New approach for determining the shear modulus of insulating materials - Contribution to the design of sandwich elements

摘要

The decisive factor for the economic design of a reinforced concrete sandwich element is the realistic determination of the deformations and distribution of the internal forces. For this determination, the accurate knowledge of the insulating material properties is an important factor. The material behavior for the insulating material used was analyzed under pressure and shear stress by means of extensive experimental investigations. It has been found that the determination of shear strength as well as of shear modulus is not clear and thus, in accordance with the standard, unsatisfactory. For sandwich elements, a shear modulus that is too big or small will lead to incorrect results in the determination of deformations and the distribution of internal forces. Therefore, a new approach for determining the shear modulus for an insulating material was developed. This new procedure also provides useful values which can e.g. represent stress and deformation limits and thus optimize the design of sandwich elements.