ANALYSIS OF THE DAMAGES OF REINFORCED CONCRETE FRAMES OF HOTEL «DNISTER» IN LVIV

Visnyk LNAU: Architecture and Farm Building 2020 №21: 27-33

ANALYSIS OF THE DAMAGES OF REINFORCED CONCRETE FRAMES OF HOTEL «DNISTER» IN LVIV

Vikhot S., Candidate of Engineering Science
National University "Lviv Polytechnic"
Vybranets Yu., Candidate of Engineering Science
National University "Lviv Polytechnic".
Burchenya S., Candidate of Engineering Science
Lviv National Agrarian University

https://doi.org/10.31734/architecture2020.21.027

Annotation

In 1975, during the construction of the Dniester Hotel in Lviv (at the unfinished stage of construction), cracks were found in the beams, under partial operational load.

The analysis of the technical inspection results showed that all spans of the beams had oblique cracks in the zones of maximum transverse force, and the width of these cracks (up to 1,0 mm) significantly exceeded the allowable figure according to current design standards for operation. It caused emergency state and the need to strengthen the structures.

For safe operation, a variant of reinforcement of reinforced concrete frames MS-1 of the hotel building has been developed.

Reinforcements, which were provided for expansion of the column at the level of the first floor and the installation of puffs within the consoles at the level of the third floor, did not ensure reliable operation of the beam. This is evidenced by gypsum beacons, applied on cracks in the beams in 1975 and 2006, which revealed cracks. The cracking analysis showed that in all spans of beams had oblique cracks in the zones of maximum transverse force, and the width of these cracks (up to 1.3 mm) significantly exceeded (4 times!) the allowable figure according to current design standards for the stage operation.

The re-inspection of the frame structures (2015) revealed significant deviations from the design at the joints of the prefabricated columns and therefore the project provided for a comprehensive reinforcement of columns and beams. Unfortunately, that reinforcement does not perform the tasks in the proper way. Therefore, it is necessary to make additional reinforcement of the reinforced concrete beams with struts from the cantilever sections with direct concreting of steal clamps.

The performed reinforcement will ensure the appropriate further operation of the beam and the building as a whole. The purpose of reinforcement is to install additional supports that do not change the existing design scheme of the reinforced concrete beams. When the reinforcement elements are included in full operation, the reference bending moments are reduced. In addition, the arranged bars and wrapped with carbon composite secure the load-bearing capacity of the structure.

Key words

beam reinforcement, reinforced concrete, technical inspection, reinforcement, bearing capacity.

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