| 摘要 |
a top deck (5), a bottom deck (10) and at least two elongate bearers (15) securing the decks (5, 10) together. Each bearer (15) having a first portion (16) and a second portion (17), each portion (16, 17) extends separately between the decks (5, 10) and has a top web (20) and a bottom web (25) connected to a central web (30) by inclined portions (35). |
