Estimation of Pre-Stress Losses in the Reinforcement Due to the Creep of Autoclaved Aerated Concrete

One of the ways to increase the durability of the external wall panels of cellular concrete is the use of pre-stressed reinforcement, which can significantly increase their stiffness and crack resistance. The article presents the results of experimental studies of tension losses in the reinforcement due to the creep of concrete for pre-stressed aerated concrete elements. It is established that these losses linearly depend on the initial level of compression in aerated concrete in the range from 0.3 to 0.6 of its prismatic strength and constitute 22–30%. Residual stresses in the stressed reinforcement range from 136 to 245 MPa, which is sufficient to ensure the operational crack resistance of large-size products of aerated concrete during moisture exchange and carbonizing processes. The obtained results are the basis for further development of the method for calculating stress losses in the reinforcement due to the aerated concrete creep, as well as when preparing recommendations for the design and manufacture of pre-stressed enclosing structures of cellular concrete.

M.A. GAZIEV, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.)

Grozny State Oil Technical University named after Academician M.D. Millionshchikov (100, Kh.A. Isaeva Avenue, Grozny, Chechen Republic, 364061, Russian Federation)

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