A method for stabilizing a grain mound covering tarp including steps of assembling a matrix of flexible tubes over the tarp and filling the matrix of flexible tubes with water； wherein the matrix assembling step provides a multiplicity of collapsible tubes forming a quadrilateral grid； wherein the matrix assembling step further provides a plurality of T joints and a plurality of + joints interconnecting the collapsible tubes； wherein the collapsible tube providing steps include a pair of cam connector halves attached to the ends of each collapsible tube； wherein the T joint providing steps include a triple of cam connector halves attached to each T joint； and wherein the + joint providing steps include a quadruple of cam connector halves attached to each + joint.
