The present disclosure provides a movable load bearing structure having a light weight core covered with at least one polymeric sheet for improving its loading bearing strength. The movable load bearing structure includes indentations, grooves, valleys, channels or other similar depressions on its underside. These depressions are mated with corresponding features for improved loading bearing capabilities. The load bearing structures also includes roughened side edges for improving the strength of the edges. The movable structure may be in the form of a dunnage platform or a container for storing and/or shipping cargo.