|
|
Strengthening of vaulted structures by prestressing
Požár, Michal ; Solař,, Jaroslav (referee) ; Drahorád,, Michal (referee) ; Klusáček, Ladislav (advisor)
The topic of this Ph.D. theis is repairing and strengthening of historical wagon vaults (barrel vaults, tunnel vaults) using post tensioning with tendons (monostrands) in longitudinal direction. The vaults should be without an edge, that´s mean the baroque vaults are well appropriate for this method. The pointed barrel vault should be problematic. The stabilization is for a wagon vault created by semicircle or segment part of a circle as well as an elliptic shape. The study has been made for vault with a width of 1 m and for the prestressing force has been used one tendon only. Of course, this method could be apply for normal constructions with a width of many meters. In this case, more tendons should be use with a suitable spacing. The goal of this work was to monitor an experiment model of an wagon vault and a real strengthened baroque vault of a church in Švábenice. During the monitor time, the static Analysis has been made. For these analysis appropriate finite elements in Ansys program has been use. The results of this work is to amplify the knowledge of the real behaviour of strengthened vaults, which could be use like instruction for the civil engineers. Further the public information guide to build an appropriate model of an Vault with an interaction with post-tensioning tendons.
|
|
|
Plan curved cable stayed pedestrian bridge
Müller, Radek ; Kaláb,, Pavel (referee) ; Koláček, Jan (advisor)
In my thesis, I created a study of plan curved cable stayed pedestrian bridge. As the main construction material is used prestressed concrete. Suspenders and railing are made from steel. The footbridge has a length of 130,00 meters and a width of 3,70 meters. The plan shape of the structure is composed of two oposite arches. Bridge deck is made of box girder. The bridge deck is single-side suspended on two concrete pylons with a height of 39,00 m. Pylons are supported by suspender.
|
|
|
Static securing of church
Jelínek, Lukáš ; Šiška, Radek (referee) ; Strnad, Jiří (advisor)
This thesis addresses the static security chapel in Medlice. The chapel is a single-Gothic style. The other two dimensions 8x14 m chapels are part of the chapel tower is 20 m high with dimensions of 2,6 x2, 6 m Chapel was built in 1901. The truss chapel was damaged by pests, and therefore, a need to examine and exchange truss. On this occasion, establish a reinforced concrete ring that object until now lacked. In bearing walls of the chapel are visible cracks and occurs because the horizontal bracing object using a technology called monostrands.
|
|
|
Bridge on a ramp in Brno
Diviš, Dalibor ; Pachl, Radek (referee) ; Panáček, Josef (advisor)
Thesis involves designing and analysis of horizontally curved bridge contruction with chamber-shaped profile and oblique side walls. The object is a part of fly-over crossig at VMO Brno. Calculations are according to actually valid standards ( Eurocodes ). Thesis gives a basic look at the problematics of horizontaly curved bridge construction, including solution of prestressing cables´ 3D-tracking with usage of common software.
|
|
|
Strengthening of vaulted structures by prestressing
Požár, Michal ; Solař,, Jaroslav (referee) ; Drahorád,, Michal (referee) ; Klusáček, Ladislav (advisor)
The topic of this Ph.D. theis is repairing and strengthening of historical wagon vaults (barrel vaults, tunnel vaults) using post tensioning with tendons (monostrands) in longitudinal direction. The vaults should be without an edge, that´s mean the baroque vaults are well appropriate for this method. The pointed barrel vault should be problematic. The stabilization is for a wagon vault created by semicircle or segment part of a circle as well as an elliptic shape. The study has been made for vault with a width of 1 m and for the prestressing force has been used one tendon only. Of course, this method could be apply for normal constructions with a width of many meters. In this case, more tendons should be use with a suitable spacing. The goal of this work was to monitor an experiment model of an wagon vault and a real strengthened baroque vault of a church in Švábenice. During the monitor time, the static Analysis has been made. For these analysis appropriate finite elements in Ansys program has been use. The results of this work is to amplify the knowledge of the real behaviour of strengthened vaults, which could be use like instruction for the civil engineers. Further the public information guide to build an appropriate model of an Vault with an interaction with post-tensioning tendons.
|
|
|
Plan curved cable stayed pedestrian bridge
Müller, Radek ; Kaláb,, Pavel (referee) ; Koláček, Jan (advisor)
In my thesis, I created a study of plan curved cable stayed pedestrian bridge. As the main construction material is used prestressed concrete. Suspenders and railing are made from steel. The footbridge has a length of 130,00 meters and a width of 3,70 meters. The plan shape of the structure is composed of two oposite arches. Bridge deck is made of box girder. The bridge deck is single-side suspended on two concrete pylons with a height of 39,00 m. Pylons are supported by suspender.
|
|
|
Kotvení předpjaté frp výztuže pro betonové konstrukce
Girgle, František ; Horák, David ; Štěpánek, Petr ; Laníková, Ivana ; Šimůnek, Petr
Non-metallic reinforcement has many advantages, but there are some areas of application that need to be resolved to improve the usage of FRP reinforcement in real conditions. One of the disadvantages of FRP reinforcement is its lower modulus of elasticity, which leads to greater deflections of structures and can also cause early propagation of cracks. The paper deals with the possibility of eliminating this problem by prestressing the reinforcement. It covers several problems related to anchoring and current anchoring methods used world-wide. The paper also mentions some drawbacks of these methods. In an effort to bypass these drawbacks a new anchoring method has been developed. It differs in the way longitudinal forces are transferred from the bar to the surrounding concrete. Basically, it is based on the addition of an additional anchoring member (cylinder) on the surface. This member is made of polymers so the whole system remains completely steel-free and very simple to produce. Before using the system in real structures a series of tests were performed and the results are presented. Also, some prestressed test panels were prepared and compared with standard panels.
|
|
|
Static securing of church
Jelínek, Lukáš ; Šiška, Radek (referee) ; Strnad, Jiří (advisor)
This thesis addresses the static security chapel in Medlice. The chapel is a single-Gothic style. The other two dimensions 8x14 m chapels are part of the chapel tower is 20 m high with dimensions of 2,6 x2, 6 m Chapel was built in 1901. The truss chapel was damaged by pests, and therefore, a need to examine and exchange truss. On this occasion, establish a reinforced concrete ring that object until now lacked. In bearing walls of the chapel are visible cracks and occurs because the horizontal bracing object using a technology called monostrands.
|
|
|
Bridge on a ramp in Brno
Diviš, Dalibor ; Pachl, Radek (referee) ; Panáček, Josef (advisor)
Thesis involves designing and analysis of horizontally curved bridge contruction with chamber-shaped profile and oblique side walls. The object is a part of fly-over crossig at VMO Brno. Calculations are according to actually valid standards ( Eurocodes ). Thesis gives a basic look at the problematics of horizontaly curved bridge construction, including solution of prestressing cables´ 3D-tracking with usage of common software.
|
guest ::
