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The integration of 2D GIS and 3D GIS is an important application of the current virtual city system. This paper constructs a virtual city system that integrates 2D GIS and 3D GIS. On this basis, research and achieve on visualization interactive of 2D GIS and 3D GIS. The interactive algorithm is proposed based on the assumption of parameters, so the viewpoint position of the 3D scene can be located according to the 2D scene viewpoint parameters, the viewpoint position of 2D scene can be located according to the 3D scene viewpoint parameters as well, and the position synchronization is maintained in both views through event trigger mechanism during interaction. When user manipulates one viewpoint in 2D GIS or 3D GIS, the others moves synchronously to the same area and angle. Three different views are used as contrasts to verify the accuracy of the algorithm. The implementation results show that the algorithm of synchronization can adapt to various user operations, with feasibility and accuracy.

A new test method using moisture rate to represent workability indicators of dry-hard mixture is introduced in order to test the control indicators of VC value in the construction of roller compacted concrete rapidly. In view of the complexity of the impact of proportional difference on VC value and moisture rate, this paper carries out field tests of roller compacted concrete in Guoduo hydropower station of Tibet. A simplified linear quantitative model formula of VC value and moisture rate at the construction site is established based on determined aggregate grading, admixture, additive type and the amount of admixture of roller compacted concrete mixture, providing conditions for the rapid and accurate measurement of construction quality indicators of roller compacted concrete.