Written by Matthew Kuester and Bill Handlos, PE An accurate understanding of creep resistance is essential to proper material selection when using polymers, and in the case of geocells, this science is being misapplied.  The definition of creep deformation is the tendency of a solid material to move slowly or deform permanently under the influence of mechanical stress.  Creep is something that creates fear and uncertainty with all designers where the possibility of creep factors exist. Yes, creep can occur in almost all materials including plastics, metals and concrete.  In cases such as bridge and building design, it is important to properly understand creep factors and account for creep in engineering calculations.  Yet, in the case of designing with geocells for load support, creep factors have no relevance. What Causes Creep? In order for creep to occur there must be; a constant load applied and a sustained deformation.  Creep only applies when there is a sustained load on a material for an extended period.  In a case of repeated on and off loading, this would be governed by fatigue and not by creep.  The second required factor for creep to occur is an ability to undergo sustained deformation of the… Read more »