Above ground swimming pools vary slightly from model to model, but you will find that most manufacturers use the same general pool structure.
The wall is most typically made of galvanized steel. For round and oval pools, the wall is usually all one piece. The wall is corrugated for strength and then coated in vinyl and/or a number of other coatings to help protect it and give it a more attractive appearance. Usually, the more layers there are over the steel; the longer the wall can last.
The strength and durability of the wall defines the integrity of the pool structure. It must safely contain up to 200,000 pounds of water weight for the life of the pool.
The steel walls are shipped in coiled rolls, usually tightly bound and boxed in cardboard. Walls should be stood up on end until they are installed.
The uprights, or posts provide support for the wall and top frame of the pool. Uprights can range up to 12" wide depending on the pool model and the material they are made of.
You will find a top plate attached to the top of each upright. They provide connection points for the top track and top rails that span between each post.
The base plates sit beneath each upright, providing a connection point for the base track and the upright itself.
Usually made of resin or other form of plastic, the top cap covers the top plate and help to give the pool a more finished, attractive look.
Some pools have plastic or resin boots at the bottom of each upright that, like top caps, cover up the base plate and are mainly aesthetic.
The inside surface of the swimming pool is covered by a vinyl liner that contains the water within the structure. Liners are designed to fit specific sized pools.
As your pool ages, the liner may eventually need to be replaced. Patch kits can be used to prolong the life of the liner. Typically, you can expect a liner to last five to ten years.