We find out how to dismantle the fastenings of the vertical walls of the pit?

It’s crucial to approach the task of removing the fastenings of vertical walls in a pit with careful planning and the appropriate techniques. In order to move forward with the work on a variety of construction and renovation projects, it is imperative that these fastenings be removed safely and effectively. Knowing the procedures and equipment needed will help the work go more smoothly and efficiently, whether you’re working with retaining walls, concrete formwork, or other structural components.

Vertical wall fastenings must be disassembled in a number of safe and efficient steps. Usually, these fasteners are used to hold up makeshift buildings or support walls while they are being built. The methods used can range from manual dismantling to the use of heavy machinery, depending on the type of fastening and the material used. The objective is to remove these fastenings without endangering the workers’ and the site’s safety or causing damage to the nearby structures.

During this process, the type of fastening that is used is one of the most important factors. Bolts, anchors, and other mechanical fixtures that hold the vertical walls in place are common techniques. To remove each type, particular instruments and methods are needed. For example, to remove bolts from concrete or other materials they are embedded in, they may need to be unscrewed or cut, and anchors may need to be drilled or ground.

It’s critical to evaluate the fastenings’ and the surrounding materials’ structural integrity before starting any disassembly work. This assessment guarantees that the procedure is carried out safely and aids in determining the best course of action. It might entail looking for any indications of corrosion, deterioration, or damage that might compromise the effectiveness of the disassembly procedure or the stability of the vertical walls.

Why is it necessary??

Following excavation manipulations, the fastenings supporting the pit’s vertical walls are removed.

During relief work on the foundation pit, the fastening device itself is required to secure the vertical walls and keep them from collapsing. The fasteners are disassembled once these processes are finished. It is necessary to carefully remove every auxiliary element to the earth’s surface.

Digging at a deeper depth than usual results in the walls becoming stronger. For instance, the digging depth should not go deeper than one meter in bulk, gravel, or sandy soil.

Work involving auxiliary excavation is done safely and with reference to relevant regulatory documents.

Other soils are also subject to restrictions:

• in loamy soils – no more than 1.25 m;
• in clayey ones – no more than 1.5 m;
• in dense ones – no more than 2 meters.

In dense soils, excavation and wall strengthening must be done slowly and carefully if the depth is greater than two meters. Regulation papers govern the disassembly process that follows. For instance, SNiP III-4-80 is used in the construction industry to adhere to all safety regulations.

GOST 25-100-95 is used to assess the work’s progress because it provides a clear classification of the current soils. You can provide a procedure for removing the pit walls’ fastenings if you are aware of the type of soil that is present on the surface. Also in use are SNiP 12-03-2001 and SNiP 12–04-2002.

When to disassemble?

Disassembly is done when main pipelines are laid, when subways are built, when hydraulic engineering is used, and when building railroad and road tunnels.

After the primary excavation is completed, auxiliary work starts.

These consist of opening safety containers, taking fasteners off, inspecting machinery, and backfilling the path. Compaction of the soil also happens at this point.

Wall fastening removal requires the presence of a foreman.

Fastening disassembly is only permitted in stable soils where labor does not endanger people. The auxiliary excavation work is skipped at this stage if the soils are loose, gravelly, or loamy.

Disassembly of fasteners should be done from bottom to top if they are installed from top to bottom. In the event that there is groundwater close by, fence installation is also required.

Wooden components that have rotted or gotten wet are disassembled only after the work supervisor has thoroughly inspected them.

Before beginning work, a specialist thoroughly inspects the pit if the excavation was done during the winter and the dismantling takes place during the thaw period. The high level of moisture increases the possibility of soil sliding or fastenings destroying themselves, both of which can result in potentially fatal circumstances.

In this piece, we explore the useful procedures and techniques for securely removing the fasteners holding up vertical walls in construction pits. Knowing the right methods is essential for efficiency and safety when working with either permanent structures like retaining walls or transitory supports like shoring. We look at strategies like strategic cutting, mechanical disassembly with the right tools, and the significance of evaluating structural integrity all along the way. This guide intends to ensure that dismantling operations are carried out with accuracy and safety at the forefront by offering concise, practical insights to both professionals and do-it-yourself enthusiasts.

How is it carried out??

The pit needs to be strengthened after the dirt has been removed; this is accomplished by using structures, elements that are vertical and horizontal, and a wooden fence.

Elements of a horizontal mount are as follows:

• wood;
• reinforced concrete;
• metal.

When marking a pit’s bottom above groundwater level, walls are strengthened horizontally.

Additionally, this technique has proven effective when building intricate and small objects, provided that the height of the loose wall component is no more than 50 cm. When there is little space between the walls, the walls are strengthened horizontally.

Horizontal fastenings are dismantled in the course of construction. Here’s the crucial requirement: work must be done cautiously and slowly. There is a chance that the entire structure could collapse if one of these fasteners—which support vertical walls like struts—is removed.

The insertion of machine technology is restricted due to the large number of cross braces, and the removal of the struts may result in the walls losing their stability.

The tasks are completed in this order:

1. Through boards protruding as spacers are sawn through. They need to be sawed into 2-3 pieces.
2. Temporary spacers are prepared and installed.
3. Fastenings are disassembled.
4. Structural elements are fed to the surface above the pit.

In the event that the soil is cohesive and stable, there will be continuous fastening, with a maximum distance of 1.5 m between posts. Disassembly will take place at a depth of 0.27 m. Dismantling is done from a depth of up to 0.39 meters in loose and unstable soil.

The process of dismantling racks and tongues

Racks and tongues are used to reinforce the walls of the pit in order to reduce the possibility of nearby buildings being destroyed. It is necessary to disassemble the racks after the task is finished. In accordance with document 3.02.01, all pits deeper than two meters have SNiP sheet pile elements installed. This will stop the soil from crumbling and the pit’s walls from collapsing.

Vertical posts and tongues can be:

1. wooden;
2. reinforced concrete;
3. metal.

Tongues and racks are set in at a depth of one meter on sandy soils and 1.25 meters on sandy loams.

Sheet piles are buried to a minimum of two meters in hard and dense soils and 1.5 meters in loam and clayey soils of the pit walls. Sheet piling is used to secure the walls if the soil is wet and saturated.

How the procedure operates

• starts from the bottom as the pit is filled;
• spacers and tongues are also removed as backfilling proceeds;
• the pressure bars are gradually removed;
• when backfilling is completed, vertical boards and sheet piles are pulled out.

Because pulling out the boards mechanically is challenging and time-consuming, a specialized lever is used.

Dismantling fastenings with piles and a wooden fence

If the weak soil prevents a hole from being dug all the way down, the walls are strengthened with piles surrounded by a wooden fence.

Because of the large width and complex shape, transverse braces and standard strengthening methods are not appropriate in this situation.

Before any digging is done, wooden cores are inserted between the piles. They are separated by 1.5 to 2 meters.

The piles themselves are driven to a pit depth that is adequate, and boards are placed between them all the way around the perimeter. These fastening components are placed in pits that have already been excavated as well as in those where spacer installation is not feasible.

When tearing down piles with a wooden fence, begin at the bottom and saw down the fence boards first. As the pit is backfilled, the process takes place. One board at a time, the fence is taken down. At the very end, after the soil has been compacted, the piles are removed, leaving their ends on top.

Possible mistakes

Disassembling the pit fastenings precisely is where a lot of mistakes happen. For instance, the bottom row of spacers is removed when laying a foundation. Given that there is a significant risk of ground collapse and that the lower boards are left unsupported, this is a serious infraction.

It is preferable to remove the boards into the foundation itself to avoid this from occurring. An additional error: the wrong disassembly order. It is necessary to begin at the bottom and work your way up gradually. It is not possible to eliminate the top components before the bottom ones. The remaining piles and fasteners must be removed once the hole has been filled.

During disassembly, every component of the structure needs to be moved upward. Many builders neglect to check the fastenings’ condition before beginning work, which can have detrimental effects like ground collapse and injuries. An expert must assess the bottom’s condition before beginning any work on it.

A methodical approach and careful planning are necessary when removing the fastenings of vertical walls in a pit. The safety of everyone should always come first. Using the proper safety gear and ensuring the stability of the nearby structures are essential steps in this process.

Starting with the removal of any visible braces or supports holding the walls in place is one efficient strategy. This frequently calls for specialized tools, like hydraulic jacks or excavators fitted with tools made just for the job. Dismantling slowly and carefully reduces the chance of structural damage or collapse.

It’s also important to comprehend the kind of fastenings that are being used. Soil nails, mechanical anchors, and tie-backs all need particular removal methods to be used safely. Using structural plans as a guide or consulting a professional can help determine the best course of action.

Finally, it’s critical that everyone involved in the disassembly process communicates clearly with one another. This guarantees that everyone knows their responsibilities, adheres to safety procedures, and works to finish the project successfully and safely.

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