A sound absorbing structure includes a perforated surface with a plurality of through-holes, a first cavity that has a portion extending non-parallel to a normal direction of the perforated surface, the first cavity being breathable between an interior and exterior of the first cavity via the plurality of through-holes existing in a first region of the perforated surface, and a second cavity that is breathable between an interior and exterior of the second cavity via the plurality of through-holes existing in a second region adjacent to the first region of the perforated surface.

Embodiments relate to a plastic wall panel, comprising a hollow body having external walls and defining an internal cavity. The external walls include: a first major side wall, a second major side wall opposite the first major side wall, a minor top wall, a minor bottom wall, a first minor end wall and a second minor end wall opposite the first minor end wall. The minor top wall and the minor bottom wall each define mating structure to mate and align with another adjacent panel so that multiple panels can be tiled together to form at least part of a sound attenuation barrier. The hollow body defines a passage extending between the first and second major side walls and through the first and second minor end walls to receive a reinforcing beam.

A stiffener member for a hollow elongate panel. The hollow elongate panel may include a first end wall having a groove formation formed by a pair of inner walls and extending a length of the hollow elongate panel. The groove formation may extend into the hollow elongate panel. The stiffener member may include a bight member having opposing ends; a pair of arm members respectively extending from one of the opposing ends of the bight member to provide a substantially U-shaped configuration; and a flange member extending from each of the pair of arm members. The flange member may extend inwardly to abut one of the pair of inner walls of the groove formation when the stiffener member is received within the hollow elongate panel.

A sound wall and a method of constructing the sound wall. The sound wall includes a pair of laterally spaced posts, at least one of the pair of posts including: an elongate central member, a flange extending form the elongate central member in a direction substantially normal to the elongate central member, and a fin extending from the central member. The central member, the flange, and the fin may define a cavity for receiving elongate panels. The sound wall may include a plurality of elongate panels extending between the laterally spaced posts and stacked in an elongate direction of the elongate central member. End regions of the respective elongate panels may be retained between the flange and the fin. The sound wall may include an elongate stiffener member positioned within at least one of the plurality of elongate panels.

A sound wall and a method of constructing the sound wall. The sound wall includes a pair of laterally spaced posts, at least one of the pair of posts including: an elongate central member, a flange extending form the elongate central member in a direction substantially normal to the elongate central member, and a fin extending from the central member. The central member, the flange, and the fin may define a cavity for receiving elongate panels. The sound wall may include a plurality of elongate panels extending between the laterally spaced posts and stacked in an elongate direction of the elongate central member. End regions of the respective elongate panels may be retained between the flange and the fin. The sound wall may include an elongate stiffener member positioned within at least one of the plurality of elongate panels.

The invention relates to anti-noise installation for a guided transport track having a U-shaped cross section, the two branches of which form the lateral walls (15, 16) of the track and the central zone of which, connecting the two branches, forms at least one runway (18) for a guided transport vehicle (50), characterised in that said installation comprises a plurality of acoustic panels (30, 31, 34, 35, 38, 39) arranged relative to one another so as to form at least one chamber (20) for confining the noise resulting from the passage of a vehicle (50) over at least one runway (18), which chamber can be provided around said noise source while extending as far as a free end of at least one branch of the U, each panel (30, 31, 34, 35, 38, 39) forming at least one portion of a partition of a noise-confinement chamber (20).

A sound wall and a method of constructing the sound wall. The sound wall includes a pair of laterally spaced posts, at least one of the pair of posts including: an elongate central member, a flange extending form the elongate central member in a direction substantially normal to the elongate central member, and a fin extending from the central member. The central member, the flange, and the fin may define a cavity for receiving elongate panels. The sound wall may include a plurality of elongate panels extending between the laterally spaced posts and stacked in an elongate direction of the elongate central member. End regions of the respective elongate panels may be retained between the flange and the fin. The sound wall may include an elongate stiffener member positioned within at least one of the plurality of elongate panels.

The sound absorbing board includes a body and multiple sound absorbing elements. The body has a first side surface and a second side surface. The multiple sound absorbing elements are formed on the body at spaced intervals, and each one of the multiple sound absorbing elements has a protrusion, a groove, and two sound absorbing openings. The protrusion is formed on the first side surface of the body. The groove is formed on the second side surface of the body and has multiple concave portions and at least one convex portion. The multiple concave portions are formed on a bottom surface of the groove. The at least one convex portion is formed on the bottom surface of the groove, and is formed between two adjacent ones of the multiple concave portions. The two sound absorbing openings are formed on the two opposite side surfaces of the protrusion, respectively.

A sound absorber includes cavities mutually different in at least one of shape and size. A wall of a first cavity included in the cavities includes a first region and a second region. Through- holes connecting an interior to an exterior of the first cavity is formed in the first region. No through-holes connecting the interior and the exterior of the first cavity is formed in the second region adjacent to the first region. A wall of a second cavity included in the cavities includes a third region and a fourth region. Through-holes connecting an interior to an exterior of the second cavity is formed in the third region. No through-holes connecting the interior and the exterior of the second cavity is formed in the fourth region adjacent to the third region. Size of through-holes in the first region is different from size of through-holes in the third region.

A stiffener member for a hollow elongate panel. The hollow elongate panel may include a first end wall having a groove formation formed by a pair of inner walls and extending a length of the hollow elongate panel. The groove formation may extend into the hollow elongate panel. The stiffener member may include a bight member having opposing ends; a pair of arm members respectively extending from one of the opposing ends of the bight member to provide a substantially U-shaped configuration; and a flange member extending from each of the pair of arm members. The flange member may extend inwardly to abut one of the pair of inner walls of the groove formation when the stiffener member is received within the hollow elongate panel.