The Top-down method is mainly used for two types of urban structures, tall buildings with deep basements and underground structures such as car parks, underpasses and subway stations. The higher-level slabs are cast before the lower-level slabs to act as horizontal frames for wall support as the excavation progresses. Top-down is defined by the use of the permanent internal structure as the temporary propping to the retaining wall, cast in a top-down sequence. Description of Top-down construction method The Top-down construction method is the solution to these problems. Though this conventional method, also called a bottom-up method, is simple in both design and construction, it is not feasible for the projects with limited construction time or with site constraints (size of location, legal issues, etc). In most common construction methods, buildings with underground parts are built by the bottom-up method where sub-structure and super-structure floors are constructed sequentially from the lowest level of basement to the top of the building.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |