How deep should the pile be drilled to ensure safety?
Piles are an essential component used to support and transfer the weight and load of a building to the ground. The load transfer of a pile occurs through the frictional resistance between the pile surface and the surrounding soil or through direct load transfer to the underlying soil or bedrock. The main purpose of using piles is to prevent the building or structure from settling or sinking into the ground.

For small-scale buildings, the piles used are generally shorter in length and fewer in number. However, larger buildings may require a greater number of piles or longer piles to transfer the load to deeper layers of soil and bear a higher load capacity. If the pile extends to the level of hard soil, it can directly transfer the load from the building to the hard soil layer.

How do piles bear the load?
Piles bear the load through two main types of forces: "skin friction" and "end bearing."

1. Skin Friction: This force is generated by the frictional resistance between the pile surface and the surrounding soil. The magnitude of this force depends on the type of soil (each soil type has different skin friction properties) and the characteristics of the pile surface.

2. End Bearing: This force occurs at the pile tip, where the pile rests on a firm soil layer. The magnitude of this force depends on the type of soil, such as the presence of voids between soil particles. Soils with more voids have a lower load-bearing capacity, while compacted sands have a higher load-bearing capacity.

In general pile design, for skin friction piles, the focus is on the size and length of the pile to generate sufficient lateral friction to support the applied load. For end bearing piles, the design aims to have the pile sit on a compacted sand layer.

Types of piles used in construction can be broadly categorized into three main types based on their manufacturing and usage characteristics:

1. Spun Piles: These piles are produced by spinning concrete in a mold at high speed. This process results in a dense and strong concrete core with embedded steel reinforcement. Spun piles can be driven or drilled and are suitable for high-rise buildings that require strength to withstand wind loads and earthquakes.

2. Bored Piles: Bored piles are constructed by drilling a hole and then placing steel reinforcement and concrete into the drilled hole. They come in various lengths and sizes as specified. Bored piles are suitable for projects that require high strength and load capacity.

3. Prestressed Concrete (PC) Piles: PC piles are manufactured by placing concrete into a mold that contains prestressed steel wires or strands. The concrete is then compressed to enhance its strength. PC piles are used in construction projects that require high strength and durability in various environmental conditions.

Siam Wire Industries (SIW) offers PC Wire and PC Strand, which are the primary components used in the production of prestressed concrete piles. SIW has gained recognition in over 50 countries worldwide and provides post-sales services, including on-site wire pulling tests for customers. These services ensure customer confidence in using SIW's prestressed wire products.

PC Wire: [Link to SIW's PC Wire product page] (https://www.siw.co.th/en/product-detail/pc-wire)

PC Strand: [Link to SIW's PC Strand product page] (https://www.siw.co.en/th/product-detail/pc-strand)