Larsen pile SPIV
Steel sheet piles – Larsen not only used in temporary works but also can is considered a construction material, with unique properties, suitable for some load-bearing parts in construction works.
Depending on the level of applied load, the retaining wall can use only steel sheet piles or a combination Use steel sheet piles with steel pipe piles or trough-shaped steel piles (King pile) to increase the ability to withstand bending moments.
In terms of size, steel sheet piles – Larsen Plate width varies from 400mm to 750mm. History Using piles with large slab widths is often more economical than piles with small slab widths because fewer piles are needed if calculated on the same length of retaining wall. Furthermore, reducing the number of piles used also means saving time and costs for the pile lowering process, while also reducing the amount of groundwater flowing through the pile's keyways.
1. Larsen wood has been pressed
Larsen pile pressing robot
2. Larsen wood has been pressed
Larsen pile in tubular form SPSP (Nhat Tan bridge, Hanoi) – reference
Outstanding advantages of steel sheet piles:
- The ability to withstand dynamic stress is quite high (both during construction and during use).
- Great bearing capacity while the weight is quite small.
- Steel sheet piles can be easily connected with welded joints or bolts to increase length.
- Steel sheet piles can be used many times, so they are economically effective.
The disadvantage of steel sheet piles is corrosion in the working environment (when using steel sheet piles in permanent structures). However, this drawback can now be completely overcome by protection methods such as anti-corrosion coating, galvanizing, anti-electrochemical corrosion, or you can use steel sheet piles made from solid steel. has exceptionally high corrosion resistance.
In addition, the level of corrosion of steel sheet piles over time in different environments has also been studied and recorded. Accordingly, depending on the pre-specified service time of the project, the designer can choose the type of steel sheet pile with the appropriate thickness considering this corrosion.
In the cold stamping method, a roll of steel sheet will be pulled through a chain consisting of many continuously arranged rolling rolls, each rolling roll contains rollers that can change position, molding the steel plate from shape. initially flat into a folded shape like a steel sheet pile.
Steel sheet piles manufactured by this method must be strictly tested for their bearing capacity as well as the clearance of the key groove before leaving the factory. The cost of this type of pile is usually cheaper than the hot rolling method.
With the ability to withstand high dynamic loads, it is easy to see that steel sheet piles are very suitable for port projects, piers, dams, basement construction, high-rise building foundations, in addition to soil pressure, are also subject to the force of ocean waves as well as the impact force of ships when sideways.
Larsen piles for rent
Cu Larsen constructs port projects
Use Larsen piles as a water barrier to construct bridge piers
Cu Larsen applied to construct the basement of hospital 7A
In the world, there have been many port projects designed in which steel sheet piles (often combined with anchor wall and anchor bar systems) act as retaining walls, and soil is filled inside.
and above is a reinforced concrete port foundation structure with a steel pipe pile foundation or pre-stressed reinforced concrete pile below. This steel pile wall is also attached to concrete like pipe piles.
Conventional anchor wall systems also use steel sheet piles but are smaller in size and length than the main wall. Tie rods are steel bars with diameters from 40mm to 120mm that can be adjusted in length as required.
Designing port structures using steel sheet piles can be more cost-effective because if steel sheet piles are not used, the number of pipe piles underneath the port foundation structure will have to increase significantly and additional inclined piles will have to be designed. to completely absorb the horizontal loads acting on the port foundation structure.
Besides port projects, many embankments, canals, and flow improvement projects also use steel sheet piles due to their convenience, quick construction time, and good load-bearing durability. For road projects and traffic tunnels passing through complex steep hillsides or along river banks, using steel sheet piles to stabilize slopes or make embankments is also quite effective.
In civil works, steel sheet piles can also be used to make basement walls in multi-storey houses or in underground parking lots instead of reinforced concrete walls. Then, similar to the topdown construction method, the steel sheet pile itself will be lowered first to make a soil retaining wall to serve the construction of the excavation pit.
The steel sheet pile itself will have steel welded on the inside so that it can adhere firmly to the concrete of the edge beams that will be poured later.
On the key grooves between the steel sheet piles, bitumen will be inserted to prevent water from flowing into the basement or a continuous welded seam can be used to prevent water (in this case, wide sheet piles should be used to limit the number of key grooves). .
Larsen pile applied to construct storage tanks for Vina Kraft paper factory - My Phuoc 3 Industrial Park
In design, steel sheet piles, in addition to checking the durability conditions under horizontal load, must also check the fire resistance conditions to choose the appropriate thickness. The surface of the steel sheet pile inside is painted to meet aesthetics and also to protect the steel sheet pile against corrosion.
Not forgetting to mention the field where steel sheet piles are used the most is making soil or water retaining walls when constructing temporary excavations.
We can see steel sheet piles used everywhere: in the construction of basements of civil houses, industrial buildings, construction of bridge abutment foundations, underground water supply and drainage systems, pumping stations, tanks, infrastructure, Construction of pressure valves for canals,...
Depending on the depth of the excavation as well as the horizontal pressure of soil and water, steel sheet piles can stand independently (cantilever diagram) or combined with one or more shaped steel bracing systems (continuous beam diagram).
Most bracing systems are made from I-shaped steel for convenience in construction. Experience Preventing water from flowing through the key grooves of steel sheet piles in these temporary works is used Using a mixture of cement mixed with clay, it is both cost-effective and highly effective (almost completely water resistant).
Bracing system combined with Larsen sheet pile wall
Obviously, steel sheet piles are not simply a means of serving the construction of excavations temporary but can also be considered a type of construction material used permanently in some construction projects.
Steel sheet pile products offered on the market are also very diverse in shape and size (slab width, height, thickness), so it is quite convenient to choose a suitable product.
Of course, for a specific project there are always many different design solutions using different types of materials. And then, choosing whether or not to use steel sheet piles depends on many factors such as geological terrain conditions, groundwater level status, cost, construction conditions...
However, one thing is certain: investors have more and more opportunities to choose to achieve their goals.