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Underpinning – All you need to know
The process of strengthening and repair of building foundations is known as underpinning. A situation might arise when the foundation may unexpectedly fail after completion. There has to be a remedial method in such an emergency. Hence underpinning may be applied to reinforce the foundations of an already existing structure. The underpinning method includes installing temporary or permanent support to the failing/weak foundation to achieve extra depth and bearing capacity.
An engineer may suggest underpinning for stabilization of a substructure due to numerous reasons. Typically timber piles are used as a foundation for buildings. A fluctuation in the water table causes degradation of these timber piles, which in turn causes settlement. The rise and collapse of the water table repeatedly also lower the bearing capacity of the soil, making the establishment settle. Building a structure over on soil whose bearing capacity is not suitable will inevitably cause the erection to pay over time. Hire professionals from https://www.restumpingunderpinningexperts.com.au to get the best outcomes.
The types of methods of underpinning include the following:
Expert observation is needed to conclude the decision on the underpinning requirement. When an already erected building shows changes through any distress or settlement, it is necessary to initiate offset as well as vertical level readings timely. The time determines the severity of the payment. Before excavation, professionals closely examine and judge the soil capacity. Based on the result of this test, determine whether underpinning is needed or not.
- The Pit Method or the Mass Concrete Underpinning Method
It is the most traditional underpinning method, followed over the centuries. It involves the extension of the older foundation until it arrives at more stable strata. Carry out controlled excavation under the already existing footing through stages. Upon reaching a suitable stratum, this excavation is filled with concrete. A new structure helps transfer the load from the old foundation to the newer one. This method is the low-cost ad you may use for shallow foundations. Complex foundation-related problems require superior methods.
- Cantilever Needle Beam Method of Underpinning
It is an extension of the pit method. You may apply this method if the plan has a substantial interior column and the foundation requires only a partial extension on one side.
- Pier and Beam Method
Also known as the base and beam method, it got implemented post the second world war. This method has the upper hand over the mass concrete method as it works well for foundations with tremendous depth. It is suitable for almost all ground conditions. In this method, concrete beams get reinforced to transfer the load. There are other methods, too, and one can choose as per expert guidance.
Whichever method of underpinning is applied to strengthen a foundation; each involves a similar idea. This basic idea is to extend the existing footing either breadthwise or lengthwise and lay over more vital soil strata.
It ensures equal distribution of the load over a larger area. The ground conditions and the foundation depth required determine the choice of method to be applied.
