REPORT ON TRIAL RUN OF PLASMA ROCK SPLITTING METHOD
2007. 10.
·This report is made to suggest an idea of "how to proceed the rock fragmentation work effectively." Firstly, review the workability, safety and economy of the work in consideration of the site environment. And estimate, survey and analyze the effect of the vibration and sound to the nearby buildings during the job processing in order to prevent any foreseeable accidents.
2.1 Work scope Project name Location Owner Engineering Co.
·Daechi-Dong H Hotel & Sports Club New Construction Building Project. ·1004 Daechi-Dong, Gangnam-Ku, Seoul, Korea ·H & FP Co., Ltd.
·Taekyoung Maru General Construction Engineering Co. Ltd.
& Supervisor Constructor
·PETRO-PLASMA Co., Ltd.
2.2 Site Environment ·The location is 1004 Daechi-Dong, Gangnam-Ku, Seoul and around the site there are many large buildings such as Daeshin Building, Choi Building, Discussion & Medison Building, etc. Accordingly special attention should be given to the vibration, noise and flying rock during the work..
-2-
Gangnam Police
Gangnam Driving Licence Choi building.
Maedison county
Daeshin building.
Daechi-dong Hotel & Sports Club Construction Site
Parking Lot
[Fig 2. 1] Location of large Buildings
-3-
Maedison county
Choi building. Parking Lot
Trial Run Site
Daeshin building.
[Fig 2. 2] Detail Legend
site picture
[Pic. 2. 1] Actual working site
-4-
Daeshin Building
Parking Lot
Discuss & Medison Building
KORAD Building
[Picture. 2. 2] Buildings near project site
-5-
3.1 Scope of Plasma Rock Splitting Method This method is to generate plasma by transmitting electric energy in a few milli-seconds stored in the module of parallel-connected capacitors to the electrolyte (Electro Impact Cell) consisted of metal oxides (Al + CuO), and fragment rocks by utilizing the impact pulse wave and heat generated by the expansion of the plasma. This method is generally applied near to the densely populated residential area as there are no flying rocks.
3.2 Sequence of Plasma Rock Splitting Method 1. Charge energy to EPI
2. Discharge energy to Cell
3. Thermit Reaction
4. High heat and Impact pulse wave cause rock splitting
[Fig 3. 1] Plasma rock splitting method concept
3.3 Characteristics of Plasma Rock splitting Method Plasma method
Classification Principle
·Thermit reaction
Elements
·EPI + Electrolyte pack (Al) + (CuO)
Chemical formula
·2Al + 3CuO → Ala₂O₃ + 3Cu + 1,197KJ ·It is not governed by the regulation
-6-
[Chart 3. 1-1] Characteristics of Plasma Rock Splitting Method
Plasma Rock Splitting Method ·The electric energy stored in EPI is transmitted to the Electro Impact Cell composed of Aluminum and Copper oxide and generate plasma. ·The energy(about 7.9KV) stored in the capacitor are transmitted to the cell in milli-seconds which make the metal mixtures react to become the 4th state of matter, so-called plasma state and thermit reaction is processed to make high heat and high impact pulse power and break the rocks. ·In this plasma rock splitting method, the plasma state after rock splitting is immediately deoxidized (solidified) and so there are no flying rocks. Further the vibration time is less than 50ms and the vibration reducing index is quite Characteristics bigger than that of gun powder, which means the vibration reducing rate of this & method is far bigger than that o gun-powder method in distance.. The difference ·More than 80% of the vibration frequency of this method is over 80Hz, which is not coincide with the coherent frequency of the general constructions (15 ~ 20Hz), which is out of the resonance zone and do not affect the buildings.. ·Work efficiency of this method is about 5 times bigger than the non-vibration method and there are little second splitting. ·It can be applied regardless of the kinds of the rock. According the soft rock, mid rock and hard rock, the kinds of cells (600, 800, 1000mm) decided and it can be used in the underground water flowing area as the cell is made from water-proof vinyl film covered paper tube..
[chart 3. 1-2] characteristics of plasma Rock Splitting method
3.4 process of Plasma Rock Splitting Method Drilling (Hydraulic Crawler drill) Insert Impact Cell Connect cables Charging and Rock splitting secondary splitting and loading -7-
[Fig. 3. 1] Plasma method concept
Impact Cell
Insert the Cell
Stemming
Wiring
[Fig 3. 1] Plasma rock splitting preparation
4.1 Vibration Criteria
Classification
Seoul Metro
KNHC (Korea national Housing Cooperation)
MOCT (Ministry of Construction and Transportation)
kinds of buildings ·Historical heritage ·Building with defects such as crack ·Flawless building ·Concrete construction without pasted walls ·Historical heritage, Buildings mounted with precision machines
Allowable vibration limit cm/s (kine) 0.2 0.5 1.0 1.0~4.0 0.2
·General housing, Apartment
0.3
·Commerce or Office buildings, Public buildings
1.0
·RC, Plant with steel structure
4.0
·Human body fees the vibration but not complain of the inconvenience or pain
1.0
·Historical heritage, Cultural asset, Computer equipped building
0.2
·General housing, Apartment
0.3 ~ 0.5 1.0
·Commercial building ·Steel framed buildings or plants -8-
1.0~5.0
[chart 4. 1] National Allowable Vibration Limit
·This trial run was carried out in order to find the best actual method after evaluation of the environment by the Rock splitting works in the " Daechi-Dong H Hotel & Sports Club New building construction project" in the 1004 Daechi-Dong Gangnam-Ku,
5.1 Trial Run date and place. ·Trial Run Date : 2007. 10. 15. 13:23～14:30 ·Trial Run Place : The place where free space is formed well ·Measure point at site : 4 points ( 4ea - same distance linearly, 1ea - at the beam inside the site)
Maedison county
Choi building.
Parking Lot Measuring Point 6
Trial Run Site
Measuring Point 1~4 Measuring Point 5
Daeshin Building Measuring Point 7
[Fig 5. 1] trial run places and measuring points
-9-
Location #1
Location #2
Measurement NO.1
[Pic. 5. 1-1] Trial Run location and measuring point Measure NO.2
Measure NO 3
Measure NO 4
Measure NO 5
Measure NO6 - parking lot
Measure NO 7 Daeshin B.
[Pic 5. 1-2] Trial Run location and measuring point
5.2 Job site regulation for Vibration and Noise 5.2.1 Criteria for Vibration affection ∙The allowable limit of the vibration for the nearby buildings (Daeshin Building, Parking lot, etc) is to be 0.3cm/sec (kine).
Sector
Allowable limit
Ground vibration
0.3 cm/sec
Remarks ·Refer to the specification of the general houses and apartments of MOCT and KNHC
- 10 -
5.2.2 Criteria for Sounds ·The noise criteria for the nearby buildings (residential buildings) is 80dB(A) for the day time in week days / 75dB(A) for the day time in week end.
Level
Sound level
Remarks
80 dB(A)-weekdays (daytime) ∙“Regulation on noise and vibration” - Refer to the 75 dB(A)- weekend (daytime)
ordinance clause 29 para 2.3 'Life noise regulation'
5.3 Condition of the Trial run 5.3.1 Pattern of trial run
No.
Sequence hole(mm) cell depth(m)
resistance (m)
distance(m)holes(EA) cell vol.(kg)
total Vol(kg)
1
3rd
2.7
0.9
0.8
2
1.500
3.000
2
4th
2.7
0.9
0.8
2
1.500
3.000
3
6th
2.7
0.9
0.8
3
1.500
4.500
4
7th
2.7
0.9
0.8
3
1.500
4.500
5
1st
2.7
0.9
0.8
4
1.500
6.000
6
8th
2.7
0.9
0.8
4
1.500
6.000
7
10th
2.7
0.9
0.8
4
1.500
6.000
8
9th
2.7
0.9
0.8
5
1.500
7.500
9
11th
2.7
0.9
0.8
5
1.500
7.500
10
2nd
2.7
0.9
0.8
6
1.500
8.000
11
5th
2.7
0.9
0.8
6
1.500
8.000
12.
12th
2.7
0.9
0.8
8
1.500
12.000
13.
13th
2.7
0.9
0.8
8
1.500
12.000
Φ51
800
Total
60 [fig 5. 3] trial run pattern spec.
- 11 -
88
1st, 8th, 10th Splitting
Pattern (plane view)
Pattern (Section View)
[Fig 5. 2] 1st, 8th, 10th Pattern Diagram. 2nd, 5th Splitting Pattern (Plane view)
Pattern (Section view)
[Fig 5. 3] 2nd, 5th Pattern Diagram 3rd, 4th Splitting Pattern (Plane view)
Pattern (Section View)
- 12 -
[Fig 5. 4] 3rd, 4th Pattern Dia gram 6th, 7th Splitting Pattern (Plane view)
Pattern (Section View)
[Fig 5. 5] 6th, 7th pattern Diagram 9th, 11th Splitting Pattern (Plane view)
Pattern (Section View)
[Fig 5. 6] 9th, 11th pattern Diagram 12th, 13th Splitting Pattern (Plane view)
Pattern (Section View)
- 13 -
[Fig 5. 7] 12th, 13th Pattern diagram
5.3.2 Specification of Cell and EPI Cell for Trial Run
Size(mm)
800, 600mm
material
(AL)+(CuO)
Impact Cell 2Al + 3CuO → Ala₂O₃ + 3Cu +
reaction
1,197KJ
[chart 5. 4] Cell Spec. Specification of EPI
Size
EPI
cap.
Width(mm)
1,635
Hight(mm)
1,615
Depth(mm)
1,430
Weight(kg)
1,400
(V)
380
Energy(KJ)
268.92
Max.(V)
9,000
Max. Discharge Energy (MW)
134.46
[chart 5. 5] EPI Spec. for Trial run
- 14 -
5.3.3 Tire Matt against Flying Rock and Noise ·Safety matt was used in order to reduce noise and prevent flying rocks during the splitting work at site.
safety matt #1
safety matt #2
safety matt #3
5.3.5 Vibration Measuring device Device
picture
characteristics
quantity
·max. measuring limit : 254 mm/sec ·min. level to analysis : 0.0159 mm/sec ·TRIGGER LEVEL[vibration] : 0.13 ~ 253.9 mm/sec
Blastmate
7 ea
·Acceleration : 0.01 ~ 30 gal ·Vibration Discrepancy 0.0001“~1.5” ·Frequency analysis : USBM/DIN4150 Frequency
[chart 5. 7] Blastmate vibrograph
6.1 Result of Measurement ·The trial run result is as follows [Refer to the measurement report]
No.
BlastmateⅡ
BlastmateⅡ
BlastmateⅡ
BlastmateⅡ
(S/N:2475)
(S/N:2331)
(S/N:3051)
(S/N:2441)
NO 1 (site)
NO 2 (site)
NO 3 (site)
NO 4 (site)
Vibration cm/sec
Sound
Vibration
Sound
cm/sec 0.216
dB(A) 61.4
1
0.359
dB(A) 79.8
2
0.187
81.6
0.158
3
N/T
N/T
0.014
Vibration cm/sec
Sound
0.251
dB(A) 61.6
70.4
0.110
58.2
0.014
- 15 -
Vibration cm/sec
Sound
0.168
dB(A) 68.6
71.2
0.079
75.4
55.0
0.013
68.0
4
0.060
78.8
0.046
60.6
0.043
58.4
0.033
68.2
5
0.067
82.4
0.037
74.0
0.035
74.2
0.033
77.6
6
0.095
78.0
0.060
62.6
0.060
62.8
0.046
69.0
7
0.124
87.8
0.079
77.6
0.087
78.6
0.060
81.0
8
0.208
77.8
0.125
66.0
0.106
66.0
0.092
69.0
9
0.106
91.8
0.059
84.2
0.060
85.8
0.052
88.2
10
0.119
77.6
0.070
62.6
0.071
62.4
0.054
68.2
11
0.125
77.4
0.075
56.8
0.068
57.6
0.048
65.4
12
0.356
80.4
0.237
67.4
0.201
66.8
0.148
71.2
13
0.410
80.2
0.246
69.2
0.209
66.0
0.225
69.4
BlastmateⅡ No.
1 2 3 4 5 6 7 8 9 10 11 12 13
(S/N:2525) NO 5 (site beam) Vibration Sound cm/sec 0.183 0.079 0.024 0.056 0.103 0.054 0.067 0.117 0.056 0.068 0.068 0.129 0.256
dB(A) 65.4 78.6 59.8 66.0 80.4 66.8 82.6 75.4 88.0 69.4 60.0 69.6 70.0
BlastmateⅡ (S/N:1898) NO 6 (parking lot) Vibration Sound cm/sec 0.121 0.160 0.060 0.140 0.094 0.156 0.117 0.123 0.181 0.108 0.159 0.105 0.135
dB(A) 60.4 65.8 60.8 66.0 69.4 63.4 65.2 63.6 69.8 67.4 64.2 68.4 66.2
BlastmateⅡ (S/N:2601) NO 7 (Daeshin Building) Vibration Sound cm/sec N/T N/T N/T N/T N/T N/T N/T N/T N/T N/T N/T N/T N/T
dB(A) N/T N/T N/T N/T N/T N/T N/T N/T N/T N/T N/T N/T N/T
remarks ※ N/T(No Triggered) : ·When ground vibration from splitting is completely disappeared at the point of sensor or the effect was so little, under the point of Trigger Level (0.013cm/sec), the measuring device could not record the result.. ·Just in time of the splitting, nearby vibration affected the measuring device and it could not record the pure vibration.
- 16 -
6.2 Effect analysis of the Trial run. ·According to the pattern a13 tests are carried out. The movement or size of the fragmentation was satisfactory..
Before splitting
After splitting #1
After splitting #2
6.3 Analysis of the measurement 6.3.1 Analysis on ground vibration ·Ground vibration was measured at 4 linear points inside site including one at beam, and a Daeshin Building, at Parking lot and Safety matter. ·The vibration data at the beam (measurement NO4) show 0.024∼0.256cm/sec and the the maximum recorded 0.256cm/sec. The Data of NO1 distributes 0.060∼0.410cm/sec and the maximum was 0.410cm/sec. ·When comparing the data at beam and No. 1, the data at beam shows lower than that of no.1. it is surmised that the vibration at beam was reduced due to the space in the hole around the beam.. ·The measurement result of 4 points in the site: Average 0.170cm/sec at 20m, Average 0.109cm/sec at 25m, Average 0.101cm/sec at 30m, Average 0.081cm/sec at 35m. Vibration reduction rate from 20m to 25m and the rate was small after 25m. ·The data at Parking lot was 0.060∼0.181cm/sec and the maximum was 0.181cm/sec, which is 60% level of the allowable limit, 0.3cm/sec. ·The data at the safety matter in the site, Daeshin Building, any vibration was detected as it is under the Trigger Level 0.013cm/sec..
Measure Point
Measured Vibration
Avr. vibration
MP NO1 (20m)
0.060～0.410
0.170
MP NO2 (25m)
0.014～0.246
0.109
MP NO3 (30m)
0.014～0.251
0.101
MP NO4 (35m)
0.013～0.225
0.081
(Avr. Distance)
- 17 -
[chart 6. 2] Measuring result at site Measure Point
Limit
Parking lot Daeshin building
0.5 cm/sec
Measured Vibration
Pass or not
0.060～0.181 cm/sec
OK
N/T (under 0.013cm/sec)
OK
[chart 6. 3] Measuring result at the safety matter
vibration at Beam at site
[Fig 6. 1] vibration data at beam
Avr. vibration speed at site
/
Parking Lot
Avr. vibration speed at site
Daeshin building
[Fig 6. 2] Vibration Data at safety matter near the site.
6.3.2 Analysis on Sound - 18 -
·The sou und data att the safety y matter, Parking lot was 60.4∼ ∼69.8dB (A)) and the maximum m is 69.8dB(A A), which is 87% of the allowable limit of the site s 80dB(A)). ·The soun nd data at th he safety matter m Daesh hin Building was not rec corded. [The sou und Sensor is related to t the Geop phone. So if i vibration is not mea asured the sound s is no ot measure ed either - As A the groun nd vibration n speed (Ab bout 1000~3 3000m/sec) is faster tha an the sound d transmittting speed in i the air (A About 340m//sec), set th he Trigger Source S as Ge eophone.]
Meassuring Poin nt
Alllowable liimit
Pa arking lot Daesh hin Buildin ng
80 dB(A)
Measured d noise
Passed d or not
60.4～69.8 8dB(A)
OK
N/T T
OK
[chart 6. 4] 4 Sound level l mea asured at safety s ma atter
Pa arking lott
Daeshin B Building
[Fif 6. 3]] Sound le evel distriibution grraph at saffety matte er near sitte.
6.4 Regression n Analys sis & Ana alogize Vibration V n Equatiion 6.4.1 Ba ackground of revie ew ·In orderr to apply th he data from m the trial run r to [equa ation 6. 1], regression r analysis is required on n the test result. r ㆍ ㆍㆍㆍㆍㆍㆍ ㆍㆍㆍㆍㆍㆍㆍㆍㆍ[equ uation 6. 1] V : Speed d of ground d vibration (cm/sec, ( mm m/sec, in/se ec), D : Distance from viibration orig gin (m) , W : Cell weig ght(Kg), K : coefficient c a according to the nature e a conditio on of splittin ng pattern. of rock and - 19 -
·For thesse if we take e log for bo oth sides of [equation 6. 6 1] ,it beco ome [equation 8. 2], which w follows simple liinear regresssion model as [equatio on 6. 3].
ㆍㆍㆍㆍㆍㆍㆍㆍㆍㆍㆍㆍㆍㆍ[식 6. 2] ㆍㆍㆍㆍㆍㆍㆍ ㆍ[식 6. 3] ·In the abo ove simple model, is showing s un nknown line ear relation, and called d populatio on regressiion line. Th he analogiziing method d to make th he sum of the square of errors () ( generate ed when ma aking popullation regre ession line, is called method m of le east squaress. This is the e most com mmonly use ed method to o analogize e Vibration equation. e ·The α and a β from the least square meth hod is calle ed 'east squ uare estima ator', it is ca alculated as follows. , ㆍㆍㆍㆍㆍㆍㆍ[eq quation 6. 4] v eq quation callculated as above, 50% of the data d is loca ated upper part of the e ·In the vibration equation n and the rest r is located at the lower part of t 도 equation. Tha at is it is th he vibration n equation n with 59 relliability. Bu ut in order to increase safety and reliability, r v vibration eq quation with h 95% reliabilityis req quired. For this, in the same e state of the e slope (β) of o the regre ession line, move m the (α α) and get a new (α) as follow ws. ndard error (SE(α)) is calculated c ass [equation 6. 5]. ·The stan
ㆍㆍㆍㆍㆍㆍㆍ[equa ation 6. 5] The σ in this equatio on is Standard deviation n and calculated as [eq quation 6. 7]].
ㆍㆍㆍ[equation n 6. 6]
on t, the valu ue of 95% reliability r is [equation 6. 6 7]. ·α follows distributio ㆍㆍㆍㆍㆍㆍㆍㆍㆍㆍ ㆍㆍㆍㆍㆍ[e equation 6. 7]
- 20 -
·In the abo ove equation n, shows the e value, deg gree of free edom n-2 in n the t Distribution charrt and in ca ase thearea a is (100-a)% %. As the va alue of the reliability r iss 95%, a is tthe value off 5%, t value e for this value v is show wn in [chartt 6. 5].
Degree e of freedom
Degrree of freed dom
De egree of fre eedom
D Degree off freedom
(n-2) 1 2 3 4 5 6 7 8 9 10
(n--2) 11 12 13 14 15 16 17 18 19 20
(n-2) 21 22 23 24 25 26 27 28 29 30
(n-2) 40 60 120 ∞
6.31 14 2.92 20 2.35 53 2.13 32 2.01 15 1.94 43 1.89 95 1.86 60 1.83 33 1.81 12
1..796 1..782 1..771 1..761 1..753 1..746 1..740 1..734 1..729 1..725
1.721 1.717 1.714 1.711 1.708 1.706 1.703 1.701 1.699 1.697
[ [Chart 6. 5] T Distrribution ch hart
6.4.2 Vibration V n regress sion Ana alysis Squa are Root Vibration estimated equation e An nalysis Result
An nalysis gra aph
50% % reliabiility 95% % reliabiility SD(SE E)
0.128
Coeffic cient 0.75 2
(R ) ·Standard deviattion (SE) = 0.12 28 < 0.5 and d near to 0
revie ew
·Coe efficient (R2)=0.75 > 0.7 and near tii 1 - 21 -
1.684 1.671 1.658 1.645
[chartt 6. 6] vibrration ana alysis - sq quare roott Cubic Root viibration estimated equation A Analysis Re esult
An nalysis gra aph
50% % reliabiility 95% % reliabiility Standa ard dev.(S SE)
0.122
Coeffic cient 0.77 2
(R ) Revie ew
·Stand dard deviation (SE)) =0.1 122 < 0.5 an nd near to 0 ·coeffiicient(R2)=0 0.77 > 0.7 , near to 1
[charrt 6. 7] vib bration an nalysis - cu ubic root
remark ks ·In regre ession analy ysis apply 95% 9 Fitting, coefficient(R2) should d be biggerr than 0.7, recommend r d standard d deviation((SE) under 0.2,. 0 If Stand dard deviattion (SE) is over 0.5, it can not be applied. ☞ “BLASTIN NG GUIDAN NCE MANUA AL ; By Mich hael F. Rose enthal and Gregory G L. M Morlock)"
6.4.3 Estimatio E on of vib bration speed s by y diatanc ce (squarre root) Vib bration Distribution
rremarks ·Estim mate vibratiion speed by b applying g 95% reliability r sq quare root equation e ·Estim mate vibratiion speed by b changing g the ce ell amount b by pattern 량 -Charrge : 1.000 k kg/delay -Charrge : 1.500 k kg/delay -Charrge : 2.000 k kg/delay -Charrge : 2.500 k kg/delay -Charrge : 3.000 k kg/delay
[c chart 6. 8] Vibration n distribu ution Grap ph by dista ance Grap ph-Square e root
- 22 -
Distance (m)
Particle Velocity (cm/sec) 1.000 (kg/d)
1.500 (kg/d)
2.000 (kg/d)
2.500 (kg/d)
3.000 (kg/d)
10
0.188
0.246
0.296
0.343
0.386
20
0.076
0.099
0.120
0.138
0.156
30
0.045
0.058
0.070
0.081
0.092
40
0.031
0.040
0.048
0.056
0.063
50
0.023
0.030
0.036
0.042
0.047
60
0.018
0.024
0.028
0.033
0.037
70
0.015
0.019
0.023
0.027
0.030
80
0.012
0.016
0.019
0.023
0.025
90
0.011
0.014
0.017
0.019
0.022
100
0.009
0.012
0.015
0.017
0.019
110
0.008
0.011
0.013
0.015
0.017
120
0.007
0.009
0.011
0.013
0.015
130
0.007
0.009
0.010
0.012
0.013
140
0.006
0.008
0.009
0.011
0.012
150
0.005
0.007
0.009
0.010
0.011
160
0.005
0.007
0.008
0.009
0.010
170
0.005
0.006
0.007
0.008
0.009
180
0.004
0.006
0.007
0.008
0.009
190
0.004
0.005
0.006
0.007
0.008
200
0.004
0.005
0.006
0.007
0.008
210
0.003
0.005
0.006
0.006
0.007
[chart 6. 9] Vibration speed Distribution by distance - square root
6.4.4 Estimate Vibration speed by distance (cubic root) Vibration Distribution
Remarks ·Estimate vibration speed by using 95% reliability, cubic root ·Estimate vibration speed by changing cell amount by pattern and distance -Charge : 1.000 kg/delay -Charge : 1.500 kg/delay -Charge : 2.000 kg/delay -Charge : 2.500 kg/delay -Charge : 3.000 kg/delay
[chart 6. 10] vibration speed distribution graph by distance Graph - cubic root - 23 -
Distance (m)
Particle Velocity (cm/sec) 1.000 (kg/d)
1.500 (kg/d)
2.000 (kg/d)
2.500 (kg/d)
3.000 (kg/d)
10
0.325
0.394
0.452
0.503
0.548
20
0.120
0.146
0.168
0.186
0.203
30
0.067
0.082
0.094
0.104
0.114
40
0.045
0.054
0.062
0.069
0.075
50
0.032
0.039
0.045
0.050
0.055
60
0.025
0.030
0.035
0.039
0.042
70
0.020
0.024
0.028
0.031
0.034
80
0.017
0.020
0.023
0.026
0.028
90
0.014
0.017
0.019
0.022
0.024
100
0.012
0.015
0.017
0.019
0.020
110
0.010
0.013
0.015
0.016
0.018
120
0.009
0.011
0.013
0.014
0.016
130
0.008
0.010
0.012
0.013
0.014
140
0.007
0.009
0.010
0.012
0.013
150 160
0.007 0.006
0.008 0.007
0.009 0.009
0.010 0.010
0.011 0.010
170
0.006
0.007
0.008
0.009
0.010
180
0.005
0.006
0.007
0.008
0.009
190
0.005
0.006
0.007
0.007
0.008
200
0.004
0.005
0.006
0.007
0.008
210
0.004
0.005
0.006
0.006
0.007
[chart 6. 11] vibration speed distribution - Cubic root
6.4.5 Estimate Cell amount by distance(Allowable limit 0.3cm/sec) Cell amount by distance
remarks ∙Use 95% reliability vibration equation to estimate cell amount by distance when the vibration allowable limit is 0.3cm/sec
·The cross point of square root and cubic Root is 25m away from the splitting point
[chart 6. 12] Cell amount graph by distance Graph - 0.3cm/sec - 24 -
Distance (m)
Particle Velocity - 0.3cm/sec base SQUARE ROOT
CUBIC ROOT
적용값
2
0.081
0.007
0.007
4
0.326
0.054
0.054
6
0.733
0.183
0.183
8
1.304
0.434
0.434
10
2.037
0.847
0.847
12
2.934
1.463
1.463
13
3.443
1.861
1.861
14
3.993
2.324
2.324
16
5.216
3.469
3.469
18
6.601
4.939
4.939
20
8.149
6.775
6.775
22
9.861
9.017
9.017
24
11.735
11.707
11.707
25
12.733
13.232
12.733
26
13.772
14.884
13.772
28
15.972
18.590
15.972
30
18.336
22.865
18.336
32
20.862
27.749
20.862
34
23.551
33.284
23.551
36
26.403
39.510
26.403
38
29.419
46.468
29.419
[chart 6. 13] Cell amount distribution by distance - 0.3cm/sec base.
6.5 Review on the Method in the site 6.5.1 Scope of the review ·Reviewed test result based on the vibration allowable limit 0.3cm/sec for the safety matter and test result by the cell amount by distance.
6.5.2 Review result ·Based on the regulation for the safety matter, the allowable limit of o.3mm/sec, trial run was carried out in order to apply plasma rock splitting method adequately. From the test result, Non-vibration method ( hydraulic Jack, breaker fragmentation etc) was recommended within 13m from the safety matter and plasma method is recommended over 13m from the safety matter. - 25 -
method
Non-vibration method
Plasma method
cell volume (kg/d)
-
1.500
distance(m)
within 13m
Over 13m
[chart 6. 14] rock splitting method calculation by distance at site
Maedison county
Choi building.
Parking Lot
Daeshin Building
Rock Fragmentation – Hydraulic, Breaker etc Rock Fragmentation – Plasma Rock Splitting
[Fig 6. 4] review rock splitting method based on test result
6.5.3 Review wall part of the site ·Measured vibration at the wall of the site during breaker works and the maximum figure was Max. 1.8 cm/sec. By applying estimated vibration equation from the trial run, 2.2m distance is calculated. ·Accordingly when applying plasma method near the wall, the distance should be over 2,2m to control the vibration speed under the level of breaker vibration.
- 26 -
Vibration speeed by breaker (cm/sec)
1st
2nd
3rd
0.970
1.840
1.720
[chart 6. 15] Breaker vibration speed
Distance (m)
Particle Velocity (cm/sec) 1.000 (kg/d) 1.500 (kg/d) 2.000 (kg/d) 2.500 (kg/d) 3.000 (kg/d)
2.0
1.549
2.019
2.438
2.821
3.179
2.1
1.453
1.894
2.287
2.647
2.982
2.2
1.367
1.782
2.152
2.490
2.806
2.3
1.290
1.682
2.030
2.349
2.647
2.4
1.220
1.591
1.920
2.222
2.504
2.5
1.156
1.508
1.820
2.106
2.374
2.6
1.098
1.432
1.729
2.001
2.255
2.7
1.045
1.363
1.646
1.905
2.146
2.8
0.997
1.300
1.569
1.816
2.046
2.9
0.952
1.241
1.499
1.734
1.954
3.0
0.911
1.188
1.434
1.659
1.869
Breaker works
Vibration measure
[Pic 6. 1] Vibration check during wall part breaker works
- 27 -
·From the trial run at “Daechi-Dong H Hotel & Sports club new building construction project" following conclusion is induced.
7.1 Blasting Control Criteria application
remarks ·Refer to the specification of the general houses and
Ground Vibration
Noise level
0.3 cm/sec
apartments
80 dB(A)- week day ·“Regulation on noise and vibration” - Refer to the daytime 75 dB(A)-week end ordinance clause 29 para 2.3 'Life noise regulation' daytime [chart 7. 1] vibration limit at site
7.2 Vibration, Sound level measurement result 7.2.1 Vibration ·The vibration data at the beam (measurement NO4) show 0.024∼0.256cm/sec and the the maximum recorded 0.256cm/sec. The Data of NO1 distributes 0.060∼0.410cm/sec and the maximum was 0.410cm/sec. ·When comparing the data at beam and No. 1, the data at beam shows lower than that of no.1. it is surmised that the vibration at beam was reduced due to the space in the hole around the beam. ·The measurement result of 4 points in the site : Average 0.170cm/sec at 20m, Average 0.109cm/sec at 25m, Average 0.101cm/sec at 30m, Average 0.081cm/sec at 35m. Vibration reduction rate from 20m to 25m and the rate was small after 25m. ·The data at Parking lot was 0.060∼0.181cm/sec and the maximum was 0.181cm/sec, which is 60% level of the allowable limit, 0.3cm/sec. ·The data at the safety matter in the site, Daeshin Building, any vibration was traced as it is under the Trigger Level 0.013cm/sec..
measue point (Avr. distance)
measured vibration
average vibration
NO1 (20m)
0.060～0.410 0.014～0.246 0.014～0.251
0.170 0.109 0.101
NO2 (25m) NO3 (30m)
- 28 -
0.013～0..225
NO4 (35m m)
mea asure poin nt
alllowable liimit
Pa arking lot Daeshin Buildin ng
0.3 cm/sec c
0.081
measured m v vibration
passed or failed
0.0 060～0.181 1 cm/sec
OK
N/T (un nder 0.013cm//sec)
OK
[charrt 7. 2] vib bration che eck inside the site 7.2.2 NO OISE ·The sou und data at the safety y matter, Parking P lot was 60.4∼ ∼69.8dB(A) and the maximum m is 69.8dB(A A), which is 87% of the allowable limit of the site s 80dB(A)). ·The soun nd data at th he safety matter m Daesh hin Building wast not re ecorded. [The sou und Sensor are related d to the Geo ophone. So if vibration n is not mea asured the sound s is no ot measure ed either - As A the groun nd vibration n speed (Ab bout 1000~3 3000m/sec) is faster tha an the sound d transmittting speed in i the air (A About 340m//sec), set th he Trigger Source S as Ge eophone.]
measre pointt
alllowable liimit
measured m sound
passed or Failed
60.4～69.8 8dB(A)
OK
N/T T
OK
Pa arking lot Daeshin buildin ng
80 dB(A)
[chart 7. 4] 4 sound level l chec ck in the safety s ma atter
7.3 Pre evention n of Flyin ng Rock ·In case of o flying roc ck a big acc cident can happen. h Acc cordingly safety s matt w was covered d to preven nt the flying rock in th he trial run n for safety purpose. safety. s Safetty matt is sstrongly rec commended d he actual sp plitting work ks to reduce e noise as well w as to pre event flying g rocks. during th
7.4 Analogize vibration equatiion 9
(Squarre Root)
(C Cubic Roott)
95% reliability y (Sq quare Roo ot)
(Cubic Root)
- 29 -
[chart 7. 5] regression analysi
7.5 Review Rock splitting method ·Non-vibration method ( hydraulic Jack, breaker fragmentation etc) was recommended within 13m from the safety matter and plasma method is recommended over 13m from the safety matter.
method
Non-vibration method
Plasma method
cell volume (kg/d)
-
1.500
distance(m)
within 13m 이내
Over 13m
[chart 7. 6] rock splitting method calculation by distance at site ·Measured vibration at the wall of the site during breaker works and the maximum figure was Max. 1.8 cm/sec. By applying estimated vibration equation from the trial run, 2.2m distance is calculated. ·Accordingly when applying plasma method near the wall, the distance should be over 2,2m to control the vibration speed under the level of breaker vibration.
estimate vibration speed by distance
cell amount 1.500kg 2.0m 2.1m 2.2m 2.3m 2.4m 2.5m 2.6m 2.7m 2.8m 2.9m 3.0m 2.019 1.894 1.782 1.682 1.591 1.508 1.432 1.363 1.300 1.241 1.188
cm/sec
- 30 -
Maedison county
Choi building.
Parking Lot
Daeshin Building
Rock Fragmentation – Hydraulic, Breaker etc Rock Fragmentation – Plasma Rock Splitting
7.6 Conclusion and recommendation The Trial Run showed satisfactory result in consideration of safety, vibration and noise. Recommend to provide safety measure (whistling before splitting, covering safety matt, etc. ) in consideration of safety matter before actual work.. Plasma rock splitting works are recommended to a distance over 13m from the safety matter and in every splitting work, recommend to review previous work result and readjust the quantity of holes, cellls, cell sizes, distances, resistance space etc.
- 31 -
This
Report
that
is
written
in
translated by PETRO-PLASMA. Phone : 82-2-952-3199
FAX : 82-2-952-3196
- 32 -
Korean
w
