Кауров А. И.

STRENGTH OF SLOPING SECTION OF PRESTRESSED FLEXURAL ELEMENTS WITH HIGH-STRENGTH AT- 1200 CLASS STEEL REINFORCE

The article presents the trial results of the thermo-mechanical reinforced
30HGS2(30ХГС2)grade Аt-1200steel, one of the best high-strength Russian reinforced steels,
on the basis of the first time ever rolled assortment test lots (10 ... 32 mm).
This article gives a generalized assessment of physical, mechanical and service properties
for the given grade of reinforced steel in as-delivered condition and after prestressing.
It reflects the research data of Аt-1200 reinforced steel prestressing influence on strength
and deformation properties. An analytical dependence for the initial and "reinforced" diagrams
approximation of deformed steel is offered.
The following methods are developed according to the results of experimental and theoretical studies of the trial flexural members with Аt-1200 reinforced steel during preoperational
stage of reinforcement tension release, under load and at simulation of load phase. The first one
is a calculation method of the longitudinal crack resistance of the end sections’ beam elements
at reinforcement tension release. And another one is a calculation method of the standard crosssections using real rebar load-elongation diagram, method of calculating the strength of sloping
sections.
It is proved that standard cross-sections’ strength of prestressed flexural elements increases due to identified strengthening effect of the reinforced steel.
The possibility of rational use of innovative steel class At1200 as a strained fixture of
curved elements is justified.

Keywords: load-bearing capacity, load-elongation diagram, prestressing, reinforced concrete structures, Reinforced steel, the strength of normal and sloping sections., Арматурная сталь, диаграмма растяжения, железобетонные конструкции, нормальные и наклонные сечения., предварительное напряжение