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NVH parameter determinantion of plate
Bouchner, Michal ; Prokop, Aleš (referee) ; Řehák, Kamil (advisor)
The aim of this thesis is examination and verification of numeric model for solving acoustics and vibration problems. Specifically, we are speaking about cast iron plate machined from gearbox. Main objectives of this work is set of experimental and numerical analysis at this simplified part with follow-up numerical model, where same analyses examining not only structure, but especially acoustic space around were performed. Due to this we were able to compare data between experimental and numerical analyses and to be able to prove or disprove functionality and limitation of numerical model.
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Possibilities of dispersed reinforcement for lightweight concrete
Novotná, Aneta ; Žítt, Petr (referee) ; Láník, Jaromír (advisor)
Master´s thesis deals with some problems associated with utilisation of lightweight concrete from the porous aggregates in the load – carrying structures. The thesis focuses on the possibilities of the increase of the cement composites toughness using dispersed reinforcement. Lightweight concretes were reinforced with a combination of different lengths of polypropylene fibers Forta Ferro. There were used polypropylene fibers of three lengths 19, 38, 54 mm. The thesis is divided into theoretical, experimental and static part.
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Steel-Concrete Columns Composed of High-Strength Materials
Röder, Václav ; Štěpánek, Petr (referee) ; Studnička,, Jiří (referee) ; Vičan,, Josef (referee) ; Karmazínová, Marcela (advisor)
The main objective of this thesis is the verification of the buckling strength of the composite compression members which were made from high-strength materials. This thesis is divided into four main chapters which are interconnected. The first chapter summarizes the current state of the problem of the compression members. The basis of this part is the elementary theories and researches, the task of this text is attempted to understand and obtain normative procedures which are important for practical use. The second part deals with the theoretical analysis of composite column, mainly with the examination of the individual effects on the buckling strength. The result of the first and the second parts is analytical algebraic equations which determine the buckling strength of the member. The third part contains the numerical analysis, which leads to create a numerical model of the compression column. The numerical model is used for the verification of the theoretical analysis and for the investigation of the behaviour of the column loaded by axial force. The last part deals with the experimental verification of the previous analyses. There are tested various types of the composite columns, which were made of steel with a yield strength up to 455 MPa and of the concrete with a cube compression strength up to 102 MPa. Experimental results confirmed the high reliability of centrally loaded column and every tested columns failed by flexural buckling. The final step is evaluation and comparison of the results obtained from previous four parts. It was founded that design criteria for centrally loaded steel-concrete column are too conservative and design relationships doesn´t use the positive properties of high-strength materials for economic design.
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Experimental and Numerical Analysis of the Volume Changes of Fine-grained Concretes
Odstrčil, Štěpán ; Frantík, Petr (referee) ; Kucharczyková, Barbara (advisor)
This diploma thesis deals with the experimental and numerical analysis of volume changes of fine-grained concrete. Experiments were carried out, measuring both the length changes as well as the mass losses and the internal temperature of the test specimens made from fine-grained concrete. The measurements were divided into two parts (phases). The first phase took approx. 72 hours. The second phase was focused on the long-term measurements and will be completed after stabilization of the mass losses and length changes. In the diploma thesis, the first phase of measurement was elaborated in detail, both in terms of experimental and numerical analysis. In addition, a C # .NET program was created to facilitate the processing of raw measurement data from the data logger. Finally, a comparative calculation was performed according to the model B4, where the result of the calculation was compared with the results of the experiment.
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Stability problems of laminated structural glass members
Pešek, Ondřej ; Lokaj,, Antonín (referee) ; Brodniansky,, Ján (referee) ; Melcher, Jindřich (advisor)
Transparent and subtle structures are features of modern architecture. Structural glass is constructional material that provides to realize architect's visions and ideas. Glass as a constructional material is more often used as a material for primary load-bearing structures. Realization of safe, reliable and economic glass structure is real challenge for structural engineers because of absence of standards for designing of glass members and elements. Compressed members (columns), bended members (beams) and members loaded by compression and bending (beam-columns) were analysed in the frame of the doctoral thesis whereby the emphasis is being placed on the lack of stability – flexural buckling, lateral-torsional buckling and flexural-lateral-torsional buckling. Measuring of shape and amplitude of initial geometrical imperfections is a part of doctoral thesis. The theoretical analysis describes the behaviour of the member by means of solving the differential equations. The solution according to the second order theory developed for metal members is applied on structural laminated glass members with use of effective cross-sectional characteristics. Numerical analysis is focused on the use of commonly available software based on finite element method in order to predict the load-bearing resistance of laminated glass members. Actual behaviour of laminated and monolithic structural glass members was found within experimental program. The correctness of FEM model and analytical solutions were evaluated by comparing with test results. The goal of the doctoral thesis was determine of buckling curves for calculation of flexural buckling and lateral-torsional buckling resistances by the same calculation procedure as for metal members. Because of small number of experimentally tested specimens the Monte Carlo simulation was performed.
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Analysis of a joint of steel tubes members and its practical use in load-bearing structure of a pedestrian bridge
Kuttelwascherová, Olga ; Balázs, Ivan (referee) ; Pešek, Ondřej (advisor)
This master‘s thesis deals with the analysis of the behaviour of the joint and its subsequent use in the supporting steel structure of the pedestrian bridge. The detail in question may find application as a structural solution for the crossing of closed cross-sections. The analysis of the joint consists of experimental analysis, numerical analysis and parametric study. Furthermore, the structural design of the pedestrian bridge was carried out. The pedestrian bridge is located in the grounds of a primary school in Litomyšl. It enables the connection of two existing buildings. In the design of the pedestrian bridge, the detail in question is used at the crossing point of the bracings. All steel elements are designed in S355 structural steel. In addition, wooden elements for the walking surface are designed in C30 coniferous wood and glass panes acting as a curtain made of insulating glass. Dlubal RFEM was chosen for the numerical analysis, parametric study and the structural model of the pedestrian bridge.
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Stability problems of laminated structural glass members
Pešek, Ondřej ; Lokaj,, Antonín (referee) ; Brodniansky,, Ján (referee) ; Melcher, Jindřich (advisor)
Transparent and subtle structures are features of modern architecture. Structural glass is constructional material that provides to realize architect's visions and ideas. Glass as a constructional material is more often used as a material for primary load-bearing structures. Realization of safe, reliable and economic glass structure is real challenge for structural engineers because of absence of standards for designing of glass members and elements. Compressed members (columns), bended members (beams) and members loaded by compression and bending (beam-columns) were analysed in the frame of the doctoral thesis whereby the emphasis is being placed on the lack of stability – flexural buckling, lateral-torsional buckling and flexural-lateral-torsional buckling. Measuring of shape and amplitude of initial geometrical imperfections is a part of doctoral thesis. The theoretical analysis describes the behaviour of the member by means of solving the differential equations. The solution according to the second order theory developed for metal members is applied on structural laminated glass members with use of effective cross-sectional characteristics. Numerical analysis is focused on the use of commonly available software based on finite element method in order to predict the load-bearing resistance of laminated glass members. Actual behaviour of laminated and monolithic structural glass members was found within experimental program. The correctness of FEM model and analytical solutions were evaluated by comparing with test results. The goal of the doctoral thesis was determine of buckling curves for calculation of flexural buckling and lateral-torsional buckling resistances by the same calculation procedure as for metal members. Because of small number of experimentally tested specimens the Monte Carlo simulation was performed.
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NVH parameter determinantion of plate
Bouchner, Michal ; Prokop, Aleš (referee) ; Řehák, Kamil (advisor)
The aim of this thesis is examination and verification of numeric model for solving acoustics and vibration problems. Specifically, we are speaking about cast iron plate machined from gearbox. Main objectives of this work is set of experimental and numerical analysis at this simplified part with follow-up numerical model, where same analyses examining not only structure, but especially acoustic space around were performed. Due to this we were able to compare data between experimental and numerical analyses and to be able to prove or disprove functionality and limitation of numerical model.
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|
|
Experimental and Numerical Analysis of the Volume Changes of Fine-grained Concretes
Odstrčil, Štěpán ; Frantík, Petr (referee) ; Kucharczyková, Barbara (advisor)
This diploma thesis deals with the experimental and numerical analysis of volume changes of fine-grained concrete. Experiments were carried out, measuring both the length changes as well as the mass losses and the internal temperature of the test specimens made from fine-grained concrete. The measurements were divided into two parts (phases). The first phase took approx. 72 hours. The second phase was focused on the long-term measurements and will be completed after stabilization of the mass losses and length changes. In the diploma thesis, the first phase of measurement was elaborated in detail, both in terms of experimental and numerical analysis. In addition, a C # .NET program was created to facilitate the processing of raw measurement data from the data logger. Finally, a comparative calculation was performed according to the model B4, where the result of the calculation was compared with the results of the experiment.
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Steel-Concrete Columns Composed of High-Strength Materials
Röder, Václav ; Štěpánek, Petr (referee) ; Studnička,, Jiří (referee) ; Vičan,, Josef (referee) ; Karmazínová, Marcela (advisor)
The main objective of this thesis is the verification of the buckling strength of the composite compression members which were made from high-strength materials. This thesis is divided into four main chapters which are interconnected. The first chapter summarizes the current state of the problem of the compression members. The basis of this part is the elementary theories and researches, the task of this text is attempted to understand and obtain normative procedures which are important for practical use. The second part deals with the theoretical analysis of composite column, mainly with the examination of the individual effects on the buckling strength. The result of the first and the second parts is analytical algebraic equations which determine the buckling strength of the member. The third part contains the numerical analysis, which leads to create a numerical model of the compression column. The numerical model is used for the verification of the theoretical analysis and for the investigation of the behaviour of the column loaded by axial force. The last part deals with the experimental verification of the previous analyses. There are tested various types of the composite columns, which were made of steel with a yield strength up to 455 MPa and of the concrete with a cube compression strength up to 102 MPa. Experimental results confirmed the high reliability of centrally loaded column and every tested columns failed by flexural buckling. The final step is evaluation and comparison of the results obtained from previous four parts. It was founded that design criteria for centrally loaded steel-concrete column are too conservative and design relationships doesn´t use the positive properties of high-strength materials for economic design.
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