.png)
SUB-STRUCTURE WORKS
BASEMENT STRUCTURE
Basement structures are are typical sub-structures or structures built below ground level, and are typically required in buildings with basement levels for various purposes such as parking, utilities or retail spaces. Basement structures usually incorporate the use of piling and diaphragm wall works.
Our Group employs both top-down and bottom-up construction methods in the construction of basement structures.
In a top-down construction method, diaphragm wall is first constructed to prevent the surrounding soil, rock and other materials from collapsing during excavation. Thereafter, piles will be bored into the ground serving as supporting beams in the basement structures, with basement slabs being placed on the piles to provide lateral support during excavation. Various openings are left on the slabs to allow access of machinery as well as removal of soil and wastes while excavation is carried out. The excavation process is continued until the bottom most position is constructed. Construction of structures above ground level can be carried out simultaneously while construction of basement structures is carried out.
.
On the other hand, in a bottom-up construction method, excavation is carried out until the predetermined length for the bottom most slab position is met. Earth retaining structures will be constructed as a temporary structure to hold the soil in place during excavation. The basement slab is then cast at the bottom most position, and the earth retaining structures are removed. Basement slabs will then be progressively cast until the upper most slab position is constructed.
PILE CAP
Pile cap refers to a thick layer of ready-mix concrete resting on piles that have been driven into the ground to provide a stable foundation. Pile caps usually form part of the foundation of a building, particularly for high-rise buildings or structures, or support bases for heavy equipment. The pile cap distributes the load of the building onto the piles. Steel reinforcement bars are also installed within pile caps for installation of structural columns above.
RAFT AND PAD FOUNDATION
Raft and pad foundations are types of shallow foundations, i.e. generally founding levels of less than three (3) metres from ground level. Raft and pad foundations generally serve as the foundation for low-rise buildings such as terraces, but it can also be used to form the foundation
for high-rise buildings that build on relatively solid ground.
A raft foundation extends across the entire loaded area so that loads from the entire structure are spread over a large area, in order to reduce the load bearing stress on the soil. Meanwhile, a pad foundation refers to a foundation that is intended for sustaining concentrated loads from a single point load such as structural column. It typically has a larger base than the single point load in order to spread the load from the single point load across a larger area, reducing the load bearing stress on the soil
.jpg)
