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Design 1 is primarily constructed from vacuum formed high-density polyethylene (HDPE) and steel rebar. The main structural support for the design comes from the rebar, which forms a grid similar to two pound signs (#) that rest on top of each other. The rebar extends beyond the edges of the plastic and digs into the ground after the design is installed on location, which helps to provide stability and prevent movement while in use. Additionally, during assembly the device is inset slightly into the ground so that the outer perimeter flange of the plastic and the rebar are covered by a thin layer of dirt. The HDPE is vacuum formed to create recesses for the rebar to nest inside of, and to create ribbing to increase the load distribution. A second, flat, piece of HDPE rests on top of the vacuum formed section to provide a flat surface to stand on, aid with load distribution, and increase the strength of the device. There is also another section of HDPE which serves to cover the opening hole in the device when not in use. The entire device weighs 22.2lbs when assembled and is designed to support 270lbs.
Design 2 is constructed from plastic lumber boards made from 100% recycled HDPE. The design has thinner sections of HDPE which lay next to each other to form the top surface to stand on. This is supported by several thicker cross-member sections of HDPE under the top surface that run perpendicular to the top boards. The inspiration for the design was based on the standard design layout for most common household decks and patios. The design is slightly inset into the ground to provide stability and prevent movement while in use. Also, there is an additional piece of HDPE to cover the opening to the hole below while the device is not in use. The entire device weighs 22.9lbs when assembled and is designed to support 270lbs.