Performance Evaluation of Hard Rock TBMs considering Operational and Rock Conditions

Abstract

This paper focuses on studying the correlations of the performance of hard rock tunnel boring machines (TBMs) with operational and rock conditions. Firstly, a rigid-flexible coupled multibody dynamic model of an opening hard rock TBM is established for the analysis of its vibration. Then four performance indexes including mean vibration energy dissipation rate, dynamic specific energy (DSE), disc cutter wear rate, and load sharing coefficient are introduced and formulated, respectively, for evaluating the vibration level, excavation energy efficiency, cutter’s vulnerability to wear, and load transmission performance of cutterhead driving system of the TBM. Finally, numerical simulation results of the TBM tunneling performance evaluation are obtained and validated by on-site vibration measurement and tunneling data collection. It is found that operational and rock conditions exert important impact on TBM vibration level, excavation energy efficiency, and structure damage. When the type of rock to be cut changes from soft to hard with operational parameters held constant, TBM performance evaluated by these three indexes deteriorates significantly, and both the decrease of excavation energy efficiency and the increase of cutter wear rate caused by TBM vibration are obvious. This study provides the foundation for a more comprehensive evaluation of TBM performance in actual tunneling process.

A Rock Fracturing Method Using High‐Pressure Gas Expansion: Case Study on Its Application in Hangzhou‐Lin’an Intercity Railway

“…With the construction of urban subways and the increased density of subway line network, the construction of urban underground tunnels will inevitably pass through hard strata. Tunnel Boring Machine (TBM) and shield method are usually applied in the main tunnels of an urban subway with hard rock strata, but there are some limitations in their size when excavating the subway connecting passage [1][2][3]. Mining method is often used in excavating the connecting passage of an urban subway, but the construction process with the mining method impacts the environment and safety near the blasting region.…”

Nonlinear Static and Dynamic Stiffness Characteristics of Support Hydraulic System of TBM

“…The system vibrations generate noise, harm workers' health, and may damage key components of the system [3][4][5][6]. The vibration energy is transferred to the support system through the main beam, making the support system vibrate [7]. As a key working component of TBM, the support system provides the excavating counter-torque and counter-force during the excavation process [8,9], which has an important influence on system vibration; therefore, the stiffness characteristics of the support system receive significant concern [10,11].…”

A New Evaluation Method for the Uniaxial Compressive Strength ahead of the Tunnel Face Based on the Driving Data and Specification Parameters of TBM

“…Encouraged by the opening of Japan's Sei-kan tunnel (50.5 km in length) and the British-French submarine tunnel (53.9 km in length), a large number of larger scheme extralong tunnels have been planned in China and abroad, for example, the Japanese-Korean submarine tunnel between Fukuoka and Busan (250.0 km), Gotthard railway tunnel in Switzerland (56.9 km), and the Basis Brenner railway tunnel between Austria and Italy (55.0 km). Compared with traditional techniques such as drilling and blasting, the fullface rock tunnel boring machine (TBM) has gradually become the first choice for long and deep tunnel construction in recent years since it has many advantages, such as high quality, high efficiency, environmental protection, and small disturbance of surrounding rock [1,2]. As one of the most fundamental mechanical parameters, UCS has widely been applied in the process of TBM construction including assessment of rockmass rating (RMR) and Q TBM rockmass system, hazard assessment of rockburst classification or TBM jamming and assessment of the reasonable supporting design [3][4][5][6].…”