Ama-Tunnel Boring Machines (ama-TBMs) asebe yitshe legumbi lobunjiniyela besimanje, ikakhulukazi endaweni yengqalasizinda yomphakathi. Le mishini ekhethekile yenzelwe ukumba imigudu ngezinhlobo ezahlukahlukene zenhlabathi namadwala, ukubenza babalulekile kumaphrojekthi afana nezinhlelo zomgwaqo ongaphansi komhlaba, imigudu yomgwaqo, nokufakwa kwezinsiza. Ukuthuthukiswa kwama-TBM kuthuthukise kakhulu ukusebenza kahle kanye nesa