Modeling blended cement concrete tensile creep for standard ring test application

Abstract

The tensile creep of concrete with supplementary cementitious materials (SCMs) such as fly ash (FA) and ground granulated blast furnace slag (GGBFS) is investigated in this paper. A total of 21 series of tensile creep tests using dog‐bone specimens under uniaxial tensile loading have been carried out. The cement replacement rates considered were 30% fly ash, 40% and 60% GGBFS. The characteristic compressive strength of concrete was ranging from 25 to 100 MPa. The tests were conducted from the age of 2 days until 28 days. It is observed that the tensile creep of fly ash concretes was slightly lower than that of the reference mixtures without SCM. For GGBFS concrete, the higher the GGBFS content, the higher the tensile creep. Existing creep models, originally developed for creep in compression, could not predict the experimental tensile creep results. Thus, a new tensile creep model was proposed including creep prediction for concrete with fly ash and GGBFS. The new model was calibrated only for controlled environmental conditions (23°C and 50% RH) and has been validated by analyzing the development of concrete tensile stress in the restrained ring test.

Early-Age Cracking of Fly Ash and GGBFS Concrete Due to Shrinkage, Creep, and Thermal Effects: A Review

“…The validity of the proposed model was affirmed through validation against experimental results conducted by Ji et al [91] and Atrushi [92]. Zhang et al [93] proposed a tensile creep model for FA and GGBFS concrete based on specific test conditions (23 • C and 50%). They successfully verified the applicability of the proposed model for estimating tensile stress during the restrained shrinkage ring test.…”