design of metal, concrete, lightweight concrete, plaster, wood, holzfasermaterial, plastic, of a combination of materials o.dgl.

摘要

1514516 Laminates REDUC ACOUSTICS AB 30 May 1975 [30 May 1974] 23635/75 Headings B5N and B5P A structural element comprises first and second parts of the element separated from each other by a damping layer comprising viscoelastic material, the viscoelastic material extending discontinuously through the damping layer and joining the first and second parts of the element together, such that shearing is developed in the viscostatic material when said first and second parts vibrate in bending modes, the distance between adjacent spaced apart portions of the viscoleastic material being less than the wavelength of a frequency to be damped. In the embodiment shown in Fig. 2, two parts 1 and 2 of metal, concrete, plaster or wood fibre sheets are separated by a damping layer consisting of distributed lines or spots of viscoelastic material 4. In the embodiment of Figs. 3 and 4 an upper part 5 in the form of a framework structure, e.g. of wood is separated from a lower part 6, e.g. a concrete slab by a damping layer in the form of spots or patches 7 of viscoelastic material. Figs. 5 and 6 show an embodiment, where, in a monolithic structure, near the surface of one part 9 there is embedded the other part in the form of an array of reinforcing member shown as box-like girders 8, a layer of vise#astic material being applied to the members #allow for relative shear.