Our company provides services for driving reinforced concrete (RC) piles and installing a pile field. We accept applications from companies and individuals. Guarantee High Quality works, low prices. Designing a pile field has the main task of calculating the maximum design load on each pile and the optimal standard size of piles and grillages before starting excavation work. Reinforced concrete piles should be driven in after laying out the pile field in an open pit.
Preparing the pile field
Pile field marking
Information useful for you:Stages of marking a pile field
- Drawing up a plan determining the exact size of the piles and the distance between them.
- Determination of geometric parameters - determination of diagonals and right angles between piles.
- Installation of marking pegs.
- Pulling the cord and setting corner marks for the piles.
- Work begins with corner piles.
Carrying out all necessary work accompanied by special control of the accuracy of the geometry of structures and buildings using geodetic surveying.
Basic principles for calculating the number of piles
To ensure the accuracy of the foundation arrangement, it is necessary to determine the number and size of piles. The choice of pile length depends on the type of soil on which construction is planned. The number of piles is calculated taking into account the size and weight of the future building. To do this you need to have the following data:- Plan of the first floor of the house.
- Calculation of the number of piles for each internal side of the building. The distance between piles should not exceed 2 - 3 meters.
- Marking the corner points for driving piles will make it possible to determine the external corners of the building.
- The calculation of the foundations of pile foundations is made based on the strength of the pile material, the bearing capacity of the foundation foundations and the characteristics of the soil.
- Calculation of pile structures is carried out depending on the planned loads that the foundation will receive from the constructed building.
The cost of a pile field
It is easy to calculate the cost of constructing a pile field using customer data on the number of piles and their length. The company's website has a convenient section, an electronic calculator. Using the necessary data, you can independently calculate the cost of installing a pile field in each specific case. For example, if you need to drive 45 piles, each 15 m long, it is easy to calculate that the cost of such work will be 202,500 rubles.total cost work when concluding a contract for work performed consists of a number of parameters, such as:
- Distance to the construction site.
- Features of the soil at the work site.
- The total amount of work that needs to be completed.
Prices are calculated using a calculator, depending on the size, design features. The application can be submitted online.
Reasons to contact our company
- The company has many years of experience installing pilings in a wide variety of construction conditions.
- Qualified personnel work quickly and efficiently.
- We will fulfill orders in any volume.
- We work with both large construction organizations and private developers.
- Flexible pricing policy.
Contact us and we will do the work
Our company is engaged in the supply and driving of piles, both reinforced concrete and screw. We will produce piles foundation work. We work in the Moscow region.
Modern housing construction of various scales and directions (industrial, civil, commercial) has a large selection of technologies used at various stages of construction. The choice of the optimal option is carried out by designers and property owners at the development stage project documentation. One of the most popular ways of arranging a foundation is laying a pile field.
Pile field - what is it and why is it needed?
A pile field is the basis of a pile foundation of any type (screw, reinforced concrete, cast-in-place). When constructing the foundation, it is necessary to strictly follow the attached diagrams, since correct laying of the pile field ensures the reliability of the entire structure and its durability.
Generally speaking: specially prepared piles are installed at points on the development site, which are subsequently tied with grillages. The resulting foundation is a pile foundation. The grillage is a mandatory element for a pile foundation. It performs a connecting function between all supports and guarantees uniform load distribution between the piles. The created monolithic structure has excellent performance characteristics for any type of structure.
The pile field transfers the building load to the ground. The depth of piles is set in the project and depends on many factors:
- Type and characteristics of soils.
- Groundwater depths.
- Total weight of the structure and many others. etc.
Thus, builders come to dense soil and the piles transfer stress to them. The construction of a building or structure is permissible only after proper laying of piles, tying them with a grillage and waiting for the established period of hardening and compaction.
Calculation of the number of piles
Before proceeding with the installation of piles, it is necessary to perform a number of preliminary works. The first stage is the calculation of the pile field.
This procedure provides a detailed and mathematically based analysis of the distribution of supports on a construction site. It is produced in several stages:
- The designer determines the total load that the erected structure will create on the foundation.
- The bearing capacity of 1 pile laid in the foundation is calculated.
- The total load is divided by the characteristics of one support and thus the number of piles required for a particular object is determined.
When determining the total load arising after the construction of a building or structure, the characteristics of all building materials, future use of the structure and the total area of the building, as well as individual structural elements.
The GOST standards developed by design institutes and approved contain calculated load indicators for the operation of each type of building. They are determined taking into account practical experience. For residential buildings - approximately 150 kg/m2; for industrial construction - 200 kg/m2.
Specific gravity 1 m 2 walls
When constructing several floors, it is important to take into account the number of floors and make calculations both for each floor separately and for the entire structure as a whole.
Specific gravity of 1 m 2 floors
Specific gravity of 1 m 2 of roofing
When making calculations, it is necessary to take into account the region where construction takes place. Each region has unique snowpack averages. When developing a project for a pile field, it is necessary to calculate the loads from the pressure of the snow cover, based on average statistical observations for a specific area.
The average snow cover weight is given in the table:
To obtain the specified data, it is necessary to multiply the roof area of the building by the mass of the snow cover. 20% is added to the final result - this is an additional parameter called the reliability coefficient.
Design of a pile field requires special attention to calculations. It is necessary to achieve the optimal combination of the number of supports, their strength and depth. For these works, it is important to have accurate data from geological and geodetic pre-design tests.
As an example, the table below contains indicators of the bearing capacity of soils and screw piles:
|
Soil type |
Design soil resistance *, kg/cm2 |
Load-bearing capacity of a screw pile, kg | ||||
| VSG-1 73/250 | VSG-1 89/300 | |||||
| dense | Wed tight | tight | Wed tight | tight | Wed tight | |
| Coarse gravelly sand | 13.0 | 12.0 | 6378 | 5888 | 9185 | 8478 |
| Medium sand | 12.0 | 11.0 | 5888 | 5397 | 8478 | 7772 |
| Fine low-moisture sand | 5.0 | 4.0 | 2453 | 1963 | 3533 | 2826 |
| Fine sand saturated with moisture | 3.0 | 2.0 | 1472 | 981 | 2120 | 1413 |
| Dry sandy loam | 5.0 | 4.0 | 2453 | 1963 | 3533 | 2826 |
| Sandy loam saturated with moisture | 3.0 | 2.0 | 1472 | 981 | 2120 | 1413 |
| Dry loams | 4.0 | 3.0 | 1963 | 1472 | 2826 | 2120 |
| Loams saturated with moisture | 3.0 | 1.0 | 1472 | 491 | 2120 | 707 |
| Dry clays | 6.0 | 2.5 | 2944 | 1227 | 4239 | 1766 |
| Clays saturated with moisture | 4.0 | 1.0 | 1963 | 491 | 2826 | 707 |
And in the end, after receiving all the calculated data, they move on to determining the number of supports for a specific project. To do this, the total mass is divided by the load-bearing capacity of one pile (as mentioned above).
Pile field marking
The pile field diagram serves as the basis for outlining the project. These works are carried out by qualified surveyors.
The drawing determines the position of the entire structure and each pile separately on the building site. A geodesist engineer, using special equipment (electronic total station, GPS systems), determines their actual location on the site and secures them with reinforcement with an accuracy of 1 cm. Depending on the complexity of the structure and accuracy requirements, this work can also be performed with a tape measure.
The procedure for setting out (laying out) a pile field includes several stages:
- Bringing field baselines to the construction site.
- Breakdown of the location of each pile on the site.
- Determination of the zero level of the pile field (the mark at which the supports should reach after they are laid).
It is important to securely secure each point and ensure their safety. Otherwise, you will have to call specialists again.
For convenience, it is recommended to use the following method: secure the foundation axes to cast-offs behind the building site. Then a string is pulled between them - the intersection point of the two threads is where the pile is installed. This way you will ensure their safety when moving people and equipment around the site.
Be sure to use the approved pile field plan - this way you avoid violations and guarantee the legality of the work performed.
Installation of a pile field
After completing all the design work and subsequent securing the points of the pile field on the site, you can proceed to installation.
In practice, piles are arranged in the form of several figures:
- Pile bush - a small number of piles located nearby. The grillage in this case can have an aspect ratio of 1:5. The best option for high structures, columns.
- Pile strip - supports are arranged in a row. Suitable for elongated walls.
- Pile field is a large number of piles evenly distributed on the site. For residential and industrial buildings.
Before work, all necessary equipment must be delivered to the site. It is imperative to have at your disposal a sufficient number of piles with the required characteristics. Before laying the supports, a vertical layout of the building site is carried out.
If the piles you have chosen are screw ones, then you can “screw them in” on your own using special devices for such work.
For diving reinforced concrete piles a coping machine is used. In this case, the work includes the following steps:
- The machine is installed in the place where the pile is being beaten, and the pile is dragged to it.
- After slinging the pile, it is brought to a vertical position. Maintaining verticality ensures the strength of the structure and reduces the risk of destruction of the pile and the operation of the pile driver.
- After docking with the piling hammer, the pile begins to be driven into the ground to the required depth. The design specifies the estimated failure of the pile - the depth at which it stops going into the ground.
- After driving all the supports, they are leveled to the established height. Most often this is done by workers using jackhammers.
When laying each pile field, a drawing must be developed. This document serves as a kind of instruction for carrying out the entire complex of work. Following these calculations guarantees that the entire structure will achieve the designed parameters. Therefore, it is especially important to correctly install the pile field.
The main element in building a house is a properly executed foundation. Which to choose? This depends, first of all, on the type of soil on which they plan to build the house. If the site is dominated by soils with low bearing capacity and high susceptibility to deformation, then pile foundations are used. When arranging such a foundation, the most important element is the pile field.
Pile field - what is it?
Pile foundations have been widely used for many years in various fields of construction. This is today one of the most popular methods of deep foundation laying in weak soils. There are several types of piles, which differ from each other not only in shape, but also in manufacturing technology. However, all foundations made with their use have something in common - a pile field. The piles, installed in the places provided for by the project, are connected to each other by a grillage, creating a monolithic structure that evenly transfers the load to the ground.
The location of the piles must be developed in the project. They are always at the corners of the building, under the joints of load-bearing walls and at certain intervals along the walls of the building. Their length and pitch depend on the depth at which the load-bearing soil layer is located.
Placement methods
Depending on the building design and design requirements (soil type, design load), a drawing is drawn up according to which the piles are placed. There are several placement methods:
- pile bush - piles are arranged in a group, forming one structure, used as a base for columns, racks, supports;
- strip - where they are located in a row, under structures of considerable length;
- pile field – a compactly located large number of piles for making foundations for buildings of a large area.
These methods can be used either individually or in combination, depending on the building design. The total number of piles that are placed under a structure can also be called a pile field.
Calculation of the number of piles
Before proceeding with the installation of the foundation, it is necessary to make some calculations and draw up a plan for the pile field. Such work should be performed by a specialist, since even if you know several calculation formulas and have tables, it is difficult to learn how to do it yourself. The soil is preliminarily assessed, this is done by a surveyor, after conducting a series of studies, he determines:
- the strength of soil resistance and its density, as well as the types of soil on the site;
- the depth to which the soil freezes, soil moisture and the depth of the groundwater table.
Based on the data obtained, the depth to which the piles will be laid is calculated, the places for their immersion are determined, and the pile field is marked according to the diagram.
Then the load on the base is calculated, the load-bearing capacity of one pile is determined and, dividing the first value by the second, the required number of piles is obtained. The operating load on industrial buildings is 200 kg/m. sq. floors, in civil engineering this value is 150 kg/sq.m. respectively.
Operational loads calculated when designing and constructing a pile field for a building, for example, 2 floors, are made taking into account both floors.
After this, the pile field is marked directly on the site.
Pile field marking
The working drawing is a guide for staking out the structure. To make the breakdown easier, it is best to use a cast-off. Outside the proposed building, cast-off poles are installed, and wires are pulled between them in accordance with the axes of the building, defining the base lines of the building. Then, also using wire or cord, the locations of the piles are determined. The intersections of the lines formed by the wire must coincide with the axes of the piles and correspond to the previously drawn up drawing/scheme.
The cast-off posts are installed rigidly to prevent their possible displacement during operation. Boards (20 - 40 mm thick) are nailed to the posts, on which the wire/cord is secured with nails.
Let's learn how to properly mark the terrain by watching the video:
What exactly are piles? Selection and installation
Piles, as structural elements, are used to transfer loads to the ground. The load is transmitted through the lower end (vertically) or by friction, through the side surface (horizontally), or a combination of these.
The most popular types of piles used in construction
There are many types of piles used in construction, which differ in geometry, materials and execution technology.
- Ready-made piles are a pre-prepared product made of reinforced concrete, metal, plastic, wood. They are introduced into the ground using various methods (driving, vibration, pressing, screwing or a combination thereof).
- Piles made in the ground are usually reinforced concrete or concrete. They are performed in a well drilled using a casing pipe or a hollow auger. A concrete mixture is fed into the well, which, when hardened, forms the body of the pile.
Installation methods and the material used, as a rule, are determined by the type of soil, terrain, and the required arrangement of piles.
Installation
After the pile field has been marked, it is time to work on its construction. Access roads should be prepared, the necessary equipment should be brought to the construction site, and the required number of supports should be prepared.
Most often, reinforced concrete piles with a cross section of 30x30 cm and 40x40 cm are used. Their bases can be pointed or blunt. Common lengths range from 4 to 15 meters. Length is limited by transport capabilities. If it is necessary to use longer piles, prefabricated elements with mechanical connectors at the ends are used. Driving piles is carried out using pile drivers, most often hydraulic ones. The machine is installed in the desired location, after which further operations are performed: bringing the pile to the vertical, installing it at the driving point and subsequent immersion into the ground.
Advantages of reinforced concrete piles:
- relatively small amount of equipment on the construction site;
- “clean” construction site without land, independence from weather conditions;
- execution speed, 200-350 m of piles (total length) per day using one pile driver;
- the use of high-quality concrete (C40/50) ensures good elasticity of the pile, high driving efficiency, strength and resistance to cracks;
- high-quality concrete provides the necessary tightness and frost resistance, as well as resistance to aggressive influence water;
- possibility of inclined installation, at a large angle;
- You can continue working and load the piles directly after driving them into the ground.
The disadvantages include:
- vibration and noise that occurs during driving;
- the need to monitor objects in the neighborhood that are sensitive to vibration.
If the construction site has good access roads and enough space to install the necessary equipment, then the use of reinforced concrete piles is the most preferable option.
Due to the extremely fast installation time and the possibility of immediate loading, screw piles are successfully used on construction sites where the principle of time is money. They are used to strengthen the foundations of buildings, to install masts, communication towers, lighting poles, light structures, and fences.
Advantages of screw piles:
- quick installation - can be completed in one day;
- the ability to perform work without the use of special equipment (if the soil allows);
- maintaining cleanliness at the construction site, absence of contamination with concrete mixture; no need to extract and dispose of soil;
- the ability to perform work on site immediately after installation;
- low noise level and lack of vibration;
- ease of dismantling in case of construction of temporary structures;
- possibility of quick and weather-independent installation;
- ease of connection with other steel elements;
- Possibility of manufacturing in difficult field conditions;
- independence from concrete supplies.
However, screw piles also have certain disadvantages:
- if the construction site is located on rocky terrain, the use of special equipment is necessary; manual installation will be impossible;
- installation difficulties in hard soils, it all depends on the power of the machine and the structural features of the pile;
- the metal is susceptible to corrosion, so additional protection is required.
Installation of screw piles can be done either using special machines or manually. You can use special tools or ask two friends for help. Three people are enough to do this work on a medium-sized area. The work is carried out in accordance with the drawing according to the completed markings. The pile is placed in the intended location. Then a lever is inserted into the technological hole, with the help of which it is gradually screwed into the soil. In one revolution it plunges 190 mm. As a lever, you can use a thick-walled pipe, three centimeters thick, or a long crowbar. When screwing in, you should take your time and constantly check the verticality of the screw.
The screw-in lever must have 2.5 m in each direction. If the pile is long, the lever can be increased using available materials. The main thing is that the lever arms are the same.
Regardless of what material is used to make the pile field, it is important to remember that the preparatory work is thorough. It is advisable to entrust geodetic work to a qualified specialist, and to lay out the site without rushing, carefully checking the drawing.
We make the casting in such a way that the bottom board is the level to which we will place all the pillars, and the second top level grillage We align both boards of all castoffs at “0” horizontally relative to each other. That is, the bottom board for the posts of one cast-off should be on the same level as the bottom board of the other cast-offs. The same goes for the top boards for the grillage.
Marking a columnar (pile) foundation
We stretch the strings so that their intersections are the centers of the pillars (wells). We find angles of 90⁰ for a rectangular foundation using the Pythagorean method by constructing a triangle with dimensions 3x4x5m. Read how to do this in the article: Rules for constructing a rectangular foundation. The distance between the strings is equal to the distance between the pillars according to the project. The distance from the cast-offs to the foundation contour is 3 meters.
At the intersection of the strings we lower a plumb line, which will show us the centers for drilling holes under the pillars.
We insert pegs at the plumb points. And we temporarily remove the strings so that they do not interfere with us while drilling wells.
We drill holes for pillars.
The next step is to pull the removed strings to bring all the pillars to a common level. This method has several features. Since the strings by which we found the centers of the pillars (wells) will interfere with us during the formation of the pile, we will no longer need such a marking arrangement. We will need to move the strings by a distance equal to the radius of the pillar (using a tape measure), that is, the strings will already pass next to the pillar, and will serve as a guideline for the general level of the piles. How to do this, see the figure.
We bring the pillars to the general level according to the markings. The level, we remind you, is displayed at “0”.
Grillage marking
The next operation is marking the grillage. For this purpose, we will use the old markings for the centers of the piles.
And so, we have a self-tapping screw along which strings were pulled to find the centers of the piles.
From this self-tapping screw, using a plumb line, we make a mark on the top cast-off board, intended for the level to which we will place our grillage.
From the mark in different directions we mark the same distance, equal in total to the width of the grillage. In our example, we will make a grillage 40 cm wide, therefore, we measure 20 cm in different directions and screw in the screws. That is, we will get 2 self-tapping screws for the outer and inner contour of the grillage.
We make markings for the grillage. We stretch the twine onto the screws of the top cast-off board.
We bring out the grillage along the strings.
What is important to know when marking pillars and grillage using the method described in this article.
Task. It is necessary to build a grillage measuring 6x8m and 40cm wide. It is necessary to calculate the dimensions of the rectangle for the piles.
Solution. For this grillage, we will need to build a marking in the form of a rectangle with dimensions of 6 by 8 meters, which will be the outer contour of the grillage.
In our example for the pillars, we string strings that will run through the center of the piles. The piles, in turn, should pass exactly in the center of the grillage. Therefore, to build a rectangle for the piles, we need to retreat from the sides of the 6x8m rectangle by an amount equal to half the width of the grillage, that is, in our case, 20 cm from each edge. As a result, the rectangle built for the pillars will measure 5.6 m by 7.6 m.
Let's see how it will look in the picture.
From the author
In this article we looked at one of the markup methods columnar foundation. There can be many options for marking. The main thing is to observe the dimensions, level and right angles.
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Naturally, before starting installation pile-screw foundation, the future pile field should be marked. This work requires maximum attention, since the slightest deviation from the norm can subsequently cause serious deformations in the foundation structure.
To carry out this work, you will need reinforcement bars and a long rope (preferably twine).
For clarity, we will consider the marking of a pile field using the example of a rectangle or square, since these geometric shapes are the most popular in terms of foundation design.
Naturally, before starting to mark out the pile-screw field, a geological study of the soil was carried out on the site, on the basis of which a decision was made in favor of purchasing a certain number of piles of one type or another.
First you need to install the reinforcement bars in the corners to make it easier to work later. A rope should be stretched between the reinforcements, and it should be tightly stretched, without sagging. We do not recommend touching the rods in order for the marking process to be successful.
Keep in mind that if you have a fence, then when creating markings, you should take into account the parallelism of the lines.
The point of marking the field is that the screw piles will be installed at the intersections of the twine, which means that the reinforcement bars to which the ropes will be tied should be located slightly outside the future foundation so that they do not interfere with the process of installing the piles, because marking is not allowed dismantle until the process is completed.
To make sure you get an even rectangle or square, measure both diagonals, they should be equal. If you are convinced, then get ready for the next stage - drilling holes.
You will need a drill whose diameter will not exceed the diameter of the screw piles, otherwise you cannot avoid the fact that the piles will become loose, that is, there will be no stability. Also, the depth of the holes must be made less than the distance to which the piles are supposed to be screwed into the ground.
This stage is not mandatory, but it is better to listen to the advice of professionals, and now we will explain why. Firstly, by giving the pile a certain direction, it can be installed faster while maintaining the level. Secondly, you may encounter an insurmountable obstacle on the way; accordingly, based on this data, you can adjust the markings. Drilling holes for screw piles helps builders save time and effort.
If you decide to install a pile-screw foundation yourself, then please treat the stage of marking the pile field as responsibly and carefully as possible.