Some useful construction tips for making foundation stronger
If it is required to provide supplementary loads, columns foundations should be strong enough to bear them. For this purpose, the foundations should be expanded and fortified through a concrete jacket that is built up to the prevailing footings. With the purpose of transmitting exact loads, the new jacket should be fastened perfectly to the prevailing footing and column neck. It is done by drilling holes into surviving concrete of footing and epoxy plastering the longitudinal reinforcement of jacket. The other useful process is to apply complete anchorage length for longitudinal reinforcement by spreading the column jacket at the top of footing.
If the bearing area of footing is inadequate, the size should be extended for the footing. The transmission of loads from column to footing becomes simpler when the column is also being jacketed. The size of the “jacket” is chosen in such a way that the average maximum foundation pressure remains under the suggested acceptable value. Proper care should be taken throughout construction so that the prevailing adjacent foundations are not affected by the excavations for the new “jackets”.
Due to the action of loads, a split of new concrete from the old concrete surface may occur. To get rid of this issue, a plethora of closed rings having adequate overlap or welded connection should be arranged around the footing.
In order to fortify an isolated footing, the size of the footing and the reinforcement steel bars should be extended with the following processes:
1. Excavating surrounding the footing
2. Cleaning and roughening the surface of concrete.
3. Arranging dowels at 25-30cm gapping in both directions by applying a proper epoxy material.
4. Anchoring the new steel bars with the dowels by steel wires. The diameter and number of steel bars should be based on the design.
5. Coating the footing surface using a bonding agent for obtaining the necessary bond among old and new concrete.
6. Pouring the new concrete prior to the bonding agent gets dried. The new concrete should comprise of a non-shrinkage material.
To gather more information, go through the following link