Experimental Study on the Complex Contact Frictional Property of an Ultralong Distance Large-Section Concrete Pipe Jacking and Prediction of Pipe String Stuck

Table 2

Specifications and technical parameters of the rock shear rheometer.

Model			The rock shear rheometer
Direction of force			Axial (vertical)	Tangential (horizontal)
Test force		Maximum test force (kN)	600	600
		Relative error of indication (%)	Better than ±0.5
		Effective measurement range	1–100
		Test force control stability	≤ ±1% indication
		Test force resolution (1/code)	1/300000 (1 resolution over full range)
		Minimum resolution (N)	10	10
Displacement		Stroke (mm)	100
		Measurement and control range (mm)	0∼100
		Indication error	±0.5
		Displacement resolution	0.001 mm
Deformation		Maximum measuring range (mm)	30
		Measurement range (%FS)	0.4∼100
		Relative error of indication (%FS)	±0.5
		Deformation resolution	0.001 mm
Control parameters		Control mode	Test force, displacement, deformation
		Axial, tangential loading rate (mm/min)	0.1∼100
		Axial, tangential deformation rate (mm/min)	0.001∼10
		Continuous operating time	Greater than 1,000 hours