During the construction of large scale geotechnical projects

tunnels and cavern groups are of the common underground structures. In recent years

the technologies of GIS and virtual reality have become very attractive in this research field. However

due to the effect of complex in situ geological condition and spatial modelling algorithms

it is still a difficult and important subject for three-dimensional synthetic model building and visualization analysis toward strata and cavern. A new technique to build stratigraphic model is discussed based on three-dimensional grid data

it results in an adaptive algorithm to build strata model by multi-DEM(digital elevation models). Furthermore

the main subject of this paper related to simulation of three cavern excavated based on three-dimensional strata modeling is systematically discussed; through a series of complex algorithms such as three-dimensional entity model of cavern

subtraction of cavern and stratigraphic skirt

intersection between cavern and strata

the three-dimensional model of cavern including strata information is built finally. A typical case in relevant to a hydropower station is given at the end of this paper.