Patent attributes
Self-raising drive-over entranceways for containment berms are disclosed. The entranceway includes a horizontal bottom panel and a collapsible sidewall that is held in a partially collapsed position forming a void between the bottom panel and sidewall. During a spill or the filling of the containment berm with a fluid, the void area between the partially collapsed sidewall and the horizontal bottom panel fills with the fluid and exerts hydrostatic pressure against the partially collapsed sidewall, forcing it to rotate upward. The higher the fluid level, the more hydrostatic pressure is applied against the sidewall, forcing it up higher until the sidewall obtains a vertical orientation. The sidewall may be restrained either by straps, braces or the like to prevent the fluid from escaping the containment area.
