Let me give you an overview over the steps to U-Mark final certification, just to explain why some of the information is needed now:
-We prepare a test program for determination of resistance of the system (that’s what I do right now).
-DIBt will check the program.
-Based on this program we will send you an offer for the tests and the evaluation
-Tests will be performed and evaluated. Two documents will be prepared: a test report and an expertise.
-DIBt will check the documents and prepare the approval. The approval will list the resistance/strength values, but also requirements for the production control and the materials used.
The approval is the base of the certification. The following certification has to show that the requirements stated in the approval are fulfilled. The idea is that, if these requirements on production control and materials are fulfilled, the product can be used and the resistance values stated in the approval apply. In this sense, the Ü-mark is quite similar to the CE-mark as introduced in the Construction products directive (but not as given in some other directives).
-A certification and monitoring contract between KIT and the producer will be prepared.
-An audit in the manufacturing places will be done and the factory-own production control will be checked. Random tests on samples (usually material tests) will be done.
-A report will be issued
-If everything is o, the certificate will be issued.
Now back to my questions:
They all refer to the fist point in the above list. For the testing program, we need to know, which forces act on the system. The actual value of force is not required. Just to include a test for determination of the force in our program. And about the alternatives in materials: Different materials will lead to different strength values for the systems. If different materials are used, we have to test these. As far as I understood, we do not have to deal with different alternative materials right now. Alternatives are only discussed for the spacer brackets which are not covered (as stated below). Regarding stiffness: There might be the request to calculate deflections and defrmations. Therefore not only strength, but also stiffness has to be determined in the tests.
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