RANNILA steel piles: scope, technical characteristics and methods of extension. Types of piles
Scope of work: 1. Docking sections of piles. 2. Joint bolting. 3. Welding of nuts and welding of a joint.
4. Anti-corrosion insulation of the joint.
Gauge: 1 joint
5-6-1 Building solid reinforced concrete square piles
Table 18 - Group 6 Norm 1
| Resource ID | Resource name | Unit | 5-6 |
| man-hour | 5,45 | ||
| Average category of work | 4,3 | ||
| Machinist labor costs | man-hour | 11,13 | |
| Machines and mechanisms | |||
| 204-0202 | Mobile welding units with a diesel engine, with a rated welding current of 250-400 A | mash-h | 1,02 |
| 205-0501 | Compressor stations, pressure 245 kPa, flow 40 m3/min | mash-h | 3,71 |
| 214-0311 | Copra universal with a pneumatic hammer weighing 8 tons | mash-h | 3,71 |
| 270-0108 | mash-h | 0,28 | |
| materials | |||
| 111-0073 | T | 0,00151 | |
| 111-1530 | T | 0,00073 | |
| 111-1848 | T | 0,00385 |
Group 7 Diving of reinforced concrete pile-shells with a diameter of up to 2 m with the extraction of soil from the cavity
Scope of work: 1. Control assembly of pile-shell sections. 2- Installing and removing the device for hanging the shell in the guide frame. 3. Installation of shell piles in the guide frame. 4. Building piles-shells with welding of flanges, nuts and anti-corrosion insulation of joints. 5. Installing on the pile-shell and removing the vibrator from it. 6. Installation and dismantling of airlifts and high-pressure pipes. 7. Immersion of pile-shells with extraction of soil from the cavity of the pile-shell.
Meter: 1 m3 reinforced concrete pile-shell
Immersion of reinforced concrete pile-shells up to 12 m long into soils with a vibrator:
5-7-1 incoherent
5-7-2 liaison
The same, over 12 m long into the ground:
5-7-3 incoherent
5-7-4 liaison
Table 19 - Group 7 Codes 1 to 4
| Resource ID | Resource name | Unit | 5-7 | 5-7 | 5-7 | 5-7 |
| Labor costs of construction workers | man-hour | 21,28 | 25,9 | 24,22 | 29,4 | |
| Average category of work | 3,8 | 3,8 | 3,8 | 3,8 | ||
| Machinist labor costs | man-hour | 11,55 | 20,17 | 13,57 | 29,2 | |
| Machines and mechanisms | ||||||
| 202-0435 | Gantry cranes for work on bridge construction, lifting capacity 65 t | mash-h | 6,76 | 10,92 | 7,31 | 12,6 |
| 204-05CH02 | Manual Arc Welding Machine [DC] | mash-h | 1,96 | 1,96 | 2,66 | 2,66 |
| 205-0201 | Mobile compressors with internal combustion engine, pressure 800 kPa, flow 10 m3/min | mash-h | 0,21 | 1,26 | 0,76 | 4,51 |
| 214-0411 | Low-frequency vibratory drivers for driving shell piles | mash-h | 3,01 | 3,84 | 3,28 | 3,89 |
| 214-0901 | Soil pumps, flow 60 m3/h, head 165 m | mash-h | 0,21 | 1,26 | 0,76 | 4,51 |
| 270-0108 | Mobile bitumen boilers, capacity 400 l | mash-h | 0,28 | 0,28 | 0,28 | 0,28 |
| materials | ||||||
| 111-0073 | Oil construction bitumen, brand BN-90/10 | T | 0,0014 | 0,0014 | 0,0014 | 0,0014 |
| 111-1129 | Hot-rolled carbon steel plate of ordinary quality with sheared edges, thickness 9-12 mm, St3sp grade steel | T | 0,01 | 0,01 | 0,01 | 0,01 |
| 111-1530 | Electrodes, diameter 6 mm, brand E42A | T | 0,0014 | 0,0014 | 0,0019 | 0,0019 |
| 111-1848 | Construction bolts with nuts and washers | T | 0,00448 | 0,00448 | 0,00448 | 0,00448 |
| 112-0293 | Wooden wedges 50x100x400 mm | m3 | 0,002 | 0,002 | 0,002 | 0,002 |
| By project | Piles-shells reinforced concrete | m3 | 1,01 | 1,01 | 1,01 | 1,01 |
| By project | Suspended scaffold structures | T | 0,0378 | 0,0378 | 0,0378 | 0,0378 |
The pile-screw foundation is one of the best in the construction of not very heavy buildings, great for. To understand all the pros and cons of this type of foundation, let's deal with it in more detail.
Screw piles have stood the test of time
Filling piles with concrete
After leveling, a concrete mixture is poured inside the piles, which is designed to protect x from corrosion from the inside.
Installing a grillage on a pile-screw foundation
At the final stage, they mount, i.e. the very foundation for the future home. For lighter construction, for example, a house made of timber or logs, it is possible to install a grillage from a thick timber. For houses made of bricks or blocks, it is better to make the grillage reinforced concrete.
The pile-screw foundation does not require time for shrinkage, you can continue immediately after installing the grillage. Now you can start installing the frame of your house. The foundation is ready for loading and full operation.
Where to buy piles and what is the price?
Unlike conventional piles used to create pile foundations, shell piles are hollow rods of considerable diameter. Such structures have found application in the construction of large structures, for example, for laying multi-storey buildings.
Very often they are used on unstable and weak soils, since they have a sufficient area of \u200b\u200bcontact between their walls and soil layers.
Shell piles are also used in places that are regularly subjected to oscillatory processes. In particular, they are used to create supports for bridges and highways. Piles fully justify their purpose in conditions of exposure to moisture, as well as in geologically hazardous areas.
What are shell piles?
The bulk of the shell piles is made of concrete and reinforced with a reinforcing cage. Such reinforced concrete piles-shells can be built up to a length of 48 m. They can have cone-shaped tips, or they can do without them. The high reliability of reinforced concrete allows the operation of these products for a very long time.
Unlike them, metal piles-shells are, in essence, pipes of various sections. A little less often, other forms of profiles created by welding are used.
Shell pile driving
To immerse shell piles in the ground, a special vibration technique is used. Behind 
due to the generated vibration, the products are gradually sunk into the soil to a predetermined depth. Vibration contributes to loosening the soil, which allows the pile to move deep into the earth.
There is a difference in shell immersion methods. Diving can be done with or without excavation. In the first case, a drilling rig is required. In the second case, no earthworks are carried out at all.
Procedure at the construction site
If we consider the procedure for performing operations for deepening our product into the ground, then we can list the main stages of such work:
- Preparation of the soil for work, that is, cleaning and marking the site.
- Transportation of submersible rods. Since the rods have a solid weight and impressive dimensions, special equipment is used for their transportation, such as tractors, cranes, unloading equipment and heavy platforms.
- Installation of the unit that will deepen the piles. Installation of the guide device.
- According to the existing markup, the products are buried in the soil. Each pile shell must be installed strictly in its calculated place. Immersion is carried out by means of vibration created by the unit with a certain amplitude.
- The piles are driven to the required depth. If it is planned to remove the shell from the ground, then this operation is performed using a special device mounted on a crane.
In this sequence, all the rods are deepened. Since vibration adversely affects the buildings surrounding the construction site, the use of this method should be agreed with the relevant authorities.
How are shell piles built up?
A single shell pile usually has a length of up to 12 m. Therefore, it is not uncommon for piles to be built up to reach the required size. Such an extension can be performed in two ways, each of which is successfully applied in practice.
Let's consider both methods:
- The pile is built up as one of its parts sinks to a certain depth. After building up the first part, the second pile is deepened in the same way. This happens as many times as needed. The most popular way to connect two shell piles is a flange connection. At the ends of neighboring piles, metal flanges are fastened with holes for bolted connection. This type of fastening is quite reliable and fast. In addition, a high accuracy of matching the axes of the two piles is ensured.
- The pile-shell is built up in advance, before the start of the dive. The specified depth is calculated, and then, according to the required dimensions, a monolithic structure is made. Between themselves, separate sections of the structure are connected by a welded seam. Since the work requires precision, it is produced on special stands. All welding joints must be securely insulated. This is usually ensured by lubricating such places with bitumen or polymer mastic. This method is less expensive in terms of material consumption.
We found out what shell piles are, what they serve for, where they are used, how they are buried in the ground, piles are built up during deepening and the sections of piles are connected to each other during the production process.
- RANNILA steel piles
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The tubular metal pile RR is made of a steel pipe with a longitudinal seam produced by the Finnish steel plant Rautaruukki. The mechanically expanded pile has the widest range of applications and does not require heavy driving equipment. RR piles, which are characterized by low material consumption, have been type approved by the Finnish Ministry of the Environment. |
Pneumatic rammers can conveniently drive RR piles even in tight and inaccessible places. |
equipment, when laying foundations for hangars, individual houses, cottages, detached houses, etc.
Specifications
The technical characteristics of the piles are shown in the table below.
DIMENSIONS AND TECHNICAL CHARACTERISTICS OF PILES RR
|
Diameter |
Thickness |
Weight, |
Overlay type / extension method |
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|
Fixed |
Mobile |
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Extension method
RR piles are built up with pads, which are adjacent to the pile shaft by friction. Connection by welding is not used on the construction site, with the exception of piles of the largest sizes. The type approvals of the Ministry of the Environment (4/6121/96 and 159/5331/93) also cover RR pile extensions. A record of type approval is applied to each individual pile element at the place of build-up. Lining
Protective pads RR are placed under the lower heads of the piles, which are produced in 2 types: for soil and rocky soil.
headband
An RR cap is installed on the upper head of the pile, which is attached to the pile shaft with bushings. The connection of a pile with a structure superimposed on it is calculated as a hinge, however, with a pile height of up to 3 m, a rigid connection is used between it and the supported structure, when possible.
Headband dimensions RR
Corrosion
The corrosion of the steel pile must be taken into account when calculating the loads. The tolerance for corrosion is taken depending on the rate of corrosion of the pile and the design service life of the supported structure.
The corrosion rate in mineral-bearing soils is on average below 0.02 mm/g, i.e., 1 mm in 50 years.
Load bearing capacity
The maximum allowable load on the pile RR is set at the lowest of the following indicators:
- The maximum allowable central
structural compressive load
- @SHIARICK = maximum allowable per-
buckling load
- Geotechnical bearing capacity
The maximum allowable central structural compressive load (collapse) of an RR pile is 33-58% of the lower yield point of the pile steel (Pile driving instructions LPO-87 of the Geotechnical Society of Finland, paragraph 3.4231).
Longitudinal bend
When driving into soft soils, buckling must be taken into account as a factor that can affect the bearing capacity of the pile. The table below shows the maximum buckling loads for RR piles.
The strength of the soils surrounding the pile can be determined, for example, by a paddle shear test. The radius of the initial rounding must be checked on the finished pile, for example, using a flashlight.
|
Radius of initial rounding, m |
Maximum allowable pile load, kN Shear strength of undrained soil, kN/m2 |
|||||
Maximum allowable buckling load of piles RR with a corrosion tolerance of 1 mm
Geotechnical bearing capacity
The geotechnical bearing capacity of the RR pile is ensured by driving the pile into the ground until the specified driving resistance is reached. Steel piles serve as a rule for support, and at the same time, the geotechnical bearing capacity is equal to the bearing capacity of the lower head. Sufficient geotechnical bearing capacity can be achieved, for example, by using a falling woman, a pneumatic rammer, etc. equipment. If the impact force of the driving equipment is not known, the equipment must be calibrated, for example, by measuring shock waves (shock shocks).
Engineering and geological surveys
For the design of driving, it is necessary to know the depth of piling, in the case of soft soils, the shear strength of undrained soil. For more detailed design instructions, please refer to the Ministry of the Environment approved instructions available from the RR Piling Factory and Dealers.
- Registration: 13.06.12 Messages: 7 Acknowledgments: 2
How to increase driven piles?
- Registration: 13.06.12 Messages: 7 Acknowledgments: 2
- Registration: 01/14/13 Messages: 239 Acknowledgments: 45
The tension of the reinforcement can be carried out by pulling it out by concrete pressure on the clamping head during its forced compression (pressing), or by using cement that expands during hardening, or, finally, by automatically pulling the reinforcement with the centrifugal method of manufacturing reinforced concrete pipes.
A typical example of the manufacture of reinforced concrete elements from stressed concrete with reinforcement tensioned by concrete pressure is the production of tubular reinforced concrete piles at the installation site to strengthen the foundations of a building located on the seashore.
The building was built on unstable ground and was in danger of slipping into the sea. Good solid ground was at a depth of 20 m. It was necessary to transfer the load from the building to this layer of soil, and the possibility of driving piles was excluded for fear of increasing the rate of settlement of the building due to ground vibration and, thus, causing a catastrophe. It was necessary to piles to press jacks into the ground and work under the existing building.
Reinforced concrete cylindrical tubular piles were made on site from stressed concrete of high and quickly acquired strength. The piles had an outer diameter of 60 cm and an inner diameter of 37 cm. The reinforcement consisted of eight vertical rods with a diameter of 8 mm and a spiral cage made of steel with a diameter of 6 mm. The total weight of the reinforcement was 10 kg per 1 running meter of the pile.
Between the existing foundations under the columns of the building, a reinforced concrete grillage was arranged, connecting all the soles of the foundations. With the help of special devices, the pressure from the jacks was transferred to this grillage and to the pile head.
Form for gradual increase The tubular pile consisted of an outer metal cylinder 7, composed of separate sections of half-rings 40 cm high, fastened together by clips 2 with screw clamps, and an inner steel pipe 3 with a rubber sheath 4 attached to it, reinforced with fabric.
The space between two metal cylinders was fixed from above by a movable flange 5 with holes for passing vertical reinforcement rods. At the lower end, the inner steel pipe was connected to another smaller steel pipe, also provided with a rubber sheath 7. Reinforcing bars 8 passing through the movable flange were captured by clamps 9 resting on the flange.
The process of building a tubular pile is performed in the following order. After manufacturing a part of the pile and keeping it for the required time to acquire proper strength, it is pressed into the ground with jacks and, as it deepens, the mounting clamps of the outer rings are unclenched, except for the clamps of the uppermost ring. The inner steel pipe is lifted up to the height of the area to be concreted. The spiral reinforcement is connected to the vertical one, the rings of the outer cylinder are put in place, the vertical reinforcement bars are fixed with clamps with screws, and the rods are somewhat tensioned with them.