N°186. 1988. Contributions to Technology and Quality Control of Reinforcement: Quality System for Concrete Reinforcement - Synthesis Report

There follow three studies carried out by several Task Groups of Permanent Commission VII, “Reinforcement: Technology and Quality Control.”

The first of these studies was written by Task Group VII/2, “Quality Control,” under the chairmanship of Dr. Russwurm, entitled “Quality System for Concrete Reinforcement.” It was presented at the Quality Control Session during the CEB Plenary Session in Rotterdam.

The Working Group was confronted with a series of problems of a fundamentally technical nature and recognized that nearly every country had developed very detailed specifications concerning the quality control of reinforcement. All these documents represent different approaches to quality control.

Consequently, the Working Group had to decide whether to establish a new document based on the lowest common denominator or to prepare a text reflecting the current state of knowledge in quality control. Due to legal and juridical considerations, it was decided that a new document should be prepared.

The Working Group is convinced that the presentation of the main principles of quality control of reinforcement is of greater importance than the compilation of different national specifications. It therefore attempted to free itself from juridical and economic constraints.

It was also decided that the paper should not consist solely of statistical considerations. The relevant background knowledge can be found in the literature.

The second study was written by Task Group VII/1, “Technical Requirements for Reinforcement,” under the chairmanship of Professor Delibes, entitled “Bond of Reinforcing Bars with Small Diameters Determined by the Pull-Out Test.”

In 1983, Permanent Commission VII of the CEB produced a revised version of the RILEM standard method for the pull-out test of reinforcing bars. It introduced an important modification for specimens with dimensions limited to 200 mm edge length, and restricted the application of the method to bar diameters of at least 10 mm. This made it possible to avoid the compaction difficulties of specimens requiring cubes with an edge length equal to ten bar diameters when small bars were tested.