Method for manufacturing a sound absorption structure comprising a cellular panel incorporating acoustic elements and sound absorption structure obtained using said method

A method for manufacturing a sound absorption structure comprising a cellular panel, a porous layer positioned on a first face of the cellular panel, a reflective layer positioned on a second face of the cellular panel and a plurality of acoustic elements positioned in the cellular panel, each acoustic element comprising a first chamber that has a first mouth closed by the porous layer so that it forms a first cavity, a second chamber in which the first chamber is positioned, closed so that it forms a second cavity, and at least one acoustic orifice passing through the first chamber, the method comprising the steps of:

• producing, for each acoustic element, a recess in the cellular panel that opens out onto the first and second faces of the cellular panel,
• inserting the acoustic elements into their recesses,
• laying an anchoring layer on the second face of the cellular panel,
• positioning a connecting system between an outer surface of the second chamber of each of the acoustic elements and at least one of the cellular panel and the anchoring layer,
• curing or polymerization at a first pressure allowing a connection of each acoustic element to at least one of the cellular panel or the anchoring layer,
• putting in place the porous layer and the reflective layer, and
• curing or polymerization at a second pressure allowing the porous layer and the reflective layer to connect to the cellular panel.