Concrete columns are used for carrying loads of a building. They transfer the same to a suitable soil bearing capacity. They carry loads horizontally, vertically and laterally. They can be erected as free standing, used for hanging gates. Alternatively they can be incorporated within the walls of a building structure. Concrete columns are made from steel and concrete cast in a form work. These are done in circular, rectangular or square shapes.
In erecting concrete columns the load to be carried is considered. This determines the size of column and type of reinforcement to use. The process of erection commences by setting up a base. A pit is first excavated to a suitable soil bearing capacity in depth. Blinding to the pit is done to protect the soil touching the steel reinforcements. When the base is cast, steel is exposed. This reinforcement is used as starter bars for the column.
Form work of the required column size is formed first aside. The already tied steel is joined together with the starter bars. This ensures the column starts from the ground upwards. The steel should be free from oils and rust. Use binding wire to tie together all steel. Its important to cast concrete in lifts. This should not exceed two thousand five hundred millimeters in height. When the steel work is complete, then form work assembly starts.
The form work for erecting a column is fixed by opening the sides. Its then slid to have the steel inside the box. Once the box is upright, the form work is then fastened and supported on all sides. Concrete is then poured and vibrated until it reaches the top of the box. It is left for seven days. Curing is done from the top. After seven days the form work is then removed to expose the cast column. This is continuously cured for another Seven days.