REPAIR AND STRENGTHENING OF FLOORS ON METAL BEAMS

Abstract

Methods of repair and strengthening of floors on metal beams are investigated. Operational requirements for floors are considered. The main causes of defects are analyzed. The analysis and advantages and disadvantages of methods of repair and strengthening of floors on metal beams are carried out. As a result of comparison of methods the conclusion is made.Attic and mezzanine floors are an important and significant structural element of buildings and structures. Their maintenance and repair work requires significant costs. The share of repair work is 14...33 %. Floors in buildings of different years have a great variety of design solutions. They have different beams between the capital walls and are usually made of materials that are different in durability. The experience of operation of buildings and structures made it possible to identify the most characteristic defects and damages in the structures of floors. These include: excessive deflections of wooden and metal beams and, as a consequence, the "fragility" of structures, as well as cracks in the surface of the ceiling; damage to brick and concrete vaults; the appearance of moisture on the ceilings in the area of adhesion of metal beams to the outer walls; deterioration of sound and heat-insulating characteristics for interfloor and attic (basement) overlappings accordingly; increase of moisture and gas permeability in damp and technological rooms.The main reasons for the appearance of the above defects are: the influence of external factors (freezing, increased loads, leaks due to accidents in sanitary systems, etc.); influence of technological processes; errors during design and violation of the process of work, the use of poor quality materials, non-compliance with the rules of operation. During the repair of floors on metal beams, the following types of work are performed: complete replacement of floors, replacement of wooden filling with reinforced concrete with simultaneous reinforcement of load-bearing metal beams, repair or reinforcement of concrete (brick) vaults.During replacement of overlappings on metal beams the technological process contains the following operations: installation and fixing of a scaffolding; additional strengthening of bearing elements; transportation of details of designs and materials; strengthening and relocation of existing sections of walls; strengthening of non-demountable floor structures; arrangement of nests in the walls under the metal beams; installation of beams with installation of struts from wooden bars for ensuring rigidity in the horizontal plane; self-counting of the ends of metal beams in nests and the device of filling from flat reinforced concrete plates.