Online calculator for calculating bored pile-grillage and columnar foundations

Information on the purpose of the calculator

Online calculator for monolithic bored pile and columnar grillage foundation is designed to calculate the dimensions, formwork, the number and diameter of reinforcement and the volume of concrete required for arranging this type of foundation. To determine the appropriate type, be sure to contact the experts.

Pile or column foundation - a type of foundation in which piles or columns are located directly in the ground itself, at the required depth, and their tops are interconnected by a monolithic reinforced concrete tape (grillage), located at a certain distance from the ground. The main difference between the columnar and pile foundation is the different depth of installation of the supports.

The main conditions for choosing such a foundation are the presence of weak, vegetative and heaving soils, as well as a large freezing depth. In the latter case, and with the possibility of driving piles in all weather conditions, this type is very relevant in areas with a harsh climate. Also, the main advantages include the high speed of construction and the minimum amount of excavation, since it is enough to drill the required number of holes, or drive in ready-made piles using special equipment.

There are many variations of this type of foundation, such as the geometric shape of piles, materials for their manufacture, the mechanism of action on the ground, installation methods and types of grillage. In each individual case, it is necessary to choose your own option, taking into account the characteristics of the soil, design loads, climatic and other conditions. To do this, you need to contact specialists who can make all the necessary measurements and calculations. Attempts to save and self-build can lead to the destruction of the building.

The following is a complete list of the calculations performed, with a brief description of each item.

General information on the results of calculations

• Total grillage length
- The perimeter of the foundation, taking into account the length of the internal partitions.
• Sole area of grillage
- Corresponds to the dimensions of the required waterproofing.
• The area of the outer side surface of the grillage
- Corresponds to the area of the required insulation for the outer side of the foundation.
• Total volume of concrete for grillage and pillars
- The volume of concrete required to pour the entire foundation with the given parameters. Since the volume of ordered concrete may differ slightly from the actual one, as well as due to compaction during pouring, it is necessary to order with a 10% margin.
• Concrete weight
- The approximate weight of concrete is indicated by average density.
• Load on the soil from the foundation at the base of the pillars
- The load on the soil from the weight of the foundation at the base of the pillars / piles.
• Minimum diameter of longitudinal rebars
- The minimum diameter, taking into account the relative content of reinforcement from the sectional area of the tape.
• Minimum number of rows of grillage reinforcement in the upper and lower chords
- The minimum number of rows of longitudinal rods in each belt, to prevent deformation of the tape under the action of compressive and tensile forces.
• Minimum diameter of transverse reinforcement bars (stirrups)
- The minimum diameter of the transverse and vertical reinforcement bars (stirrups).
• Minimum number of vertical rebars for poles
- Number of vertical rebars per post/pile.
• Minimum pole reinforcement diameter
- Minimum diameter of vertical rods for posts/piles.
• Step of transverse reinforcement bars (stirrups) for grillage
- Clamp spacing required to prevent shifts of the reinforcing cage when pouring concrete.
• Reinforcement overlap
- When fastening segments of rods with an overlap.
• Total length of reinforcement
- The length of the entire reinforcement for knitting the frame, taking into account the overlap.
• Total weight of reinforcement
- Reinforcing cage weight.
• Form board thickness
- Estimated thickness of the formwork boards in accordance with the standards, for the given foundation parameters and for the given support spacing.
• Number of formwork boards
- The amount of material for formwork of a given size.