Shrinkage-induced deformations and microcracking in structural concrete - monitoring, modeling and identification
Motivation
Time-dependent behavior of concrete structures is inherently connected with shrinkage and creep. Kinetics of these processes is influenced not only by the material properties, but also by the specimen size and type of loading. The currently most advanced material model based on the Solidification theory and microprestress does not capture these processes correctly, e.g. it exhibits the opposite size effect on drying creep. Development and calibration of the improved material model is not possible without a comprehensive experimental dataset utilizing specimens from a single concrete batch. Such dataset will help to split the total deformation into individual components and to determine their evolution. This project offers newly-developed structural-scale experiments on unloaded specimens exposed to non-uniform drying. The time evolution of deformation and cracking will be monitored by means of DIC and laser measurements. The improved material model will be subjected to the sensitivity analysis and its material parameters will be determined using robust optimization algorithms.
Project objectives
- experimental investigation of shrinkage, creep and tensile cracking of non-symetrically drying concrete specimens
- comparison of two modern experimental methods
- validation of the developed material model and its parameters identification.
Project outputs
Journal papers
- I. Aldellaa, P. Havlásek, M. Jirásek, P. Grassl: Effect of creep on corrosion-induced cracking. Engineering Fracture Mechanics, 264 (2022)
- P. Havlásek, V. Šmilauer, L. Dohnalová, R. Sovják: Shrinkage-induced deformations and creep of structural concrete: 1-year
measurements and numerical prediction. Cement and Concrete Research, 144 (2021).
- V. Nežerka, P. Havlásek: A Lightweight DFT-Based Approach to the Optical Measurement of Displacements Using an Open-Source Python Code. Experimental Techniques (2021)
- F. Kanavaris, A. Jędrzejewska, I. Sfikas, D. Schlicke, S. Kuperman, V. Šmilauer, T. Honório, E. M.R. Fairbairn, G. Valentim, E. Funchal de Faria, M. Azenha: Enhanced massivity index based on evidence from case studies: Towards a robust pre-design assessment of early-age thermal cracking risk and practical recommendations. Construction and Building Materials, 271 (2021).
- V. Nežerka, P. Havlásek, J. Trejbal: Mitigating inclusion-induced shrinkage cracking in cementitious composites by incorporating recycled concrete fines. Construction and Building Materials, 248 (2020).
- V. Šmilauer, P. Havlásek, T. Gasch, A. Delaplace, D.E.-M. Bouhjiti, F. Benboudjema, M. Briffaut, F. Kanavaris, M. Azenha: Hygro-mechanical modeling of restrained ring test: COST TU1404 benchmark. Construction and Building Materials, 229 (2019).
Conference papers
- V. Šmilauer, P. Havlásek, P. Reiterman, P. Huňka: Crack Control of Upstream Polder Face Using Calibrated Thermo-mechanical Simulations.International RILEM Conference on Early-Age and Long-Term Cracking in RC Structures. CRC 2021. RILEM Bookseries, vol 31. Springer, Cham.
- L. Dohnalová, P. Havlásek, V. Šmilauer, P. Reiterman, V. Davidová: Size effect on the ultimate drying shrinkage of cement mortar: 1-year experiment and numerical modeling. Acta Polytechnica CTU Proceedings. vol. 30, 1-6.
- P. Horák, P. Havlásek: Modeling time-dependent deformations of concrete members subjected to symmetric and asymmetric drying. Acta Polytechnica CTU Proceedings. vol. 30, 24-29.
- L. Dohnalová, P. Havlásek: Size effect on the ultimate drying shrinkage of concrete - experimental evidence and engineering practice. Acta Polytechnica CTU Proceedings. vol. 26, 13-18.
- L. Dohnalová, P. Havlásek: Size effect on the ultimate drying shrinkage of concrete - modeling with microprestress-solidification theory. Engineering mechanics 2020, Proceedings Vol. 26 (2020), 122-125.
Experimental database