Shear strength and modulus of elasticity of expanded polystyrene (EPS)

Abstract

Expanded polystyrene (EPS) is used in layered elements, in which the EPS midlayer takes up a part of shear stresses. In such construction EPS provides the stability and rigidity of the whole structure. In the present paper shear strength and shear modulus elasticity are determined according to requirements of European norm EN 12090. Single and double specimen test methods were used in the experiments. The shear strength and shear modulus of elasticity were determined using EPS slabs manufactured in different Lithuanian enterprises. Expanded polystyrene slabs with density from 11 kg/m3 to 30 kg/m3 were used in the tests. On the basis of experimental data dependences between expanded polystyrene type and shear strength as well shear modulus are given. It is shown, that the thickness of the sample significantly influences shear strength and shear modulus of elasticity.

Polistireninis putplastis (EPS) daugiasluoksnėse pastatų atitvarose gali būti veikiamas šlyties įtempių. Kadangi EPS užtikrina visos konstrukcijos stabilumą, tai būtina tiksliai įvertinti šlyties įtempių poveikį termoizoliaciniam konstrukciniam polistireninio putplasčio sluoksniui. Stiprio ir tamprumo modulio šliejant bandymai atlikti pagal EN 12090 reikalavimus naudojant dvigubo bandinio bandymų schemą. Bandymams naudotas Lietuvos gamintojų pagamintas 12 kg/m3–35 kg/m3 tankio polistireninis putplastis. Gautos priklausomybės tarp polistireninio putplasčio tankio ir stiprio bei tamprumo modulio šliejant. Nustatyta EPS storio įtaka jo stipriui šliejant. Gautos polistireninio putplasčio regresinės priklausomybės gali būti panaudotos stipriui šliejant nustatyti pagal putplasčio tipą.