Reference: Mette Geiker, Dale P. Bentz and Ole Mejlhede Jensen, American Concrete Institute Special Publication 218, High Performance Structural Lightweight Concrete, John P. Ries and Thomas A. Holm, eds., pp 143-154 (2004).

Go back to Part I Chapter 8 Sec. (1) Go back to Table of Contents

Next: Introduction


Mitigating Autogeneous Shrinkage by Internal Curing

 

Mette Geiker, Technical University of Denmark, Denmark
Dale P. Bentz, National Institute of Standards and Technology, USA
Ole Mejlhede Jensen, Aalborg University, Denmark

Abstract

The use of internal curing is a highly effective means of mitigating autogenous shrinkage in cement mortars (w/s=0.35, 8 % silica fume). Two different sources of internal water supply are compared: 1) replacement of a portion of the sand by saturated low-density fine aggregate and 2) the addition of superabsorbent polymer particles (SAP). At equal water addition rates, the SAP system is seen to be more efficient in reducing autogenous shrinkage at later ages, most likely due to a more homogeneous distribution of the extra curing water within the three-dimensional mortar microstructure. A comparison of the water distribution in the different systems, based on computer modeling and direct observation of two-dimensional cross sections, is given.



Go back to Part I Chapter 8 Sec. (1) Go back to Table of Contents