APPLICATION OF NON-REMOVABLE TUBULAR COLLECTORS AND LIGHT-WEIGHT CONCRETE FOR REDUCING THE WEIGHT OF REINFORCED CONCRETE STRUCTURES AS ONE OF THE WAYS TO REDUCE THE SEISMIC IMPACT ON HIGH-RISE BUILDINGS

Abstract

Annotation. The article gives examples of buildings and structures, successfully and unsuccessfully designed and built, shows their characteristic features, analyzes publications that justify the need to reduce the weight of structures; reducing the location of the center of gravity of the masses, the use of constructive solutions of the building itself capable of counteracting seismic effects. An example of the design and calculation of two design options for a twelve-story residential building of various weights using heavy and lightweight concrete and non-removable cardboard-polyethylene void formers with a circular cross section with a diameter of 159 mm is given as one of the methods aimed at reducing seismic impact. Based on the studies performed, it was concluded that it is expedient to use non-removable void formers in combination with lightweight concrete to reduce the mass of reinforced concrete structures and heavy concrete to reduce the center of gravity of the building, and as a result, reduce the seismic impact.

Subject of study. The subject of the study is to reduce the mass of reinforced concrete structures of high-rise buildings and their center of gravity, as well as the construction of the building itself in seismic zones.

Materials and methods. To reduce the mass of reinforced concrete structures, the frame was designed and the center of gravity of a twelve-story residential building was calculated in two options - the first option: the use of heavy reinforced concrete completely 2.5 t/m3 and solid floor slabs 22 cm thick; the second option is the use of heavy reinforced concrete with a density of 2.5 t/m3 to cover the basement and the lower four floors, the rest of the upper floors using light reinforced concrete with a density of 1.7 t/m3 and non-removable cardboard-polyethylene void formers with a diameter of 159 mm for floor slabs. The possibility, expediency and application of building design according to the second option are substantiated.

Results.

1) Reducing the center of gravity of the building by 16.3%.

2) Reducing the mass of the building while maintaining the standard loads: 20.5%.

3) The cumulative reduction in the mass of reinforced concrete elements is 30.7%.

Conclusions. The proposed design of a monolithic twelve-story residential building using heavy concrete on the lower floors and lightweight concrete in combination with non-removable cardboard-polyethylene tubular hollow formers of circular cross section with a diameter of 159 mm on the upper floors, providing a significant reduction in the mass and center of gravity of the building, is a possible and expedient way to build in seismically dangerous regions.