naruki wakabayashi shimizu corporation tokyo japan
DESCRIPTION
Study on the Jointed Rock Mass for the Excavation of Hyper-KAMIOKANDE Cavern at Kamioka Mine. Naruki Wakabayashi Shimizu Corporation Tokyo Japan. NNN07 Hamamatsu, Japan 3-5 October 2007. Topics ・ Previous Geological Survey and Stability Analysis for the Hyper-K cavern - PowerPoint PPT PresentationTRANSCRIPT
11
Naruki WakabayashiShimizu Corporation Tokyo Japan
Study on the Jointed Rock Mass forStudy on the Jointed Rock Mass for the Excavation of Hyper-KAMIOKANDE Cav the Excavation of Hyper-KAMIOKANDE Cav
ern at Kamioka Mineern at Kamioka Mine
NNN07 Hamamatsu, Japan 3-5 October 2007
22
Topics ・ Previous Geological Survey and Stability Analysis for the Hyper-K cavern ・ Site Selection ・ Isotropic Elastic FEM Analysis for the Investigation of Cavern Shape, Size and Type
・ Ongoing Investigation and Analysis for Jointed Rock Mass ・ Investigation of Joint Orientation ・ Obtaining In-Situ Rock Joints and Investigation of Joint Mechanical Properties ・ Pull-out Test of Two Types of Cable Bolt ・ Two Type Analysis to Consider the Influence of Joint and Support System
33
Mozumi mine
Tochibora mine
Proposed Area
Kamioka Mine Location
Kamioka Mine
Hamamatsu
Tokyo
Super-K
Proposed Area in Mozumi Mine is about 10km South from the Super-Kamiokande.
Site Selection
44
Hyper-K Hyper-K proposed Siteproposed Site
HornblendeHornblendeBiotite GneissBiotite Gneiss& Migmatite& Migmatite
Biotite GneissBiotite Gneiss
LimestoneLimestone
”” AN
KO
” Fa
ult
AN
KO
” Fa
ult
”” 240
240
゜゚- M
E” F
au
lt- M
E” F
au
lt
””NAMARI” FaultNAMARI” Fault
Skarn OreSkarn Orebody Zonbody Zonee
Core BoringCore Boring
ExistingExistingTunnelTunnelSurveyedSurveyed
Geological Map of Proposed Siteat Tochibora Mine Plan View of + 550mEL
N
Proposed Site Formation is Hornblende Biotite Gneiss and Migmatite.
100m
55
18m
42m
60m
ƒÓ 60m (r=30m)
Cylindrical Dome Larger than Super-K Huge Tunnel
Comparison of the Hyper-K Cavern from Various View PointsMultipleDomes
Single TunnelTwo Parallel
Tunnels
× ○ ○
△ △ ○
○ × ○
× ○ △
◎ ○ ○
× △ ○ Height 60.0 54.0 54.0 Width Φ 60 48.0 48.0 Length - - - 500 250
3,368 2,076 2,076152,600 1,038,000 519,000
7 1 21,068,200 1,038,000 1,038,000 Total Volume of Caverns (m3)
Size of oneCavern (m)
Cost Performance of Detector Tank
Construction Period & Cost
Cavern Stability
Total Evaluation
Observation during Maintenance
Early Observation Startup
Cavern Type
Vertical Cross Section Area (m2) Volume of one Cavern (m3) Required No. of Caverns
Two Parallel TunnelsIsotropic Elastic FEM Analysis
Image Design of Two 250m Long Parallel Tunnels
Spacing
Spacing
Offset
Offset
””NAMARI” FaultNAMARI” Fault”” AN
KO
” Fau
ltA
NK
O” F
ault
”” 240°-ME
” Fau
lt240°-M
E” F
ault
66
Summary of Previous StudySite Selection : Tochibora Mine, +480mEL~+550m EL is the most appropriate location with very competent rock condition.Cavern Design: Two 250m Long Parallel Tunnels with Section of 2,076m2 are capable of being safely excavated. This Type is possible to continue observation during Maintenance. Cavern Layout : Two Parallel Tunnels as above should be Located with 80m –100m (about 2 Diameter Distance) Spacing and 50m-100m Offset to avoid the poor Zone of Surrounding Faults.
In Isotropic Elastic FEM Analysis of Previous Study, Young’s Modulus was empirically decreased as Jointed Rock Mass.It is Important and Necessary to Consider the Influence of Joint Orientation and Mechanical Properties Numerically.
77
Analysis for Jointed Rock Mass
Anisotropic Young’s Modulus Considering Joint Orientation and Mechanical Properties
Composition of Elastic Blocks Surrounding Joints
Equivalent Continuum Analysis
Discontinuous Analysis
Damage TensorCrack Tensor
Key BlockDistinct Element
Method (DEM)
・ Characteristics of Joint Orientation・ Mechanical Properties of Joint and Rock Core・ Mechanical Properties of Support such as Cable Bolt
88
Investigation of Jointed Rock Mass
B-ⅡB-Ⅰ
B-ⅡB-Ⅲ
B-Ⅳ
D-Ⅴ
C-Ⅳ
C-Ⅲ
B-Ⅱ
B-Ⅲ
B-Ⅲ
B-Ⅱ
B-Ⅲ
B-Ⅲ
B-Ⅲ
B-Ⅲ
B-Ⅲ
B-Ⅲ
C-Ⅲ
B-Ⅲ
B-Ⅳ
C-Ⅳ
B-Ⅰ
B-Ⅰ
B-Ⅱ
B-Ⅱ
B-Ⅰ
B-ⅡB-Ⅰ
B-Ⅱ
B-Ⅰ
B-Ⅱ
B-Ⅱ
B-Ⅱ
B-Ⅱ
B-Ⅱ
B-Ⅲ
B-Ⅲ
D-Ⅳ
B-Ⅱ
C-Ⅳ
B-Ⅲ
B-Ⅱ
B-ⅡB-Ⅲ
B-Ⅲ
B-Ⅱ
B-Ⅱ
B-Ⅲ
C-Ⅳ
B-ⅡB-Ⅲ
B-Ⅱ
B-Ⅱ
B-Ⅲ
B-Ⅲ
B-Ⅱ
B-ⅡB-Ⅲ
B-Ⅲ
B-Ⅳ
B-Ⅳ
-200
+200
- 200
+100
0
-200
- 100
Ap
Ap
Ap
Ap
Ap
Ap
Ap
ApAp
Ap
Ap
Ap
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
70
70
70
75
80
Ao
Ap
Ap
Ap
Ap
Ap
Ap
ApAp
Ap
Ap
ApAp
Ap
Ap
Ap
ApAp
Ap
85
75
80
85
80
80
70
Ap
Ap
Ap
ApAp
Ap
Ap
Ap
ApAp
Ap
Ap
Ap
Ap
Ap
Ap
Ap Ao Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
AoAo
AoAo
AoAo
Ao
AoAo
Ao
Ao
Ao
Ao
Ao
Ap
Ap
Ap
Ap
Ap
Ap
Ap
Ap
Ap
60
S70E
240°目断層
～～～
～～～～
300
220
230
240
250
260
270
280
290
310
320
330
340
350
360
370
380
390
400
210
200
190
140
150
160
170
180
110
120
130
100
90
80
70
60
50
40
30
20
10
0
調査終了点
調査開始点
大規模地下空洞立地可能性調査400m 1:300坑道調査（ ）縮尺
凡例
伊西岩角閃石片麻岩スカルンアプライト緑泥石化片麻岩片理面
割れ目
滴水あり
岩盤分類凡例
B B- B-（ Ⅰ、 Ⅱ）
CH B- C-（ Ⅲ、 Ⅱ）
CM B- C-（ Ⅳ、 Ⅲ）
CL D- C- C-（ Ⅲ、 Ⅳ、 Ⅴ）
D D- D-（ Ⅳ、 Ⅴ）
AP
Ao
巻末資料３岩盤分類図
B-ⅡB-Ⅰ
B-ⅡB-Ⅲ
B-Ⅳ
D-Ⅴ
C-Ⅳ
C-Ⅲ
B-Ⅱ
B-Ⅲ
B-Ⅲ
B-Ⅱ
B-Ⅲ
B-Ⅲ
B-Ⅲ
B-Ⅲ
B-Ⅲ
B-Ⅲ
C-Ⅲ
B-Ⅲ
B-Ⅳ
C-Ⅳ
B-Ⅰ
B-Ⅰ
B-Ⅱ
B-Ⅱ
B-Ⅰ
B-ⅡB-Ⅰ
B-Ⅱ
B-Ⅰ
B-Ⅱ
B-Ⅱ
B-Ⅱ
B-Ⅱ
B-Ⅱ
B-Ⅲ
B-Ⅲ
D-Ⅳ
B-Ⅱ
C-Ⅳ
B-Ⅲ
B-Ⅱ
B-ⅡB-Ⅲ
B-Ⅲ
B-Ⅱ
B-Ⅱ
B-Ⅲ
C-Ⅳ
B-ⅡB-Ⅲ
B-Ⅱ
B-Ⅱ
B-Ⅲ
B-Ⅲ
B-Ⅱ
B-ⅡB-Ⅲ
B-Ⅲ
B-Ⅳ
B-Ⅳ
-200
+200
- 200
+100
0
-200
- 100
Ap
Ap
Ap
Ap
Ap
Ap
Ap
ApAp
Ap
Ap
Ap
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
70
70
70
75
80
Ao
Ap
Ap
Ap
Ap
Ap
Ap
ApAp
Ap
Ap
ApAp
Ap
Ap
Ap
ApAp
Ap
85
75
80
85
80
80
70
Ap
Ap
Ap
ApAp
Ap
Ap
Ap
ApAp
Ap
Ap
Ap
Ap
Ap
Ap
Ap Ao Ao
Ao
Ao
Ao
Ao
Ao
Ao
Ao
AoAo
AoAo
AoAo
Ao
AoAo
Ao
Ao
Ao
Ao
Ao
Ap
Ap
Ap
Ap
Ap
Ap
Ap
Ap
Ap
60
S70E
240°目断層
～～
～～
～～～
300
220
230
240
250
260
270
280
290
310
320
330
340
350
360
370
380
390
400
210
200
190
140
150
160
170
180
110
120
130
100
90
80
70
60
50
40
30
20
10
0
調査終了点
調査開始点
大規模地下空洞立地可能性調査400m 1:300坑道調査（ ）縮尺
凡例
伊西岩角閃石片麻岩スカルンアプライト緑泥石化片麻岩片理面
割れ目
滴水あり
岩盤分類凡例
B B- B-（ Ⅰ、 Ⅱ）
CH B- C-（ Ⅲ、 Ⅱ）
CM B- C-（ Ⅳ、 Ⅲ）
CL D- C- C-（ Ⅲ、 Ⅳ、 Ⅴ）
D D- D-（ Ⅳ、 Ⅴ）
AP
Ao
巻末資料３岩盤分類図
Pull-out Tests of Cable bolt (6 Places)
Obtaining Rock Joint (3 Places)
+550m EL
N
Rock Classification B Very Good CH Good CM Medium
Measurement of Joint Orientationin this Existing Tunnel
Rock Types Gneiss Migmatite
99
Investigation of Joint Orientation・ Major Joint Set : Strike E-W and Dip ±70 ～ 90°・ Another Joint Set : Strike NE-WS and Dip ±40 ～ 50°
Projection of Poles
Pole Density Contours
0
Equal angle projection, lower hemisphere
n=130 (P)Num total: 130
0
Equal angle projection, lower hemisphere
n=131 (P)Num total: 131
0
Equal angle projection, lower hemisphere
n=130max. dens.=5.82 (at 344/ 15)min. dens.=0.00Contours at:0.00, 1.00, 2.00, 3.00,4.00, 5.00,(Multiples of random distribution)
0
Equal angle projection, lower hemisphere
n=131max. dens.=9.44 (at 180/ 5)min. dens.=0.00Contours at:0.00, 1.00, 2.00, 3.00,4.00, 5.00, 6.00, 7.00,8.00, 9.00,(Multiples of random distribution)
Gneiss MigmatiteN
W
S
E
N
W
S
E
N
W
S
E
N
W
S
E
N
S
W E
Strike
Dip
Pole
Joint
×
1010
Situation of Obtaining In-Site Rock Joints
Recovered Core with Joint
Diamond Drilling
Joint
Joint
1111
・ Joint Deformability Parameters such as Normal and Shear Stiffness, Dilatancy Angle ・ Joint Shear Strength such as Cohesion and Internal Friction Angle
Normal Stress
Shear Displacement
Joint Mechanical Properties
Direct Shear Test of Rock Joints
Shear Test Equipment(Normal and Shear load are 1MN)
Rock Joint Specimen with extensometers
1212
0.00 0.05 0.10 0.15 0.20 0.25 0.300
2
4
6
8
10
12shear-3-1-v
(mm)垂直変位
(N
/mm
垂直
応力
2 )σn=10N/mm2
Normal Stiffness=67N/mm2/mm
Normal Displacement (mm)
No
rmal
Str
ess
(N/m
m2 )
- 0.2
- 0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.0 1.0 2.0 3.0 4.0 5.0
(mm)せん断変位
(mm
)垂
直変
位
3- 1(σ n=10MPa)2- 1(σ n=5MPa)1- 1(σ n=5MPa)2- 2(σ n=2MPa)
Di ｌ atancy angle=2.4°
Shear Displacement (mm)
No
rmal
Dis
pla
cem
ent
(mm
)
0
2
4
6
8
10
12
14
16
0 2 4 6 8 10 12
(N/ mm2)鉛直応力
(N/m
m2)
せん
断強
度
τ =0.5+σ n tan33°
τ =σ n tan54°
Normal Stress (N/mm2)
Sh
ear
Str
eng
th (
N/m
m2 )
Cohesion=0.57N/mm2
Internal Friction angle =33°
Results of Direct Shear Test
0
2
4
6
8
10
12
14
16
0.0 1.0 2.0 3.0 4.0 5.0
(mm)せん断変位
(N/m
m2)
せん
断応
力
3- 1(σ n=10MPa)2- 1(σ n=5MPa)1- 1(σ n=5MPa)2- 2(σ n=2MPa)
=60N/ mmせん断剛性 2/ mm
Shear Displacement (mm)
Sh
ear
Str
ess
(N/m
m2 ) Shear Stiffness=60N/mm2/mm
Shear Strength
1313
Pull-Out Test of Two Type Cable Bolts
Economical Support System should be used ・ Usual Support System for Large Cavern is Rock Anchor → Expensive ・ Proposed Support System is Rock Bolt and Cable Bolt → Economical ・ Special Cable Bolt with Dimples has very high Strength ・ Mechanical Properties of Cable bolt was estimated by Pull-Out Test
Usual Cable Bolt without Dimples（ PC-Cable Bolt ）
Special Cable Bolt with Dimples（ ST-Cable Bolt ）
1414
Situation of Pull-Out Tests
PC-Cable bolt
ST-Cable Bolt
Jock and Dial Gauge Pressure Pump
Diamond Drilling Inserting Cable Bolts
Pull-Out TestSetting up Equipments
1515
Results of Pull-Out TestsB片麻岩 級
0
50
100
150
200
250
0 2 4 6 8 10 12 14(mm)変位
(kN)
荷重
No.1- LNo.2- LNo.2- 上No.1- RNo.2- RNo.2- 下
ST
PC
Displacement (mm)
Load
(kN
)
Gneiss (B)
B伊西岩 級
0
50
100
150
200
0 2 4 6 8 10 12 14
(mm)変位
(kN
)荷
重
No.3- LNo.6- LNo.3- RNo.6- R
ST
PC
Displacement (mm)
Load
(kN
)
Migmatite (B)
0.00E+00
2.00E+04
4.00E+04
6.00E+04
8.00E+04
1.00E+05
1.20E+05
1.40E+05
0 50 100 150 200 250 300 350 400(kN/ m)付着強度
(kN/m
/m)
付着
剛性
B ST片麻岩 級（ ） CM ST片麻岩 級（ ）B ST)伊西岩 級（ CH ST)伊西岩 級（B PC片麻岩 級（ ） CM PC片麻岩 級（ ）B PC)伊西岩 級（ CH PC)伊西岩 級（
PC 53kN/ m：付着強度 以上 40100kN/ m/ m.付着剛性 以上
ST 270kN/ m：付着強度 以上 53900kN/ m/ m.付着剛性 以上
Strength (kN/m)
Stif
fnes
s (k
N/m
/m)
ST
PC
□Gneiss (B) ◇Migmatite(B) □Gneiss (B) ◇Migmatite(B)
△Gneiss (CH) ○Migmatite(CH)△Gneiss (CH) ○Migmatite(CH)
PC Strength above 53kN/m Stiffness above 40MN/m/m
ST Strength above 270kN/m Stiffness above 53MN/m/m
付着剛性付着強度
Stiffness (kN/m/m)Strength (kN/m)
Cable bolt model
1616
Mechanical Properties of Intact Rock Core Migmatite Gneiss
Compressive Strength (N/mm2) 191 176
Young’s Modulus (kN/mm2) 60.4 64.3
Poisson’s Ratio 0.24 0.26
Density (MN/m3) 0.027 0.027
Mechanical Properties Properties for Analysis
Rock Mass(Same as Intact Rock)
Young’s Modulus=64.3 kN/mm2 Poisson’s Ratio=0.25Density=0.27NM/m3
JointNormal Stiffness=67N/mm2/mm Shear Stiffness=60N/mm2/mm Dairatancy Angle=2.4°Cohesion=0.57N/mm2 Internal Frictional angle=33°
ST-Cable Bolt Shear Strength= 270kN/m Shear Stiffness=53MN/m/m
PC-Cable Bolt Shear Strength= 53kN/m Shear Stiffness=40MN/m/m
1717
Analysis Cases
SupportSupport In-Situ StressIn-Situ Stress
Case 1Case 1 Without SupportWithout SupportIsotropic Stress
σH=σv=14.4
（ N/mm2 ）(Overburden:500m)
Case 2Case 2Rock Bolt (Length=6m :Space=2m)Rock Bolt (Length=6m :Space=2m)
Double PC-Cable Bolt (Length=15m :Space=2m)Double PC-Cable Bolt (Length=15m :Space=2m)
Case 3Case 3Rock Bolt (Length=6m :Space=2m)Rock Bolt (Length=6m :Space=2m)
Double ST-Cable Bolt (Length=15m :Space=2m)Double ST-Cable Bolt (Length=15m :Space=2m)
Discontinuous Analysis by DEM
DEM Analysis is Performed to Establish the Behavior of Jointed Rock Mass and the Effect of Support System.
Cavern Direction is East and West
Huge TunnnelW48m×H54m
2070m2
Cavern Shape and Direction
”” AN
KO
AN
KO
””F
au
ltF
au
lt
”” 240
240 ゜゚--
ME
ME
””F
au
ltF
au
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fa
ult
Fa
ult
”” 240
240 ゜゚--
ME
ME
””F
au
ltF
au
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fa
ult
Fa
ult
”” 240
240 ゜゚--
ME
ME
””F
au
ltF
au
lt
””NAMARINAMARI”” FaultFaultNNN
Join
t S
trik
e
1818
200m
Strike E-W Dip ±70 ～ 90°(Major Joint Set)
Procedure of Analysis
Establishing Support System after Each Excavation Step
First Step SecondStep
Third Step
FourthStepAnalysis Model
200m
Strike NS-WS Dip ± 40 ～ 50°(Another Joint Set)
Joints are Generated Statistically According to the Joint Orientation
1919
Displacement Vector and Cable Axial Force
Case 3: RB+ST-Cable Bolt (Double)
Displacement of Right and Left Side Wall are nearly same because of Symmetrical Joint Dip Angle (±70 ～ 90°).
Displacement of Case-3 is smaller than Case-2 because of Support Effect of ST Cable Bolts
Case 1 ： Without Support
89 17
15
93
17
45
67 13
15
41
10
35
60 13
15
37
10
32
284
464415
（ kN ）
474
618620
（ kN ）
(mm)
(mm)
(mm)
Case 2 ： RB+PC-Cable Bolt (Double)
2020
Equivalent Continuum Analysis by Crack Tensor
ModelX
Z
Cavern shape and Region (528m×528m）
240m 240m48m
240
m23
4m54
mHuge TunnnelW48m×H54m
2070m2
Crack Tensor Analysis is Performed to Estimate the Relation between Tunnel Direction and Joint Orientation.
In-Situ Stress is Isotropic σH=σv=14.4 （ N/mm2 ）Case 1:Cavern Direction is East and West, parallel to Joint StrikeCase 2:Cavern Direction is North and South, right-angled to Joint Strike
”” AN
KO
AN
KO
””F
ault
Fau
lt
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fau
ltF
ault
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fau
ltF
ault
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultNNN
Case 1 Case 2
”” AN
KO
AN
KO
””F
ault
Fau
lt
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fau
ltF
ault
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fau
ltF
ault
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultNNN
Join
t S
trik
e
Join
t S
trik
e
2121
Displacement
Case 1 Case 2Output Set: I- DEAS Case 1Deformed(0.0391): Total Translation
9mm
15mm
39mm39mm
Output Set: I- DEAS Case 1Deformed(0.0391): Total Translation
9mm
15mm
39mm39mm
Output Set: I- DEAS Case 1Deformed(0.0181): Total Translation
12mm
18mm8mm
18mm
Output Set: I- DEAS Case 1Deformed(0.0181): Total Translation
12mm
18mm8mm
18mm
”” AN
KO
AN
KO
””F
ault
Fau
lt
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fau
ltF
ault
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fau
ltF
ault
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultNNN
Join
t S
trik
e ”” AN
KO
AN
KO
””F
ault
Fau
lt
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fau
ltF
ault
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultN”” A
NK
OA
NK
O””
Fau
ltF
ault
”” 240240 ゜゚--
ME
ME
””F
ault
Fau
lt
””NAMARINAMARI”” FaultFaultNNN
Join
t S
trik
e
Side Wall Displacement of Case 1 is 2 times Larger than Case 2 because of influence of Joint Strike Direction.
2222
Summary
Joint Orientation : At Proposed Site in Tochibora Mine, Major Joint Set Strike Direction is E-W and Dip Angle is ±70 ～ 90°Joint Properties : Normal and Shear Stiffness, Shear Strength are Estimated. Cable Bolt Properties : Shear Strength and Stiffness of ST and PC Cable Bolt are Estimated. Shear Strength of ST-Cable Bolt is 5 Times Higher than PC-Cable Bolt. ST-Cable Bolt is very Effective Support.Results of Analysis : Discontinuous and Equivalent Continuum Analysis are able to Estimate the Effect of Rock Support System and the Anisotropic Behavior of Jointed Rock Mass. Joint Orientation is very Important factor to decide the Cavern Direction.Further Investigation : It is Necessary for Estimation of Accurate Joint Orientation to investigate in Different Direction Tunnel or Bore Hole Additionally. Measurements of In-Situ Initial Stresses and In-Situ Tests on Rock Mass Deformability are indispensable.
2323
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