PRINCIPLES OF RELIABILITY EVALUATION OF REINFORCED CONCRETE BEAMS, STRENGTHENED WITH ADDITIONAL REINFORCING BARS UNDER LOADING

Visnyk LNAU: Architecture and Farm Building 2018 №19: 94-97

PRINCIPLES OF RELIABILITY EVALUATION OF REINFORCED CONCRETE BEAMS, STRENGTHENED WITH ADDITIONAL REINFORCING BARS UNDER LOADING

Tytarenko R.Yu., postgraduate student
Khmil R.Ye., PhD, Assosiate Professor
Lviv Polytechnic National University

https://doi.org/10.31734/architecture2018.19.094

Annotation

The article highlights advantages of probabilistic methods of calculation of building constructions, including the possibility of establishing a guaranteed level of reliability of construction at the design stage, as well as calculating the quantitative assessment of its reliability, using the probabilistic indicators.

Taking into account a growth of reconstruction’s works of existing buildings and structures, the theoretical model of calculation of reliability of reinforced concrete (RC) beams (like the bending members, that often require strengthening during reconstruction), strengthened with additional reinforcing bars under loading is proposed.

The technical literature on the topic of theoretical research (manuals, recommendations, publications, dissertations, etc.) is also analyzed. On the basis of this analysis, the questions, which are sufficiently studied as of today, as well as actual objectives and problems, that require further development, theoretical and experimental investigations are highlighted; including the such problem as taking into account the level of loading on strengthening RC bending members when we evaluate their reliability.

On the basis of the adaptation of the existing methodology of reliability design and also using the fundamental thesis of probability theory, the principle analytical method for assessing of reliability of RC beams, strengthened with additional reinforcing bars under load is developed. It allows include in the reliability design the following stochastic parameters: the strength of concrete, as well as stretched and compressed reinforcement (variability of strength parameters); the level of loading at which is performed strengthening additional reinforcing bars (variability of load parameter); width and resulted working height of the cross section after strengthening (variability of geometric parameters).

Key words

reliability evaluation, probability of failure, stochasticity, strengthening, load level, reinforced concrete beam, additional reinforcement, methodology

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