Measurement and Analysis of Settlement Induced by Rectangular Pipe Jacking in Silt Stratum

Table 3

Surface settlement monitoring.

Items	Instruments	Number of Measured point	Frequency
Settlement	Optical level	63	The distance between the pipe jacking head and the monitoring section is 20 m, 1 times/d.
			The cutter head is 15 m away from the monitoring section, 1∼2 times/d.
			After the cutter head passes through the monitoring section, it is continuously monitored until the trend is stable, 1 times/d.