patent references
Overview of TBM
Construction method
efficency comparison
engineering Construction method
 
동양산업
Vc = π/8 × D¼ x λ x pe(㎥/ea)
L = Vc x n/A (m/ea)
In here, Vc:Digging volume per 1DISC RING(㎡)
D:Digging diameter
λ:Lifecycle of DISC RING (Rolling distance, 500km)
L:TBM drilling distance per DISC RING(m)
A:Digging cross section(㎥)
n:Number of mounted cutter(except center cutter)

■ Calculation criteria for cutter exhaustive volume(DISC RING)

Item
Service hours
exhaustion basis
Remark
OUTER & GAUGE CUTTER
DISC RING & RETAINER RING
200
1
 
MAIN BODY
400
1/2
 
BEARING & THREADED RING
600
1/3
 
CENTER CUTTER
300
1/1.5
 
SCRAPER
200
1
 
BUCKET
400
1/2
 
OTHER
5%
 

■ Pe Value by compressive strength according to construction history(current add-up basis)

Item
Compressive strength(Daily compressive strength:kg/㎠)
Normal
remark
Range
Application
Very hard
1,500
0.23~0.27
0.25
 
Hard rock
1,300~1,500
0.27~0.32
0.30
 
Medium rock
1,000~1,300
0.32~0.38
0.35
 
Soft rock
700~1,000
0.37~0.42
0.40
 
Weathered rock
500~700
0.42~0.47
0.45
 
(Explanation) Internally used standards hr=0.3 default valve
Remark) hr:Coefficient according to the diameter of DISC RING., (12"~15")=hr:0.2~0.3, 151/2"More than hr:0.4~0.5
■ Theortical Pe value by the equipment specification

 Pe by compressive force In here, Pe:Penetration depth
 Pe by rolling force Fc:Compressive force
Fr:Rolling force
σ : Rock compressive strength
B : DISC RING edge angle
d : DISC RING diameter