Excavating is not just digging some hole in the ground and plopping a basement in it. There is quite a bit of planning and technique that goes into it. The basements construction is very important as it is one of the main the supports for the entire home and building. Here is a compilation of a few different techniques to excavating a perfect basement.
Toppling and slipping are very common when excavating a hole for a basement. To avoid these issues make sure you are working with good soil. To know whether the soil you are excavating is good or not. You will need to do a soil sample in order to know for sure if the soil is top notch for digging a basement.
Create Protective Support Systems
To avoid sliding you will want to use retaining walls, or benching. You can also slope the sides of the hole so that they are not at an angle of a horizontal-to-vertical ratio greater than 1.5 to 1.0. It is also a good idea to create some sort of shied around the area for workers to operate inside of.
One of the safest and smartest ways to build a basement is to use the Island Method. When using this technique you will build the center of the basement first and then build sloped outer walls until they are properly braced. The outer walls will eventually be braced by the completed center and will be able to be fully constructed.
This technique is used mainly in congested, urban areas on larger commercial buildings. First the load bearing walls are constructed, next they pour the ground level floor above where the basement will go. Sometimes the whole building will be constructed before they even dig out the rest of the basement. This takes very skilled careful digging and can take a little more time to do.