Ceramic road marker compression and flexural strength testing to ASTM 4280

Case study

Ceramic road marker compression strength test to ASTM 4280

Ceramic road marker flexural strength test to ASTM 4280

Solution

Software-controlled force test system and software
Custom-made self-adjusting compression and flexure fixtures

Benefits

Software control to apply the ASTM standard procedure and internal standards
Multiple tests performed on one machine
Ability to measure high loads from the twin-column tester and compensate for machine deformation

Requirement

Saudi Ceramics manufacture non-reflective road markers for indicating traffic lane delineation, shoulders and other direction markings. Their Ceramic Road Markers (CRM) are produced in white and yellow and an advantage of this production method is the longevity of the colour as opposed to painting techniques. ASTM D4280 provides a complete standard specification for this specific extended life type, nonplowable, raised reflective design. Two types of functional strength tests are included in the standard; compressive and flexural. Both tests specify high loading which the marker must withstand:

the compressive strength test requires a deformation of less than 3.3 mm (0.13 in) when subjected to an equivalent representative load in service, and
the longitudinal flexure strength test specifies withstanding of 8914 N (2000 lbf).

Solution

Mecmesin supplied a high-capacity MultiTest twin-column test stand to perform both tests. The ASTM standard indicates particular attributes for the fixture, notably elastomeric pads positioned above and below the marker specimen to prevent localised surface fracturing.

Custom fixtures were produced to appropriately apply the loading to the circular, domed markers. Three specimens of each type are tested, with EmperorTM software capturing the force and displacement data plus the point of fracture. If any of the test pieces prematurely fail, the whole batch must be rejected. The twin-column machine is able to exert forces up to the established safe maximum threshold to enable confidence in the structural integrity of the batch.

The software’s graphical output enables the flexure criteria to be checked at the recommended loading. This powerful compression testing system enables Saudi Ceramic to test their products to rigorous quality standards and maximise life expectancy.