Pile foundation: distance between piles (maximum and minimum)

The technology of foundation construction on the basis of pile construction is considered one of the most reliable and practical. It can be attributed to universal, because the flexibility of the system and the variety of approaches to the technical implementation of the framework meet the requirements of a wide range of buildings. Among them, residential buildings, industrial buildings, communication facilities and other facilities. However, in order to achieve the reliability of the pile structure, it is necessary to accurately determine the bookmark parameters. In the list of the most important of them, experts note the distance between the foundation piles, which can vary depending on a number of building characteristics and construction conditions.

What is the structure of the pile foundation?

The pile structure can be represented as a set of bearing elements and grillage. The support elements may differ in material and method of installation. For example, today the practice of driving and screw piles is practiced. In order to determine the distance between piles in the pile foundation, it is necessary to take into account the permissible depth of occurrence, the material of manufacture and other parameters of the bearing products - this is how the number of elements and the step between them are calculated. No less important is the grill function, which provides a bunch of stand-alone supports. It can be implemented in different types and designs, but, as a rule, the device of this component entirely depends on the technique of introducing and strengthening piles.

General principles of calculation

Usually engineers are guided by the account of properties of a ground and prospective weight of the future structure - in aggregate these data allow to lay the optimum pile-screw base. The distance between piles can be calculated in this case, based on their number. To determine how many support elements are required, you need to know the load level and overall load capacity of the structure. In particular, the pile can withstand about 2 tons, while the weight of the house can be tens of tons. Then follows the layout of the placement of piles throughout the area. In some cases, the load is uneven, so the location of the piles is not always correct from a geometric point of view.

Step between screw piles

The practice of construction in Russian conditions has established a minimum distance when laying a pile-screw foundation: it is 1.7 m on ordinary soil. At the same time, in each pair should leave a gap (not less than 0.5 m) of a single layer of soil, that is, a site on which land works have not been carried out. This measure will prevent the unwanted influence of the land base on the pile foundation.

Distance between piles in the maximum value for single-story objects is:

• For houses from a log or a beam - 3 m;
• For wireframe and prefabricated panel objects - 3 m;
• For buildings from pazogrebnevyh blocks, aerated concrete and cinder block - 2,5 m;
• For brick buildings - 2 m.

As you can see, light wooden buildings require less dense placement of piles, nevertheless, if a 2-storey building is planned, the step can be reduced.

Step between pile driving piles

The distance between the pile supporting elements assumes a universal calculation formula. The main parameter here is the diameter of the pile. It is important to divide the structures of this type into two categories: hanging and racks. In the first case, the minimum distance is the diameter, multiplied by three. The maximum involves multiplying the pile diameter by six.

Racks are located with a minimum step, the size of which is one and a half times greater than its diameter. It is noteworthy that the pile foundation, the distance between piles of which is reduced to a minimum, does not always win in reliability. The point is that the bush (frequent) method of placing the supports creates an undesirable effect in the form of an increase in the sediment. Therefore, it is recommended to always consider the possibility of translating loads to piles in a single configuration.

Deviations from the "norm"

Despite the development of uniform rules, on the basis of which a method for calculating the distance between piles is compiled, each case assumes a huge number of nuances. In this regard, engineers begin to follow the simple rule: to designate the maximum limit of the permissible number of piles and to distribute them rationally throughout the area, taking into account the loads.

Depending on the project for which the pile foundation is planned, the distance between piles may be reduced or increased. For example, if the plan provides for an internal supporting wall with overlapping loading on the sides, then there is a sense in a 30 percent reduction in the pitch between the bearing elements.

Increasing the distance is also not a gross mistake if technical precautions are to be taken. In such cases, an additional installation of foundation beams is usually required. It is difficult to say that it can justify increasing the distance, since such a correction will hardly make a pile-and-foundation foundation more reliable . The distance between piles, which increases due to savings, also does not justify itself. At least for the reason that additional strengthening will cost more than an "extra", but structurally sound number of foundation piles.

Configuration of the location of piles

In addition to the distance between the piles, the way to organize them also matters. The choice of a particular configuration depends on the actual loads. There are several options for placing the supports on the foundation site: individually, in a row, in the form of various geometric figures and in the form of a solid field on which the pile foundation is formed. The distance between piles in each case is guided by the general rules of calculation, but can be adjusted.

The most common pile tape (in-line configuration), solid piles and "cluster" dense methods of positioning carriers. The technique of installing elements in a row is used to support the walls of buildings - this is the usual way to build a foundation for residential buildings. It is recommended that the method of pile "bushes" is recommended for structures with intensive loads. The device of a continuous field is designed to support the heaviest structures and structures. Piles in this case are distributed evenly and combined with a monolithic grillage with a firm sole.