JPS62261900A - Method of blasting construction - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a blasting method including a detonation method that uses interference to reduce the imaging that occurs during blasting.

[Conventional technology] Conventionally, when blasting is to be carried out near structures or urban areas, it has been necessary to reduce the amount of explosives per hole and perform multi-stage blasting using set electric detonators. It was coming.

Furthermore, in bench blasting and the like, attempts have been made to use DS electric detonators instead of MS electric detonators, and to take advantage of the variations in surrounding installation to reduce the exposure. Roughly speaking, at tunnel sites, in 8-center blasting where the imaging is large, MS stages (approximately MS-3 stages) are used instead of instantaneous blasts, and vibrations can be suppressed due to the variations in the MS stages. known from experience.

[Problem to be solved by the invention 1 However, since the conventional setting electric detonator (using a time-delaying charge) has a limit to its time accuracy, attempts have been made to reduce the 1-stroke by taking advantage of the dispersion. However, this was not always successful, and sometimes they even grew larger, making it difficult to control.

Furthermore, when trying to perform multi-stage blasting in order to reduce one stroke, the conventional settings were limited to around 30 stages, which reached the limit for further division into multiple stages.

[Means for Solving the Problems] In order to solve the above problems, the inventors developed an electric delay detonator with good time precision, for example, in Japanese Patent Application Laid-Open No. 57-14.
Using the devices known from No. 298 and JP-A No. 58-83200, we succeeded in developing a blasting method that takes advantage of their high accuracy.

In other words, by loading and detonating electrically delayed electric detonators having a fixed time interval in seconds into a plurality of holes, the vibration waves generated in the hole can be suppressed by setting the detonation time of the plurality of holes in the blasting operation to a fixed interval in seconds. This is a blasting method that reduces the amount of photography that occurs during blasting work by interfering with other materials.

[Function] It is known that the imaging caused by blasting is a single vibration, and that the imaging frequency is about tens to hundreds of 8Z at distances where imaging of blasting becomes a problem. However, the size and feel of the image will vary depending on the ground conditions at the receiving point, so the predominant vibration frequency at the receiving point is measured in advance, and then a constant second-time interval smaller than the required vibration period is taken. By detonating multiple holes at the same time, the vibrations of the holes weigh and interfere with each other, making it possible to reduce the vibration speed and reduce the photographic value.

Furthermore, the time interval between seconds is relatively short (several to several tens of meters)
), multi-stage blasting (30
dan or higher) is now possible.

[Example] Hereinafter, the blasting method of the present invention will be specifically explained using Examples and Experimental Examples.

First, the following experiment was conducted to confirm the effects of the present invention.

In Experimental Example 0, an electric delay detonator was attached to a hydrous explosive (trade name: Sanpex) 100 (), and three bombs were placed at 1 m intervals at a depth of 0.5 m.
A book was set, the second time interval was changed, and the commotion was measured at a concrete structure and a pillar of a building at a distance of 50 m.

As a comparative example, we would also like to measure the imaging when three blasters were fired at the same time using instantaneous electric detonators (Table 1: 3 blanks).

The results are shown in Table-1. Furthermore, the results of imaging and frequency measurement for only one hole are shown in Table 1 (blank 17K) and Table 2.

Table 1 Unit (cm/s) Table 2 From these results, it can be seen that compared to multi-hole simultaneous firing, detonation using an electrically delayed electric detonator with a period of 273 seconds will minimize the imaging speed. .

Example 1 In a quarry mountain with a bench height of 21 m, 50 to 1
When the imaging frequency was measured at 50m point, it was 37H.
It was 2. So, we put 100k of unho explosive into 5 bench holes with hole diameter 65mmφ, hole length 18m, hole distance 6m, and resistance wire 4m.
(] / Hole and 3 paulownia dynamite was equipped with an electric delay detonator set at a time interval of 15m5 and detonated at 50~1
The shooting was measured at a distance of 50 m. In addition, for comparison, as a conventional method, the conventional setting electric detonator (25 mS) 1 to 5
Measurements using stages were also carried out.

The results are shown in Table-3.

Table 3 (Unit: cm/s) In this case, from the frequency 37H2 (the commotion period is 27m5, the second time interval of 15m5, which is about half of that, is 25cm/s).
It was possible to reduce the distance to about 30-70% of the m5 interval.

Example 2 In a limestone mountain with a bench height of 15 m, the hole diameter was 165 mmφ
, hole length 18m, hole spacing 6m, resistance wire 41T! Anho explosives 170k (1/hole, electric delay detonators were installed on 3 paulownia as main guide), 100-15k from the face.
Blasting at 0m point] The disturbance was measured. In addition, as a conventional method, similar blasting was performed using 4 to 10 stages of DS electric detonators, and the imaging was measured.

Here, the imaging frequency measured in advance in a single shot is l0
Hz, the second time interval of the present invention has a period of 100
It was set to 15m5, which is approximately 176 m5.

The results are shown in Table-4.

Table 4 (unit: cm/s) Furthermore, the imaging waveform is shown in the attached drawing. FIG. 1 shows the three-phase waveform of the second embodiment of the present invention, and FIG. 2 shows the conventional method (D
This is the photographed waveform of S).

As can be seen from these results, it can be seen that with the method of the present invention, the vibration value is small in all cases, and the time is shorter than that of the DS electric detonator.

[Effects] As is clear from the above examples, when the blasting method of the present invention is used, it is possible to reduce the amount of shooting without reducing the blasting effect by keeping the amount of charge the same as that of the conventional method. therefore,(
Blasting can be carried out without reducing work efficiency at sites where commotion is a problem, improving overall efficiency, predicting blasting vibrations, and managing blasting operations.

[Brief explanation of drawings]

FIG. 1 shows an imaging waveform of a second embodiment of the present invention, and FIG. 2 shows a vibration waveform of a conventional method described in the second embodiment.

Claims (1)

[Claims] A blasting method characterized by reducing the vibrations generated during blasting work by setting the detonation time of multiple holes in the blasting work at regular intervals of seconds and utilizing the interference of the vibration waves generated in each hole.