Application Research Of Simulation Deep Foundation Pit Dewatering Using Three Dimensional Stratum Modeling

In recent years, with China’s sustained economic development, the city infrastructure construction is greatly boosted; in general, geographic location of the infrastructure is distributed in Quaternary sediments. These sediments are formed in a close year, and have a variety of forms and come from a variety of species. To study the layer, under normal circumstance, Engineering Survey Department may submit topographic data, hole drilling data, trench and tunnel and other data, and these data is preserved in the form of text, chart, and drawing. They are poor to describe the formation of spatial geological tectonic change and often fail to reveal the formation of spatial variation. The three-dimensional models can express the boundary conditions of geological formation and geological body covered by geological structure completely and accurately. And they can display three-dimension realistically, develop the immediacy and accuracy of geological analysis, and make the engineering design and construction project in accordance with the actual geological phenomenon based on three-dimensional models.This thesis intend to build the three-dimensional models of expansive soil in Chengdu plain and the central shoal in the upper reaches of Minjiang River using GMS software, and the layers of the study areas can be clearly showed through the models. It can provide a good reference to build the three-dimensional models for the complex Quaternary sedimentary strata area, and use this model the groundwater in the deep pit can be studied. This thesis has made the following achievements:Firstly, in the expansive soil region of Chengdu Plain, three-dimensional models were built. The data was obtained and the profiles were generated and revised. On the basis of these operations, the three-dimensional models were built, and the interpolation methods were discussed. Compare the models, the relative error of the terrace area II using Inverse Distance Weighted was less than the method of Natural neighborhood interpolation.Secondly, in the upper middle area of Minjiang River, three-dimensional models were built. After comparing the models, IDW and natural field interpolation methods in the terrace area I were of mall difference.Thirdly, based on these models, a variety of layers were three-dimensional displayed and queried. And on the basis, the properties such as volume could also be displayed. This can be a good reference for the later researches.Fourthly, the layer on the study area can be cut arbitrarily; and the use of virtual drillings can provide an excellent method for the area with little data.Finally, using different interpolation methods, the models of the deposit area built by Inverse Distance Weighted interpolation method were better than the Natural neighborhood interpolation.