ABSTRACT
There have been developed a lot of methods which are quite useful for the excavation of tunnels in various types of ground conditions. A typical one is the so-called NATM for the mountainous tunnels where shotcreting and rockbolting are considered to be the main support against the earth pressure around tunnels. It is, however, noted that no understandable theories for it are found out to explain the performance of the interaction between the tunnel and the surrounding ground from the view point of applied mechanics. A trial will be made in this report to investigate the fundamental mechanism of the mountainous tunnel excavation by considering results of simple experiments and numerical calculation.
