Construction tubes, or construction cores, are cardboard tubes used to help form and create concrete construction components. Most commonly these products are utilized to fabricate concrete columns for load bearing applications but can be used for many other industrial and commercial applications.
Construction tubes provide construction workers with a simple and effective method for shaping and containing concrete. In order to create concrete components or structures, the liquid concrete has to be poured into a mold and allowed to set and cure. The curing process is a fairly slow process and typically takes a full day to complete. Construction cores are designed and manufactured to specifically bear the pressure of the liquid concrete, so that the concrete is properly contained for the full duration of the curing process. Once the concrete has cured, the tube can be left in place or it can be removed, depending on the application requirements. Construction tubes are used to create columns for highway support as well as piles for foundation applications. In foundation applications, construction cores can be used to create concrete piles without the need for a pile driver. While these tubes are commonly used for large construction projects, they can also be used for smaller commercial applications. They are used in many home improvement projects like post-setting applications.
Manufacturers typically manufacture construction tubes using spiral wound fiber layers. Tubes are manufactured in many different sizes to accommodate many different construction applications. The most important dimensions to consider when choosing a construction core are the diameter and thickness of the tube. Tube diameter determines the thickness of the concrete component, and the tube thickness determines the strength of the construction tube. For example, when creating a large concrete column, you would most likely require a thicker tube with a large diameter. Greater thickness allows the tube to bear the greater load and pressure of the increased quantity of liquid concrete within the tube. Tube length is another dimension to consider but is much easier to manipulate. Since these tubes are constructed from cardboard, they can be cut to the desired length with common hand or power tools. Construction tubes are also fabricated to meet the unique chemical requirements of concrete. Water is a fundamental component of the concrete mixture and curing process. However, in many circumstances, the surrounding soil or air can pull the water out of the concrete as it cures. This drastically reduces the strength of the concrete. For this reason, many construction tube manufacturers incorporate a water resistant lining, like wax, into the tube design to help hold in the water, resulting in improved concrete strength.