| 摘要 |
The building block has two internal longitudinal walls (17,18) situated adjacent the side walls (11,12) and with lower sections (17B,18B) extending downwardly beyond the lower edges of the side walls. There are lateral cavities (21,22) which are open at the bottom but closed at the top (13) and extending integrally along the length of the block between each side wall and the adjacent inner wall (17,18).
|
