical modeling of anchored piles system acting as a road protection against landslide, called the “2D/3D method”. Firstly, short description of the problem and “state of the art” review are included. An effective methodology of the design supported by the numerical analysis, solving the problem of interaction of a periodic system of piles and the unstable soil mass is presented, for which some detailed information about proposed numerical approach is given. The key idea of 2D/3D method is to join the pile with the 2D plane strain continuum by fictitious connectors of Winkler type with P-Y properties identified during the analysis of a subsidiary 3D problem. Practical example of usage of proposed approach to a real case of a road endangered by a landslide then protected by the piles system is presented. On the base of this example, a discussion about important design issues like internal forces in piles (mainly bending moments) and anchors (tensile forces) or overall stability of the soil-structure system is done.

17

Soil-structure interaction of cylindrical tank of variable wall thickness under the constant thermal loading

Lewiński P. M., Rak M.

Archives of Civil Engineering

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2020

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Vol. 66, nr 4

269--285

EN

An effective method for the analysis of soil-structure interaction including the behaviour of cylindrical storage tank with varying wall thickness under the action of constant thermal loading is presented. Elastic half-space and the Winkler model have been used for the description of subsoil. The soil-structure interaction is described by using the power series. A computational example of reinforced concrete tank loaded with constant temperature is given. The analysis of a hydrostatically loaded cylindrical tank performed for the model incorporating elastic half-space shows decrease of radial displacements as well as substantial changes in the distribution of bending moments when compared to the Winkler foundation. Additionally, local increase of subsoil reaction around the slab circumference is observed for the case of elastic half-space, in contrast to the Winkler model. However, in the case of a tank loaded with constant temperature, the solutions for both subsoil models do not differ significantly.

PL

W pracy rozważana jest metoda obliczania naprężeń termicznych w zbiornikach cylindrycznych o zmiennej grubości ścianki, zamocowanych u podstawy w płycie dennej i poddanych osiowo-symetrycznemu równomiernemu obciążeniu termicznemu (rys. 1). Schemat wzajemnego oddziaływania konstrukcji z podłożem pozwala opisać zachowanie konstrukcji zbiorników kołowych o zmiennej grubości ścianki, stosując takie modele podłoża, jak półprzestrzeń idealnie sprężysta i model Winklera. Przyjęta tu metoda (por. Borowicka [1], Gorbunow-Posadow [4]) umożliwia analizę wzajemnego oddziaływania płyty dennej zbiornika z izotropową półprzestrzenią sprężystą obciążoną prostopadle na pewnym obszarze płaszczyzny granicznej, z uwzględnieniem równania różniczkowego opartej na niej płyty kołowej. Analizę współpracy konstrukcji z podłożem przeprowadzono metodą szeregów potegowych [11]. Zaletą tego podejścia jest jest stosunkowo prosty i dokładny opis wzajemnego oddziaływania konstrukcji z podłożem w porównaniu z innymi metodami.

18

Interaction of RC and PC cylindrical silos and tanks with subsoil

Lewiński P. M.

Archives of Civil Engineering

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2020

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Vol. 66, nr 4

249--267

EN

The subject of this paper is an analysis of the influence of circumferential prestressing on the interaction of cylindrical silos and tanks with the subsoil. The behaviour of the shell structures of RC and PC cylindrical silos or tanks (with circumferential pre-tensioning), and particularly of the ground slab interacting with subsoil, depends largely on the function graphs of the subsoil reactions on the foundation surface. Distributions of the subbase reactions on the ground slab in such structures as silos and tanks have a significant impact on the behaviour of not only the slab itself, but also the interacting shell structure. An analysis of these structures with walls fixed in a circular ground slab and foundation ring was carried out taking into consideration the elastic half-space model using the Gorbunov-Posadov approach and the two-parameter Winkler model. In the computational examples of RC and PC silos and tanks with walls fixed in the circular ground slab or foundation ring, the eventual effects of prestressing obtained as a result of the superposition of internal forces were examined. Although the results for both subsoil models proved to be divergent, the conclusions that follow are fairly important for the engineering practice.

PL

Przedmiotem niniejszej pracy jest analiza wpływu obwodowego sprężania na oddziaływanie silosów i zbiorników cylindrycznych z podłożem. Podłoże zamodelowano w postaci półprzestrzeni sprężystej i modelu Winklera. Zachowanie konstrukcji powłokowych żelbetowych i sprężonych silosów i zbiorników cylindrycznych, zwłaszcza płyt dennych oddziałujących z podłożem, zależy w dużej mierze od rozkładu reakcji podłoża na powierzchni fundamentu. Analizę tych konstrukcji ze ścianami zamocowanymi w kołowej płycie dennej i pierścieniu fundamentowym przeprowadzono z uwzględnieniem modelu półprzestrzeni sprężystej na podstawie metody Gorbunowa-Posadowa i dwuparametrowego modelu podłoża Winklera.

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Slurry shield tunneling in soft ground. Comparison between field data and 3D numerical simulation

Beghoul Mohammed, Demagh Rafik

Studia Geotechnica et Mechanica

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2019

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Vol. 41, nr 3

115--128

EN

In urban areas, the control of ground surface settlement is an important issue during shield tunnel-boring machine (TBM) tunneling. These ground movements are affected by many machine control parameters. In this article, a finite difference (FD) model is developed using Itasca FLAC-3D to numerically simulate the whole process of shield TBM tunneling. The model simulates important components of the mechanized excavation process including slurry pressure on the excavation face, shield conicity, installation of segmental lining, grout injection in the annular void, and grout consolidation. The analysis results from the proposed method are compared and discussed in terms of ground movements (both vertical and horizontal) with field measurements data. The results reveal that the proposed 3D simulation is sufficient and can reasonably reproduce all the operations achieved by the TBM. In fact, the results show that the TBM parameters can be controlled to have acceptable levels of surface settlement. In particular, it seems that moderate face pressure can reduce ground movement significantly and, most importantly, can prevent the occurrence of face-expected instability when the shield crosses very weak soil layers. The shield conicity has also an important effect on ground surface settlement, which can be partly compensated by the grout pressure during tail grouting. Finally, the injection pressure at the rear of the shield significantly reduces the vertical displacements at the crown of the tunnel and, therefore, reduces the settlement at the ground surface.

20

Effect of Tunnel Progress on the Settlement of Existing Piled Foundation

Al-Omari Raid Ramzi, Al-Soud Madhat Shakir, Al-Zuhairi Osamah Ibrahim

Studia Geotechnica et Mechanica

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2019

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Vol. 41, nr 2

102--113

EN

Tunnel construction below or adjacent to piles will affect the performance and eventually the stability of piles due to ground deformation resulting in the movement of piles and changes in the axial force distribution along the piles. A three dimensional finite element analysis using PLAXIS 3D (2013) was performed to study the behaviour of a single pile and 3 x 3 piles group during the advancement of shield tunnelling in ground. The 10-node tetrahedral elements were used to model both the soil and the tunnel lining. The Hardening Soil (HS) model was used to simulate the soil structure interaction at the tunnel-soil interface. An isotropic elastic model was used for the pile, piles cap, tunnel lining and tunnel boring machine shield (TBM). Several parametric studies were attempted including the longitudinal, lateral, and vertical tunnel location relative to pile embedded in different types of soil (clay or sand). The results showed that the pile head settlement increases during the tunnelling advancement in larger values than that for ground surface settlement. A zone of influence was determined in the range of twice the tunnel diameter in the longitudinal direction (forward and backward of the pile), and transverse direction (left and right of the tunnel centreline). If the tunnel boring is kept off this zone then there is no fear of pile collapse.