Stress redistribution of concrete prisms due to creep and shrinkage: longterm observations and analysis
 Author
 Pieterjan Criel (UGent) , Robby Caspeele (UGent) , Nicky Reybrouck (UGent) , Stijn Matthys (UGent) and Luc Taerwe (UGent)
 Organization
 Abstract
 In 1979, 16 concrete prisms with dimensions 140x150x4000 mm were casted in the Magnel Laboratory for Concrete Research. These prisms differ by the amount of passive reinforcement and by the applied loading level. Four reinforcement ratios were considered, i.e. 0%, 1.5%, 3% and 6%. For each reinforcement ratio a prism was subjected to an axial load corresponding to a concrete stress of 0, 5, 10 or 15 MPa. The combination of both parameters results in a total of 16 specimens. The compressive stress was applied to the prisms by means of posttensioned unbonded strands at an age of 28 days. The stress level was kept constant during the first 12 years of the experiment by readjusting the force in the strands when the deviation exceeded 2% of the initial value. Afterwards, no readjusting of the strands took place. Significant redistribution of the stresses between the concrete and the steel can be expected due to the creep and shrinkage of concrete. This redistribution is larger for the prisms with a higher reinforcement ratio, resulting in lower creep and shrinkage strains. The timedependent response of these prisms was modelled taking into account the prestress losses and stress redistribution between the concrete and the steel. For reasons of numerical efficiency, the compliance function was approximated by a Dirichtlet series using continuous retardation spectra. A comparison between the predicted results and the measurements is given for two prisms.
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Please use this url to cite or link to this publication: http://hdl.handle.net/1854/LU6958781
 Chicago
 Criel, Pieterjan, Robby Caspeele, Nicky Reybrouck, Stijn Matthys, and Luc Taerwe. 2015. “Stress Redistribution of Concrete Prisms Due to Creep and Shrinkage: Longterm Observations and Analysis.” In CONCREEP 10: MECHANICS AND PHYSICS OF CREEP, SHRINKAGE, AND DURABILITY OF CONCRETE AND CONCRETE STRUCTURES, ed. Christian Hellmich, Bernhard Pichler, and Johann Kollegger, 138–146.
 APA
 Criel, Pieterjan, Caspeele, R., Reybrouck, N., Matthys, S., & Taerwe, L. (2015). Stress redistribution of concrete prisms due to creep and shrinkage: longterm observations and analysis. In C. Hellmich, B. Pichler, & J. Kollegger (Eds.), CONCREEP 10: MECHANICS AND PHYSICS OF CREEP, SHRINKAGE, AND DURABILITY OF CONCRETE AND CONCRETE STRUCTURES (pp. 138–146). Presented at the 10th International Conference on Mechanics and Physics of Creep, Shrinkage, and Durability of Concrete and Concrete Structures (CONCREEP).
 Vancouver
 1.Criel P, Caspeele R, Reybrouck N, Matthys S, Taerwe L. Stress redistribution of concrete prisms due to creep and shrinkage: longterm observations and analysis. In: Hellmich C, Pichler B, Kollegger J, editors. CONCREEP 10: MECHANICS AND PHYSICS OF CREEP, SHRINKAGE, AND DURABILITY OF CONCRETE AND CONCRETE STRUCTURES. 2015. p. 138–46.
 MLA
 Criel, Pieterjan, Robby Caspeele, Nicky Reybrouck, et al. “Stress Redistribution of Concrete Prisms Due to Creep and Shrinkage: Longterm Observations and Analysis.” CONCREEP 10: MECHANICS AND PHYSICS OF CREEP, SHRINKAGE, AND DURABILITY OF CONCRETE AND CONCRETE STRUCTURES. Ed. Christian Hellmich, Bernhard Pichler, & Johann Kollegger. 2015. 138–146. Print.
@inproceedings{6958781, abstract = {In 1979, 16 concrete prisms with dimensions 140x150x4000 mm were casted in the Magnel Laboratory for Concrete Research. These prisms differ by the amount of passive reinforcement and by the applied loading level. Four reinforcement ratios were considered, i.e. 0\%, 1.5\%, 3\% and 6\%. For each reinforcement ratio a prism was subjected to an axial load corresponding to a concrete stress of 0, 5, 10 or 15 MPa. The combination of both parameters results in a total of 16 specimens. The compressive stress was applied to the prisms by means of posttensioned unbonded strands at an age of 28 days. The stress level was kept constant during the first 12 years of the experiment by readjusting the force in the strands when the deviation exceeded 2\% of the initial value. Afterwards, no readjusting of the strands took place. Significant redistribution of the stresses between the concrete and the steel can be expected due to the creep and shrinkage of concrete. This redistribution is larger for the prisms with a higher reinforcement ratio, resulting in lower creep and shrinkage strains. The timedependent response of these prisms was modelled taking into account the prestress losses and stress redistribution between the concrete and the steel. For reasons of numerical efficiency, the compliance function was approximated by a Dirichtlet series using continuous retardation spectra. A comparison between the predicted results and the measurements is given for two prisms.}, author = {Criel, Pieterjan and Caspeele, Robby and Reybrouck, Nicky and Matthys, Stijn and Taerwe, Luc}, booktitle = {CONCREEP 10: MECHANICS AND PHYSICS OF CREEP, SHRINKAGE, AND DURABILITY OF CONCRETE AND CONCRETE STRUCTURES}, editor = {Hellmich, Christian and Pichler, Bernhard and Kollegger, Johann}, isbn = {9780784479346}, language = {eng}, location = {Vienna, Austria}, pages = {138146}, title = {Stress redistribution of concrete prisms due to creep and shrinkage: longterm observations and analysis}, year = {2015}, }