Title: Listeskrue 3,5x45.pdf
The coefficient of subgrade K may be calculated from the modulus of elasticity EHI and the thickness tHI of the heat insulation if the effective width wef of the heat insulation under compression is known. Due to the load extension in the heat insulation the effective width wef is greater than the width of the batten or rafter, respectively. For further calculations, the effective width wef of the heat insulation may be determined according to:wefw t HI/ 2Kwhere w = minimum width of the batten or rafter, respectively tHI = thickness of the heat insulation E tHIHIThe following condition shall be satisfied: M d W f m,d1f m,dm,dFor the calculation of the section modulus W the net cross section has to be considered.The shear stresses shall be calculated according to:V(F F )  s 2 bThe following condition shall be satisfied:  f v,d1,5 V  d A f d1v,dFor the calculation of the cross section area the net cross section has to be considered.