JP2881179B2 - A method for determining the safest maximum charge in perforation blasting. - Google Patents
A method for determining the safest maximum charge in perforation blasting.Info
- Publication number
- JP2881179B2 JP2881179B2 JP29707788A JP29707788A JP2881179B2 JP 2881179 B2 JP2881179 B2 JP 2881179B2 JP 29707788 A JP29707788 A JP 29707788A JP 29707788 A JP29707788 A JP 29707788A JP 2881179 B2 JP2881179 B2 JP 2881179B2
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- Japan
- Prior art keywords
- charge
- length
- blasting
- amount
- charge amount
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D1/00—Blasting methods or apparatus, e.g. loading or tamping
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
Description
【発明の詳細な説明】 a)産業上の利用分野 この発明は、岩盤の硬度未知な現場において実際に穿
孔発破作業を開始する際に、試験発破を行なって、その
岩盤を破壊するのに有効な安全最多装薬量を迅速確実に
決定する方法に関する。DETAILED DESCRIPTION OF THE INVENTION a) Industrial application field The present invention is effective for performing test blasting and actually breaking rock at the site where the hardness of rock is unknown at the site where the hardness is unknown. The present invention relates to a method for quickly and reliably determining a safe and safe maximum charge amount.
b)従来の技術 従来、発破の装薬量を決定する算出式としてハウザー
の公式、すなわち、 装薬量L(kg)=発破常数C×最少抵抗線W3 が周知である。この公式は、円錐の体積を求める公式V
=1/3×π×r2×hの一変形であって、前記r2とhとを
いずれもWに置き換えてみれば、前記ハウザーの公式が
実現する。b) Description of the Related Art Conventionally, Hauser official as a calculation expression that determines the charge amount of blasting, i.e., it is well known Sokusuriryou L (kg) = blast constant C × minimal resistance wire W 3. This formula is a formula for the volume of a cone, V
= 1/3 x π x r 2 x h. If both r 2 and h are replaced by W, the Hauser formula is realized.
c)発明が解決しようとする課題 このハウザーの公式は、火薬の体積を0と仮定し、装
薬位置も極小の一点として考える限りにおいては正確で
ある。c) Problems to be Solved by the Invention This Hauser's formula is accurate as long as the volume of the explosive is assumed to be 0 and the charging position is considered as a minimum point.
しかしながら実際の発破工事においては、装薬には所
定の長さと径とが存在し、とりわけ、近年、機械の大型
化に伴い、発破穿孔長が例えば22mにも達する場合があ
り、その長い穿孔長に対して装薬は長い棒状の状態で行
われる。このように、ハウザーの公式は実際行われてい
る棒状装薬法に適しない。However, in actual blasting work, the charge has a predetermined length and diameter, and in particular, in recent years, with the enlargement of machines, the blasting perforation length may reach, for example, 22 m, and the long perforation length In contrast, charging is performed in a long rod-like state. Thus, Hauser's formula is not suitable for the practice of rod-shaped charging.
穿孔発破作業で、もっとも注意すべき点は、爆破に伴
なって生ずる飛石の及ぼす危険性の問題であり、装薬量
が過多の場合には作業員を含めた周囲一帯が飛石の危険
にさらされる。しかしながら、飛石の危険ばかりが過大
に考慮されて装薬量が過少であると作業能率がはかどら
ず、安全ではあっても工事の完成が遅れることになる。
そこで、作業の安全と能率の双方を両立させるために、
爆破に伴なって飛石が生じても、その飛石による実際の
被害が発生しない限界点となる安全最多装薬量を当該作
業現場において早急に探り出す手法が要求される。The most important thing to note about drilling blasting is the risk of stepping stones caused by blasting.If the amount of charge is excessive, the surrounding area, including workers, is at risk of stepping stones. It is. However, if only the danger of stepping stones is considered excessively and the amount of charge is too small, the working efficiency will not be improved, and even if it is safe, the completion of the construction will be delayed.
Therefore, in order to balance both work safety and efficiency,
Even if a stepping stone is generated by the blasting, a method is required to quickly find a safe maximum charge amount at the work site, which is a limit point where actual damage by the stepping stone does not occur.
この発明の目的は、岩盤の硬度未知な現場において実
際に穿孔発破作業を開始する際に、作業の安全と能率の
双方を両立させるために、試験発破を行ない、爆破に伴
なって生ずる飛石による実害が発生しない限界点となる
最多装薬量を迅速確実かつ簡単容易に決定する方法を提
供することである。An object of the present invention is to perform a test blast to achieve both work safety and efficiency when actually starting a drilling and blasting operation at a site where the hardness of the rock is unknown, and to use a stepping stone generated by the blasting. It is an object of the present invention to provide a method for quickly, surely, easily and easily determining the maximum amount of charge, which is a critical point at which no actual harm occurs.
d)課題を解決するための手段 この発明は、上記の目的を達成するために、 所望の穿孔長Hと穿孔径rとによって形成される孔に
装薬比重Aを有する所望の装薬量を入れて試験発破を行
なう場合に、 まず、その爆破の影響が地表にあらわれる規模の装薬
量を最少装薬量L、そのときの装薬長を最少装薬長lと
して L=(π/4)r2・l・A そのときの込物長を初期込物長Dとして D=H−l を確認し、 次に、その初期込物長Dの3/4の長さを補助装薬長l
a、すなわち、 la=(3/4)D とし、 その補助装薬長laに対応する補助装薬量Laを前記最少
装薬量Lに加えた合計装薬量L+La、すなわち、 L+La=(π/4)r2(l+la)A を安全最多装薬量とし、 その安全最多装薬量L+Laで穿孔発破を行なう点にあ
る。d) Means for Solving the Problems In order to achieve the above-mentioned object, the present invention provides a method for forming a hole having a desired specific gravity A in a hole formed by a desired hole length H and a hole diameter r. When the test blasting is performed, first, the charging amount at a scale where the effect of the blast appears on the ground surface is set to the minimum charging amount L, and the charging length at that time is set to the minimum charging length l, and L = (π / 4 ) R 2 · l · A Confirm D = H−1 as the initial length D of the loaded object at that time, and then determine the length of 3/4 of the initial length D as the auxiliary charge length. l
a, that is, la = (3/4) D, and the total charge amount L + La obtained by adding the auxiliary charge amount La corresponding to the auxiliary charge length la to the minimum charge amount L, that is, L + La = (π / 4) r 2 (l + la) A is defined as the safest maximum charge amount, and piercing blasting is performed at the safest maximum charge amount L + La.
更に、この発明は、上記の目的を達成するために、初
期込物長Dの1/2の長さを補助装薬長l′、すなわち、 l′=(1/2)D とし、 その補助装薬長l′に対応する補助装薬量La′を前記
最少装薬量Lに加えた合計装薬量L+La′、すなわち、 L+La′=(π/4)r2(l+l′)A を標準装薬量とし、 その標準装薬量L+La′で穿孔発破を行なう点にあ
る。Further, in order to achieve the above object, the present invention sets the length of the initial filling length D to 1/2 of the auxiliary charge length l ', that is, l' = (1/2) D, The total charge amount L + La 'obtained by adding the auxiliary charge amount La' corresponding to the charge length l 'to the minimum charge amount L, that is, L + La' = (π / 4) r 2 (l + l ') A is standardized. The point is that the drilling blast is performed with the standard charge L + La 'as the charge.
e)作用 試験発破を行なって、その爆破の影響が地表にあらわ
れる最少装薬量Lにおける初期込物長Dを、まず、最初
に確認する。e) Action A test blast is performed to first confirm the initial inclusion length D at the minimum charge L at which the effects of the blast appear on the ground.
しかしながら、この最少装薬量Lのみでは地表に亀裂
が生じる程度であって地表付近の岩盤の破壊が微弱過
ぎ、後処理に時間と手間がかかって作業の能率が上らな
い。従って地表付近の岩盤に対してはまだ破壊を加える
余地が残っているものと判断される。However, only the minimum charge amount L causes cracks on the ground surface, and the rock near the ground surface is too weakly destructed, so that post-processing takes time and labor, and the work efficiency is not improved. Therefore, it is judged that there is still room for destruction of the rock near the ground surface.
そこで、前記最少装薬量Lにおける初期込物長Dの3/
4の長さに相当する補助装薬量Laを最少装薬量Lに加え
て、前記破壊の未熟な地表付近に対して爆破が生じるよ
うにすれば、飛石による実害の発生に至らない程度で過
不足のない破壊が得られ、安全と能率の双方が充足され
る。Therefore, the initial charge length D at the minimum charge amount L is 3 /
If the auxiliary charge amount La corresponding to the length of 4 is added to the minimum charge amount L so that blasting occurs near the undeveloped ground surface, the actual damage due to the stepping stone does not occur. Destruction without excess or shortage is obtained, and both safety and efficiency are satisfied.
他方において、前記初期込物長Dの1/2の長さに相当
する補助装薬量La′を最少装薬量Lに加えれば、その岩
盤の破壊に最も安全な標準装薬量L+La′が得られる。On the other hand, if the auxiliary charging amount La ′ corresponding to half of the initial filling length D is added to the minimum charging amount L, the standard charging amount L + La ′ which is safest to break the rock is obtained. can get.
f)実施例 第1図において、穿孔径r(mm)、 穿孔長H(m)=装薬長l(m)+初期込物長D(m) 破壊岩盤量V(m3)は、円錐の体積を求める公式から、 破壊岩盤量V(m3) =1/3×π×破壊半径R2(m2)×穿孔長H(m) =穿孔長H(m)×破壊半径R2(m2) 最少装薬量L(kg)は、円柱の体積を求める公式から、 最少装薬量L =円柱の断面積(π/4)r2×装薬長l×装薬比重A このような諸元を有する試験穿孔発破の構成におい
て、穿孔長H(m)中におけるx(m)点は最少装薬長
l(m)と初期込物長D(m)との境界を示し、そのx
点まで装薬をして発破させると、地表G.Lが僅かに浮き
上がる程度の爆破力となり、それに要する火薬が最少装
薬量L(kg)となる。そこで、そのときの初期込物長D
(m)を確認する。例えばH=14m、r=140mmの孔にお
いて、最少装薬長l=7mの装薬をして試験発破した場合
に、地表G.Lに影響が生じたとすれば、そのときの初期
込物長D=7mとなる。f) Example In FIG. 1, the perforation diameter r (mm), the perforation length H (m) = the charging length l (m) + the initial inclusion length D (m) The fractured rock mass V (m 3 ) is a cone From the formula for calculating the volume of, the amount of fractured rock mass V (m 3 ) = 1/3 × π × fracture radius R 2 (m 2 ) × perforation length H (m) = perforation length H (m) × fracture radius R 2 ( m 2 ) The minimum charge amount L (kg) is obtained from the formula for calculating the volume of a cylinder, the minimum charge amount L = the cross-sectional area of the cylinder (π / 4) r 2 × the charge length 1 × the specific gravity A of the charge In the test drilling blast configuration having various specifications, the point x (m) in the drilling length H (m) indicates the boundary between the minimum charge length l (m) and the initial load length D (m). x
When a point is charged and blasted, the blasting force is such that the ground surface GL slightly rises, and the explosive required for the blasting becomes the minimum charged amount L (kg). Therefore, the initial inclusion length D at that time
Check (m). For example, in the case of a hole of H = 14 m and r = 140 mm, when the test blasting is performed by charging with the minimum charging length l = 7 m, if the ground surface GL is affected, the initial load length D = 7m.
しかしながら、前記条件における最少装薬量L(kg)
で爆破した場合に、岩盤の破壊状況を検討してみると、
第1図で示すように、地表G.L付近では僅かに亀裂が生
じた程度であって、この程度の破壊では後処理作業に手
数と時間がかかって非能率的である。However, the minimum charge L (kg) under the above conditions
In the case of bombing, when examining the situation of rock destruction,
As shown in FIG. 1, a slight crack is generated in the vicinity of the ground surface GL, and such a degree of destruction requires time and labor for post-processing work, which is inefficient.
従って、後処理に能率の良い作業を実現させるには、
前記初期込物長D(m)の部分の何割かにも装薬を追加
して発破すれば、地表G.L付近の破砕、すなわち岩盤の
細分化が得られる。しかしながら、装薬の追加が過度に
なれば、今度は飛石による実害が発生して危険となり作
業そのものの遂行が困難となる。Therefore, to realize efficient work in post-processing,
If a charge is added to some of the portion of the initial inclusion length D (m) and blasted, crushing near the ground surface GL, that is, fragmentation of the bedrock can be obtained. However, if the charge is excessively added, actual harm due to the stepping stones occurs, which becomes dangerous and makes it difficult to perform the work itself.
本発明者は、多くの実施を重ねた結果、第2図で示す
ように、補助装薬量La(kg)は初期込物長D(m)の1/
2の長さを標準値Xa(m)とし、3/4の長さを安全限界値
Xb(m)とすれば、飛石による実害の危険がないことを
確認した。すなわち、前記実施例における初期込物長D
=7mの場合には標準値Xa点はその1/2、従って最終込物
長Daが3.5m、危険値Xb点は、D=7mの3/4、すなわち、
5.25mとなり、それ以下であれば作業の遂行が可能とな
る。このようにして得られた合計装薬量L+Laは穿孔長
H=14mの場合に、装薬長10.5mが標準装薬量値、12.25m
が安全限界値となる。The inventor of the present invention has conducted many experiments, and as a result, as shown in FIG. 2, the auxiliary charge amount La (kg) is 1 / the initial load length D (m).
The length of 2 is the standard value Xa (m), and the length of 3/4 is the safety limit
With Xb (m), it was confirmed that there was no danger of actual harm due to stepping stones. That is, the initial inclusion length D in the above embodiment.
In the case of = 7m, the standard value Xa is 1/2 of the standard value, and therefore the final inclusion length Da is 3.5m, and the danger value Xb is 3/4 of D = 7m, that is,
If it is less than 5.25 m, work can be performed. The total charge amount L + La obtained in this way is 10.5 m in the case of the perforation length H = 14 m, and the standard charge value is 12.25 m.
Is the safety limit.
なお、穿孔径rが細いほど、標準値Xa及び安全限界値
Xbは増加し、それが太い程減少する。The smaller the perforation diameter r, the more the standard value Xa and the safety limit value
Xb increases and decreases as it gets thicker.
g)発明の効果 以上詳述したように、本発明は、作業現場において、
まず最初に試験発破で爆破の影響が地表にあらわれる最
少装薬量Lにおける初期込物長Dを確認し、その価を基
礎にして、初期込物長Dの長さの3/4の長さに相当する
量の装薬を補助装薬量Laとして最少装薬量Lに追加し、
そのようにして得られた安全最多装薬量L+La(kg)で
穿孔発破を行なうようにした。従って、飛石による実害
の発生に至らない安全限界内において最多の装薬量を使
って爆破を行なうことができるので、作業の安全と能率
の双方が達成されるようになった。更に、前記初期込物
長Dの1/2の長さに相当する補助装薬量を最少装薬量に
加え、そのようにして得られた標準装薬量で爆破を施工
すれば、飛石が生じない安全な爆破が保証される。g) Effects of the present invention As described in detail above, the present invention
First, the initial load length D at the minimum charge L at which the effects of the blast appear on the ground surface during the test blasting is confirmed, and based on the value, 3/4 of the length of the initial load length D is determined. Is added to the minimum charge L as the auxiliary charge La,
Perforation blasting was performed with the maximum safety charge L + La (kg) thus obtained. Accordingly, since the blasting can be performed using the maximum amount of charge within the safety limit that does not cause actual damage due to the stepping stone, both safety and efficiency of the work have been achieved. Furthermore, if the auxiliary charge amount corresponding to a length of 1/2 of the initial inclusion length D is added to the minimum charge amount and the blasting is performed with the standard charge amount obtained in this manner, stepping stones are obtained. Safe blasting that does not occur is guaranteed.
第1図は、本発明方法の第1過程を示す説明図であっ
て、試験発破による爆破の影響が地表にあらわれる最少
装薬量Lによって破壊される岩盤の状態を例示する。 第2図は、本発明方法の第2過程を示す説明図であって
最少装薬量Lに補助装薬量Laを加えた安全最多装薬量L
+Laにて穿孔発破を行なう状態、及び、最少装薬量Lに
補助装薬量La′を加えた標準装薬量L+La′にて穿孔発
破を行なう状態を例示する。 H(m)……穿孔長、 l(m)……最少装薬長、 la,l′(m)……補助装薬長、 l+la(m)……安全最多装薬長、 l+l′(m)……標準装薬長 D(m)……初期込物長、 Da(m)……最終込物長、 L(kg)……最少装薬量、 La,La′(kg)……補助装薬量、 L+La(kg)……安全最多装薬量、 G.L……地表。FIG. 1 is an explanatory view showing a first step of the method of the present invention, and illustrates a state of a rock mass which is destroyed by a minimum amount of charge L that appears on the surface of the ground due to blasting caused by test blasting. FIG. 2 is an explanatory view showing a second step of the method of the present invention, wherein a safe maximum charging amount L obtained by adding the auxiliary charging amount La to the minimum charging amount L.
A state in which perforation blasting is performed with + La and a state in which perforation blasting is performed with a standard charge L + La ′ obtained by adding the auxiliary charge La ′ to the minimum charge L are illustrated. H (m): Perforation length, l (m): Minimum charge length, la, l '(m) ... Auxiliary charge length, l + la (m) ... Safety maximum charge length, l + l' (m ) Standard charge length D (m) Initial load length, Da (m) Final load length, L (kg) Minimum charge amount, La, La '(kg) Auxiliary Charge amount, L + La (kg): Maximum safe charge amount, GL: Ground surface.
Claims (2)
れる孔に装薬比重Aを有する所望の装薬量を入れて試験
発破を行なう場合に、 まず、その爆破の影響が地表にあらわれる規模の装薬量
を最少装薬量L、そのときの装薬長を最少装薬長lとし
て L=(π/4)r2・l・A そのときの込物長を初期込物長Dとして D=H−l を確認し、 次に、その初期込物長Dの3/4の長さを補助装薬長la、
すなわち、 la=(3/4)D とし、 その補助装薬長laに対応する補助装薬量Laを前記最少装
薬量Lに加えた合計装薬量L+La、すなわち、 L+La=(π/4)r2(l+la)A を安全最多装薬量とし、 その安全最多装薬量L+Laで穿孔発破を行なう、 ことを特徴とする穿孔発破における安全最多装薬量決定
方法。When a test blast is carried out by putting a desired charge amount having a charge specific gravity A into a hole formed by a desired perforation length H and a perforation diameter r, first, the effect of the blasting is reduced to the surface of the ground. Let L = (π / 4) r 2 · l · A be the initial charge length, where L is the minimum charge amount L and the charge length at that time is the minimum charge length l. Confirm D = H-I as D. Next, the length of 3/4 of the initial inclusion length D is set to the auxiliary charge length la,
That is, la = (3/4) D, and the total charge amount L + La obtained by adding the auxiliary charge amount La corresponding to the auxiliary charge length la to the minimum charge amount L, that is, L + La = (π / 4) ) R 2 (l + la) A is the maximum safe charge, and the maximum safe charge L + La is used for blasting. The method for determining the maximum safe charge in puncture blasting.
れる孔に装薬比重Aを有する所望の装薬量を入れて試験
発破を行なう場合に、 まず、その爆破の影響が地表にあらわれる規模の装薬量
を最少装薬量L、そのときの装薬長を最少装薬長lとし
て L=(π/4)r2・l・A そのときの込物長を初期込物長Dとして D=H−l を確認し、 次に、その初期込物長Dの1/2の長さを補助装薬長
l′、すなわち、 l′=(1/2)D とし、 その補助装薬長l′に対応する補助装薬量La′を前記最
少装薬量Lに加えた合計装薬量L+La′、すなわち、 L+La′=(π/4)r2(l+l′)A を標準装薬量とし、 その標準装薬量L+La′で穿孔発破を行なう、 ことを特徴とする穿孔発破における標準装薬量決定方
法。2. When a test blast is carried out by putting a desired amount of charge having a specific gravity A of charge into a hole formed by a desired perforation length H and a perforation diameter r, first, the effect of the blasting is reduced to the surface of the ground. Let L = (π / 4) r 2 · l · A be the initial charge length, where L is the minimum charge amount L and the charge length at that time is the minimum charge length l. Then, D = H−l is confirmed as D. Next, the length of half of the initial filling length D is set to the auxiliary charging length l ′, that is, l ′ = (1/2) D, The total charge amount L + La 'obtained by adding the auxiliary charge amount La' corresponding to the charge length l 'to the minimum charge amount L, that is, L + La' = (π / 4) r 2 (l + l ') A is standardized. A method for determining a standard charge amount in piercing blasting, wherein the blasting is performed with the standard charge amount L + La 'as the charge amount.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP29707788A JP2881179B2 (en) | 1988-11-24 | 1988-11-24 | A method for determining the safest maximum charge in perforation blasting. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP29707788A JP2881179B2 (en) | 1988-11-24 | 1988-11-24 | A method for determining the safest maximum charge in perforation blasting. |
Publications (2)
Publication Number | Publication Date |
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JPH02143100A JPH02143100A (en) | 1990-06-01 |
JP2881179B2 true JP2881179B2 (en) | 1999-04-12 |
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Application Number | Title | Priority Date | Filing Date |
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JP29707788A Expired - Fee Related JP2881179B2 (en) | 1988-11-24 | 1988-11-24 | A method for determining the safest maximum charge in perforation blasting. |
Country Status (1)
Country | Link |
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JP (1) | JP2881179B2 (en) |
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1988
- 1988-11-24 JP JP29707788A patent/JP2881179B2/en not_active Expired - Fee Related
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Publication number | Publication date |
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JPH02143100A (en) | 1990-06-01 |
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