Research & Development Information PCA R&D Serial No. 2625 Internal Relative Humidity, Drying Stress Gradients, and Hygrothermal Dilation of Concrete by Zachary Charles Grasley Portland Cement Association 2003 © Zachary Charles Grasley _______________________________ Zachery C. Grasley University of Illinois 2151 Newmark Civil Eng. Lab 205 N. Mathews Urbana, IL 61801