Comprehensive concrete fracture tests: Description and results

• The deep relative notched beam results agree closely with Bazant’s Type 2 size effect law and give initial fracture energy.
• The RILEM total fracture energy was calculated from the nearly complete post-peak softening load-displacement curves.
• The analysis of comprehensive fracture tests will give better understanding of the size effects on structure load capacity.
• The analysis will improve the design of concrete structures.

Although hundreds of concrete fracture tests exist, their evaluation is ambiguous because they have limited ranges of specimen size, initial notch depth and postpeak response, and refer to different concretes, different batches of concrete, different ages, different environmental conditions, different loading rates and test procedures, and different specimen types. Presented is an experimental investigation of unprecedented comprehensiveness and low scatter, using specimens made from one batch of concrete. It includes: (1) notched and unnotched beams tested at virtually the same age; (2) crack depths ranging from 0% to 30% of beam depth; (3) a broad size range (1: 12.5); (4) tests in transition between type 1 and type 2 size effects; (5) virtually complete postpeak softening data; (6) properly correlated loading rates; and (7) complete standard characterization of the concrete used. The analysis is relegated to a follow-up paper.