Centrifuge Model Test On Ground Settlement Control During Tunnel Excavation In Stratum With Abundant Water

Centrifuge model test is a technique that is widely used in the research field of Civil Engineering. One of its most distinct advantages is that the process of deforming and being destroyed of the soil can be observed with prototype. At first, this thesis summarizes the developing history and the state-of-the-art in centrifuge model test and discusses the principle of the technique of the centrifuge model test. To discuss the feasibility of applying this technique into the practice of engineering, this paper references the real project of the running tunnel from Great Showplace to Scientific House in Shenzhen Metro, uses the geotechnical centrifuge of Southwest Jiaotong University, then researches the settlement of the ground and the influence on the pipeline underground in stratum with abundant water by the technique of undraining spin-spay pile, at last draws a conclusion about the principle of the ground settlement with the construction method of excavating soil rich in water without dewatering at Shenzhen Metro. The result is satisfying comparing to the simulation of ANSYS5.6 and the data from the field. Centrifuge model test technique preferably solves two problems: one is the gravity loss of the model soil, the other is the coupling problem between the seepage field of the ground water and the stress field of the stratum, which is a guidance for other deformation controls under the similar condition. On the puzzle of dynamic simulation of tunnel excavation with centrifuge model, this thesis makes a trial research on the section of SK3+395 of Shenzhen Metro and has made some progress. At last, this thesis points out some problems existing in the centrifuge model test technique and estimates the developing trend of this technique.