No. PCA/ACI do not offer free full PDFs. They sell the PDF or hardcopy. A few sample chapters may be free for review.
For structural engineers, concrete designers, and students, the "Notes on ACI 318-14 Building Code Requirements for Structural Concrete" is an indispensable resource. Often referred to simply as the PCA Notes (Portland Cement Association), this guide bridges the gap between the rigid requirements of the code and practical structural design application. pca notes on aci 31814 pdf link