Abstract: In the past few years,the Voronoi spatial data model has attracted more and more attentions. However,the Voronoi tessellations used in the Voronoi spatial data model are ordinary and the obstacles are not taken into account. Modifying ordinary Voronoi diagram with linear obstacles is one of the two basic approaches in generation Voronoi tessellations with obstacles. The authors proposed to aggregate the segmented linear obstacles for forming united partitions. The algorithms and techniques for modifying the ordinary Voronoi tessellations based on these united partitions are discussed further in this paper. The VORDLL is used in the experimental work.