Construction services

Foundation footings part 2

Concrete and reinforced concrete footings are usually made on site. The bottom reinforcement of reinforced concrete footings consists of mesh made of steel bars. Covering the bars with concrete from the bottom and sides of the foot, due to their protection against corrosion, should not be present from 5 cm.

If a reinforced concrete slope is connected to the foot, it is from the foot that should lead to the number of reinforcement bars, how many bars are there in the column and of such length, to ensure the required column restraint.

In the footings for steel columns, sockets are left for the subsequent seating of anchor bolts or anchor bolts are set in the footing before it is concreted. The anchor bolts in the left slots are usually concreted after the column base is adjusted. The foot connected to the steel pole is shown in the figure.

tmp217f-1A foot for a steel pole; 1 - concrete footing, 2 - steel column base, 3 - Anchor bolt.

Prefabricated reinforced concrete footings are then made, when their dimensions and weight (time) they are not too big and it is possible to transport and install them with devices available on the site.

tmp217f-2Socket foot: a) side view, b) section, c) horizontal projection; 1 - foot, 2 - pole, 3 - concrete filling.

Under the poles, mainly prefabricated reinforced concrete, the so-called. "Cup" reinforced concrete feet. The base of the column is placed in the "chalice", and then after fine-tuning the position of the pole, the space between the foot and the pole is filled with concrete. The "cup" of the foot should be so designed, so that it does not tear apart. For this purpose, a reinforcement made of steel bars is placed around the "socket".