The core of the top-down technology is simultaneous construction of the above ground and underground parts of a building.
The technology is applied when it is impossible to construct the building by standard methods or there is a risk of loss of loadbearing properties of soil bases located close to the object under construction. That is why the Top-down technology is widely used in big cities with densely built-up areas. The technology allows increasing useful urban areas and their effective usage by building substructures.
The design of such a project requires high qualification of the specialists and experience of similar projects. The following controlling measures are taken during construction and assembly works: building structure shift, ground water level, reinforcement stress, deformations in concrete, anchor tension, strut stress.
- the lowest impact technology for the objects located in the area of new construction;
- getting the maximum volume of commercial space in the building under design by constructing substructures;
- less time for the project implementation compared to traditional building methods.
When constructing the object by Semi Top-down method the ground works are performed by the cut-and-cover method. The construction of above ground parts is held after completing the construction of substructures, not simultaneously.