Print Email Facebook Twitter Stress evolution in restrained GGBFS concrete due to autogenous deformation Title Stress evolution in restrained GGBFS concrete due to autogenous deformation: bayesian optimization of aging creep Author Liang, M. (TU Delft Materials and Environment) Li, Z. (TU Delft Materials and Environment) He, S. (TU Delft Materials and Environment) Chang, Z. (TU Delft Materials and Environment) Gan, Y. (TU Delft Materials and Environment) Schlangen, E. (TU Delft Materials and Environment) Šavija, B. (TU Delft Materials and Environment) Date 2022 Abstract Stress evolution of restrained concrete is a significant direct index in early-age cracking (EAC) analysis of concrete. This study presents experiments and numerical modelling of the early-age stress evolution of Ground granulated blast furnace slag (GGBFS) concrete, considering the development of autogenous deformation and creep. Temperature Stress Testing Machine (TSTM) tests were conducted to obtain the autogenous deformation and stress evolution of restrained GGBFS concrete. By a self-defined material subroutine based on the Rate-type creep law, the FEM model for simulating the stress evolution in TSTM tests was established. By characterizing the creep compliance function with a 13-units continuous Kelvin chain, forward modelling was firstly conducted to predict the stress development. Then inverse modelling was conducted by Bayesian Optimization to efficiently modify the arbitrary assumption of the codes on the aging creep. The major findings of this study are as follows: 1) the high autogenous expansion of GGBFS induces compressive stress at first hours, but its value is low because of high relaxation and low elastic modulus; 2) The codes highly underestimated the early-age creep of GGBFS concrete. They performed well in prediction of stress after 200 h, but showed significant gaps in predictions of early-age stress evolution; 3) The proposed inverse modelling method with Bayesian Optimization can efficiently adjusted the aging terms which produced best modelling results. The adjusted creep compliance function of GGBFS showed a much faster aging speed at early ages than the one proposed by original codes. Subject Autogenous shrinkageConcreteCreepEarly age crackingRelaxation To reference this document use: http://resolver.tudelft.nl/uuid:40e90135-7b6a-4ee4-857f-0c020dd95f92 DOI https://doi.org/10.1016/j.conbuildmat.2022.126690 ISSN 0950-0618 Source Construction and Building Materials, 324 Part of collection Institutional Repository Document type journal article Rights © 2022 M. Liang, Z. Li, S. He, Z. Chang, Y. Gan, E. Schlangen, B. Šavija Files PDF 1_s2.0_S0950061822003816_main.pdf 15 MB Close viewer /islandora/object/uuid:40e90135-7b6a-4ee4-857f-0c020dd95f92/datastream/OBJ/view