The Application Of Subsoil Improved By Low Vacuum Preloading

In order to improve the design and the construction, improve construction quality, reduce construction difficulty and costs, the application research of the low vacuum preloading method is going on.In this paper, the design and construction problems and solutions of the vacuum preloading method in low level position are stated, the effect of consolidation of soft soil foundation by using this method is described through specific projects on the basis of analyzing theory of consolidation. Before construction, a small short-term consolidation experiment on the foundation layer should be done, it will get the consolidation process and the character of the foundation layer, the consolidation parameters of the foundation layer is gained by backward pass according to the results of the experiment, which will amend the design, and guarantee the consolidation effect effectively, at the same time, the research on the character and consolidation process of the hydraulic air-proof layer will ensure the vacuum consolidation process smoothly. The automation control system of vacuum pumping and drainage is gained on the research of water-gas separation technology, it is nimble, accurate and less manpower. The water level indicator is simple, affordable, robust, stable and reliable, and it is easy to adjust. The combination of a solenoid valve and a one-way stop return valve guarantees the well-function of pumps, no gas flow sucking in and the vacuum state of the vacuum system is ensured. The SKA5111 water ring vacuum pump is used to replace the W-3 vacuum pump, the limit vacuum and exhaust volume of the SKA5111 water ring vacuum pump are equal to W-3 vacuum pump, and it is easy in transportation, installation and maintenance, it is greatly inexpensive and it is greatly decreased the environmental pollution. The monitoring data is easily analyzed by using the experiential method, the project construction can be effectively guided.