|
| |
|
|
Reconstruction and strengthening of reinforced concrete ceiling construction
Klimeš, Petr ; Zich, Miloš (referee) ; Perla, Jan (advisor)
The final thesis deals with strengthening of cast-in-place concrete ceiling in existing construction for couple of escalators. New prestressed beam, columns in new positions and strengthened girder with unbonded strands are building in this adjustments. Every member, including the existing construction, is verified for ultimate and serviceability limit state. Prestressed members are alternatively designed with bonded strands and these variants are comparison in terms of utilization and calculation.
|
|
| |
|
|
Experimental and numerical analysis of strengthened reinforced concrete member with rigid boundary conditions
Ptáčková, Kristina ; Láník, Jaromír (referee) ; Žítt, Petr (advisor)
A proposal how to conduct a compression test of reinforced concrete objects with one beam inserted from both sides exposed to a four-point bending. A theoretical proposal of the most appropriate form of reinforcement of the reinforced concrete object including a suggestion how to increase its tensile strength based on the chosen crushing load and the positioning of the beam (static calculation). Presentation of the project, static compression test measurement and all the other necessary measurements (elastic modulus, strenth of the material etc.). Development of a mathematical model with the help of Atena software. Evaluation and comparison of the results in analytical and experimental part of the project. Recommendations for implementation of similar experimental tests.
|
|
|
Structural laminated wood reinforced with composite materials
Kovács, Pavel ; Horák, David (referee) ; Žítt, Petr (advisor)
This master’s thesis describes an experimental program investigating the strengthening of beams of glued laminated timber with composite reinforcement. The work compares the behavior of beams reinforced with composite reinforcement with unreinforced beam and with solid timber beam. The work also deals with identifying and evaluating the physic-mechanical properties of materials.
|
|
| |
|
|
Strengthening of reinforced concrete frame structure
Jelínek, Tomáš ; Laníková, Ivana (referee) ; Šimůnek, Petr (advisor)
This thesis reviews a strengthening of reinforced concrete column in frame structure. The column is strengthened with angles and battens. This work is divided into three parts. In the first part there is chosen an appropriate theoretical model. In the second part there is described every step of the design and the assessment which is based on two assumptions. Angles are expected to carry a part of load directly. Concrete is confined with battens. Therefore we can expect better deformation characteristics. There was also used a program ATENA 3D to elucidate one of the problems. The third part consists of designing and assessment of a particular column.
|
|
| |
|
|
Strengtheninig of whitish degraded porous limestone by suspension of nanoparticles of calcium hydroxide in alcohol
Slížková, Zuzana ; Frankeová, Dita
Limestone, which is damaged (degraded) in its surface layer, and having a suitable pore size, ie. that contain cracks or pores with a diameter greater than one micron, it is possible to consolidate by calcium hydroxide in the form of particles of a size of hundreds of nanometers. Suspension (also called dispersion, a colloidal sol) of nano-particles of calcium hydroxide in ethanol, may have different concentrations and can be applied to damaged limestone one or more times in various amounts, depending on its concentration and properties of the stone. The procedure specifies the limestone material tests carried out before the intervention and the possibility of minimizing whitish haze on the surface of the treated stone.
Fulltext: content.csg -  PDF
Plný tet: 0448865_2015_Slizkova_Frankeova_Zpevneni_belaveho_degradovaneho_porezniho_vapence_suspenzi_nanocastic_hydroxidu_vapenateho_v_alkoholu_PP_4 - PDF
|
|
|
Strengthening of weak historic renders with traditional and innovated consolidation treatment
Slížková, Zuzana ; Frankeová, Dita
The presented study was aimed to proof consolidation effects of different families of consolidants: inorganic agents (lime -based or silica-based solutions or sols), organic agents (silicic acid ester based consolidant) and their combination on the characteristics of weak mortars prepared in laboratory with different types of aggregates. Besides exploring consolidant-substrate interaction also the pozzolanic activity of the aggregate and the binder mortar component after reaction with lime (calcium hydroxide solution) was investigated in order to understand and describe the strengthening mechanism into consolidated mortars. As the study was based on experimental research, the production of mortar test specimens represented an important preliminary work. Different mortar components (various types of sand in terms of phase composition, clay, lime) and the same ratio of the aggregate and the binder were used in various mortar mixtures. Various mineralogical types of aggregate were used with the same grain size distribution (600 pieces of tubes of 40 mm in outer diameter, of the height of 40 mm and depth of 4 mm were prepared for testing the compressive strength, for the tension tests 550 thin plates of dimensions 40 mm x 100 mm x 4 mm were cast and 600 beams 20 x 20 x100mm were made for testing the flexural strength and other characteristics of reference and consolidated mortars). The sand used for mortar specimens was characterized by microscopic examination of thin section and also by X-ray diffraction, X-ray fluorescence spectroscopy and thermal analysis. The pozzolanic activity of the sands (reactivity with calcium hydroxide) was determined by means of the thermal analysis and supplemented by wet silicate analysis. The amount of the effective matter in the consolidant was the same for all agents per the square unit for all mortar types and specimen shape. One set of specimens was prepared as the reference set the second set was used for the evaluation.
Fulltext: content.csg - PDF
Plný tet: 0443951_2015_Slizkova_Frankeova_Strengthening_of_weak_historic_renders_with_traditional_and_innovated_consolidation_treatment - PDF
|
guest ::
