Stress Measurement in Concrete Rebars

The test is performed on a reinforcement bar making part of a concrete structure. It consists in measuring the strain that occurs in the iron when the bar is cut.

In order to accurately measure the stress release strain , considering the expected low strain values, high precision instruments must be used, which are mounted on the rebar by special mechanic fixing clamps. This method does not heat or affect the iron in any way and, consequently, cannot induce any non-quantifiable self-stress.

The main characteristics of the tools used are the following:

• nominal stroke: ± 2.5 mm
• deviation from linearity: <± 0.05% of full scale
• measurement base length: 100 mm.