Comparison of calculation models’ estimates with actual measured autogenous shrinkage in High-Performance Cement Composites

摘要

There are several calculation models for estimation of shrinkage in concrete. The most popular ones are: ACI-209R-92 method, Ba?ant-Baweja model (B3), Gardner’a-Lockman’a model (GL 2000), CEB-FIP (CEB MC90-99), Spanish model (EHE), EuroCode method (EC-2) from 2004 and Tazawa–Miyazawa model (JSCE). Majority of aforementioned models do not include the deformation caused by the autogenous shrinkage. The methods assume the total deformation as a result of drying shrinkage action. Additionally, a non-standard method was proposed by Jonasson and Hedlund. However it only is used to determine the autogenous shrinkage of High-Performance Concretes (HPC). Tazawa-Miyazawa model and Jonasson-Hedlund method are based on the proportions and material properties such as water/cement ratio, water/binder ratio, type of the cement, or start of setting time. In contrary, the CEB MC90-99 and EC-2 models correlate the autogenous shrinkage with the overall compressive strength of concrete. The article presents the analysis of various calculation models in comparison to actual measurements. The autogenous shrinkage was measured in four cement composites starting at casting up till 28 days of curing.