CN113175855B

CN113175855B - Construction method for reducing underwater blasting noise

Info

Publication number: CN113175855B
Application number: CN202110340159.8A
Authority: CN
Inventors: 张冬洋; 徐小迟; 黄义刚; 冯莉; 曾柏瑞; 王冬; 秦坤; 李辛; 赵进; 邓世杰; 吕文婷; 张亚; 聂文龙; 丁小可; 汪凯; 邢跃; 徐青青; 李�浩; 胡拓
Original assignee: Changjiang Wuhan Waterway Engineering Co
Current assignee: Changjiang Wuhan Waterway Engineering Co
Priority date: 2021-03-30
Filing date: 2021-03-30
Publication date: 2023-01-24
Anticipated expiration: 2041-03-30
Also published as: CN113175855A

Abstract

The invention provides a construction method for reducing underwater blasting noise, which adopts single-sound time-delay continuous blasting, and improves blasting efficiency, reduces blasting construction times and reduces the occupied time of a navigation channel by the single-sound time-delay continuous blasting; under the condition of controlling the single-shot explosive quantity, the interval between every two explosions is adjusted through a detonating tube detonator delayed for 1 second, and the explosive quantities used between every two adjacent explosions are different, so that superposition resonance between every two adjacent explosions can be effectively prevented, and the explosive noise is controlled within the fishery protection threshold value; the wild animals are driven before blasting, and the interference of blasting noise to the wild animals can be effectively prevented.

Description

Construction method for reducing underwater blasting noise

Technical Field

The invention relates to the technical field of underwater blasting construction, in particular to a construction method for reducing underwater blasting noise.

Background

The underwater blasting refers to blasting under the water surface, the surface of underwater soil rock or the inside of an underwater rock stratum, and is generally used for reef blasting, navigation channel dredging, harbor deepening, foundation pit digging, groove digging, diversion tunnel forming and the like for civil use.

The main underwater noise of underwater blasting construction comes from underwater drilling blasting, the underwater drilling blasting generates strong shock wave noise in water, and marine organisms can be harmed due to excessive blasting noise. At present, the noise reduction of underwater blasting is mainly realized by limiting the single-section blasting explosive quantity to control the blasting noise, the single-section blasting explosive quantity is limited, multiple times of blasting construction are needed, the multiple times of blasting restrict the blasting construction efficiency, the operation cost is higher, the blasting efficiency can be improved by increasing the blasting explosive quantity, but the blasting noise is overlarge; due to the limitation of single-section priming explosive quantity, particularly blasting in a navigation channel, the blasting is carried out after the navigation channel is closed, and the operation of the navigation channel is influenced due to frequent operation; for the waters with rare marine organisms, the detonation is carried out for many times, the interference to marine animals and plants is increased, and the problem of increasing the environmental protection risk exists.

Disclosure of Invention

In view of this, the present invention provides a construction method for reducing underwater blasting noise, so as to solve the technical problem that it is difficult to reduce the blasting frequency on the premise of reducing noise.

The technical scheme of the invention is realized as follows:

the invention provides a construction method for reducing underwater blasting noise, which is used for reef blasting construction in coastal areas, adopts single-sound time-delay continuous blasting and comprises the following steps:

s100, determining single-shot blasting explosive quantity and time interval of two adjacent shots through an underwater blasting test, wherein the single-shot blasting explosive quantity is within 90kg, and the time interval of the two adjacent shots is 1 second;

s200, setting explosion points according to the distribution condition of the reefs, wherein each explosion point is provided with a plurality of sections, and each section is a sound;

s300, drilling each section according to a preset blasting point;

s400, carrying out charging and hole plugging operation on each section, wherein the blasting explosive quantity of each section is determined according to the blasting test result, and the blasting explosive quantities of two adjacent sections are different;

s500, connecting two adjacent sections of one explosion point through second delay detonating tube detonators, wherein each second delay detonating tube detonator is a 1 second delay detonating tube detonator;

s600, checking influence elements of underwater blasting noise;

s700, warning a clearing field and driving wild protection animals to a safe area;

s800, determining that no wild protection animal exists in the dangerous area of underwater blasting, and then performing underwater blasting construction;

and S900, after blasting is finished, checking and cleaning the blasting area.

On the basis of the above technical solution, preferably, the S100 includes the steps of:

s100, setting underwater blasting test points according to the distribution of reefs and recording the blasting explosive quantity of each sound;

s200, driving wild animals to a safe region of the blasting test point, and detonating the blasting test point after confirming that no wild animals exist in a dangerous region of the blasting test point;

s300, noise monitoring points are respectively arranged at different distances from the blasting test point and at different underwater depths;

s400, acquiring the noise value and the noise duration of each monitoring point according to the noise monitoring result;

s500, determining the single-sound blasting explosive quantity to be within 90kg according to the noise value of each monitoring point, determining the time interval between two adjacent sounds to be 1 second according to the noise duration of each monitoring point, and ending the test.

On the basis of the above technical solution, preferably, the safety area is away from the bursting point by 1500 m.

On the basis of the above technical scheme, preferably, in S200, the explosion point is provided with six sections, and adjacent two sections are connected by using 1-second delay detonator.

On the basis of the above technical solution, preferably, in S400,

s410, before charging, cleaning silt and stone chips in the holes;

s420, carrying out charging operation on each hole, wherein the charging operation adopts a medicine feeding rod to feed medicine, and the medicine poking operation is carried out to the bottom of each hole by using the medicine feeding rod;

and S430, after charging, plugging the hole by adopting broken stones with the length of less than 2cm, wherein the plugging length is not less than 0.5m.

On the basis of the above technical solution, preferably, the S600 includes the following steps:

s610, checking explosive columns extruded and deformed in the explosive carrying process;

s620, checking explosives which are not pasted with qualified certificates;

s630, checking the package of the second delay detonating primer with damage, and checking the second delay detonating primer without qualified delay detonating certification;

s640, carrying out water testing and deep water compression resistance monitoring on the second delay detonating tube detonator;

and S650, stopping working of the air compressor of the drilling ship during detonation.

On the basis of the above technical solution, preferably, in S650, the air compressor of the drilling ship stops working and leaves the blasting danger area, and the drill rod is lifted off the water surface when the drilling ship shifts.

On the basis of the above technical solution, preferably, the S700 includes the following steps:

s710, issuing a navigation closing forecast;

s720, driving the wild animals to a safe area far away from the blasting center by adopting a driving ship and a sound wall driving method;

and S730, driving the wild animals again by detonating the driving small cannon.

On the basis of the above technical scheme, preferably, in S730, two driving cannons are detonated, and the two driving cannons are detonated at intervals, wherein the interval time is 50 to 70 seconds.

On the basis of the above technical solution, preferably, in S900, after the blasting is finished, it is checked that there is a false blind shot in the blasting area, and if there is a blind shot, the processing should be immediately performed.

Compared with the prior art, the construction method for reducing the underwater blasting noise has the following beneficial effects:

(1) The blasting efficiency is improved, the blasting construction times are reduced, and the channel occupation time is reduced by single-sound delay continuous blasting; under the condition of controlling the single explosive quantity, the interval between every two explosions is adjusted through a detonating tube detonator delayed for 1 second, and the explosive quantities used between two adjacent explosions are different, so that superposition resonance between the two adjacent explosions can be effectively prevented, and the explosive noise is controlled within the fishery protection threshold value; the wild animals are driven before blasting, and the interference of blasting noise to the wild animals can be effectively reduced.

(2) Carrying out blasting test before blasting construction to determine the blasting explosive quantity and the time interval between two adjacent blasts, and reducing the possibility of errors during blasting construction so as to improve the safety of blasting construction; and driving wild animals to a safe area before the blasting test so as to reduce the interference of noise of the blasting test on the wild animals.

(3) The explosion point is provided with six sections to improve the explosion efficiency, and the two adjacent sections are connected by adopting a 1-second delay detonating tube detonator to prevent the two adjacent explosion from generating resonance.

(4) Before charging, cleaning up silt and stone chips in the hole to prevent the silt and stone chips from blocking the explosive; during charging, the operation of poking the explosive to the bottom of the hole is carried out, so that the explosion at the bottom of the hole is ensured, and the explosion quality is improved; after charging, broken stones with the length of less than 2cm are adopted for plugging the hole, the plugging length is not less than 0.5m, and the hole is plugged, so that the noise generated by blasting is reduced.

(5) Before detonating, investigate the influence key element of underwater blasting noise to guarantee that the blasting construction goes on smoothly, improve the security of blasting construction, furthest reduces the blasting noise, and the drilling ship air compressor stops can be by noise and the blasting noise difference that fire control branch air compressor machine produced and produces the stack resonance.

(6) When the drilling ship shifts, the drill rod is lifted away from the water surface so as to prevent the drill rod from scraping the blasting network.

(7) Before detonation, the method warns and clears away the field and drives the wild protection animals to a safe area, so that the blasting noise is prevented from influencing the wild animals.

(8) Two small driving cannons are adopted to drive wild animals, the two small driving cannons are detonated at intervals, and the interval time is 50-70 seconds, so that the wild animals are prevented from turning back.

(9) After blasting, the inspection blasting district has the blind big gun of mistake, if there is the blind big gun, should handle immediately, and the blind big gun has the risk of detonating, in time clears up to prevent that the blind big gun from causing harm to the wild.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a reef hole distribution diagram of the present invention;

FIG. 2 is a diagram of the arrangement of blasting points and monitoring points in the sea area of blasting of the present invention, in the morning;

FIG. 3 is a layout of the blasting sites and monitoring sites of the blasting sea area of the present invention-afternoon;

FIG. 4 is a schematic view of an equivalent cross section of the arrangement of monitoring points of the present invention in the morning;

FIG. 5 is a schematic view of an equivalent end surface of the monitoring point layout of the present invention, in the afternoon;

FIG. 6 is a schematic diagram of the blasting network wiring of the present invention;

FIG. 7 is a time-domain plot of the acoustic pressure measured at 10m depth by the hydrophone at the first monitoring point in the morning of the present invention;

FIG. 8 is a time-domain plot of the acoustic pressure measured at a water depth of 15m by the hydrophone at the first monitoring point in the morning, in accordance with the present invention;

FIG. 9 is a frequency domain plot of the acoustic pressure of the shock wave measured at 10m depth by the hydrophone at the first monitoring point in the morning of the present invention;

FIG. 10 is a time domain plot of the acoustic pressure measured at a water depth of 8m by a hydrophone at a second monitoring point in the morning, in accordance with the present invention;

FIG. 11 is a time domain plot of the acoustic pressure measured at 10m water depth by the hydrophone at the second monitoring point in the morning of the present invention;

FIG. 12 is a frequency domain plot of the acoustic pressure of the shockwave of a hydrophone at a second monitoring point in the morning at a depth of 10m, in accordance with the invention;

FIG. 13 is a time-domain plot of the acoustic pressure of a hydrophone at a third monitoring point in the morning at a depth of 2m, in accordance with the invention;

FIG. 14 is a time domain plot of the acoustic pressure measured at a water depth of 6m by a hydrophone at a third monitoring point in the morning, in accordance with the present invention;

FIG. 15 is a time-domain plot of the acoustic pressure measured at 10m water depth by a hydrophone at a third monitoring point in the morning, in accordance with the present invention;

FIG. 16 is a time-domain plot of the acoustic pressure measured at a water depth of 15m by a hydrophone at a third monitoring point in the morning, in accordance with the present invention;

FIG. 17 is a frequency domain plot of the acoustic pressure of the shock wave of a hydrophone at a third monitoring point in the morning at a depth of 10m, in accordance with the present invention;

FIG. 18 is a time domain plot of the acoustic pressure measured at 10m water depth by the hydrophone at the first monitoring point in the afternoon of the present invention;

FIG. 19 is a time domain plot of the acoustic pressure measured at a water depth of 12m by a hydrophone at a first monitoring point in the afternoon, in accordance with the present invention;

FIG. 20 is a frequency domain plot of the acoustic pressure of the shock wave measured at a water depth of 12m by a hydrophone at a first monitoring point in the afternoon, in accordance with the present invention;

FIG. 21 is a time domain plot of the acoustic pressure measured at 10m water depth by a hydrophone at a second monitoring point in the afternoon, in accordance with the present invention;

FIG. 22 is a sound pressure time domain plot of a hydrophone at a second monitoring point in the afternoon, measured at a water depth of 15m, in accordance with the invention;

FIG. 23 is a frequency domain plot of the acoustic pressure of the shock wave measured at a depth of 15m by a hydrophone at a second monitoring point in the afternoon, in accordance with the present invention;

FIG. 24 is a time-domain plot of the acoustic pressure measured at a depth of 2m by a hydrophone at a third monitoring point in the afternoon, in accordance with the present invention;

FIG. 25 is a sound pressure time domain plot at a water depth of 6m for a hydrophone at a third monitoring point in the afternoon, in accordance with the present invention;

FIG. 26 is a time domain plot of the acoustic pressure measured at 10m water depth by a hydrophone at a third monitoring point in the afternoon, in accordance with the present invention;

FIG. 27 is a time-domain plot of the acoustic pressure of a hydrophone at a third monitoring point, in accordance with the invention, taken at a depth of 15m in the afternoon;

FIG. 28 is a time domain plot of the shock wave sound pressure measured at 15m water depth by a hydrophone at a third monitoring point in the afternoon, in accordance with the invention;

fig. 29 is a schematic view of a reef blasting hole arrangement of the present invention;

FIG. 30 is a graph showing the prediction of the relationship between the sound pressure level of underwater explosion noise and the distance from the explosion point;

FIG. 31 is a time domain plot of measured acoustic pressure at a previous stage of the present invention;

FIG. 32 is a time domain plot of the acoustic pressure measured at a depth of 10m underwater at three monitoring points in the morning in accordance with the present invention;

fig. 33 is a sound pressure time domain plot measured at an underwater depth of 10m for three monitoring points in the afternoon of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The reef area of this embodiment is located in the main habitat of the white dolphin, the wild protection animal is mainly the white dolphin, the target animal of this blasting is the white dolphin, and for the sake of caution, the first blasting should be performed with a guard according to the safety distance (1500 m upstream and 1000m downstream) specified by the blasting safety regulations, in this embodiment, the safety distance is 1500m away from the blasting point. In order to avoid the influence of the explosion noise on the white dolphin, the explosion noise needs to be controlled to be 160dB within the limit value of fishery protection, namely the explosion noise which is 1500m away from the explosion point is less than 160dB. White dolphin driving measures are required before field blasting operation, the blasting explosive quantity must not exceed 136kg each time according to the requirement of an environmental assessment report, a construction area is located in a same-way channel, and white dolphin driving and sealing navigation are required before gas protection operation each time.

The construction method for reducing underwater blasting noise provided by the embodiment adopts single-sound time-delay continuous blasting, and the single-sound time-delay continuous blasting refers to single-sound time-delay multi-sound continuous blasting and comprises the following steps:

the single-shot blasting explosive quantity and the time interval of two adjacent shots of blasting are determined through an underwater blasting test, the preset single-shot blasting explosive quantity is not more than 90kg, the preset safe region is 1500m away from a blasting point, the noise threshold value of the boundary of the safe region is limited to 160dB, and meanwhile, the influence of blasting noise on a coastal building is also tested.

Setting underwater blasting test points according to the distribution of reefs and recording the blasting amount of each ring, determining the distance between the blasting test points and the coast to be a, setting three monitoring points according to the positions of the blasting test points, wherein the three monitoring points are a first monitoring point, a second monitoring point and a third monitoring point respectively, and the first monitoring point monitors a dangerous area (the preset dangerous area is 300m away from the blasting points); the second monitoring point corresponds to the distance of the coast and is used for monitoring the building influence of the blasting noise on the coast; the third monitoring point is close to the safety zone, and whether the noise of the safety zone is smaller than a threshold value is monitored; the distance between the first monitoring point and the blasting test point can be set to be 0.2 a-0.3 a, the distance between the second monitoring point and the blasting test point can be set to be 0.8 a-0.9 a, and the distance between the third monitoring point and the blasting test point can be set to be 900-1200 m. The blasting test includes twice, and two blasting tests are gone on at morning and afternoon in one day respectively, and is specific, and the blast point of two blasting tests is all inequality, and the blast point of morning blasting test is apart from coast 500m, and the blast point of afternoon blasting test is apart from coast 380m.

In the morning blasting test, as shown in fig. 2 and 4, the first monitoring point is 100m away from the morning blasting test point, two hydrophones are arranged under the water of the first monitoring point, and the two hydrophones are respectively located at the positions of 10m and 15m of the underwater depth of the first monitoring point. The second monitoring point is 410m away from the morning blasting test point, two hydrophones are arranged under the water of the second monitoring point, and the two hydrophones are respectively positioned at the underwater depth of 8m and 10m of the second monitoring point. The third monitoring point is 1150m away from the morning blasting test point, four hydrophones are arranged under the water of the third monitoring point, and the four hydrophones are respectively positioned at the underwater depths of 2m, 6m, 10m and 15m of the third monitoring point. Hydrophones are used to monitor noise duration, noise level, and noise propagation.

In the blasting test in the afternoon, as shown in fig. 3 and 5, the first monitoring point is 90m away from the blasting test point in the afternoon, two hydrophones are arranged at the underwater depth of the first monitoring point, and the two hydrophones are respectively located at the underwater depths of 10m and 12m of the first monitoring point. The second monitoring point is 330m away from the afternoon blasting test point, two hydrophones are arranged under the water of the second monitoring point, and the two hydrophones are respectively positioned at the underwater depth of 10m and 15m of the second monitoring point. The third monitoring point is 960m away from the afternoon blasting test point, four hydrophones are arranged underwater at the third monitoring point, and the four hydrophones are respectively positioned at the underwater depths of 2m, 6m, 10m and 15m at the third monitoring point.

As shown in fig. 6, the blasting test is set to six sections, one section for each hole is 2, 3, 4, 5, 6 and 7 sections, and 1 section of instantaneous (without delay) detonating tube detonators is adopted for wiring. The explosive dosage of each section is respectively as follows: in the morning, 66kg, 63kg, 69kg, 72kg, 57kg and 69kg, amounting to 392kg; in the afternoon, 81kg, 84kg, 87kg, 78kg, 81kg and 78kg, amounting to 489kg. The explosive can be selected from waterproof emulsion explosive, the initiator can be selected from an electric spark initiator, six sections are arranged at the explosion point to improve the explosion efficiency, and the adjacent two sections are connected by adopting a 1-second delay detonating tube detonator to prevent the adjacent two explosions from generating resonance. The single-section priming explosive quantity can also be distributed according to small, large and medium sizes. Before the blasting test, the wild animals are driven to the safe region of the blasting test point, and the blasting test point can be detonated after the condition that no wild animals exist in the dangerous region of the blasting test point is confirmed.

The method for repelling wild animals comprises the following steps: no. 8 non-electric detonators with unit drug loading of 0.8g are used as materials for driving small cannons, and the driving small cannons are arranged in a range of 100m away from a blasting test point by a construction ship. Two driving small cannons can be selected, the two driving small cannons are distributed at different underwater depths, one driving small cannon is distributed at a position 20-30 cm far away from the seabed in the water, and the other driving small cannon is distributed at a position half the water depth in the water. The two small driving cannons can drive marine animals from different underwater depths, and one small driving cannon is close to the seabed, so that the marine animals are prevented from hiding into the seabed, and the driving effect is improved. The two driving small cannons are detonated at intervals, and the interval time is usually 50-70S.

The driving ship drives the wild animals to the safe region of the blasting of the small gun, the small gun is ignited and driven after confirming that the dangerous region of the blasting of the small gun has no wild animals, the time interval of the ignition of the small gun and the ignition of the blasting test point is confirmed, and the blasting test point is ignited after a period of time. Two driving small cannons are detonated at intervals, the detonation time interval of the two driving small cannons is 50-70S, resonance generated when the two driving small cannons detonate can be effectively prevented, and target animals or other marine animals can be prevented from turning back after the first driving small cannon detonates. And drilling the underwater blasting test point by adopting an air compressor drilling construction ship, and closing the air compressor before driving the small cannon to detonate.

TABLE 1 position of each monitoring point and hydrophone layout depth

The monitoring results plotted according to the results of the underwater blasting test are as follows:

TABLE 2 monitoring results of monitoring points-morning

TABLE 3 monitoring results of monitoring points-afternoon

Fig. 7-28 are time-domain diagrams of sound pressure measured by the hydrophone at different depths under water.

Before the field blasting test, the background noise of the blasting area is synchronously monitored, and the monitoring results of the background noise of the blasting area in the morning and afternoon are shown in the following table:

TABLE 4 ocean background noise monitoring results for construction-morning

TABLE 5 ocean background noise monitoring results of construction-afternoon

Comparing underwater noise sound pressure spectrum levels before blasting and during blasting, and comparing average sound pressure spectrum levels obtained by different monitoring points at the same depth (underwater 10 m) during six-section underwater blasting with a sound pressure spectrum level value of the background noise in the sea area during non-blasting construction, wherein the results in the morning and the afternoon are shown in the following table:

TABLE 6 comparison of Underwater noise sound pressure spectra levels at blasting and non-blasting-AM Unit (dB/1 uPa)

TABLE 7 comparison of Underwater noise Sound pressure spectra levels at blasting and non-blasting-afternoon units (dB/1 uPa)

According to the relation that the noise transmission changes along with the distance, and according to the threshold value standard and the sound pressure time domain diagram of each monitoring point, the prediction of the influence distance of the dolphin in Chinese white is given, and the prediction diagram is shown in fig. 30.

TABLE 8 Underwater Brill explosion noise sound pressure level distribution

TABLE 9 prediction of influence distance of underwater blasting noise sound pressure level on dolphin in China white

As can be seen from fig. 30 and table 9, the predicted distance is 289m, which is smaller than 300m; the warning area is 1028 meters and less than 1500m, and the interference of blasting noise to wild animals can be effectively reduced except that the wild animals are driven to 1500 m.

The resonance requirement of two-shot blasting is tested in the early stage, and noise monitoring is performed in the early stage under the condition that the single-section blasting explosive quantity is controlled to be 90kg, as shown in fig. 31, a sound pressure time domain diagram (distance 285m from a blasting point) measured by a hydrophone at the early stage at positions of 3m and 10m is obtained, the blasting noise blasting duration is less than 120ms, and the peak value duration is short. The single-sound delay continuous blasting mode is adopted for operation, when the time interval of two blasting exceeds a certain (about 120 ms) interval, the blasting noise does not have the condition of superposition resonance, and the noise cannot be obviously increased. The noise can be controlled within the threshold value specified by fishery protection theoretically by adopting a multi-sound delay continuous explosion mode.

The water impact wave generated by underwater explosion is superposed with hydrostatic pressure, so that the pressure change process at a certain fixed position underwater can be increased to peak pressure at the moment of microsecond magnitude. But for a short duration, the pressure begins to decay exponentially with time after the initial peak pressure has reached. Within a few milliseconds, the pressure value drops rapidly.

When blasting in an underwater borehole, energy is transmitted in the water mainly in the form of water shock waves, and the peak pressure of the generated shock waves is weakened along with the distance from a blasting source.

The water depth of the blasting sea area is about 18m, the shock wave in the water is reflected from the sea surface to form a negative pressure area, the shock wave is reflected from the surface of the sea to form a positive pressure area, and the wave form of the shock wave is continuously expanded and prolonged along with the increase of the distance from the blasting source.

Compared with the sound pressure spectrum level of the ocean background noise before drilling explosion, the monitoring result of the morning shows that the underwater noise spectrum level of the sea area is improved by about 36-50 dB (36-57 dB in the afternoon) in a wider frequency range (20 Hz-20 kHz) at a position 100m away from the drilling explosion point by the underwater drilling explosion. At a position 410m away from a blast point, the underwater drilling blast improves the spectrum level of the underwater noise in the sea area by about 18-37 dB in a wider frequency range (20 Hz-20 kHz) (the afternoon result is 20-31 dB). At the position 1150m away from the drilling and blasting point, the underwater drilling and blasting of the time enables the spectrum level of the underwater noise in the sea area to be improved by the magnitude order of nearly 18-29 dB (the afternoon result is 3-35 dB) in a wider frequency range (20 Hz-20 kHz).

In the test, the noise duration time t1 of a first monitoring point, the noise duration time t2 of a second monitoring point and the noise duration time t3 of a third monitoring point are obtained; determining the initiation time interval T of two adjacent rings, wherein T is more than T1+120ms, T is more than T2+120ms, and T is more than T3+120ms; and if the noise root mean square sound pressure level of the noise value of the third monitoring point is more than 160dB, determining the explosive quantity of the blasting test. As shown in fig. 32 and 33, the noise durations for the three monitoring points are each less than 500ms. The millisecond differential time between each section of the current underwater drilling blasting is set to be 1.0s, and from the blasting time domain diagram obtained by measurement, as shown in fig. 32 and 33, the time intervals between each section of direct waves are uneven. Although the predetermined differential interval is not reached, there is no significant superimposed increase in the blasting noise. Therefore, 1-second delay nonel detonator can be selected for blasting construction, the 1-second delay nonel detonator is enough, the interval between two adjacent rings for blasting is about 500ms, and in order to improve the blasting efficiency, the blasting explosive quantity of each section is not too small and is 55-90 kg.

Carrying out blasting test before blasting construction to determine the blasting explosive quantity and the time interval of two adjacent blasts, reducing the possibility of error during blasting construction and improving the safety of blasting construction; and driving wild animals to a safe area before the blasting test so as to reduce the interference of noise of the blasting test on the wild animals.

Setting explosion points according to the distribution condition of the reefs, wherein each explosion point is provided with a plurality of sections, and each section is a sound; six sections can be set according to the blasting test result, one section in each hole is 2 sections, 3 sections, 4 sections, 5 sections, 6 sections and 7 sections, and 1 section of instantaneous (non-delay) detonating tube detonator is adopted for wiring. The explosive dosage of each section can be determined according to the test result, namely the explosive dosage of a single section is 55-90 kg, and the blasting network diagram on the reef is shown as figure 1.

And drilling each section according to a preset blasting point, and drilling to the designed hole bottom elevation (including the depth of the ultra-drilling) at one time by adopting a down-the-hole percussion drill, wherein the hole is distributed in a quincunx manner. The down-the-hole percussion drill can be firmly installed on a workbench of a construction ship, and a GPS point can be placed on a hole position. The drill rod is firmly installed, and the phenomenon of rod falling or sliding rod is prevented. Performing composite encryption on the elevation control points and the coordinate control points before drilling; the down-hole blasting is preferably carried out by drilling once to the designed bottom elevation of the blast hole, and the blasting sequence is carried out from deep water to shallow water and from downstream to upstream. The drilling holes are not influenced by water flow to generate dislocation and deflection. The drilling ship is stable, and the positioning is accurate and is checked frequently; deviation of the drill hole position: inland river should be less than 20cm, coastal should be less than 40cm, as shown in fig. 29, it is a schematic diagram of reef blasting hole distribution. Or a lifting rope is tied at the position of 1.0-1.5 m of the base pin of the sleeve, the rope head is pulled to the upstream part, a specially-assigned person carries out nursing, the conductor orders to slowly relax along with the sinking of the sleeve until the sleeve is positioned, then the rope is taken off, and the drill rod is put down to carry out drilling operation. When the drilling ship shifts, the drill rod is lifted away from the water surface so as to prevent the drill rod from scraping the blasting network.

And after drilling, loading and plugging each section, determining the blasting explosive quantity of each section according to the blasting test result, wherein the blasting explosive quantities of two adjacent sections are different. Before charging, the mud sand and stone chips in the hole are blown clean, and whether the hole depth meets the requirement or not is measured; the initiating explosive is processed on site, a specially-made circular plastic cylinder is adopted for charging explosive columns, the diameter of each explosive column can be 120mm, and the explosive is rock emulsion explosive or seismic explosive column with strong waterproofness and good explosion performance. And after the processing is finished, the materials are immediately loaded into the holes. During medicine charging, the medicine package lifting rope is pulled stably and matched with the medicine feeding rod, and the medicine package clamped in the hole is not forced to impact and extrude: the deep water blasting adopts a bamboo pole as a powder feeding pole. When the underwater deep hole adopts the sectional charging in the hole, the sections should be filled at intervals: when the delayed blasting is adopted in the hole, the filling length is not less than the sympathetic detonation distance of the explosive. The underwater drilling blasting is filled with crushed stone or coarse sand and crushed stone mixture with the filling length of less than 2.0cm, and the filling length is not less than 0.5m.

Before charging, cleaning up silt and stone chips in the hole to prevent the silt and stone chips from blocking the explosive; during charging, the operation of poking the explosive to the bottom of the hole is carried out, so that the explosion at the bottom of the hole is ensured, and the explosion quality is improved; after charging, broken stones with the length of less than 2cm are adopted for plugging the holes, the plugging length is not less than 0.5m, the holes are plugged, and noise generated by blasting is reduced.

The underwater drilling blasting adopts a delayed priming circuit, and a second delayed detonating tube detonator is suitable to be put into a hole: the monitoring is that the engineering adopts underwater drilling and blasting construction with different dosages, the underwater drilling and blasting adopts 1 second time delay interval time, the actual effect can reach 400-1000 ms, the millisecond delay pre-splitting between holes or rows is carried out, and the blasting is carried out hole by hole; two driving small cannons (non-conductive blasting caps adopted in water) can be added before drilling explosion so as to achieve the purpose of warning and driving the Chinese white dolphin in advance. When the delay detonating circuit is used, measures should be taken to protect the detonating circuit. One section is arranged in each hole, two adjacent sections of one explosion point are connected through a second delay detonating tube detonator, and the second delay detonating tube detonator is a 1 second delay detonating tube detonator.

The method for investigating the influence factors of underwater blasting noise specifically comprises the following steps: the constructor needs to train and then carry out construction operation after the constructor is on duty and checks the explosive columns extruded and deformed in the explosive carrying process; checking explosive which is not pasted with qualified certification, checking the package of the damaged second delay detonating primer, checking the second delay detonating tube primer without the qualified certification of delay detonating, testing water and monitoring deep water compression resistance of the second delay detonating tube primer, and monitoring the compression resistance and the water resistance of the detonator which is fed in batch before the first construction. And the air compressor of the drilling ship stops working when detonating.

Before the detonation, influence factors of underwater blasting noise are checked to ensure that blasting construction is smoothly carried out, the safety of blasting construction is improved, blasting noise is reduced to the greatest extent, and the air compressor of the drilling ship stops and can generate superposition resonance by the difference of noise generated by the fire fighting branch air compressor and the blasting noise.

And (5) warning and clearing the field, driving wild protection animals to a safe area, and issuing a navigation-sealing forecast.

Driving wild animals to a safe area far away from a blasting center by adopting a driving ship and a sound wall driving method, wherein two driving small guns are arranged in a range of 100m away from a blasting point and are respectively arranged at different underwater depths, the driving small guns are made of 8-number non-electric detonators with unit drug loading of 0.8g, and are respectively a first driving small gun and a second driving small gun; the first driving small cannon is arranged in the position 20-30 cm away from the sea bottom in the water, so that wild animals close to the sea bottom can be effectively driven; the second driving small cannon is arranged at a position with half water depth in water, the two driving small cannons are detonated at intervals, the interval time is 50-70 seconds, so that the wild animals are prevented from turning back, and the two driving small cannons are arranged to drive the wild animals in an all-round mode.

Before the small gun is detonated and driven, fixed-point observation points are required to be arranged at the upper and lower reaches of a construction area, and trained observers are entrusted to observe and make records of the activity of the dolphin in the construction area every day.

Since the swimming animals of the genus dolphin are actively avoided when they are disturbed by external factors. For continuous blasting, the white dolphin will quickly escape from the blasting area, except that the first shot blasting will have a greater effect on the white dolphin in the near blasting area, and the other shots will have a relatively smaller effect on the self dolphin. By adopting necessary environmental protection measures, such as enhancing the observation and understanding of the construction sea area, driving by sound walls and other various methods, the influence on the white dolphin can be greatly reduced.

And after the small driving cannons are arranged, a sound wall driving method is adopted to drive the dolphin with the Chinese white dolphin. The sound wall driving method is to utilize the echo positioning function of Chinese white dolphin to drive Chinese from staying in dolphin or prevent it from entering blasting dangerous area by means of artificial sound wall. The specific method comprises the following steps: on the two sides of the ship board of the driving ship, bamboo poles with the length of 2m and the diameter of 30-50 mm are arranged every 0.5-1 m, and telescopic rods can also be adopted, and the bamboo poles can be inserted into water by 20-40 cm. The number of the bamboo poles is determined according to the length of the ship, generally about 7, the upper end and the lower end of each bamboo pole are connected with transverse poles, and the transverse poles connect the bamboo poles in a row. After the driving is finished, 4 driving ships are outwards arranged in a fan shape from the explosion point, the driving ships run slowly by adopting an S-shaped line, a specially assigned person on the driving ships beats the driving ships from the first bamboo pole to the last bamboo pole, then the driving ships beat the bamboo poles in a reciprocating mode by a procedure that the driving ships beat the driving ships from the last bamboo pole to the first bamboo pole, the ship speed is continuously changed, irregular noise is produced, and a continuous sound wall is formed. A driving mechanism can also be arranged on the ship, and the driving mechanism drives the knocking stick to knock the bamboo pole, so that the labor is saved. The ship can be stopped after being opened about 1600-2000 m beyond the explosion point, and the bamboo poles are continuously and transversely beaten until the explosion is finished, so that the wild animals are prevented from turning back. And in the process that the construction ship exits from the safe area and is ready for detonation, the whistle warning is driven. And (3) detonating and driving the small cannons if no wild animals exist in the blasting dangerous area, adopting two driving small cannons to drive the wild animals, and detonating the two driving small cannons at intervals of 50-70 seconds to prevent the wild animals from turning back and ensure that no wild animals exist in the blasting dangerous area.

Before detonation, a specially-assigned person must be sent to watch on the driving ship and the construction ship, if the white dolphin is found to appear in a construction sea area, the detonation should be stopped immediately, an interphone is used for being in contact with a person in charge of a construction site, driving measures are formulated, the white dolphin in China is driven, and the detonation cannot be carried out until the white dolphin is driven away from a blasting center by 1500 m. Before detonation, the method warns and clears away the field and drives the wild protection animals to a safe area, so that the blasting noise is prevented from influencing the wild animals.

Each time of detonation, a construction technician must record the explosive amount, the driving condition and the sea condition after detonation. After blasting is finished, a blaster must carefully check whether blind shots exist in a blasting area according to regulations, and when the blind shots are found or suspected, the blind shots are immediately reported and timely processed. After blasting, the inspection blasting district has the blind big gun of mistake, if there is the blind big gun, should handle immediately, and the blind big gun has the risk of detonating, in time clears up to prevent that the blind big gun from causing harm to the wild.

The single-sound delayed continuous blasting is adopted, so that the blasting efficiency is improved, the blasting construction times are reduced, and the channel occupation time is reduced; under the condition of controlling the single explosive quantity, the interval between every two explosions is adjusted through a detonating tube detonator delayed for 1 second, and the explosive quantities used between every two adjacent explosions are different, so that the vibration frequencies of the two adjacent explosions are different, the superposition resonance generated between the two adjacent explosions can be effectively prevented, and the explosive noise is controlled within the fishery protection threshold value; the wild animals are driven before blasting, and the interference of blasting noise to the wild animals can be effectively prevented.

Through testing underwater blasting, the noise generated by different explosive quantities underwater and the propagation condition are mastered, and the safety of construction is proved by data. Through testing data, the reliability and the scientificity of the scheme are improved for the formulated noise reduction measures, the selected blasting materials and the formulated blasting process, and the construction safety and the environmental protection risks are effectively reduced. According to the technical scheme, the blasting construction efficiency is effectively improved, the project construction period is shortened, and the cost is saved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A construction method for reducing underwater blasting noise is characterized in that the method is used for reef blasting construction in coastal areas, single-sound time-delay continuous blasting is adopted, and the method comprises the following steps:

s100, determining single-shot blasting explosive quantity and time interval of two adjacent shots through an underwater blasting test, wherein the single-shot blasting explosive quantity is within 90kg, and the time interval of the two adjacent shots is 1 second; which comprises the following steps: s110, setting underwater blasting test points according to the distribution of reefs and recording the blasting explosive quantity of each sound; s120, driving the wild animals to a safe region of the blasting test point, and detonating the blasting test point after confirming that no wild animals exist in the dangerous region of the blasting test point; s130, noise monitoring points are respectively arranged at different distances from the blasting test point and at different underwater depths; s140, acquiring the noise value and the noise duration of each monitoring point according to the noise monitoring result; s150, determining the single-sound blasting explosive quantity to be within 90kg according to the noise value of each monitoring point, determining the time interval between two adjacent sounds to be 1 second according to the noise duration of each monitoring point, and ending the test;

s300, drilling each section according to a preset blasting point;

s400, carrying out charging and hole plugging operation on each section, wherein the blasting explosive quantity of each section is determined according to a blasting test result, and the blasting explosive quantities of two adjacent sections are different;

s500, two adjacent sections of one explosion point are connected through a second delay nonel detonator, and the second delay nonel detonator is a 1-second delay nonel detonator;

s600, checking influence factors of underwater blasting noise;

and S900, after blasting is finished, checking and cleaning the blasting area.

2. The method of claim 1, wherein the safe area is located at a distance of 1500m from the detonation point.

3. The construction method for reducing noise of underwater blasting according to claim 1, wherein in S200, the blasting point is provided with six sections, and adjacent two sections are connected by a 1-second delay detonator.

4. The underwater explosion noise reduction construction method according to claim 2, wherein in S400,

s410, before charging, cleaning silt and stone chips in the holes;

s420, carrying out powder charging operation on each hole, wherein the powder charging operation adopts a powder feeding rod to feed powder, and poking the powder to the bottom of each hole by using the powder feeding rod;

5. The underwater explosion noise reduction construction method according to claim 4, wherein the S600 comprises the steps of:

s620, checking explosives which are not pasted with qualified certificates;

6. The underwater explosion noise reduction construction method according to claim 5, wherein in S650, an air compressor of the drill ship stops and leaves the explosion danger area, and the drill pipe is lifted off the water surface when the drill ship is shifted.

7. The underwater blasting noise reduction construction method according to claim 2, wherein the S700 includes the steps of:

s710, issuing a navigation closing forecast;

8. The underwater explosion noise reduction construction method according to claim 7, wherein two driving cannons are detonated in the step S730, and the two driving cannons are detonated at intervals of 50 to 70 seconds.

9. The underwater blasting noise reduction construction method according to claim 1, wherein in S900, after blasting is finished, whether blind shots exist in a blasting area is checked, and if blind shots exist, the blind shots are immediately processed.