Quantitative Evaluation of the Adaptability of the Shield Machine Based on the Analytic Hierarchy Process (AHP) and Fuzzy Analytic Hierarchy Process (FAHP)

Table 3

Primary evaluation indices.

Target layer	Rule layer	Scheme layer
Evaluation method of shield-type selection (T)	Geological conditions (C1)	Stratigraphic characteristics (u11)
		Distribution of groundwater (u12)
		Distribution of harmful gases (u13)
		Bad geology and geological disasters (u14)
		Specific rock and soil (u15)
	Environmental conditions (C2)	Existing building (u21)
		Underground pipelines (u22)
		Existing urban rail transit and railways (u23)
		Surface water body (u24)
		Urban planning land (u25)
		Vibration and noise (u26)
		Ground traffic (u27)
		Disposal of sludge and soil (u28)
	Shield construction (C3)	Propulsion speed (u31)
		Rotation speed of the cutter head (u32)
		Grouting pressure (u33)
		Soil pressure (u34)
	Design of shield machine (C4)	Total thrust (u41)
		Main drive torque (u42)
		Grouting ability (u43)
		Number of muck improvement openings (u44)
		Type of cutting tools (u45)
		Slagging quantity of screw conveyor (u46)
		Spacing design of cutting tool (u47)