Expansion joints also referred to as movement joints mimic such parts in our bodies as they expand and contract as needed. These movements contribute to a structure’s overall stability. They work in bisecting a structure, like a building, and creating a gap. The gap is then filled to restore the building and to double its ability to withstand physical traumas. They are also used on construction sites to counteract seismic activity as well as help secure the structure while other parts are built around it. They protect against strong winds, dangerous temperatures, and other physical occurrences that could affect the strength of a building and its durability.

Changes in temperature, such as extreme heat, causes the materials in a building to expand and these joints counteract this expansion by contracting. Doing so restores equilibrium by re-compressing the materials within a gap to their original size. When temperatures drop below freezing building materials can constrict. The expansion then forces these materials to re-expand.

The ability of expansion joints to widen and narrow regulates structures’ gap sizes, thus reducing the need for repairs and other maintenance procedures. Side-walks, bridges, railways, and many buildings use them for their stress-relieving qualities. Large air ducts use them to regulate changes in temperature. They are also found in pipes, where they help stabilize movements between separate parts of a structure.

Joint Placement or location varies depending on the structure. In some instances, joints are located in the middle of the project. This is the case with bridges and pipes. Other structures need several throughout. On train tracks, for instance, they can be found every 60 feet or so for temperature regulation purposes. Most are placed at strategic points of strain and pressure in a structure. Ultimately, it is important to choose areas that will need to absorb the most pressure.

Joint and Structure Materials are usually made of metal, such as stainless steel, this material allows for a restricted range of motion within a structure, while keeping it intact and under control.

Other materials include rubber expansion joints made from rubber and those made of concrete.

To avoid gaps that could result in cracking of the concrete or increase chances of structural damage and lack of efficiency on the joint material, the size of the joint should be determined well in advance and the entire set-up should be packed very closely. You cannot afford to leave gaps.

The expansion joint material should be elastic. However, you should not restrict yourself to rubber, foam or other such substances. Remember, the gap or jointly provided does not exceed more than an inch in case of very big structures. Regardless of what material is being used, joints should be placed in between portions of several structures for added support as they are malleable and adaptive.

The Expansion joints have revolutionized the way that many structures are built today. They reduce repair and maintenance costs, thus allowing for a greater diversity of structures to be built. They have proven to have useful qualities that can withstand the many negative effects that weather and other forces of nature pose to a building’s overall safety and stability.