The structural changes of interfacial transition zone of two concrete systems reinforced by polyp... more The structural changes of interfacial transition zone of two concrete systems reinforced by polypropylene/polyethylene and basalt fibers were studied by Raman microspectroscopy. The interfacial transition zone was found in the 0-20 µm in vicinity of quartz/feldspar aggregate surface. The calcium carbonate, ettringite and alite and belite bands were used for determination of interfacional transition zone size by Raman spectroscopy. Similar behaviour has been shown the cement matrix in neighbourhood of PP/PE fibers. There is not observed any concentration gradient of cement hydration product in the vicinity of 1 µm diameter basalt fiber.
The Churches of the Broumov region are well known for their unique baroque architecture, distinct... more The Churches of the Broumov region are well known for their unique baroque architecture, distinct shapes, sizes, and constitutes an integral part of the Czech cultural heritage. The St. Barbara’s Church that has been studied in this article, is in the Otovice village of Broumov. It was built in the year 1726 by Bavarian architects Christoph Dientzenhofer and Kilian Ignaz and is significant because of its religious, artistic and historic values. The main objective of this study is to evaluate the structural safety and stability of St. Barbara’s Church based on a probabilistic approach. A deterministic assessment of the structure is carried out and the results are assessed concerning the present site condition. Depending upon the observed damages, a condition for failure is defined for the structure. The uncertainties in the material parameters are considered and reliability analysis is performed to determine the reliability index, probability of failure and influence of different mat...
Proceedings of the 22nd Conference on the Rehabilitation and Reconstruction of Buildings
The churches of the Broumov region are renowned for their unique baroque architecture, their dist... more The churches of the Broumov region are renowned for their unique baroque architecture, their distinct shapes, and sizes. They are an integral part of the Czech cultural heritage. If you analyze the churches, it becomes evident that both the local geological conditions and the municipal economic situation have played an important role in their current condition. Moreover, the local construction industry has been significantly affected by historical events. In this article we would like to present the effects of those factors on the current state of selected churches, namely on the bearing capacity of their walls. Besides being very interesting, it also plays a key role in the maintenance and the potential reconstruction of the churches.
Broumov Region and its group of churches represent a perfect example of symbiosis between Baroque... more Broumov Region and its group of churches represent a perfect example of symbiosis between Baroque architecture and countryside landscape. This peculiar heritage site requires specialized analysis to preserve its uniqueness. St. Barbara Church in Otovice, the one investigated in this thesis, was built by Christoph and Kilian Dientzenhofer. Nowadays, concerns about its stability and degradation process led to the necessity to investigate more deeply its current condition. Therefore, the main objective of the article consists in the FEM modeling and the evaluation of the bearing capacity of enclosure walls, with particular attention on the influence of the soil deterioration. In conclusion, technical advices are recommended.
The paper shows numerical investigation of decay and damage appearing in the All Saints church, w... more The paper shows numerical investigation of decay and damage appearing in the All Saints church, which was selected from the Broumov group of churches. The study has been started off by summary of findings from preliminary historical, geotechnical background studies. Several conclusions of possible sources of decay and damage of the church were made. The most important sources include presence of moisture and possible differential soil settlement as a result of uneven deterioration of subsoil. In order to investigate the extent of damage series of FEM modeling was employed.
The known solution of isotropic elastic layer was modified for orthotropic elastic material behav... more The known solution of isotropic elastic layer was modified for orthotropic elastic material behavior in this contribution. The solution was original derived for calculation of footing settlement. However it should be useful for estimation of orthotropic material parameters. Timber is classical orthotropic material. Timber board which is placed on the rigid basement it could be considered as the elastic layer. From the known load displacement curve we can, vice versa, estimate the material parameters. The present solution should be able to control loading by rigid strip footing acting perpendicular to the plane of orthotropy. The contribution summarize the first steps of the proposed back analysis.
Wood cells are composed of cellulose, hemicellulose, and lignin. Geometrically we can idealize th... more Wood cells are composed of cellulose, hemicellulose, and lignin. Geometrically we can idealize them as a set of hollow cylinders touching each other on the cylinder surface. The continuous displacements and stress state transmission are assumed on the cylinder surfaces. The article investigates stress development which is influenced by the wood cell axial elongation. Material properties of individual constituents are generally described by nine parameters characterizing orthotropic elastic material. Transversely isotropic constitutive model of was chosen for simplification. The analytical solution of the stress state was driven by the ideas of displacement method. Material parameters have been estimated according to available literature. The main task of our investigation was focused on the effect of transversal contraction. The actual calculation results are surprising and lead to reflection. These considerations and conclusions are summarized at the end of the paper.
The Broumov group of churches represents an integral part of Bohemian baroque architecture. The f... more The Broumov group of churches represents an integral part of Bohemian baroque architecture. The famous Dientzenhofer family of architects, that helped define the Bohemian baroque style in the early 18th century, designed the Broumov group for the governing Benedictine abbey of St. Wenceslaw in Broumov. Variation of water table together with particular site conditions can cause mechanical damage with crack propagation and biological deterioration, as well. We prepared the project on advanced monitoring of stability and complex evaluation of the technical state of the structures proposing the expert remediation using comprehensive, complete elucidation and description of actual causes of degradation of bearing parts of the structure. Results of previous research connected with the Prague Castle monitoring are presented in the paper.
The Broumov group of churches represents an integral part of Bohemian baroque architecture. The f... more The Broumov group of churches represents an integral part of Bohemian baroque architecture. The famous Dientzenhofer family of architects, that helped define the Bohemian baroque style in the early 18th century, designed the Broumov group for the governing Benedictine abbey of St. Wenceslaw in Broumov. This report summarizes a structural investigation, using FIN10 finite element software, into the stability and efficiency of the roof trusses design. The structures age and current state were taken into account in calculating both the applied loads and structural capacity by increasing loads and reducing material strength. A damage analysis, including identification of fungi species, was performed, documented and implemented in a three-dimensional model for comparison with undamaged results. Magnitude and distribution of axial and bending forces were determined using both two dimensional and three-dimensional models for several load cases. Using the comparison of 1st order and 2nd ord...
This study was set to introduce a new intramedullary fixation, explore its biomechanical properti... more This study was set to introduce a new intramedullary fixation, explore its biomechanical properties, and provide guidance for further biomechanical experiments. With the help of CT scans and finite element modeling software, finite element model was established for a new intramedullary fixation and intramedullary nailing of femoral shaft fractures in a volunteer adult. By finite element analysis software ANSYS 10.0, we conducted 235-2,100 N axial load, 200-1,000 N bending loads and 2-15 Nm torsional loading, respectively, and analyzed maximum stress distribution, size, and displacement of the fracture fragments of the femur and intramedullary nail. During the loading process, the maximum stress of our new intramedullary fixation were within the normal range, and the displacement of the fracture fragments was less than 1 mm. Our new intramedullary fixation exhibited mechanical reliability and unique advantages of anti-rotation, which provides effective supports during fracture recovery.
This paper deals with Plaxis 3D finite element simulations of the mechanical response of deep fou... more This paper deals with Plaxis 3D finite element simulations of the mechanical response of deep foundations founded in a collapsible tropical soil. Main attention is initially paid to differences between single continuous flight auger (CFA) pile behavior and the behavior of CFA piles in standard groups. The numerically computed load-settlement curves are compared to field load test data obtained at the experimental research site of the University of Brasília (UnB), leading to conclusions about the appropriateness of adopting laboratory, in situ or back calculated parameters as input of numerical programs that simulate 3D foundation systems. Further, the contribution of the contact surficial soil/top raft is numerically examined by simulating the behavior of identical " piled raft " systems founded in the same site. The numerical simulated results of " piled raft " and standard pile group systems are then compared in terms of load capacity, system stiffness, load share between pile tip, shaft and raft, and mean developed lateral pile shaft friction. Having the results at distinct loading stages, as at working and failure levels, the analyses show the differential behavior, and design obtained responses, one may expect from conventional pile groups and " piled rafts " of CFA floating piles when founded in tropical soils. It is a mixed theoretical/experimental paper with practical interest for foundation designers and constructors.
The structural changes of interfacial transition zone of two concrete systems reinforced by polyp... more The structural changes of interfacial transition zone of two concrete systems reinforced by polypropylene/polyethylene and basalt fibers were studied by Raman microspectroscopy. The interfacial transition zone was found in the 0-20 µm in vicinity of quartz/feldspar aggregate surface. The calcium carbonate, ettringite and alite and belite bands were used for determination of interfacional transition zone size by Raman spectroscopy. Similar behaviour has been shown the cement matrix in neighbourhood of PP/PE fibers. There is not observed any concentration gradient of cement hydration product in the vicinity of 1 µm diameter basalt fiber.
The Churches of the Broumov region are well known for their unique baroque architecture, distinct... more The Churches of the Broumov region are well known for their unique baroque architecture, distinct shapes, sizes, and constitutes an integral part of the Czech cultural heritage. The St. Barbara’s Church that has been studied in this article, is in the Otovice village of Broumov. It was built in the year 1726 by Bavarian architects Christoph Dientzenhofer and Kilian Ignaz and is significant because of its religious, artistic and historic values. The main objective of this study is to evaluate the structural safety and stability of St. Barbara’s Church based on a probabilistic approach. A deterministic assessment of the structure is carried out and the results are assessed concerning the present site condition. Depending upon the observed damages, a condition for failure is defined for the structure. The uncertainties in the material parameters are considered and reliability analysis is performed to determine the reliability index, probability of failure and influence of different mat...
Proceedings of the 22nd Conference on the Rehabilitation and Reconstruction of Buildings
The churches of the Broumov region are renowned for their unique baroque architecture, their dist... more The churches of the Broumov region are renowned for their unique baroque architecture, their distinct shapes, and sizes. They are an integral part of the Czech cultural heritage. If you analyze the churches, it becomes evident that both the local geological conditions and the municipal economic situation have played an important role in their current condition. Moreover, the local construction industry has been significantly affected by historical events. In this article we would like to present the effects of those factors on the current state of selected churches, namely on the bearing capacity of their walls. Besides being very interesting, it also plays a key role in the maintenance and the potential reconstruction of the churches.
Broumov Region and its group of churches represent a perfect example of symbiosis between Baroque... more Broumov Region and its group of churches represent a perfect example of symbiosis between Baroque architecture and countryside landscape. This peculiar heritage site requires specialized analysis to preserve its uniqueness. St. Barbara Church in Otovice, the one investigated in this thesis, was built by Christoph and Kilian Dientzenhofer. Nowadays, concerns about its stability and degradation process led to the necessity to investigate more deeply its current condition. Therefore, the main objective of the article consists in the FEM modeling and the evaluation of the bearing capacity of enclosure walls, with particular attention on the influence of the soil deterioration. In conclusion, technical advices are recommended.
The paper shows numerical investigation of decay and damage appearing in the All Saints church, w... more The paper shows numerical investigation of decay and damage appearing in the All Saints church, which was selected from the Broumov group of churches. The study has been started off by summary of findings from preliminary historical, geotechnical background studies. Several conclusions of possible sources of decay and damage of the church were made. The most important sources include presence of moisture and possible differential soil settlement as a result of uneven deterioration of subsoil. In order to investigate the extent of damage series of FEM modeling was employed.
The known solution of isotropic elastic layer was modified for orthotropic elastic material behav... more The known solution of isotropic elastic layer was modified for orthotropic elastic material behavior in this contribution. The solution was original derived for calculation of footing settlement. However it should be useful for estimation of orthotropic material parameters. Timber is classical orthotropic material. Timber board which is placed on the rigid basement it could be considered as the elastic layer. From the known load displacement curve we can, vice versa, estimate the material parameters. The present solution should be able to control loading by rigid strip footing acting perpendicular to the plane of orthotropy. The contribution summarize the first steps of the proposed back analysis.
Wood cells are composed of cellulose, hemicellulose, and lignin. Geometrically we can idealize th... more Wood cells are composed of cellulose, hemicellulose, and lignin. Geometrically we can idealize them as a set of hollow cylinders touching each other on the cylinder surface. The continuous displacements and stress state transmission are assumed on the cylinder surfaces. The article investigates stress development which is influenced by the wood cell axial elongation. Material properties of individual constituents are generally described by nine parameters characterizing orthotropic elastic material. Transversely isotropic constitutive model of was chosen for simplification. The analytical solution of the stress state was driven by the ideas of displacement method. Material parameters have been estimated according to available literature. The main task of our investigation was focused on the effect of transversal contraction. The actual calculation results are surprising and lead to reflection. These considerations and conclusions are summarized at the end of the paper.
The Broumov group of churches represents an integral part of Bohemian baroque architecture. The f... more The Broumov group of churches represents an integral part of Bohemian baroque architecture. The famous Dientzenhofer family of architects, that helped define the Bohemian baroque style in the early 18th century, designed the Broumov group for the governing Benedictine abbey of St. Wenceslaw in Broumov. Variation of water table together with particular site conditions can cause mechanical damage with crack propagation and biological deterioration, as well. We prepared the project on advanced monitoring of stability and complex evaluation of the technical state of the structures proposing the expert remediation using comprehensive, complete elucidation and description of actual causes of degradation of bearing parts of the structure. Results of previous research connected with the Prague Castle monitoring are presented in the paper.
The Broumov group of churches represents an integral part of Bohemian baroque architecture. The f... more The Broumov group of churches represents an integral part of Bohemian baroque architecture. The famous Dientzenhofer family of architects, that helped define the Bohemian baroque style in the early 18th century, designed the Broumov group for the governing Benedictine abbey of St. Wenceslaw in Broumov. This report summarizes a structural investigation, using FIN10 finite element software, into the stability and efficiency of the roof trusses design. The structures age and current state were taken into account in calculating both the applied loads and structural capacity by increasing loads and reducing material strength. A damage analysis, including identification of fungi species, was performed, documented and implemented in a three-dimensional model for comparison with undamaged results. Magnitude and distribution of axial and bending forces were determined using both two dimensional and three-dimensional models for several load cases. Using the comparison of 1st order and 2nd ord...
This study was set to introduce a new intramedullary fixation, explore its biomechanical properti... more This study was set to introduce a new intramedullary fixation, explore its biomechanical properties, and provide guidance for further biomechanical experiments. With the help of CT scans and finite element modeling software, finite element model was established for a new intramedullary fixation and intramedullary nailing of femoral shaft fractures in a volunteer adult. By finite element analysis software ANSYS 10.0, we conducted 235-2,100 N axial load, 200-1,000 N bending loads and 2-15 Nm torsional loading, respectively, and analyzed maximum stress distribution, size, and displacement of the fracture fragments of the femur and intramedullary nail. During the loading process, the maximum stress of our new intramedullary fixation were within the normal range, and the displacement of the fracture fragments was less than 1 mm. Our new intramedullary fixation exhibited mechanical reliability and unique advantages of anti-rotation, which provides effective supports during fracture recovery.
This paper deals with Plaxis 3D finite element simulations of the mechanical response of deep fou... more This paper deals with Plaxis 3D finite element simulations of the mechanical response of deep foundations founded in a collapsible tropical soil. Main attention is initially paid to differences between single continuous flight auger (CFA) pile behavior and the behavior of CFA piles in standard groups. The numerically computed load-settlement curves are compared to field load test data obtained at the experimental research site of the University of Brasília (UnB), leading to conclusions about the appropriateness of adopting laboratory, in situ or back calculated parameters as input of numerical programs that simulate 3D foundation systems. Further, the contribution of the contact surficial soil/top raft is numerically examined by simulating the behavior of identical " piled raft " systems founded in the same site. The numerical simulated results of " piled raft " and standard pile group systems are then compared in terms of load capacity, system stiffness, load share between pile tip, shaft and raft, and mean developed lateral pile shaft friction. Having the results at distinct loading stages, as at working and failure levels, the analyses show the differential behavior, and design obtained responses, one may expect from conventional pile groups and " piled rafts " of CFA floating piles when founded in tropical soils. It is a mixed theoretical/experimental paper with practical interest for foundation designers and constructors.
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Papers by Pavel Kuklík