5.3 EVALUATION OF THE INFLUENCE OF CHEMICAL ADDITIVES ON THE STRENGTH OF CONCRETE HARDENED UNDER DIFFERENT CONDITIONS

Abstract

This article discusses the use of accelerated hardening concrete with the use of chemical additives using the example of the production of hollow-core floor slabs with dimensions of 4.2 ´x 3.0 m, series 1.090.1-1/88.

Key words: accelerated hardening concrete, chemical additive, hardening accelerator, strength.

These floor slabs, 4180 mm long and 2980 mm wide, were developed by SP Binokor Temir Beton Servis (Tashkent) in 2005 for use in the design and construction of multi-story residential buildings, public and industrial buildings. The prerequisites for the development of these floor slabs were: ‒ effective use of "wide" slabs in order to reduce the number of crane lifts during the installation of buildings, ‒ reduction of slab joints falling on the ceiling surface of living rooms, ‒ feasibility of placing stacks of slabs on storage areas with reduced passages between stacks. Slabs of this series are produced without pre-stressing, due to which the technology for the production of hollow-core slabs allows us to consider the possibility of their manufacture without the use of heat treatment, i.e., on natural hardening.