Microstructured Polymers and Their Influences on the Mechanical Properties of PCC
Concretes are modified with polymers in order to improve their durability and adhesive strength. However, polymer-modified cementitious materials exhibit lower elastic moduli and higher viscous and plastic deformations in comparison to unmodified systems. The macroscopic properties are governed by microstructural changes in the binder matrix, which consists of both cementitious and polymer components. Herein, different pure polymer specimens and microstructured polymers were characterized using specific load tests and nanoindentation in order to better understand the microscopic origin of the macroscopic deformation behavior and ultimately the mechanical properties of PCC. The link between the micromechanical and macroscopic properties is established using a continuum micromechanics approach. Multiscale models aiming at the prediction of the deformation behavior of polymer-modified cementitious materials are developed with input parameters that are partially obtained from the experimental investigations. The comparison of the modeling results with the experimentally determined deformations is satisfactorily good, underlining the predictive capability of the modeling approach. The improvement of prediction models is crucial for the application of PCC for construction purposes and will encourage their integration into guidelines.
This research has been supported by the German Research Foundation (DFG) through Research Training Group 1462, which is gratefully acknowledged.
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