Types Of Piling Rigs Available And Their Use In Shell & Core
Every basement project is as unique as the person who designed it and different types of ground, building and available space all require an equally unique type of building technique to get the job done properly. Because of this, there are numerous different piling methods available but, knowing which is best can be a challenge. To help offer some insight on which piles might be best for your basement project, the experts at Knowles have compiled this useful guide on the most common piling methods.
Open Bore Piling
This type of piling is pretty universal and can be used on both bigger and smaller sites, with varying types of ground substrate. Something called a ‘rotating auger’ is used to remove soil down to the chosen depth, after which steel cages and concrete are used to fill the holes. This method causes little vibration making it preferable when building retrofit basements for terraced properties, which is useful for London.
CFA piling is the quietest method of piling, making it one of the more popular kinds within a local community. It involves taking the auger out of the pile bore very slowly whilst pumping cement through the auger stem into the pile, bit by bit.
Retaining walls are essential in every basement construction, to hold up the sides of the hole whilst excavating and keep the soil from falling back in.
Contiguous Bored Pile Walls
This type of retaining wall is mostly used to hold soil back while excavations go ahead. The type of soil on the property will determine how large the gaps between the adjacent piles are, making them a valuable tool for basement projects where each aspect is different.
Secant Bored Pile Wall
Secant piles are similar to contiguous pile walls and are also used as retaining walls in basement construction. The difference is that secant piles use an innovative interlocking system of shafts which tends to look more attractive onsite and also works better where ground conditions are less than optimum, or the area has a high water table.
Cased piles are a simple and economical way of driving piles due to the fact that they can easily be cut or lengthened, and parts are easy to come by. Often used in soft ground, the piles are driven in with an internal drop hammer in order to reach a suitable depth.
Mini Piling & Restricted
Often called ‘micro piling’, mini piles are used for basement underpinning. They are particularly useful in restricted spaces where the width and height of a building means that equipment needs to be compact (like under a house for a retrofit basement). They can be installed using many different methods including: rotary, drilling, jacking and impact driving, making them a popular choice for many basement construction companies.
Knowles’ has over 20 years of experience in the highly specialised field of basement construction, including all types of piling. If you currently require a consultation for an upcoming basement project, get in touch with one of our experts.