Prediction of creep strain in mineral wool slabs under compression

Laimutis Steponaitis, Sigitas Vėjelis

Abstract


In order to successfully use stone wool products as a construction material which is affected by long-term compressive loads, it is not enough to be aware of the strength and deformation characteristics determined under shortterm loads. It is important to know the change in time of deformations (creep deformations) of the products under
constant long-term compressive loads, which cause the enlarged deformations of structural elements of the material.
The analysis of the change in thickness of stone wool under constant short-term and long-term loads is presented, predicted values of creep deformations are determined and combined using synthesis procedure, impact factors for joint prediction results and weighted mean values of joint prediction results are determined. For the prediction of consistent pattern of creep deformations for the period of 10 years the relative creep deformations at the time t were used. These relative deformations under constant compressive stress were recalculated to single stress. It has been proposed to evaluate predicted creep deformations of stone wool slabs for any of the constant compressive stress, representing the time period up to 10 years, on the basis of values of creep mobility.


Keywords:
mineral wool, compressive strength, creep strain, prediction

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References


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DOI: 10.7250/iscconstrs.2014.30

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