Method of construction of the beams in concrete weapon has increased resistance to fire, and the beam in the weapon according to this concrete.

摘要

Method for construction of a reinforced-concrete girder (P') with increased fire resistance, intended to resist a standardised theoretical fire for a given duration T, characterised in that, knowing a distribution in a cross-section of the girder (P') of a coefficient of resistance R of reinforcements of the girder (P') at the end of the said duration T of the standardised theoretical fire, the said coefficient R indicating a percentage of between 0 and 100% of the resistance of the reinforcements at normal temperature, the diameter of a longitudinal reinforcement (7, 8) arranged at a given point of the cross-section of the girder (P') is at a maximum (Dn) if the coefficient of resistance R at this point is greater than a limit value (Rn - 1), and at a minimum (D1) if the said coefficient of resistance R at this point is below another limit value (R1). IMAGE