(I)-TM: I-System’s Tunnelling Method – An Introduction

The paper presents an introduction to (I)-TM as I-System’s tunnelling method. (I)-TM is explained in detail including its compatibility with design procedure, application, concept, features, and utilisation. It is a hybrid tunnelling method that combines classification, characterisation, as well as tunnelling method all together, which is applicable for any medium under any condition from pre-design to post-construction phases. Its concept assumes a lifetime structure in design and construction with comprehensive applicability for any medium under any condition taking into consideration the load-bearing capacity of surrounding ground and active pre-/post-excavation primary supports as part of final measures. It is based on full usage of I-System for underground structures for classification, characterisation, determination of ground zoning, identification of ground behaviour, diagnosis of the associated ground hazards, determination of support systems, structural dimensioning, and structural verification of the dimensioned structure as well as post-excavation damage assessment. (I)-TM follows the outputs and recommendations of I-System’s classification and characterisation, which are called (I)-Class and (I)-GC. (I)-TM proposes suitable excavation technique/s in tunnelling with safe pull length, active support system configuration for optimised stability, efficient instrumentation technique for monitoring, intelligent prevention technique/s for avoiding and controlling the hazards, and high-performance forecasting technique/s for prediction of ground ahead of the face for a safe and optimised advance in a tunnel or any other underground spaces. Its applicability and performance in design and construction is already examined during I-System’s 22 years term of development and 3 years post-development in practice.