For many construction sites, sheet piling fencing of the pit is vital necessary condition normal implementation of the zero-work cycle.
any type (including Larsen tongue), thereby ensuring reliable protection pit from soil shedding and landslides. Our mobile and high-traffic equipment is capable of working even in cramped conditions of dense buildings, where without the installation of sheet piling it is generally impossible to carry out work.
Why is sheet piling fencing for pits necessary?
The need to install sheet piling fencing for a pit is dictated by several factors, the key of which is safety requirements when carrying out construction work below zero level soil.Active building codes determine the maximum possible depth of pits and trenches in which you can work without additional strengthening of the walls:
- In conditions of sandy soil that does not have rigid structural connections, the depth of the pit without sheet piling should not exceed 1 m;
- Excavation pits in sandy loam - up to 1.25 m;
- pits in clay soil and loams - 1.5 m;
- Excavation pits in high-density soils - 2 m.
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Important: the use of sheet piling is especially important when developing pits with inclined walls, since the likelihood of soil shedding on slopes is maximum.
It is also rational to use sheet piling walls as an alternative to water-reducing works, since the construction of a fence made of steel sheet piles is subject to reuse, is a more effective and cost-effective method.
A closed sheet pile wall is a completely sealed structure - the fence does not allow water to enter the pit, thereby preventing it from flooding.
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Features of creating sheet piling
Sheet piling work is one of the most important construction processes, so it should only be carried out by professionals. Strengthening a pit with sheet piles requires a strict sequence of actions and the use of special equipment and machinery. Soil compaction will be reliable only if all technologies are followed - this is a necessary condition for the integrity and reliability of the building. If necessary, the trench can be secured with tongue and groove on a temporary basis.
Rice : Fencing the construction site with sheet piling
When choosing a technology and type of pit fencing at the construction site, the following are taken into account:
- pit dimensions
- operating conditions
- properties of the soil on which construction is carried out.
For successful subsequent construction work, it is very important that the creation of sheet piling for the pit is carried out by specialists who are capable of accurate calculations. Similar requirements apply when performing work to strengthen the bank with plastic sheet piles.
Useful information for you:
Sheet piling, depending on the characteristics of work in the ground and the use of additional fixing elements, are classified into the following groups:
- Independent walls, the stability of which in the ground is achieved solely due to the resistance of the soil. Independent walls are not strengthened additional elements, this type of fencing is used when constructing pits in high-density soils;
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- Sheet piling walls reinforced with transverse struts using steel pipes. This method strengthening is implemented when fencing deep but narrow pits. The pipes are fixed due to the pressure of the opposite walls; vertical supports are not used;
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- Sheet piling walls reinforced with anchor piles. They are used for fencing deep pits (over 7 m), developed in conditions of low-density soil, the bearing capacity of which is insufficient to obtain the required stability of the sheet pile wall. Used as anchors screw piles, which are immersed in increments of 3-4 m at a distance of 5 m from the walls of the pit along its perimeter. After screwing, the fence is tied to the piles using steel cables.
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Important: in soil with high density, for fencing the pit, a flat, z-shaped or trough-shaped tongue is used. In low-density soil, sheet piling pipe-shaped piles are more often used, which, due to their larger diameter, have better stability in the ground.
Technique used
Sheet piling can be carried out using several technologies, for the implementation of which we use different types special equipment.For static immersion of the sheet pile, mobile pressing units are used, equipped with a hydraulic unit that compresses the sheet pile and moves downward along the guide frames, thereby immersing it into the soil.
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For shock and vibration driving, pile driver machines are used - installations on a wheeled or tracked self-propelled base. When implementing the impact driving technology, the pile drivers are equipped with mounted diesel or hydraulic hammers; when implementing the vibration method, they are equipped with vibratory hammers.
Important: the most cost-effective and fastest way to implement sheet pile driving is driving, however, this method cannot be implemented in dense urban areas, since during the operation of impact hammers strong dynamic impacts occur on the foundations nearby standing buildings, which can cause their deformation.
Important: work on the installation of sheet piling must be preceded by calculations aimed at determining the required resistance of the wall to the pressure of soil masses. Based on the calculations, the dimensions of the sheet pile used, the depth of its immersion and the need to use anchors to fix the wall are selected.
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Installation of sheet piling is carried out in the following sequence:
- The sheet pile delivered to the site is unloaded by a jib crane and stored in consumable warehouses along the perimeter of the pit;
- The sheet piling wall is marked;
- The pile driver is moved to the installation site, support staff fixes the gripping mechanism on the sheet pile and the pile driver pulls the sheet pile to the immersion point;
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- The sheet pile is slinged using a crane winch, after which the structure is installed in the driving position;
- The tongue is mated to the head of the hammer, then the verticality of its position is checked and the hammer begins to strike the sheet pile, under the influence of which the structure is immersed in the soil to the designed depth.
The entire sheet piling wall is created in the same way until the fence closes around the pit.
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The installation of sheet piling with a solid wall allows not only avoid falls and landslides, but also provide protection from groundwater and flood waters.
In conditions where ground vibration, which can damage nearby buildings and structures, is unacceptable, sheet pile fencing is installed using the method of leader drilling wells for sheet piles.
Fencing pits: advantages
Let's consider What is the advantage of sheet piling fencing for pits?:
- pit fencing – required condition when constructing adjacent to buildings in use and without the use of sheet piles, it simply cannot be done here
- ability to withstand much greater loads compared to any other structures drilling wells.
We use piling installations on a vehicle base with turntable. This provides high performance teams and short terms of work with consistently high quality.
Areas with limited space for maneuver are not a hindrance for us, and we are ready to begin work the very next day after receiving the application. Contact us - and safe conditions work in your pit will be ensured!
Our company provides sheet piling services -
This is one of the types of rolled metal, developed in its form at the beginning of the 20th century. The product has a wide range of applications from construction to hydraulic engineering. The special shape of the profile makes the tongue the best solution for many construction tasks.
Larsen tongue and groove device
A sheet pile is a hot-rolled product made from steel with a high carbon content. Profile form in cross section resembles a trough with edges equipped with locks - they allow you to fasten products to each other when installing vertical enclosing structures, for example, supporting walls.
Control of the production of Larsen sheet piles is regulated by GOST 4781-85 “Hot-rolled steel profiles for sheet piles. Technical conditions". There is no separate standard for the product, so manufacturers rely on the developed specifications.
The document presents standard sizes sheet pile beam, grade of steel used for production, procedure for quality control and acceptance of products and other important parameters.
Varieties
The product is used in different directions construction, therefore technical specifications, appearance The profile and grade of steel used differ between types.
Larsen sheet pile L4
The profile is made of steel 16KhG (ST3KP). Its characteristics:
- useful width of the product in the center of the lock - 405 mm,
- wall strength is 517-518 kN/m;
- thickness of inclined edges - 9.5 mm;
- permissible resistance 1 l.m. supporting wall - 2200 cm³/m;
- weight of Larsen sheet pile L4 - 74 kg/m;
- weight of 1 m² of structure - 182.7 kg.
Larsen sheet pile L4 is produced at 2 factories:
- Russian Mining and Metallurgical Company;
- "DMK" (Ukraine).
The product is widely distributed in Russia and the CIS countries; it can be purchased from various suppliers in the primary and secondary markets.
Larsen sheet pile L5
For the production of this rolled product, ST3KP steel is used. This is a more powerful profile than L4:
- useful profile width between locks - 420 mm;
- wall strength - 696…800 kN/m;
- permissible resistance 1 l.m. supporting wall - 2962 cm³/m;
- weight of Larsen sheet pile L5 - 100 kg/m;
- weight of 1 m² of structure - 238 kg.
Like L4, L5 sheet pile is produced by the Ukrainian “DMK” and the Russian Mining and Metallurgical Company. You can buy the product throughout Russia at reasonable prices from various suppliers and intermediaries. On sale you can find rolled VL607 - this is an analogue of the L5 sheet pile from the Czech company Evraz.
Larsen sheet pile L5-UM
This rental representative of this type differs from its predecessor in the quality of the steel used for production - it is resistant to corrosion and contains copper.
- Useful profile width between locks is 543 mm;
- wall strength - 906 kN/m;
- thickness of the inclined edge - 11 mm;
- permissible resistance 1 l.m. supporting wall - 3555 cm³/m;
- weight of Larsen L5-UM sheet pile is 114 kg/m.
Other types
Larsen tongues differ not only in technical characteristics, but also in the shape of the lock:
- S-profile;
- L-profile;
- Z-profile.
In all cases, the lock forms a tight connection between adjacent profiles.
Beams made of non-metallic materials are used for various purposes:
- plastic;
- reinforced concrete;
- tree.
However, steel tongues are used most often and are in demand.
Application area
Larsen tongue and groove is used in civil engineering and when constructing hydraulic structures for various purposes:
- temporary strengthening of foundation pits installation work;
- protection of pits from filling with groundwater - the sheet pile connection is completely sealed and retains its properties for several decades;
- strengthening the walls of tunnels, highways and local roads;
- fixing coastlines and protecting them from erosion;
- arrangement of dams, dams, locks, berths, etc. and their repair;
- construction treatment facilities;
- strengthening soils prone to sliding.
The tongues, connected by locks, form a sealed and durable wall that can take significant loads. Products are immersed in the ground, leaving a fence above ground level required height. The installation of sheet piling walls is much more profitable than the installation of concrete and reinforced concrete structures Therefore, metal profiles are most often preferred in cases where it is necessary to contain the pressure of water and soil.
Installation
The method of driving the Larsen sheet pile depends on the length of the product and the characteristics of the soil. There are 3 methods for installing profile piles:
- clogging;
- vibration immersion;
- indentation
The tongue is inserted into the ground according to the design position, the next one is buried inverted 180° relative to the previous one to allow closing mounting lock and so on.
Clogging
This method is used outside urban areas, since vibration transmitted to the ground has a destructive effect on the foundations of nearby buildings and structures.
Hammering is carried out using a special technique - copra. This machine is equipped with an impact mechanism, the force of which on the driven pile is adjusted depending on a number of factors (parameters of the sheet pile, soil).
Larsen tongue driving is the fastest and cheapest method of driving steel support walls.
Vibration immersion
The second most popular method is vibration immersion. This method is used in cases where it is not possible or necessary to hammer in elements of the supporting wall (in reservoirs, on coastlines, on soft soils saturated with water).
Vibration is provided by a mechanism that produces low frequency vibrations. It is hung on excavators, cranes and other equipment.
How the dive occurs:
- the tongue is secured in a vibration mechanism using slings;
- align the stand to the design position;
- the installation presses on the pile, emitting vibration, which helps steel product sink into the ground.
The method does not have a significant effect on the soil; however, its use within dense buildings is limited. In addition, the method has a significant drawback - high price compared to scoring.
Indentation
The most expensive and only method of driving sheet piles permitted for use in urban development is indentation. The process is carried out by a special pile-pressing unit (PVU) on caterpillar tracks. The tongue is attached to the movable mechanism in a vertical position, and the profile is immersed in the ground to a specified depth.
Dismantling
When supporting wall becomes unusable or the need for it disappears, it is dismantled. The Larsen sheet pile is removed using a vibrating machine. Using only a crane is ineffective - the friction forces in the ground are significant, and only short-amplitude vibrations can weaken them.
The tongue and groove are fixed in a vibration installation suspended from a crane, the vibration generator is turned on, and the pulling force is gradually increased.
As a rule, the cost of even used sheet piles exceeds the cost of dismantling them, so the work pays off well. For this reason, organizations that extract sheet piles themselves pay their clients the difference in prices; the latter automatically resolve the issue of selling unnecessary profiles.
Fastening slopes and walls of pits with larsen and pshs sheet piles
This technological map was developed on the basis of a standard technological map.
The work is carried out in the warm season.
doc format
This technological map contains references to the following regulatory documents:
Organization and technology for performing work on the installation of sheet piling from Larsen sheet piles
Before installing a Larsen sheet pile wall, the following activities must be completed:
The issues of carrying out work with underground and above-ground communications have been resolved.
Arranged:
Temporary electric lighting of the work area;
Inventory, tools, equipment, and sheet piles were delivered.
Larsen tongue and groove piles are stacked on 100x100 mm bars.
Requirements for the organization working area
Rice. 1
Technological sequence of installation of sheet piling from Larsen sheet piles
1 Mark the working area and places for immersion of sheet pile elements using a tape measure in accordance with the design documentation.
2 Install the truck crane into working position in accordance with the PPR.
3 Unload the L5-UM elements within the working area into a stack onto 100x100 mm bars and mark the first element of the tongue with a tape measure, measuring 0.5 m from the clamped end of the element, marking it.
Connect the power cables in accordance with the operating instructions;
Connect to the power source in accordance with the operating instructions.
5 Manually move the grip of the vibratory driver onto the end of the nearest sheet pile element and secure it. Using a truck crane, lift the first element of the Larsen L5-UM sheet pile.
6 Install the first element of the Larsen sheet pile into the immersion location using a truck crane.
7 Use a vibratory driver to immerse the first element of the Larsen sheet piling into the ground to a pre-marked mark, while controlling the verticality using a theodolite and level.
8 Manually move the grip of the vibratory driver onto the end of the nearest sheet pile element and secure it. Using a truck crane, lift the second element of the Larsen L5-UM sheet pile.
9 Insert the second element with the locking part into the locking part installed element(Fig. 2).
10 Use a vibratory driver to immerse the second element of the Lersen sheet pile into the ground (until the upper ends align with the previously installed element).
11 Immerse the remaining elements into the ground in accordance with clauses 5.4.8 - 5.4.10 (Fig. 2).
Rice. 2
Carry out an inspection with the execution of an inspection report of critical structures and the executive diagram.
Notes:
When constructing a Larsen sheet pile wall under special conditions:
To maintain the straightness of the sheet pile wall, the immersion of the sheet pile elements should be carried out in rearrangeable inventory hinged or floating guides;
To speed up the work of loading steel sheet piles, if the loading equipment has sufficient power, it is necessary to carry out advance assembly of sheet pile elements into packages with their fastening by welding;
When driving a sheet pile row from individual elements or assembled packages, to prevent it from tilting during driving, the wall should be installed in the guides, and after that the tongue should be immersed in the wall by periodic repeated passes;
When installing closed loop sheet piling corner elements can be manufactured on site by welding standard elements;
List of executive documentation
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TU 14-2-879-89. |
Operational quality control of Larsen sheet piling installation
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Item control |
Tool and method of control |
Frequency of control |
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Marking of tongue and groove elements |
Marking distance |
First element |
In accordance with paragraph 1 |
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Immersion of sheet pile elements |
Verticality of immersion |
Theodolite, level |
First element |
±0.5% |
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Immersion depth |
Visually |
Each element |
In accordance with SNiP 3.02.01-87 |
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Unit change |
Qty |
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Flatbed vehicle - 10 t (KAMAZ-5320) with trailer dismantled |
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Truck crane - 25 t (KS-55713-1) |
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Power plant 80 kW |
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Unit change |
Qty |
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Level included |
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Mittens |
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Roulette 50 m |
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Podstropnik |
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Theodolite |
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Bayonet shovel |
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Construction level |
2. Installation of sheet piling from PShS sheet piles
Before starting the installation of a wall made of PShS sheet piles, the following measures must be carried out:
A geodetic alignment base was completed and inspected with the execution of an inspection report for the geodetic alignment base of a capital construction project.
The issues of carrying out work with underground and above-ground communications have been resolved.
Arranged:
Areas for parking and repair of equipment;
Access roads;
- temporary electric lighting of the work area;
- temporary protective fencing of the work area.
A temporary power supply line has been installed.
Inventory, tools, equipment, and PShS panels were delivered.
Recusal completed surface waters(of necessity).
PShS panels are stacked on 100x100mm bars.
Requirements for organizing a work area
Rice. 3
Technological sequence of installation of sheet piling from PShS sheet piles
1 Mark the working area and places for immersion of sheet pile panels using a tape measure in accordance with the design documentation.
2 Install the truck crane into working position in accordance with the PPR.
3 Unload the PShS panels within the working area into a stack on 100x100 mm bars and mark the first panel with a tape measure, measuring 0.5 m from the clamped end of the panel, mark it.
4 Hang the V-16-60 vibrating hammer onto the hook of the truck crane and bring it into working condition:
Connect the power cables in accordance with the operating instructions;
Connect to the power source in accordance with the operating instructions.
5 Manually place the grip of the vibratory driver onto the end of the nearest PShS panel and secure it. Use a truck crane to lift the first PShS panel.
6 Install the first PShS panel to the immersion site using a truck crane.
7 Using a vibratory driver, immerse the first PSH panel 11.5 m into the ground to a pre-marked mark, controlling the verticality of the immersion using a theodolite and level.
8 Manually place the grip of the vibratory driver onto the end of the nearest PShS panel and secure it. Lift the second PShS panel using a truck crane.
9 Insert the second panel with the locking part onto the cam (or with the cam into the locking part) installed panel(Fig. 4).
10 Use a vibratory driver to immerse the second PShS panel 11.5 m into the ground (until the upper ends align with the previously installed panel).
11 The remaining three panels are immersed in the ground in accordance with clauses 10.4.8 - 10.4.10 (Fig. 4).
12 Place machines and mechanisms in transport position in accordance with the operating instructions.
Rice. 4
Carry out an inspection with the execution of an inspection report of critical structures and an as-built diagram.
Notes:
The electric motor of the vibrator must be powered from an independent network that has no loads.
This sheet piling kit is designed for multiple uses.
When constructing a wall made of PShS sheet piles under special conditions:
To maintain the straightness of the sheet pile wall, the sheet pile should be immersed in rearrangeable inventory hinged or floating guides;
To speed up the work of loading steel sheet piles, with sufficient power of the loading equipment, it is necessary to carry out advance assembly of the PShS panels into packages with their fastening by welding;
When loading a row of sheet piles from individual panels or assembled packages, to prevent it from tilting during driving, the wall should be installed in the guides and after that, the PShS panels should be immersed in the wall by periodic repeated passes;
When installing a closed loop sheet piling, the corner elements can be manufactured on site by welding standard panels;
The need to secure the sheet pile from the effects of waves and ice, as well as circuit diagrams its bracing must be specified in the PIC.
List of executive documentation
Quality control and acceptance of completed work
PShS panels must have a document certifying their quality and comply with the requirements of the following regulatory documentation:
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Name of the process to be controlled |
Item control |
Tool and method of control |
Frequency of control |
Person responsible for control |
Technical criteria for quality assessment |
|
Marking of tongue and groove elements |
Marking distance |
First panel |
In accordance with clause 2 |
||
|
Immersion of sheet pile elements |
Verticality of immersion |
Theodolite, level |
First panel |
In accordance with SNiP 3.02.01-87 ±0.5% |
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|
Immersion depth |
Visually |
Each panel |
In accordance with SNiP 3.02.01-87 |
List of equipment, tools, inventory
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Name of machines and mechanisms |
Unit change |
Qty |
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Flatbed vehicle - 10 t (KAMAZ-5320) with trailer dissolution |
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Truck crane - 16 t (KS-55317-1) |
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Vibratory hammer V-16-60 (with a set of cables) |
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Power plant 80 kW |
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Name of tools and equipment |
Unit change |
Qty |
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Level included |
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Mittens |
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Roulette 50 m |
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Noose lanyard |
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Theodolite |
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Bayonet shovel |
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Construction level |
Rice. 1
Rice. 2
Rice. 3
Rice. 4
1- panel;
3- cam;
4, 5 - weld;
6-axis of the locking connection.
Vibratory hammer V-16-60
The vibratory driver is designed for immersion into water-saturated sandy and lamellar soils and extracting from them various pile elements weighing up to 3.5 tons. This vibratory driver is designed using the self-synchronization effect of two dynamically coupled vibration systems, which eliminates the use of rigid kinematic coupling (chain, belt, etc.) .d.) and increase the efficiency of drive electric motors. See also choosing a vibratory hammer
1 When working with vibration machines equipped with shock absorbers, the lowering speed of the crane hook must be such that the vibration loading is partially braked by the crane. This ensures that the sheet pile is inserted vertically. On last stage diving (1.5-2 m), the cable can be loosened and the dive can be carried out without braking.
2 When immersing a sheet pile with a vibratory loader without a shock absorber, the lowering speed of the crane hook must be such that the crane does not slow down the immersion of the sheet pile (package).
3 Sheet piling fences for pits should be counted on for stability of position and for the strength of the material of their elements, not only at the stage of complete removal of soil and water from the pit, but also during the development of the pit and installation of spacer fasteners, as well as backfilling of soil and removal of fasteners.
4 For sheet piling fences buried in sand or sandy loam, in addition to the specified calculations, it is necessary to check the depth of driving the sheet piling below the design level of the bottom of the pit, based on the condition of preventing the possibility of removal (influx) of soil into the pit when pumping water out of it without installing a waterproof cushion and accept ( regardless of the calculation results) at least 2 m, and in other soils or when installing a concrete waterproof cushion in a pit - at least 1 m.
5 The top of the sheet piling must be positioned above the maximum possible level groundwater by 0.2-0.4 m and above the accepted working water horizon in the river by at least 0.7 m.
2. Sheet pile deviations and ways to eliminate them
1 Rejectednot the tongue from the vertical in the plane of the alignment (fan).
To prevent fanning, it is recommended to install the vibratory driver with a shift from the center of gravity of the loaded sheet pile (or package in the direction opposite to the deviation by an amount equal to approximately 10-20% of the width of the sheet pile or package). The required displacement value of the immersion projectile axis is determined experimentally. As one of the measures to eliminate fan-shaped deviations of steel sheet piles in the plane of the sheet pile wall, it is recommended to close the free lock from below with a plug that protects it from clogging with soil and at the same time creates a restoring moment to the sheet pile.
2 OffThe movement of the tongue from the vertical in the direction perpendicular to the alignment (leaving the alignment).
Correction of the emerging inclination of the sheet piling wall, if it does not exceed the permissible value, is carried out gradually when immersing subsequent sheet piles by deflecting the load-bearing cable of the crane supporting the vibratory driver or hanging hammer guide to the opposite side, or by using the force of special guys.
If the slope of the tongue exceeds the permissible level, it should be pulled out and loaded again. If it is impossible to remove the sheet pile, the issue of straightening it is resolved in agreement with the design organization.
3 Byloading of the sheet pile below the design mark due to its removal by the adjacent loaded sheet pile.
To prevent this, deviations immersed to design marks should be joined together by welding or temporary bolted overlays.
If the sheet pile goes below the design mark, it can be corrected by extending it with a piece of sheet pile and joining it by welding with overlays.
4 Underloadedcutting the sheet pile to the design level.
Under-immersion of the sheet pile to the design level, caused by an increase in resistance in the lock, is recommended to be eliminated by single- or double-row lifting of the sheet pile by 0.5-0.8 m and its subsequent re-immersion. If under-immersion is caused by an encounter with an obstacle, which is characterized by a sharp slowdown in the immersion process, you should stop immersing this sheet piling and proceed to immersion of adjacent sheet piles, the nature of the immersion of which may make it possible to establish the cause and degree of randomness of this phenomenon. If loading the subsequent sheet pile does not encounter any difficulties, you should return to the stopped sheet pile and try to load it further along two adjacent guide sheet piles.
If the underloading of the sheet pile could not be eliminated, the issue of further measures is resolved jointly with the design organization.
Download the full version of the technological map in editable format after registration
To strengthen the walls of the pit during construction work, use different technologies, among which the most common is sheet piling made of pipes. The use of post-consumer materials makes the construction protective structure much cheaper than using special sheet pile profiles for these purposes.
Type of sheet piling using pipes
In construction, tongue and groove piles are usually called driven piles, which can be wooden, reinforced concrete or metal.
The essence of such strengthening is that first, sheet pilings (piles) are driven along the perimeter of the future pit to the required depth, and only after that the soil is excavated. Thanks to this, the collapse of the walls is prevented as it deepens, the pit itself is obtained with a strictly specified correct shape, and displacement of the structures of neighboring objects is avoided.
Properties of pipe sheet piling in comparison with other types of structures
Experts unanimously consider the only advantage of such strengthening to be its low cost. Unlike more expensive materials, such as Larsen tongue and groove, the use of pipes has significant disadvantages:
- Their use does not allow obtaining a monolithic waterproof surface, therefore fencing is not used in the construction of hydraulic structures and in conditions of high groundwater horizons.
- Due to the thin section of the material walls and large area when entering the ground, when it is driven in, the edges are significantly deformed.
- Since the elements of the device do not have a locking clutch, it is difficult to ensure their smooth entry into the ground, therefore, with increasing depth, the elements of the fence will deviate significantly from the given plane.
As a rule, sheet piling fencing of a pit made of pipes, the technology of which involves their one-time, non-removable use, simultaneously serves as support posts for forming formwork for carrying out concrete works. In this case, the drill-injection method of driving piles is used, when their cavity is filled with a water-cement solution. When the pipe is pulled out, a large cavity is released, which will cause many years of subsidence of the home paths.
Methods for making sheet piling fencing of a pit
Vibration loading of sheet piles
The most common method of installing sheet piles is vibration immersion. First, a well is drilled and a pipe is immersed into it. To secure it more firmly, the well is first filled with sand-cement or clay mixture. The installation of sheet piling for a pit made of pipes, pursuing the goal of maximum savings, involves the use of the vibro-immersion method as the most economical method. existing methods. In this case, the pipe experiences minimal load during immersion, which prevents its deformation at the initial stage.
The pile can be driven by screwing. To do this, a tip is welded at one end of it, providing a spiral movement.
Important! Before driving piles, geodetic surveys are carried out to determine soil properties and groundwater levels.
When using pipes, driving can be used at the final stage of immersion to achieve the desired depth or if passage fails when vibration immersion is less than 1.5 cm/min.
The depth of driving the sheet piles must be above the groundwater level. When making deep pits, sheet piling is made in two tiers. In this case, the upper tier is driven several meters wider than the design dimensions, and when the recess reaches 2/3 of the length of the driven piles, the second tier is driven in to the required size.
In deep pits, fastening with ground anchors is used.
- Using struts. The parameters of the struts are calculated in each case separately.
- Anchoring with additional piles and rods. It is used in cases where fastening from the inside will interfere with the work. In order not to interfere with movement, the rods are recessed into the ground.
- Anchoring with drilling of additional piles obliquely into the wall.
- Cantilever mount. In this case, the pile is supported by deep penetration into the ground, when the depth of the pit does not exceed 2/3 of its length. The depth limits using this method of fastening, made using the bored method, is 10 m.
- Spacer fastening using spacer frames or telescopic tubular spacers.
Mounting options
As they deepen, the installed piles are laid wooden blocks, forming a solid wall, or fence.
Basic rules for performing sheet piling strengthening
To construct the fence, large diameter pipes are used, ranging from 219 mm to 630 mm. Before starting work, the axes of the pit are laid out by drawing out the design dimensions in situ. While driving the supports, you must constantly monitor their vertical position. When driving, it is recommended to use wooden headers. SNiP allows a maximum deviation of the top of the pile from the plane of the fence of 15 cm. Support pillars can be secured with a horizontal belt if the depth exceeds 4 m. Such belts are made from an I-beam. To ensure uniform loading, wedges are inserted between each pile and the belt. The struts and spacers are attached to the belt beams. At a depth of more than 10 m, two or more belts are made, and the top one should be at least 1 m from the top of the pit.
Important! If it is necessary to remove piles for their repeated use, it is important to follow a safe procedure for dismantling the struts and struts.
To prevent corrosion, metal piles are sometimes coated with special primers.
Upon completion of work on the implementation of the sheet piling, an act of laying out the axes of it and the pit, an as-built survey, and an act of acceptance of work are drawn up.
The calculation of sheet piling for a pipe pit is made using special programs, which, due to their high cost, can be afforded by large specialized organizations. One of the simplest, the SpIn program, calculates the ratio of the diameter of the pile, the depth of its driving and the parameters of struts and struts. Manual counting will take a long time and requires in-depth knowledge.
Screenshot of Spin
The technology for performing sheet piling strengthening of a pit requires the use of special equipment and knowledge of the rules for calculating the structure, which ensures its strength and safety. Therefore, it should be entrusted to specialists who have licenses to carry out such work and issue official documentation.
Price
The cost of services for the manufacture of sheet piling fencing for a pit from pipes is given in the table.
Firm "StroyAllianceGroup»
Sheet piling barriers were developed to strengthen the walls of excavations during construction work. Such fencing reliably protects workers and equipment from ground collapses.
In the territory Russian Federation The method of static indentation of tongues began to be used only in the late 90s of the 20th century. When constructing protective structures from sheet pile profiles in America and Europe, most are built using this method.
Initially, the tongues were made of wood. Distinctive feature tongue and groove board was the presence of a tongue and groove on the sides of the board. They were intended to reliably connect individual boards into a single shield.
With the development of construction skills and the growth in the scale of construction, reinforced concrete ones replaced wooden tongues. Such a design can be not only temporary fencing, but also in the future bear the supporting load during the construction of the building.
The disadvantage of this type of sheet piles is their low resistance to difficult soils, which is why they often go to the side when they hit a solid obstacle. Cracks also often appear, since reinforced concrete is very sensitive to bending.
The most economical options is the pressing of metal sheet piles.
After work in the pit is completed and the piles are no longer needed, Larsen metal sheet piles can be pulled out and used in the construction of other objects. This greatly reduces the cost of the method.
Methods for driving sheet piles into the ground
Main in modern construction There are 3 ways to immerse the sheet pile:
- Immersion driving;
- Static indentation.
Immersion driving
This method was used to drive the first piles in construction. The main advantage is its technological simplicity and availability of all necessary equipment.
The disadvantages include the need for powerful and energy-consuming installations. Also, when such equipment operates, it produces a lot of noise and a high impact on the ground.
Helpful advice
All vibration loads have Negative influence on the condition of neighboring buildings, creating cracks in the foundation and walls.
If the tongue and groove hits some obstacle during impact driving, it may become deformed, and along with it the tongue-and-groove fastening lock.
Vibration loading of sheet piles
Vibration immersion of the sheet pile is more than economical option in terms of energy consumption. Also, the level of noise and vibration generated is noticeably lower than that of impact technology. Which has a positive effect on the possibility of carrying out work near residential buildings and protected cultural sites.
But the immersion mechanism itself under the influence of vibration makes it impossible to use such equipment near subway tunnels or large pipelines and other highways.
Static indentation of tongue and groove
The most modern technology This is the static indentation of the Larsen tongue.
An excellent option if you need to carry out work in densely populated areas of large cities or near architectural monuments.
This method will be especially relevant in areas with dilapidated buildings, landslide zones, where any impact can lead to an emergency.
Sheet piling fencing for a pit in Sheremetevo, made by specialists from ArktikGidroStroy
Sheet piling in Moscow, made by specialists from ArktikGidroStroy
Sheet piling fencing of a pit made from Larsen sheet piles with spacers, made by specialists from ArktikGidroStroy
Indentation of the sheet pile performed by specialists from ArktikGidroStroy
Vibration driving of pipes and sheet piles during the construction of a temporary bridge, performed by specialists from ArktikGidroStroy
Advantages of the static indentation method
The main advantages of using the indentation method when driving sheet piles are:
- Suitable for working near residential buildings and cultural objects;
- Possibility to carry out work near large pipelines and metro lines due to the complete absence of vibration and shock loads on the ground;
- High speed of construction of the barrier and savings in the construction budget;
- The settlement of the entire barrier is uniform, as is the process of immersion in the ground;
- The use of modern special equipment allows you to monitor the dive online and make the necessary adjustments;
- This technology is environmentally friendly;
- Final load bearing capacity of all piles that were installed using the static indentation method is higher on average by 10% than for piles installed using the classical impact method.
Technology for installing sheet piles using the indentation method
With the static method of pressing a sheet pile, it is installed at the planned immersion location, after which it is pressed into the ground using a hydraulic drive. Modern technology allows you to apply pressure from a ton to several tens of tons.
Due to its small cross-sectional area, a sheet pile cuts into the ground much more easily than a classic reinforced concrete pile.
Helpful advice
Immersion of the sheet pile using the indentation method allows you to avoid restrictions when working near residential buildings due to the complete absence of vibration and noise. This is especially important when carrying out work within large cities.
Watch the video to see how sheet piles are installed in our company:
Machinery and equipment used
The main force used during the indentation pile driving procedure is a constant static load. For such purposes, extremely powerful construction equipment is used.
All pile driving machines are designed on the principle of lateral wedge gripping of the sheet pile and immersing it in the well, which is prepared in advance.
Modern electronics help to adjust the angle of insertion of the sheet pile in a timely manner and ultimately obtain a perfectly even row of piles. It is also possible to create sheet piling barriers in round and angular configurations.
Several types of equipment are most widespread in the market for tongue pressing services:
- Hydraulic pile driving unit (HPU) TITAN DTZ Mainly used to create pile foundation under the building. The maximum force is 320 tf;
- When working in dense urban areas or the need to organize a large pile area, use the SUNWARD ZY J120 installation, which is completely silent, environmentally friendly and suitable for all types of piles;
- SVU-V-6 is a completely independent and standalone installation, capable of performing the entire range of work with sheet piles and moving to to the right place installations.
Types of Sheet Piling
Currently on the market are following types sheet piling:
- Larsen tongue and groove is the most popular type of tongue and groove at the moment. Technologically, it is a metal profile various forms, made of high quality metal. Larsen tongue and groove sheets come in a trough shape or a Z-shape. The side walls have special curves that act as locks for connecting individual tongues into a solid structure. As a result, such tongues form a strong and monolithic wall, which reliably protects against collapses and other incidents;
- Standard metal tongue - used in cases where static pressing of a Larsen tongue is too expensive. After installation, the iron tongues are removed from the ground and can be reused if they were not damaged during installation.
- Concrete sheet piles are more expensive than iron ones, but after construction they continue to perform a supporting function. They are most often used in the construction of multi-storey buildings.
- Wooden ones are practically no longer used, since they are not able to withstand high loads and cannot be reused.
Our advantages in the installation of sheet piling
Our specialists are always ready to advise you free of charge on any issue of sheet piling, as well as to guide you through the range of sheet piles.
We provide a service for the supply of used sheet piles and the removal of already used Larsen sheet piles.
We have accumulated great experience for the implementation of a wide variety of objects of any complexity. The start time for work from the date of application is 48 hours.
A key feature of cooperation with our company is that we sell Larsen sheet piles with the possibility of buy-back. This procedure will help you return up to 80% of the original cost.