The 1200 standard block is the foundation of the Interbloc precast wall system. It is placed in a running bond pattern, meaning that each layer overlaps the one below it. This pattern ensures that the shear key, a protrusion on the side of the block, is fully engaged, providing maximum strength and stability to the wall. The 1200 standard block is typically used in 80-90% of any Interbloc wall structure.

• The running bond pattern is a common way to lay bricks or blocks. In this pattern, the blocks are staggered so that each layer overlaps the one below it. This creates a strong bond between the layers and helps to prevent the wall from collapsing.
  
  
• The shear key is a protrusion on the side of the block that helps to interlock the blocks together. When the blocks are placed in a running bond pattern, the shear keys engage with each other, creating a strong bond that resists forces trying to separate the blocks.

Flat bottom blocks are commonly used for the bottom layer of a wall. They can serve two purposes:

• Increase friction and sliding resistance between the ground and the structure. This is done by providing a flat surface that makes it more difficult for the wall to move.
• Provide a physical barrier to leachate and prevent cross-contamination between structures. Leachate is a liquid that can seep through the ground and carry contaminants. A sealant is often applied to the flat bottom blocks before they are placed to prevent leachate from reaching the wall.

A Top block is primarily used for two purposes:

• To prevent the accumulation of material on top of a wall: This is especially important in bulk storage areas, where materials such as grain or aggregate can build up and create a hazard. The top block provides a pointed, smooth surface that prevents material from accumulating at the top of a bin.
• As a traffic delineation barrier: Top blocks can be used to mark the edges of walkways, parking areas, and other traffic areas. This helps to prevent accidents and keep people safe.
  
  Both of these purposes serve important health and safety functions. By preventing the accumulation of material on top of a wall and delineating traffic areas, top blocks can help to prevent injuries and property damage.
  
  

The 1800 flat top block is used in conjunction with the 1200 flat top block at the top of a wall to create a flush finish and to facilitate the attachment of a roof structure to the top of the wall.

The 1800 standard block is primarily used for two purposes:

• To join a dividing wall of a bulk storage bin into a back wall.  This is done by placing the 1800 block on every alternating layer, starting at the corner of the bin. This ensures all blocks are interlocked and the wall is structurally sound.
• To start or finish a running bond pattern. The blocks are staggered so that each layer overlaps the one below it. The 1800 block is used on every alternating layer at the start or end of the pattern to create a flush end to the wall.

The 1800 flat bottom block and the 1200 flat bottom block are used together on the base row of a wall to create a seamless finish between the structure and the underlying foundation. This can help to:

• Prevent leachate flow: When used with a sealant, the flat bottom blocks create a physical barrier that can help to prevent leachate from flowing under the wall.
• Increase friction between the wall and the foundation: The flat bottom blocks provide a larger surface area for friction to develop, which can help to prevent the wall from sliding. 

A 1200 base block is typically used on the base row of a wall, especially in bulk storage applications. This is because the base block has a wider footprint than a standard block, which helps to spread the weight of the wall over a larger area. This is important in bulk storage applications where the wall may be subjected to heavy loads.

The base block is also used in situations where a new structure is being built on an existing concrete foundation that would not otherwise be able to support a block wall. The base block helps to distribute the weight of the wall more evenly over the foundation, reducing the risk of the foundation sinking or cracking.