The present article relates to the subject of the relocation of buildings. It presents a historical background of operations of this type carried out in the past around the world, as well as in Poland. It goes on to discuss in more detail some pioneering structural and technological solutions used during the relocation of the Rogatka Grochowska (Grochowska tollgate) building, carried out in 1961 in Warsaw. The article’s main theme is the process of relocation of a historic building No. 15 within the old Norblin Factory in Warsaw, which took place during the final months of 2018. The article briefly presents the factory’s history. It also describes the assumptions of the related project, which covers the development of the old Norblin Factory. It discusses in detail the concept and the scope of the relocation of building No. 15, with the description of the structural and technical design related to this process. The progress of the relocation which took place in 2018 has been reported in detail.
This paper compares the measurement results of dynamic characteristics, including natural frequencies, damping ratio, and wind-induced responses of the Stuttgart TV Tower (TV Tower), obtained by Lenk in 1959 using classical instruments with those obtained by the authors a few decades later using Global Positioning System (GPS). The objective of this paper was to monitor the response of the TV Tower under wind loading, which is an important tool for the validation of its design, construction, and structural health. During the authors’ GPS measurements, weak and moderate wind speeds occurred most of the time. Only in 2007, the stronger wind observed (90 < V < 100 km/h) at the head of the TV Tower (H=157 m), which caused displacements in the decimetre range. Further measurements in 2011 were carried out, using additional GPS receivers with a higher data rate. The results achieved by the GPS prove that the cross-wind response was larger than the along-wind component for all ranges of wind speed, which occurred during the measurement periods, i.e. from 2002 to 2015. The authors of this paper extended Lenk’s results, by the static and along-wind components, confirmed the first natural frequency, and damping ratio, evaluated by the Random Decrement technique. Mounting a GPS receiver, on the steel antenna mast tip, enabled detection of the second natural frequency fs2 = 0.800 Hz, which is the frequency of the mode shape of the TV Tower steel antenna mast. Lenk did not measure this frequency.
Numerical analysis of robustness assessment of steel planar framed structures under sudden external column removal is presented. The analysis is based on the previous experimental and numerical analyzes conducted in the Ph.D. project.Advanced and validated finite element models of steel structures with bolted end plate joints were used using Abaqus software. Six different cases of analysis using flush and extended bolted end-plate joints were performed. The actual results of the axial forces and rotations of the joints, failure models, and other important factors about structure behaviour are presented. The clear division of the results obtained depended on the type of joint used in the structure. In the cases of application of extended end-plate joints in frame analysis, the required level of robustness was reached in all cases and stopping of collapse development was obtained. In all cases of frame analysis with flush end-plate joints, an insufficient level of robustness on progressive collapse was obtained and partial failures of the structures were reached. Due to the location of the external column, the catenary actions to mitigate progressive collapse were very limited.
In this study, the uniaxial compression test and PFC 2D numerical simulation were carried out on the artificial rock specimen with T-shaped prefabricated fractures. The effects of the lengths l1, l2 of the main fractures, the length l3 of the secondary fracture, and the angle β between the secondary fracture and the loading direction on the uniaxial compressive strength and crack evolution law of specimen were studied. The research results show that the change of l1, l2 and β has obvious effect on the compressive strength and crack growth of the specimen, but the change of l3 has little effect on the compressive strength of the specimen. When l3 = 40 mm and l1 ≠ l2, the angle β influences on the crack propagation and failure mode of the specimen.
The purpose of the following paper is to present the experimental field investigations in jointless railway track subjected to the author’s generated imperfections on its static work. The main concept for the executed investigations is to induce an intentional imperfection (both a concave and convex irregularity) in an actual railway track, propose a way of appropriate measurement (using the PONTOS system), and utilize author’s field investigations results to calibrate necessary parameters for theoretical calculations. An experimental formula describing the value of the force transferred from the rail to the railway sleeper on the grounds of the survey site caused by a locomotive is provided. Furthermore, the deflection of the chosen railway rail and sleeper due to the generated imperfection is subjected to analysis. Finally the objective of the present consideration is to resolve the calculations into the beam element such that the results can be used in computational railway practice. The scheme of the so-called a “hanging sleeper” is particularly unfavourable, a gap arises between the sleeper and the foundation, for which the significant changes appear, especially in the rail deflections and stresses. A work scheme of the railway track elements is described on the generated short concave and convex irregularity.
Poznan University of Technology, Faculty of Civil and Transport Engineering, Institute of Civil Engineering, Division of Bridges and Railway Engineering, ul. Piotrowo 5, 60-965 Poznań, Poland
Unlike in conventional bridges, the backfill and the roadway pavement have a major bearing on the load capacity of buried corrugated metal structures. In the soil-steel structure model one can distinguish two structural subsystems: the shell made of corrugated steel plates and the soil backfill with the road pavement. The interaction between them is modelled as a contact (interfacial) interaction, i.e. forces normal and tangent to the surface of the shell. The normal interactions are variable during both construction and service life. Two algorithms are presented. In the first algorithm on the basis of unit strains the internal forces in the shell are determined and consequently the contact interactions are calculated. A large number of measuring points distributed on the circumferential section of the shell is needed for the calculations. In the second algorithm the collocation condition, according to which the result obtained from the shell geometry model must agree with the measured displacement of the structure’s collocation point, is used. When there are more such points, the estimated result is more precise. The advantage of both algorithms is that they take into account the physical characteristics of the soil in the backfill layers, but above all the backfill laying and compacting technology. The results of such analyses can be the basis for comparing the effectiveness of conventional geotechnical models.
Perforated sheets are materials which – maintaining good mechanical properties – are characterized by reduced mass in comparison to full sheets. Their elastic properties are important features that are considered in the context of these materials’ design applications. Compared to full sheets, they are characterized by reduced mass while simultaneously preserving good strength properties. This article presents an experimental and numerical analysis of the effect of key parameters of the hole mesh (open area, hole diameter and orientation relative to the direction of greatest hole concentration) in association with the type of material and sheet thickness �� on the value of the effective Young’s modulus of perforated sheet. A significant influence of open area (the share of holes in the sheet, as a percentage) and orientation angle was determined. On the basis of experimental results and computer simulations, a mathematical dependency allowing for calculation of this parameter’s valuewas proposed. The average deviation of calculated values from experimental is less than 4%.
It is the foundation of tunnel engineering to classify the rock mass surrounding tunnels. However, it is not easy to precisely determine the class of rock mass in practice as sufficient geological exploration need to be completed before rock mass classification, and there exists some disputes referring to the rationalization of dozens of methods for rock mass classification through the world. The principles and procedures of the basic quality method, which are widely used in China, are presented in this paper, and the application process of the basic quality method is showed with a project case of Zhongnanshan highway tunnel which has operated in safety for nearly a decade. Then, both the advantages and disadvantages of the basic quality method are analyzed in terms of practical engineering applications. In consideration of the defects of the basic quality method, the concept of the subclassing of surrounding rock in grade III–V is developed in the end and the criterion is given to determine the subclass of rock mass. This study is aimed at providing some useful ideas and a reference for rock classification in highway tunnel engineering.
Construction objects must be protected not only at the stage of their construction, but also during exploitation. Particular attention should be paid to objects included in the list of monuments. The Act on the Protection of Monuments and the Guardianship of Monuments states that any building that is important for history and science can become a heritage building and should therefore be preserved. The aim of this article was to improve the method of visual assessment of the technical condition of heritage buildings with the use of fuzzy logic. The improved method is to facilitate the comparison of assessments of the technical condition of a building performed at intervals specified in the regulations, often by different people. The research was conducted on the basis of technical expertise prepared for five examined buildings that were tenement houses entered in the register of monuments. The use of the visual method provides for the assessment of individual elements of the object by an expert and a verbal description of the elements using a five-point scale. A significant limitation of this method is uncertainty associated with the exact ranges of the acceptable values, as these ranges are subjective and depend on the opinion of an evaluator. The impact of this limitation can be reduced by applying fuzzy logic. In the fuzzy logic model, as input variables the following were applied; assessments of the technical condition of individual elements of the object (underground structure, load-bearing walls, ceilings, roof, other elements) and an integral indicator of the technical condition of the entire historic object, calculated as the output value.
The speed of test vehicles on the high-speed car track of the automobile test field is very high. Reducing the construction error of asphalt pavement is very important to ensure the safety of the test vehicle. In order to realize the paving of asphalt concrete pavement with super-large lateral inclination in the curve section of the high-speed car track in the automobile test field, a special paving control device and control method for the construction on the curve section with super-large lateral inclination were developed. Use the direction of the hanging hammer under the GPS device of paver to adjust the position of GPS device in real time, so that the geometric centre line of GPS device is always perpendicular to the horizontal plane. The reference control line is preset in the paver operation control device, and the lateral displacement deviation of the paver is adjusted to synchronize the data of the paver control device with the travel route. The precise control of the paver’s forward route is realized, the construction precision of the super-large inclined asphalt pavement on the high-speed car track of the automobile test field is achieved, and the construction efficiency is greatly improved. It has important reference value for similar projects such as automobile testing field and racing track.
The article presents and describes the methodology of the conservation of stone structures that are architectural monuments discovered as part of the work carried out during archaeological excavations in Tanais. The authors’ experiences presented in the article result from many years of cooperation between the Faculty of Civil Engineering at Warsaw University of Technology and the Antiquity of Southeastern Europe Research Centre at the University ofWarsaw. Examples of preserved masonry structures come from an excavation in Tanais near Rostov-on-Don. Works on stone structures located in the area of archaeological excavation are characterised by a unique specificity covering both formal issues, resulting from international standards and agreements regulating the conservation of historic buildings, as well as technical and environmental issues. The primary technical issues include ensuring the safety of further excavation works, protection of masonry structures against the destructive effects of atmospheric conditions and preparing the structure for possible exhibition in archaeological parks organized on the site of excavations. The article presents the procedures that should be used to conserve this type of structure and the specific sustainable technological and material solutions used in the shown objects.
Balconies are elements of some multi-storey buildings. Thermo-insulated fasteners are components that connect balcony slabs with the building structure. Their main task is the transfer of loads in connections of balcony slabs with the building while also minimizing thermal bridges. The article presents analytical calculations performed to develop the new type of thermal insulated fasteners and to determine their load-bearing capacity. The aim of this article is to demonstrate that analytical calculations based on commonly utilized principles of reinforced concrete and steel structure operation along enable the development of the effective design algorithm of insulated fasteners and allow for a quick analysis of various geometric variants of these fasteners. The article presents the adaptation of typical algorithms for calculation of steel and reinforced concrete structures for the analysis of non-typical load-bearing capacity states that occur during the calculation of insulated fasteners. The load-bearing capacities of individual fasteners are shown in M-V interaction diagrams (bending moment – shearing force).
Bydgoszcz University of Science and Technology, Faculty of Civil and Environmental Engineering and Architecture, Al. prof. S. Kaliskiego 7, 85-796 Bydgoszcz, Poland
Glass is a material commonly used in construction. The development of technology related to it, and the increase in knowledge concerning its mechanical and strength properties offer opportunities for glass to be applied as a structural material. The advancement in glass structures, methods for their design, as well as guidelines and standards in this fields are being developed in parallel. This article describes the main assumptions contained in the German TRxV guidelines, the series of German DIN 18008 standards, and the European EN 16612, and EN 16613 standard. Moreover, the following article presents the concept of structural glass design included in the draft pre-standard prCEN/TS 19100, which provides the basis for the formulation of the European standard Eurocode 10. According to this pre-standard, structural elements of glass will be verified in four limit states, depending on the Limit State Scenario (LSS). Apart from the classic limit states, i.e., the ultimate limit state (ULS), and the serviceability limit state (SLS), it is also assumed to introduce a fracture limit state (FLS), and postfracture limit state (PFLS). The article also addresses the issue of laminated glass working in structural elements. Depending on the coupling between the glass panes and the polymer or ionomer interlayers, laminated glass can be divided into complete coupled or uncoupled, and can work in intermediate situations. The methods for determining the effective thickness contained in European standards and guidelines are discussed in this article.
Damage occurring on a reinforced concrete beam (e.g. spalling) can reduce beam’s capacity to withstand external loads. The damage becomes more critical if it is occurred in the shear span since it may lead to shear failure. Patching to the damage zone by suitable patch repair material could be the best option in restoring the shear capacity of the beam. This research investigates the shear recovery of patched reinforced concrete beams with web reinforcement. The patching material used is unsaturated polyester resin mortar. The shear recovery is assessed on the basis of the patched beam’s behavior under flexure-shear load in comparison with those of normal beams. The behavior observed include cracking failure mode, strains of the reinforcements, and load-deflection behavior. The results indicate that the UPR mortar is capable to restore the strength of the damage reinforced concrete beam. The characteristic of UPR mortar (low elastic modulus and high strength) can be the origin of the overall behavior of the patched reinforced concrete beams.
Elastic lateral-torsional buckling of double-tee section structural steelworks has been widely investigated with regard to the major axis bending of single structural elements as a result of certain loading conditions. No specific attention has been paid to the general formulation in which an arbitrary span load pattern was associated with unequal end moments as a result of the moment distribution between structural members of the load bearing system.Anumber of analytical solutionswere developed on the basis of the Vlasov theory of thin-walled members. Since the accurate closed-form solutions of lateral-torsional buckling (LTB) of beams may only be obtained for simple loading and boundary conditions, more complex situations are treated nowadays by using numerical finite element methods (FEM). Analytical and numerical methods are frequently combined for the purpose of: a) verification of approximate analytical formulae or b) presentation the results in the form of multiple curve nomograms to be used in design practice. Investigations presented in this paper deal with the energy method applied to LTB of any complex loading condition of elements of simple end boundary conditions, bent about the major axis. Firstly, a brief summary of the second-order based energy equation dealt with in this paper is presented and followed by its approximate solution using the so-called refined energy method that in the case of LTB coincides with the Timoshenko’s energy refinement. As a result, the LTB energy equation shape functions of twist rotation and minor axis displacement are chosen such that they cover both the symmetric and antisymmetric lateral-torsional buckling modes. The latter modes are chosen in relation to two lowest LTB eigenmodes of beams under uniform major axis bending. Finally, the explicit form of the general solution is presented as being dependent upon the dimensionless bending moment equations for symmetric and antisymmetric components, and the in-span loads. Solutions based on the present investigations are compared for selected loading conditions with those obtained in the previous studies and verified with use of the LTBeam software. Conclusions are drawn with regard to the application of obtained closed-form solutions in engineering practice.
The non-linear analysis of hollow-core concrete slabs requires the use of advanced numerical techniques, proper constitutive models both for concrete and steel as well as particular computational skills. If prestressing, cracking, crack opening, material softening, etc. are also to be taken into account, then the computational task can far exceed the capabilities of an ordinary engineer. In order for the calculations to be carried out in a traditional design office, simplified calculation methods are needed. They should be based on the linear finite element (FE) method with a simple approach that takes into account material nonlinearities. In this paper the simplified analysis of hollow-core slabs based on the generalized nonlinear constitutive law is presented. In the proposed method a simple decomposition of the traditional iterative linear finite element analysis and the non-linear algebraic analysis of the plate cross-section is used. Through independent analysis of the plate cross-section in different deformation states, a degraded plate stiffness can be obtained, which allows for iterative update of displacements and rotations in the nodes of the FE model. Which in turn allows to update the deformation state and then correct translations and rotations in the nodes again. The results obtained from the full detailed 3D nonlinear FEM model and from the proposed approach are compared for different slab cross-sections. The obtained results from both models are consistent.
Mechanical properties of FRP such as strength and stiffness as well as the bonding interface between FRP and concrete will be badly deteriorated when exposed to high temperature. Furthermore, the effect of thickness of insulation with different type of concrete strength has not yet been studied elsewhere in numerical studies. Therefore, this study is to assess the thermal-structural behaviour of insulated FRP strengthened RC beam exposed to elevated temperature using ABAQUS. The proposed numerical model of 200 ×300 mm RC beam subjected to 2 hours standard fire curve (ISO 834) had been validated with the analytical solution. The validated numerical model then is used in parametric study to investigate the behaviour of fire damaged normal strength concrete (40 MPa) and high strength concrete (60 MPa) of RC beam strengthened with CFRP using various fire insulation thickness of 12.5 mm, 25 mm and 40 mm, respectively. The result of steel characteristic strength reduction factor is compared with analytical using 500˚C Isotherm methods. The parametric studies indicated that the fire insulation layer is essential to provide fire protection to the CFRP strengthened RC beams when exposed to elevated temperature. The insulation layer thickness of 25 mm had been found to be the optimum thickness to be used as it is able to meet the criteria of temperature distribution and displacement requirement. In conclusion, the numerical model developed using ABAQUS in this study is to carry out assessment on the thermal-structural behaviour of the insulated CFRP-strengthened RC beams at elevated temperature.
Public Work Department, Jalan Sultan Salahuddin, 50582 Kuala Lumpur, Malaysia
School of Civil Engineering, University Teknologi Malaysia, 81310 Skudai, Johor Bahru, Johor, Malaysia
Institute of Noise and Vibration, University Teknologi Malaysia, 81310 Skudai, Johor Bahru, Johor, Malaysia
Candidate, School of Civil Engineering, University Teknologi Malaysia, 81310 Skudai, Johor Bahru, Johor, Malaysia
Engineering Seismology and Earthquake Engineering Research (eSEER), Institute of Noise and Vibration, Universiti Teknologi Malaysia, 81310 Skudai, Johor Bahru, Johor, Malaysia
The problem of the arch barrel deformation in railway backfilled arch bridges caused by their typical service loads is analysed. The main attention is paid to vertical or radial displacements of characteristic points of the arch barrel. In the study results of deflection measurements carried out on single and multi-span backfilled arch bridges made of bricks or plain concrete during passages of various typical railway vehicles are used. On the basis of such results empirical influence functions of displacements are being created. In the next step, the results are utilised to estimate bending effects within the arch. The paper includes different procedures based on measurements of displacements in various points and directions. Using empirical influence functions arbitrary virtual load cases may be also considered. In this manner the proposed methodology shows a potential to be an effective tool of comprehensive calibration of numerical models of backfilled arch bridges on the basic of field tests carried out under any live loads.
The transport system is considered the “backbone” of the urban development. Along with the rapid economic development, the urban road transport system is being paid attention and invested by Hanoi city. By the year 2050, The Hanoi municipal government is expected to complete and hand over for use about 317 urban road transport projects. Due to the high demands of social and economic efficiency, the urban road transport projects in Hanoi face many risks. In which, there are 13 high dangerous risks for the urban road transport project in Hanoi. These risks have the high probability and severity impacted on the outcome of the projects. The project participant’s risk management standpoint will determine the solutions to respond the respective risks, thereby affecting the results of the project. In this paper, the authors compare the risk management standpoint of three main project participants, including owner/project management board, consultant and main contractor/subcontractor. The difference of the risk management standpoint is shown clearly by the project participants’ assessments of 13 high dangerous risks.
This research paper presents the results of the analyses of the course of technical wear over time carried out for residential masonry buildings located in the mining area of the Lublin Coal Basin (LCB). As a result of the conducted analyses, models of the course of technical wear over time were obtained for the entire building development and for groups of buildings, taking into account the conducted renovation works and preventive structural protection. By comparing the parameters of the developed models, statistically significant differences in the course of technical wear resulting from the quality of maintenance and the use of preventive measures were identified. In addition, the durability of individual groups of structures was estimated and compared. Based on a comparison of the course of technical wear of 22-year-old building structures, unrenovated and with similar structural and material solutions, it was found that the rate of increase in technical wear after 50 years of use is on average 3.5% lower than in the case of unprotected buildings. In addition, the use of preventive structural protection extends the durability of the analysed building structures by an average of over 13 years. The obtained results may e.g. help owners or managers optimise the Maintenance Management of building structures.
The hydraulic fill method of erecting dams was characterized. The main assumptions and practical aspects of sand spigot were discussed on the example of the spigot of the dam body of the Zelazny Most Tailings Storage Facility (TSF). The advantages and disadvantages of the method are discussed, and the directions of attempts to implement pipelines rising along with sedimenting waste are presented, which are to reduce earthworks.
In this work, the instability damage modes of yield state of a steel tube at the tension side of a rectangular steel tube-confined concrete (RCFST) column under eccentric compression were classified into two types based on the coupling effect of slenderness ratio (λ) and eccentricity ratio (γ). The two types include the unilateral compression yield failure mode with a smaller value of γ and tensile and compressive yield failure modes on both column sides with a larger value of γ. Further, the parametric analyses were performed by employing the finite element (FE) method and the analytical analysis to test 16 groups of RCFST columns by varying the γ value with different λ values. It was observed that the results of the analysis for the mechanical properties like the responses of load-strain ( P-ε) and RCFST column instability modes correlated well with the results obtained in the experiments. Furthermore, the proposed theoretical method could be used to investigate the roles of γ as a controller against the instability in RCFST columns when compared with λ.
In Eurocode 5, the stiffness equation for bolted steel-wood-steel is stated as a function ofwood density and fastener diameter only. In this research, an experimental study on various configurations of tested bolted steel-wood-steel (SWS) connections has been undertaken to predict the initial stiffness of each connection. In order to validate the Eurocode 5 stiffness equation, tests on 50 timber specimens (40 glued laminated timbers and 10 laminated veneer lumbers (LVL)) with steel plates were undertaken. The number of bolts was kept similar and the connector diameter, timber thickness, and wood density were varied. The results obtained in the experimental tests are compared with those obtained from the Eurocode 5 stiffness equation. From the analysis, it is signified that the stiffness equation specified in Eurocode 5 for bolted SWS connections does not adequately predict the initial stiffness. The results from Eurocode 5 stiffness equation are very far from the experimental values. The ratio of stiffness equation to experimental results ranges from 3.48 to 4.20, with the average at 3.77, where the equation overpredicted the experimental stiffness value for the connection. There is a need to consider or incorporated other parameters such as geometric configurations in Eurocode 5 stiffness equation to improve the ratio with the experimental data.
University Malaysia Perlis, Faculty of Civil Engineering Technology, 02600 Arau Perlis, Malaysia
2Sustainable Environment Research Group (SERG), Centre of Excellence Geopolymer and Green Technology (CEGeoGTech), University Malaysia Perlis (UniMAP), 01000 Kangar Perlis, Malaysia
University of Auckland, Faculty of Civil Engineering, Department of Civil and Environmental Engineering, Auckland, New Zealand
Department of Civil Engineering, College of Engineering, University Malaysia Pahang, 26300 Gambang Kuantan, Pahang Malaysia
Czestochowa University of Technology, Czestochowa, Poland
Centre of Excellence Geopolymer and Green Technology (CEGeoGTech), University Malaysia Perlis (UniMAP), 01000 Kangar Perlis, Malaysia
Sustainable Environment Research Group (SERG), Centre of Excellence Geopolymer and Green Technology (CEGeoGTech), University Malaysia Perlis (UniMAP), 01000 Kangar Perlis, Malaysia
University Malaysia Perlis, Faculty of Chemical Engineering Technology, 02600 Arau Perlis, Malaysia
Division of Materials Processing Technology and Computer Techniques in Materials Science, Silesian University of Technology, 44-100 Gliwice, Poland
en
pl
