ABSTRACT
Settlement control has been always the main concern during shield tunnelling construction, especially in earth pressure balanced (EPB) shield tunnelling construction. However, owing to the lack of efficient real-time sensing methods of excavated material, settlement even sinkholes occasionally occurred in urban areas. Therefore, a near real-time sensing technology of excavated material in EPB shield was designed and developed with the weighing cells installed on the bottom of the muck cars, which solved the problem of data transmission due to the muck car moving by the means of wireless communication. The filed results in Nanning metro indicate that the measured error is less than 5% compared with the gantry crane weighing results and it is beneficial for the engineers to have a knowledge of the excavated material in real-time to make better decision for steering tunnelling parameters to control settlement.
