Zbigniew Zembaty

Zbigniew Zembaty
Opole University of Technology · Faculty of Civil Engineering

PhD, DrSc

About

85
Publications
11,398
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
934
Citations

Publications

Publications (85)
Article
Seismic vulnerability of speleothems may serve long-term seismic risk studies. For this reason, the seismic response of stalagmite is computed using a robust FEM model calibrated from free vibration records by Hilbert–Huang modal extraction. It is demonstrated that the stalagmite vibrations consist of pairs of closely coupled flexural natural modes...
Article
Full-text available
Measurements of rotations are unique because of their inherent property making them absolute and without an external frame of reference [...]
Article
Full-text available
Recent research in engineering seismology demonstrated that in addition to three translational seismic excitations along x , y and z axes, one should also consider rotational components about these axes when calculating design seismic loads for structures. The objective of this paper is to present the results of a seismic response numerical analysi...
Article
The application of rotation rate sensors in vibration-based damage detection is investigated. For this purpose, simulation, FEM analyses of a damaged cantilever plexiglass beam under kinematic excitations are carried out and verified experimentally. Three types of rotation rate sensors are examined. Damage index based on the maximum difference of s...
Article
Full-text available
Interest in measuring displacement gradients, such as rotation and strain, is growing in many areas of geophysical research. This results in an urgent demand for reliable and field-deployable instruments measuring these quantities. In order to further establish a high-quality standard for rotation and strain measurements in seismology, we organized...
Book
This book gathers a selection of papers presented at the 4th International Scientific Conference “Environmental Challenges in Civil Engineering”, ECCE 2020, , Opole, Poland, held on April 20-22, 2020, in Opole, Poland. The chapters, written by an international group of experts, report on advanced finding in structural material behaviour, and novel...
Article
Full-text available
The recent rapid development of rotation rate sensor technology opens new opportunities for their application in more and more fields. In this paper, the potential of rotational sensors for the modal analysis of full-scale civil engineering structural elements is experimentally examined. For this purpose, vibrations of two 6-m long beams made of ul...
Article
Full-text available
For decades, coal mining in the Upper Silesian Coal Basin (USCB) in Poland has been inducing annually more than 150 seismic events with local magnitude M > 2. Two sets of sensors were installed in the USCB in Poland to measure angular velocities and translational accelerations from seismic events induced by underground coal mining. In the period fr...
Conference Paper
Full-text available
The need to model seismic capacity of stalagmites derives from the objective of speleoseismology to study long term seismic hazard [1], [2], [3]. Assessment of the seismic capacity of stalagmites is done in terms of peak ground acceleration, which would break the stalagmite. The problem is not easy for many reasons: (1) the shape and internal struc...
Chapter
Soil-steel bridges and culverts, typically ranging from 3 to 25 m, can be used as an effective alternative for short-span bridges. They can meet the design and safety requirements of traditional bridges but at lower costs and with shorter erection time. For these reasons, soil-steel bridges are more and more often used in road and railway projects...
Chapter
Parametric analysis of the effect of soil compliance on the response of a slender tower to combined horizontal and rotational (rocking) of induced ground motion excitations is carried out. In contrast to earlier analyses which use theoretical decomposition of seismic wave field to obtain rotations, this study is using 6 degree of freedom ground mot...
Book
This book presents state-of-the-art knowledge on problems of the effects of structural irregularities on their seismic response. It also covers specific spatial and rotational seismic loads on these structures. Rapid progress in respective research on irregular structures and unconventional seismic loads requires prompt updates of the state of the...
Article
A problem of joint effects of a structural leaning and seismic excitations can be particularly important for tall buildings and slender towers. Present paper addresses problems of loss of seismic resistance of leaning tall structures on examples of two selected typical structures: a 160 m high industrial chimney and a slender 30-storey high buildin...
Article
Full-text available
Preliminary, numerical analyses of a novel Structural Health Monitoring (SHM) technique are reported. Based on recent developments of new rotation rate (rotation velocity) sensing devices, it is proposed to use the rotational sensors to measure the rotational difference of structural members to indicate plastic hinge development at the early stage....
Article
Two, the most intensive 6-dof ground motion records were selected from a database of a program of acquiring seismic aftershocks at Kefalonia Greek Island as reported by Perron et al. in 2018 [1]. The maximum Modified Mercalli (MM) intensity VII and peak ground velocity 18.4 cm/s reached during these seismic events made it possible to investigate su...
Article
Two records from 6-dof ground motion monitoring of induced seismic events are applied to study seismic response of a slender tower under horizontal-rotational excitations. The response of 160m reinforced concrete, industrial chimney is investigated under moderately intensive, simultaneously acting translational-horizontal and rocking components of...
Chapter
As induced seismicity from deep mining may cause quakes with a local magnitude of 4.5-5.5 and surface ground motion with Modified Mercali intensities up to VIII, such strong ground motions may result in serious damages to civil infrastructure. In the case of natural earthquake preparedness, seismic design codes are used to ensure that newly designe...
Article
This study investigated the application of rotation rate sensors to measure flexural vibrations of beams. This new area of the application of rotational sensors can be beneficial for monitoring various structures, particularly civil engineering structures like reinforced concrete beams and frames and masonry structures, which are difficult to asses...
Poster
Full-text available
The areas of intensive mining can be used as seismological test fields, to study strong ground motion effects. It is so because the magnitudes of induced mining seismic events may exceed 4 with return period of 3-5 years and the seismic events triggered at the nearby faults resemble shallow, natural earthquakes. Recently a ‘hot’ seismological subje...
Article
Surface rotational ground‐motion records that were collected by a network of deep mining exploration monitoring in the Polish region of the Upper Silesian Coal basin are reported. A set of 51 rotation records acquired during the first two months of the recording program is analyzed. The three strongest records are discussed in detail in this articl...
Conference Paper
Induced seismicity deep mining may cause quakes with local magnitude of 4.5 to 5.5 and surface ground motion with Modified Mercali intensities up to VIII. Such strong ground motions may result with serious damages in civil infrastructure. However to prepare any adaptation of classic seismic design codes to account for mine tremors faces a problem o...
Article
Full-text available
Starting with descriptions of rotational seismology, areas of interest and historical field measurements, the fundamental requirements for rotational seismometers for seismological and engineering application are formulated. On the above basis, a review of all existing rotational seismometers is presented with a description of the principles of the...
Article
Full-text available
This paper describes the experimental procedures and presents preliminary results of the international project entitled “High- Performance Composite-Reinforced Earthquake Resistant Buildings with Self-Aligning Capabilities”. The goal of the project was to increase our understanding of the seismic performance of woodlaminated frames with locally rei...
Article
The purpose of this paper is to present results of calculations of seismic response of the old Parma Bell Tower with and without the rotational, rocking seismic effects as modeled in the European seismic code: Eurocode 8 (part 6: Towers, Masts and Chimneys). A detailed, finite element model of the tower was prepared, which led to the solution of it...
Article
This paper presents a new approach to measure and monitor structural vibrations in civil and seismic engineering which uses new rotational sensors which can measure flexural vibrations of a beam axis. First a rotation rate sensor (measuring rotational velocity) is tested with respect to its ability to follow changes of strains in a beam during its...
Conference Paper
Full-text available
Deep mining may induce ground quakes with magnitude m L up to 5.5 and Modified Mercalli intensities up to VIII. This may cause serious damages in civil infrastructure in the vicinity of mines. Any adaptation of the seismic code to design structures subjected to mine tremors faces however an impending problem of differences in spectral content and d...
Conference Paper
Full-text available
The methods of vibration based, non-destructive damage evaluation, aiming at reconstructing stiffness distributions are particularly needed for structures, for which the localized damage is difficult to define. (e.g. reinforced concrete beams and frames). The newly developed rotation rate sensors may help in such formulated Structural Health Monito...
Article
This chapter presents the problem of deriving rotational ground motions (torsion about vertical axis and rocking about horizontal axis) from the wave decompositions of translational ground motions. Respective formulas for the torsional and rocking power spectral densities are formulated in terms of translational acceleration seismic components. The...
Article
This paper reports the analysis of the effectiveness of the application of rotation rate sensors in structural damage identification problem using harmonic vibrations for plexiglass models of cantilever beams. The two types of sensors are applied: angular rate sensors and conventional translational, piezoelectric accelerometers. The amplitudes of d...
Article
Full-text available
Preliminary results of an application of rotation rate sensors in dynamic identification of a vibrating beam are reported. Three rotational sensors, measuring the response of a cantilever beam to kinematic harmonic excitations are applied in the reconstruction of its stiffness. A successful reconstruction of 15% stiffness drops is demonstrated. Wit...
Data
Seismology is no longer based only on the analysis of observations made with classical seismometers measur-ing translational motions or their time derivatives. More and more observables like strain, rotations, GPS-based measurements and others are used to constrain either the Earth's structure or to understand the nature of seismic sources and obse...
Article
Full-text available
The paper presents preliminary results of shaking table tests of a wooden frame. The natural frequencies of the frame were identified from diagnostic, white noise excitations. A series of seismic tests with increasing intensity was carried out. The subsequent identification of natural frequencies of the frame has shown a decrease of natural frequen...
Article
Full-text available
Usually rockbursts from underground mining induce minor quakes of MM intensity up to V. Sometimes however the surface tremors reach level of MM epicentral intensity I 0=VI to VIII. Since a fast industrial development often takes place in the mining areas then some seismic design rules for new buildings are needed. The main obstacle is then lack of...
Article
This paper presents an analysis of stochastic eigenvalue problem of plane bar structures. Particular attention is paid to the effect of spatial variations of the flexural properties of the structure on the first four eigenvalues. The problem of spatial variations of the structure properties and their effect on the first four eigenvalues is analyzed...
Article
Recent progress in data acquisition technology makes it possible to measure not only translational but also angular vibrations of beam and frame structures. This raises a question whether these new methods can effectively be applied in damage structural detection and localization. For this purpose a damage detection method aiming at reconstructing...
Article
The paper by Agnieszka Krok and Zenon Waszczyszyn [Krok A, Waszczyszyn Z. Kalman filtering for neural prediction of response spectra from mining tremors. Computer Structure 2007;85:1257–63] is commented. The question of practical applicability of the acceleration response spectra of mining tremors is raised.
Article
A stiffness reconstruction method is tested when rotational degrees of freedom are added to the dynamic model of the structure. The inverse problem is formulated as a minimization problem in terms of harmonic vibrations of the structure and its finite element model. An example of frame structure is analyzed by numerical simulations. The results of...
Article
This article presents a concise review of the methods to obtain spectral densities of the rotational components of seismic ground motion from the spectral densities of both the translational components and wave propagation parameters. The rotational components are obtained by decomposing ground motion at the site into body and surface wave contribu...
Article
This note describes the rotational seismic load definition as included in Part 6 of Eurocode 8 (EC8.6, 2005). The Eurocode 8, Part 6 (EC8.6, 2005), definition of the rotational ground-motion component depends upon the structural subsoil compliance, which is controlled by the shear-wave velocity in the top 30 m of ground. A comparison of the effects...
Article
A damage detection method based on harmonic structural vibrations has been applied to reconstruct typical damage patterns of reinforced concrete beams and frames vibrating in three dimensions. It has been shown that comparison of harmonic vibrations of damaged and intact structures makes it possible to formulate optimization criterion which can be...
Article
Band-limited, non-stationary random vibrations of a shear beam are studied in order to investigate high frequency seismic effects on building structures. A solution for the evolutionary spectral density of the shear beam response to a time segment of band-limited white noise is given in a closed form. The root mean square (rms) and peak response of...
Article
A damage detection method based on harmonic structural vibrations has been applied to reconstruct realistic damage patterns of reinforced concrete beams. It was shown that the application of a hybrid method (genetic algorithm and Levenberg-Marquardt minimization technique) makes it possible to effectively reconstruct the flexural stiffness drops as...
Article
Formal extensions of the response spectrum method to include spatial seismic effects are reviewed. Two approaches are described in detail: the first based on random vibrations of a simple oscillator under two-component excitations, and the second analyzing multi-column building seismic response. The subjective choice of these two complementing appr...
Article
Dynamic eigenproblem of a beam resting on Vlasov's foundation has been analyzed by the Finite Element Method. While the beam properties were applied deterministic, the respective sub-soil parameters were assumed as random variables. Two specific cases of the stochastic description of the foundation of the beam were analyzed: one-dimensional, spatia...
Conference Paper
Each site on the surface of the ground can be subjected to six motions: three translations along x, y and z axes as well as three rotations about these axes. The rotation about vertical axis z is often called torsion while the rotations about two horizontal axes are called rocking. Particularly eventual presence of rocking components may lead to su...
Article
Full-text available
Two, full size, reinforced concrete frames were put on a shaking table and underwent seismic excitations with increasing intensities. The aim of the reported experiment was to study changes in their dynamic, modal parameters due to development of cracks in concrete. Dynamic identification of these frames was carried out through diagnostic tests int...
Chapter
Two engineering approaches for the analyses of the rotational component of surface seismic ground motion have been presented. Rocking component of ground motion about the horizontal axis was studied in detail. The first method is based on the decomposition of the ground motion into respective wave components and then differentiation with respect to...
Article
The purpose of this paper is to report selected results of an experiment in which two, natural size r/c frames were put on shaking table and subjected to a sequence of seismic excitations with increasing intensity interlaced with low level, diagnostic tests. The shaking table experiment aimed at working out new methodology for monitoring vibrations...
Article
While rockbursts from underground copper mining in Western Poland normally produce surface peak ground accelerations (PGA) and velocities of 0.05–0.1 g and 1–3 cm/s, occasionally these peak motions may exceed 0.15 g and 10 cm/s, respectively. These larger motions are of considerable concern and an investigation has been undertaken to define the nat...
Article
Stiffness of reinforced concrete (r/c) structures depend directly on the intensity of cracks which are accepted in many cases, even for sound r/c structures e.g. bridges. The loss of stiffness due to cracks for a r/c structure from intact state to damage may reach 40-60%. These changes of stiffness are reflected in the dynamic properties of the str...
Article
A simplified analysis of local site amplification effects on the seismic response of multi-support structures is presented. The site effects are modeled by considering reflections and transmission of vertically propagating shear waves from bedrock to the surface through a soil layer. A random vibration-based response spectrum of a simple oscillator...
Article
The paper is devoted to the investigation of seismic response of the masonry structure and describes experiences with modelling of boundary conditions during the test of large heavy model on 6DOF shaking table. The main aim of the research was how to increase dynamic resistance capacity of old masonry buildings including the medium and strong seism...
Article
Full-text available
A model of brick masonry building has been subjected to a series of excitations on shaking table. The paper presents results of identification of dynamic properties of the model from harmonic and seismic excitations by various methods: peak picking, animations of harmonic motion in resonance, half power bandwidth method, circle fit technique and fi...
Article
Full-text available
Results of an experimental project on seismic resistance of brick masonry buildings are presented in detail. After a short description of typical problems of the dynamic effects on brick masonry structures the details of a scaled (1:2), heavy (22 tons) model for testing on shaking table are discussed. The designed model has been theoretically model...
Article
The paper presents a numerical sensitivity study of the local site effects on structural response. Following a recently developed model of spatial coherency and a concept of a simple site coefficient the local site effects are modelled as filtrations of excitation processes with a frequency shift. An analysis of a bridge response with supports foun...
Article
Random vibrations of a bridge structure under propagating, seismic excitations are considered and joint effects of pseudostatic and dynamic vibrations are studied. Respective matrix equations of motion are derived. Detailed numerical analysis of a four-span bridge modeled as a three-dimensional (3D) frame under kinematic wave excitations with an ob...
Article
When selecting the earthquake design specification, for a given translation ground motion, the spatial variation of the motion has often been investigated as a possible source of further excitation for certain structures of large dimensions. It can be defined by the ‘rotation response spectrum’, or the ‘rotation power spectrum’. Previous evaluation...
Article
Dynamic coefficients in the format of response spectra are analyzed as simplified measures of spatial seismic effects on structures. The coefficients are formulated as dynamic response ratios in terms of point spectral density and unlagged coherency of excitations as well as frequency response function of an oscillator. The displacement ratio stays...
Article
The paper presents a matrix formulation of linear response of discrete dynamic systems to propagating random excitations. Combined effects of pseudo-static and dynamic responses are considered. Characteristic features of displacement and force response are pointed out. Direct and mode superposition methods, respectively, are considered. A practical...
Chapter
The problem of vibrations of structures under incoherent or, in particular, propagating excitations is important for large, extended civil engineering structures like bridges, lifelines, dams, offshore structures or for aircraft structures. In seismic engineering spatial ground motion models have been studied for more than a decade but credible, st...
Article
Full-text available
In this paper, a stochastic analysis of surface rotations during earthquakes is presented. The surface motion is modeled by a spacetime random field. A method to obtain rotation based on direct differentiation of the random field is proposed with a reference to a second method based on wave decomposition. The first method leads to a spectral densit...
Article
An algorithm for the spectrum of the rotational component of surface ground motion during earthquake is derived. To obtain the rotation the total motion is decomposed into the wave components. Then the rotational motion is obtained in terms of the horizontal and vertical components treated as non-stationary random processes. The evolutionary spectr...
Article
Full-text available
A random-vibration-based force-response spectrum of a simple oscillating frame is proposed as a simplified measure of the effect of spatial seismic excitations on structures. Such a response spectrum reflects the effect of incoherent support motions on quasi-static and dynamic response of structures. The response spectrum is formulated as a dynamic...
Chapter
The problem of reliability of structures under dynamic random loads has been a subject of considerable research in the last 20 years. Most of the research has been devoted to two general approaches: cumulative damage (fatigue failure) and first passage failures of structures. The latter approach deals usually with one dimensional problems and consi...
Article
An analysis of the influence of strong motion duration on the response spectra is presented. The analysis is based on the concept of evolutionary power spectral density and first passage estimations for non-stationary random vibrations. To compare the response for different durations the criteria of constant Arias intensity and constant excitation...
Article
This paper considers the problem of random vibrations and the reliability of slender tower-shaped structures subjected to seismic excitations. Applying the concept of evolutionary spectra and the uniformly modulated random process as a model of strong ground motion, the response statistics are derived. Peak response values and reliability are then...
Article
A matrix formulation of the dynamic response of multidegree-of-freedom systems to unsteady random citations is presented. The analysis is based on an orthogonal representation of unsteady random processes first introduced by Priestley. The matrix equations relating input and output are derived. Examples of the calculation of the evolutionary spectr...
Article
Full-text available
The paper will present fundamentals of the implementation of stochastic approach into the classic decomposition of rocking ground motion (about horizontal axis). For this purpose a Stieltjes-Fourier spectral decomposition of stochastic process will be applied. To cover the necessary evolution of the ground motion in time and frequency domains the P...
Article
Full-text available
In present paper selected results of a study of non-stationary random vibrations of a shear beam excited by time segments of band limited white noise are presented. The root mean square (rms) and peak response of the shear beam is studied for two characteristic frequency bands: the conventional 1-4Hz and higher frequency 4-16Hz, characteristic for...
Article
Two earthquakes, with the magnitudes of about 5,3 and 4,7 in the Richter scale took place in Poland in 2004. The description of these seismic events as well as the evaluation of their intensities and influence on structures have been discussed in the present paper.
Article
Year 2010 marks the beginning of the process of implementation of Eurocodes in the EU states. This includes also the Eurocode 8 dealing with seismic effects on structures. A wide scale verification of the European seismic risk revealed a minor and moderate seismic risk for Slovakia, Czech Republic and Southern Poland. The paper considers whether al...
Article
Full-text available
The paper presents a Eurocode 8 based concept of the design response spectrum for the Lubin-Glogow Copper Mine Basin. The unique feature of the proposed approach it is linking of the the so called design acceleration with the forecasted horizontal, peak ground velocity defined for specific surface zone of mine exploitation. Peak horizontal velocity...

Network

Cited By