Corrugated Paper Materials Provide Performance Reliability
When properly used and protected from premature moisture absorption, these offer the greatest loss of strength that is needed to ensure complete structural breakdown after the concrete is placed.
Careful planning and jobsite preparation must be considered when utilizing these types, since they are susceptible to precipitation and moisture in the air and surrounding soil.
Plastic materials are the best alternative if extreme water is prevalent
If extreme water is prevalent or in inclement weather, it becomes difficult to utilize materials that absorb moisture to properly function by design. Thin, flexible plastic components that are impervious to water become the best option.
EPS Foam materials must be properly designed
Although frequently used to mitigate damage caused by frost heaving or soil expansion, solid blocks of EPS foam do not provide a sufficient cushion to allow for significant uplift. Foam-based materials increase resistance as they compress, transferring energy into the structure above. They must be engineered having the majority of the material removed to create void cavities between support elements.