A chemical two-component mortar compound including a resin component (A) that contains at least one radically curable, ethylenically unsaturated compound (a) as the curable component, and including a separately arranged so as to inhibit reaction curing component (B) that contains a curing agent for the resin of the resin component (A), with improved adhesion to the surface of partially cleaned and/or moist holes in mineral substrates, characterized by a content of 0.2% to 10% by weight of at least one (meth)acryloxy alkyl trialkoxy siloxane and/or poly(meth)acryloxy alkyl silsesquioxane as an additional component (b) of the resin component (A); it also describes magazines, cartridges or plastic bags containing this chemical two-component mortar compound in two or more chambers that are separate from each other, in which the resin component (A) or the curing component (B) are arranged separately so as to inhibit a reaction; and it also describes its use to chemically fasten structural elements in mineral substrates.