The way our houses are constructed is very important for us to assure the safety of our loved ones. It is necessary for us to know whether the foundation of our house is strong enough for holding the entire weight of a house or not. We know that the foundation is important for the structural integrity of our houses and any fault or defect in it can lead to a major problem.
For its proper repair, underpinning is the best solution. It can repair the faulty foundations before the condition becomes too sensitive and risky. In this article, we will be discussing the different methods by which these faulty foundations can be repaired.
Beam and Pile Method
The process of underpinning with the beams and pile is one of the best methods which can reduce the faults. In this method, one has to install the pile on either side of the affected wall. Once the pile is installed, then the brickwork below the wall is removed. After this, the piles are connected using the beam made up of reinforced concrete.
This gives support to the wall. If the distance between the beams is reduced then it will be able to handle a high load. The benefit of this method is that is fast and less disruptive to the affected area of the building. The quantity, size, shape, and diameter of the pile & beam are decided on the basis of the underlying stratum’s bearing capacity.
This procedure is the most commonly and conventionally used method of underpinning. It is suitable for the underpinning when the foundation is shallow. This one involves excavation of the weak soil below the surface.
The weak soil is then replaced by the concrete which is used for strengthening the base. Concrete is preferably used in the mass pour method as it can handle the weight of the entire structure effectively. The benefits of using this method are that it required less labor which decreases the cost of labor.
The pile raft foundations are for the huge structure and are used in situations when the soil is not suitable to stop the excessive settlement. The addition of raft to pile in this procedure increases the size of the foundation, which helps in resisting the horizontal loads. In this process, an optimum number of piles, their diameter and length are determined for making sure that the stability of the structure. The use of pile and raft together will ensure the stability of the buildings by providing an economical solution.
Screw Pile and Brackets
The screw pile and brackets are used for building the deep foundations in situations when the conventional underpinning is not possible. There are some buildings that require excavation up to greater depths which makes it impossible to use a piling rig. Therefore, in such circumstances, the screw pile and bracket is ideal for creating open access to work on the foundation.
This method makes it possible for the screw pile to work even if there are vertical or lateral winds. The screw pile and brackets can be installed by only two to three men and that too manually. It can also be used with the help of a mini excavator. It is necessary to make sure that the screw piles are used with the underpinning brackets. With this equipment the structure can be lifted up using the pile and bracket system.
Unconnected Pile Raft Foundation (UCPRF)
In this method, the piles are not linked to each other directly, and are separated with the help of a structure that acts as a cushion. This gap-like structure is filled with compacted soil and sand-gravel mixture. This gap helps in distributing the load equally between the raft and pile which makes it more efficient.
Precautions to be taken prior to Underpinning
It is necessary to be aware of the precautionary measures that are required to be taken before underpinning. It is very important to remove the load from the building. Start by removing all your belongings and furniture. Also, inspect the site that needs underpinning and the land adjacent to it properly. Underpinning is an effective method of handling home foundation-related problems. Henceforth, you should hire an experienced Underpinning contractor, who can go through the entire procedure properly.