Executive Summary : | Fire protection measures for structural RC members are crucial for maintaining structural stability and integrity against collapse or failure. Current standard codes and practices lack design methodology, guidelines, and fire protection measures for structural fire safety, limiting their scope to fire-resistance rating using nominal concrete cover provisions for structural applications. The loss of designed load-carrying capacity in RC structural members under severe fire exposure conditions is primarily due to the thermally induced concrete and steel properties, which lead to loss of capacity and stiffness due to degradation of mechanical properties. The increasing deformation of RC members at concrete temperature can be observed more than 500 ºC due to transient creep strains of concrete. This continuous development at a constant heating rate under sustained loading conditions directly influences the stability of structural members and introduces large deformation and failure of RC members at fire load. Therefore, appropriate thermally induced concrete properties estimation, specifically transient creep strain, is crucial for fire resistance evaluation of RC members. The creep strain of concrete is a time-dependent phenomenon obtained under sustained loading on concrete samples in controlled environmental conditions. An additional form of Calcium silicate Hydrate (CsH) gel can minimize micro-meso level cracking formation, resulting in a slow rate of creep strain formation in concrete under sustained loading. However, this process reverses at elevated temperatures, leading to additional micro and meso crack formation in a concrete binding matrix. To overcome this problem in vast and severe fire load conditions, the challenge has been accentuated to mitigate the transient creep strain of concrete at elevated temperatures with a scientific solution for enhancing fire resistance rating. Guidelines for experimental measurement of the transient creep strain of concrete have also been targeted in this proposal. |