求翻译：隔声墙由隔声模块板组合拼装而成。壳体材料为：钢质隔音模块，模块板内填充多层复合隔音材料，内层采用1.2mm镀锌钢板，2mm厚钢板做支持龙骨是什么意思？

Walls and held together by the sound insulation module plate combination. The shell material: steel soundproof module, the module board to fill the multi-layer composite insulation materials, the inner layer is made of 1.2mm galvanized steel 2mm thick steel plate to support the keel

Walls by acoustic Module Panel assembled. Material: steel shell for noise module, module GEM filled within multi-layer compound acoustic materials used in top 1.2 mm galvanized steel, 2mm steel plate keel do support

The soundproofing wall becomes by soundproofing mold block combination assembling.The shell material is: The steel sound-insulated module, in the mold block fills the multi-layered compound sound-proof material, the inner layer uses the 1.2mm galvanization steel plate, the 2mm steel plate does suppo

Sound insulation wall plate Assembly by the sound module. Shell material: steel sound module, module boards filled with Multilayer Composite soundproof material, inner layer made of 1.2mm zinc plated steel sheet, 2mm support medium and heavy plate keel