Easement spatialization with two cases based on BIM

An Easement is a kind of usufructuary right, and its main purpose is that one party wants to use the property of others to improve the benefits and interests of his own real estate. With increasing population and accelerating urbanization, the limitation of urban space has gradually become prominent problem. To use the spatial resources fully, urban planners have focused on the development and utilization of three-dimensional urban space, namely, underground, ground and aboveground vertical space. The traditional 2D cadastre only using floor plans cannot meet the current 3D cadastre management needs. Therefore, the jurisprudence-confined planar easement must be combined with spatial information from 2D to 3D, as well as the 2D cadastre bounds to be extended to 3D to adapt to urban development. This study focuses on the property owner in 3D cadastre, therefore "easement of access" is chosen as the key topic, which is the right to cross the property to go to and from another. The conceptual models of easement spatialization based on building models of IFC (Industry Foundation Class) standards are constructed and analyzed. This study takes the condominium as an example, which displays how to access the semantic information associated with the geometric information of 3D property object in BIM (Building Information Model). Besides, the servant and the dominator of the easement are able to be linked because they are both attached to the same physical space. The research result shows that BIM can optimize the complex presentation of 3D property attributes and is an effective carrier of easement spatialization. The combination of legal information and spatial information of 3D property not only optimizes the operation and maintenance of buildings, but also improves land management, accelerates the development of 3D cities; thereby these will enlarge effective urban space, improve its utilization efficiency, and help resolve the contradiction between the rapidly expanding urban population and the limited shortage of space resources.