The configuration of the test joint specimen that enables exposure of the sealant to a continuous degree of extension and compression in a single specimen is shown in Fig. 1. Details of this test specimen have been described elsewhere . This specimen has a fulcrum at the center that allows rotation of the support elements around an axis perpendicular to the support plate (this specimen has also been adopted in the development of a RILEM Technical Recommendation; further details regarding the test specimen are described in Ref. ). After the sealant is cured, a 30 % extension spacer is set at one end of the test joint so that the other end of the joint is subjected to 30 % compression (movement exposure
is given here as a percentage of the original joint width, as in ISO 8340 ). The center of the dynamic specimen is exposed to a movement of ±1.5 % due to the displacement between the rotary pin and the edge of the specimen. The change of the extension or compression position proceeds in intervals through the extension spacer’s placement at the other end of the test joint (see Fig. 2).