DIN EN 1156:2013-10

This European Standard specifies a method of determining in a constant climate both a duration of load factor and a creep factor for wood-based panels stressed in flatwise bending with and without a shear component. Knowledge of the duration of load factor is necessary to modify the characteristic values obtained in short-term tests in order to derive long-term values. Determination in a constant climate of the load duration factor (loss in strength with time under load) and the creep factor (ratio of increase in deflection with time to the initial elastic deflection) in bending by applying and sustaining a constant moment over the central region of a test piece. Both the time to failure, and the increase in deflection with time are measured. An alternative but provisional method employing medium sized test pieces is given in Annex A. This method can also be used for test pieces loaded under varying climates. With regard to DIN V ENV 1156:1999-03, the prestandard status has been changed to that of a full standard and the accuracy of the deflection measurement has been changed from 0,001 mm to 0,01 mm. The committee responsible for this standard is NA 042-02-15 AA "Holzwerkstoffe - Spiegelausschuss zu CEN/TC 112 und ISO/TC 89" ("Wood-based panels - Mirror Committee of CEN/TC 112 and ISO/TC 89") at DIN.