Introduction and Implementation of Virtual Borehole in the Construction of Urban 3D Strata Model

Engineering borehole data is the primary data source for the reconstruction of urban 3D strata model.For a given study area,sometimes it is impossible to construct an integrated,accurate 3D model based on limited sample data obtained from boreholes,which are usually sparse and scattered.To solve this problem,a conceptual model called virtual borehole is presented.In the process of modeling,several virtual boreholes can be acceded to the 3D strata model on the proper position for the user's demand and comprehension of the geologic model.Virtual boreholes restrict the model just as actual boreholes,and then generate a 3D solid strata model which is accurate and subtle.A case study is presented to compare the practical effects of using and not using virtual borehole.The result shows that it is flexible,visual and operable of using virtual borehole in the 3D strata modeling.