EN12090 - Determination of Shear Behavior of Thermal Insulation Products

This European Standard specifies the equipment and procedures for determining the shear behavior. It is applicable to thermal insulating products used in building applications.

The tests described in this standard do not determine pure shear behaviour, but measure the effects of applying two opposite parallel forces to the major faces of the test specimen. The application of a force tangentially to the major surface of the test specimen is considered to represent more closely the stresses imposed upon thermal insulation products in many building applications, particularly walls, than other methods of measuring shear performance, e.g. bending tests.

In principle there are two methods of tests, both in a shear mode:

• Single test specimen arrangement
• Double test specimen arrangement

Single test specimen arrangement

The test machine exerts longitudinal shear forces through two parallel plates bonded to a single test specimen. The parallel plates are mounted to tension coupling mounted to the load cell and the base adaptor of the test machine. This flexibility takes care of the effect of specimen varied thickness.

Test specimen size: (L) 250mm (W) 50mm (T) 100mm

Double test specimen arrangement

The test machine exerts longitudinal shear forces through three parallel plates bonded to a double test specimen. The parallel plates shall be rigid, with the outer plates attached to a fixed mounting to the base of the test machine and the central plate to a tension coupling mounted to the load cell of the test machine.

Test specimen size: (L) 200mm (W) 100mm (T) 100mm

We suggest using a tensile testing system of dual-column design together with the appropriate test fixture according to the testing standard.

For this test, we use the specimen protect feature of Bluehill when loading the specimen and fixture into the machine. This is to prevent any overloading of specimen during this process prior to test. We then in the test method drive to a preload to eliminate any slack in the specimen, then at a constant speed of the crosshead of 3mm/min until a failure occurs. it is important to have a high-speed intelligent test data sampling rate of 100 Hz to the PC ensure the capture and record of shear strength and shear modulus.

We recommend using Bluehill test software package to input specimen parameters, set the desired speed control, automatically calculate the desired results and statistics, and finally to product a test report or send to a network database.

We suggest reviewing EN12090 to fully understand the test fixture and results requirements prior to performing any tests.