| 摘要 |
PROBLEM TO BE SOLVED: To enable judgement of the strength of rock and property of ground, including cracks accurately by setting the range of excavation energy values corresponding to the kinds of ground property, and obtaining excavation energy to judge the ground property. SOLUTION: The relation between the grade of ground and excavation energy of a tunnel boring machine is obtained by providing a trial excavation section of a planned tunnel line. Raw excavation data are collected, boring data are computed, and then boring energy is computed. In parallel thereto, the grade of ground is determined from face observation, hammer sounding and the property of a boring core. The cumulative distribution of excavation energy is obtained from the result of trial excavation, and the grade of ground is determined. In the procedure from the sampling of raw excavation data to the determination of the grade of ground, if it is taken on every occasion of sampling, determination can be done within real time, the selection of a timbering pattern can be accelerated and the trouble such as the binding of a tunnel boring machine in a soft portion of the ground can be avoided. |
