Abstract
The authors had carried out some kinds of trapdoor experiments and had discussed in detail the mechanical behavior of the ground during tunnel excavation. In this research, three dimensional trapdoor experiments and its numerical analyses were carried out with various overburdens for the purpose of investigating in detail and quantitatively the earth pressure characteristic and the deformation characteristic during tunnel excavation. Validities of analyses are inspected by comparing the analytical results with experimental ones. Moreover, Terzaghi's earth pressure theory and Arching theory are applied to the trapdoor experiments, and their applications are discussed comparing with experimental results and analytical ones.
