The Compressometer/Extensometer for 4x8 Cylinders with Dial Gauge measures the average deformation and strain of concrete cylinders during compression testing for determination of modulus of elasticity. The instruments consist of two yokes, mounted around the specimen. The bottom one is rigidly attached, and the upper one is hinged at opposite points to permit pivoting. A third center yoke attaches to the specimen to measure horizontal extension. This allows a combined determination of both modulus of elasticity and Poisson’s ratio. A second dial between yoke segments measures the transverse deformation simultaneously.
Yokes are lightweight aluminum alloy; other parts are cadmium plated steel. A mechanical dial measures specimen deformation at the two opposite positions. The dial indicator has 0.2in (5.08mm) range and 0.0001in (.0025mm) divisions.
Meets ASTM C469.