Urban sensitive area hard rock vertical shaft shock absorption and noise reduction blasting construction method

Abstract

The application discloses a kind of urban sensitive area hard rock shaft shock absorption and noise reduction blasting construction methods. Including the following steps: step 1, install sound insulation and noise reduction closed greenhouse;Step 2, blasting free face;Step 3, drilling;Step 4, shock hole;Step 5, charge;Step 6, network connection: step 7, cap: step 8, in the case of large section, adopt partitioned blast way, the application effectively reduces the influence on daily life of residents;Effectively solve the problem of hard rock rotary drilling hole difficulty;Reduce the damage of blasting to surrounding rock, improve the stability of surrounding rock and can play a shock absorption effect;Adopt single-hole single-response hole micro-delay blasting technology, neither will produce subsequent blasting hole shock wave superposition, nor will occur due to blasting hole explosion damage subsequent blasting hole foot line problem to improve blasting quality;In surrounding hole, water column interval charging is beneficial to improve blasting effect and can reduce blasting vibration and reduce dust.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of building engineering, and particularly relates to a hard rock vertical shaft shock absorption and noise reduction blasting construction method in a city sensitive area. BACKGROUND

[0002] When constructing underground projects in urban areas, the surrounding environment of urban construction is complex, there are many operating subway lines and various comprehensive pipelines, especially hospitals, schools, gas pipelines, operating subways and C-class buildings, which are sensitive to blasting vibration, and the design vibration speed control value is 0.5cm / s-1.5cm / s; the daily life of residents in the surrounding residential area is disturbed. In addition, the construction progress is relatively slow due to the influence of hard rock construction difficulties, the vibration of hard rock construction machinery crushing excavation is small, the construction progress is slow, the noise duration is long, the blasting construction vibration is large, the short-time noise is large, and the health of the construction personnel is also affected. Therefore, it is necessary to study the hard rock vibration reduction and noise reduction blasting excavation method, which not only accelerates the vertical shaft excavation construction progress, but also reduces the influence of blasting construction on the surrounding environment.

[0003] In the prior art, Chinese invention patent application No. 202210946221.2 discloses a city tunnel shock absorption blasting structure and construction method, which comprises a blasting excavation section and a blast hole arranged on the blasting excavation section, an explosive assembly is placed in each blast hole, the explosive assembly comprises a digital electronic detonator, the digital electronic detonator comprises a directional energy concentration sleeve and an explosive located in the directional energy concentration sleeve; the blast hole comprises a pre-splitting hole, the pre-splitting hole comprises a plurality of first pre-splitting holes, the connecting line of the circular centers of the plurality of first pre-splitting holes is a first circular arc, the pre-splitting hole further comprises a plurality of second pre-splitting holes, the connecting line of the circular centers of the plurality of second pre-splitting holes is a second circular arc, the second circular arc is located above the first circular arc, and the first circular arc and the second circular arc form a pre-splitting shock absorption zone.

[0004] In addition, Chinese invention patent application No. 202111426316.3 discloses a construction method for shock absorption blasting of urban underground space, comprising the following steps: A. Before foundation pit excavation blasting, first dig a construction slot around and make a good enclosure structure; B. According to the surrounding environment, topographic condition factors, the entire blasting area is constructed by three different methods, the first method is to use static crushing method for the blasting area within 30 m from the residential building, 3 m from the enclosure structure and column, the second method is to use shallow hole loose control blasting construction for the area with blasting depth less than 5 m, land modification and bottom root treatment, and the third method is to use deep hole weak loose control blasting construction for the area with blasting depth greater than 5 m; C. Use the construction slot to arrange blast holes in the area that needs to be blasted first, the blast holes are arranged in a quincunx pattern, 3-5 rows of blast holes are arranged each time, the number of blast holes is determined according to the foundation pit working face site, and the depth of the blast hole, the standoff distance of each blast hole in the front row, and the water content in the hole are checked; D. After the blast holes are arranged, each blast hole is charged, including detonator foot line, backfilling of blast hole clay, emulsion explosive and electronic detonator, the foundation pit blasting uses a continuous columnar charging structure at the bottom of the hole, one electronic detonator is charged in each blast hole according to the requirements of the detonation sequence, the detonation package is placed in the upper middle part of the blast hole, after the blast hole is charged, the remaining empty hole section is filled and compacted with clay or drill cuttings, F. After the charging is completed, a concrete partition is constructed above the blast hole and the foundation pit, and after the check is passed, the blasting can be started. Before the construction of the invention patent application, the surface of the blasting area needs to be covered and protected, and a support beam needs to be provided with a protective net, then a bamboo clamping plate is fixed on the protective net, and then a layer of iron mesh is covered and connected into a whole.

[0005] The construction process of the above invention patent application is complex, and the blasting efficiency is low. SUMMARY

[0006] The purpose of the present application is to provide a city sensitive area hard rock shaft shock absorption and noise reduction blasting construction method which can overcome the above technical problems, the method comprising the following steps:

[0007] Step 1, install a bridge type portal crane and a soundproof and noise reduction closed greenhouse on the steel structure column;

[0008] Step 2, drill a blast free face in the middle of the blasting area in the shaft;

[0009] Step 3, use a digging and drilling equipment to drill a slot hole, an auxiliary hole and a peripheral hole;

[0010] Step 4, a row of shock absorption holes is arranged between the peripheral hole and the auxiliary hole;

[0011] Step 5, calculate and install the charge according to the surrounding environmental conditions, topography, stratum rock and shock absorption hole conditions of the construction area;

[0012] Step 6, use a digital electronic detonator in-hole micro-difference segmented detonation method to connect a detonation network;

[0013] Step 7, install the blast cap for noise reduction when blasting;

[0014] Step 8, the blasting section of the urban sensitive area hard rock shaft exceeds 100m 2 Adopt zoning control detonation.

[0015] Further, in step 1, install the bridge type portal crane and soundproof and noise reduction closed greenhouse on the steel structure column, including:

[0016] Step 1.1, set up a soundproof and noise reduction steel structure greenhouse in the shaft construction area, first install the steel structure column, longitudinal reinforcement, and scissors pull rod, adjust the verticality and horizontal elevation of the column, set up the bridge crane track beam on the steel structure column, install the bridge type portal crane on the track beam for vertical transportation and lifting equipment in the shaft;

[0017] Step 1.2, install the top beam and purlin on the steel structure column, install the soundproof backboard on the purlin, the soundproof backboard is made of two thin steel plates sandwiching fire-retardant cotton, the soundproof backboard and the soundproof backboard are connected by a sub-mother tenon buckle connection, the soundproof backboard and the purlin are connected by a bolt connection, the soundproof backboard is fixed on the purlin, and the air exchange and dust removal device is installed on the roof;

[0018] Further, in step 2, drill holes in the middle of the blasting area in the shaft to create a blasting free face, including:

[0019] Step 2.1, during the construction of the fourth system stratum enclosure pile, use the pile forming equipment (rotary drilling + down-the-hole hammer) to drill holes in the middle of the blasting area in the shaft to create a blasting free face, according to the size of the shaft, divide the blasting area into several areas, the drilling diameter is 800mm-1000mm, the drilling depth directly reaches the structure bottom elevation, after hole forming, remove the mud water in the hole, use long polyethylene plastic cylindrical air bag to isolate the clay layer and fill in sections, the section length is consistent with the blasting cycle footage, and the blockage is to the non-blasting position, that is, the mechanical excavation position;

[0020] Step 2.2, remove the isolated clay before each cycle of blasting, remove the long polyethylene plastic cylindrical air bag, form a blasting free face, when using zoning blasting, the area that is detonated first is used as the free face for subsequent detonation.

[0021] Further, in step 3, use the excavated and drilled equipment to drill the slot hole, auxiliary hole, and peripheral hole, including:

[0022] Step 3.1, drill the slot hole, the slot hole diameter is 40mm, the slot hole is arranged along the periphery of the free hole, the hole depth is 2.2m, the minimum resistance line is 0.6m-0.7m, and the hole spacing is 0.6m-0.7m;

[0023] Step 3.2, drill auxiliary eyes, the auxiliary eyes are arranged in a quincunx pattern, the row spacing is 1.1m-1.2m, the hole spacing is 1m-1.1m, and the auxiliary eye hole depth is 2m;

[0024] Step 3.3, drill peripheral eyes, the peripheral eyes are arranged along the peripheral contour line of the foundation pit excavation, the minimum resistance line of the peripheral eyes is 0.7m-0.8m, the hole spacing is 0.4m-0.5m, and the peripheral eye hole depth is 2m.

[0025] Further, in step 4, a row of shock absorption holes is arranged between the peripheral eyes and the auxiliary eyes:

[0026] The shock absorption hole diameter is 80mm-100mm, the spacing is 400mm-500mm, the hole depth is drilled to the structure bottom elevation, the shock absorption hole is segmented backfilled with a long polyethylene plastic cylindrical air bag, the segmented length is consistent with the blasting cycle footage, the long polyethylene plastic cylindrical air bag diameter is 75-95mm, and the peripheral shock absorption hole diameter is consistent with the blast hole diameter, which is 40mm.

[0027] Further, in step 5, the charge is calculated and installed according to the construction area peripheral environmental conditions, topography, stratum rock, and shock absorption hole conditions:

[0028] Step 5.1, according to the construction area peripheral environmental conditions, topography, stratum rock, and shock absorption hole setting conditions, the charge is calculated according to the Sadovnikov single segment detonator maximum charge quantity theoretical formula, and the charge calculation formula is as follows:

[0029] Q = R 3 *(V / K) 3 / a ,

[0030] In the above formula, V is the safety allowed particle vibration velocity, unit: cm / s;

[0031] K is a coefficient related to medium and blasting condition factors;

[0032] Q is the maximum explosive quantity of a single segment detonator, unit: Kg;

[0033] R is the distance from the explosion source to the protected building, unit: m;

[0034] a is the vibration attenuation coefficient;

[0035] Step 5.2, the value range of hard rock and hard rock charge in the above formula: medium-hard rock K value 150-250, a value 1.5-1.8, hard rock K value 50-150, a value 1.3-1.5, the specific value needs to use numerical simulation theory analysis and test to determine. When charging, first fill the 30cm polyethylene water bag into the bottom of the blast hole, fill No. 2 rock emulsion explosive and digital electronic detonator, then fill 50cm water bag, and finally fill the stemming to block, the stemming is processed by stemming machine and composed of clay and machine-made sand waste stone powder, the components are mixed in the proportion of 1:4-5;

[0036] Step 5.3, single-hole single-response is realized by using delay technology, the delay interval is 20ms-65ms, the initiation time interval is 40ms-65ms between holes and 20ms-30ms between rows, the small-diameter cartridge with a diameter of φ24 is used for peripheral holes, and the hole spacing charging method is used;

[0037] Further, in step 6, the in-hole millisecond segmented initiation network of digital electronic detonator is used to connect the initiation network, including:

[0038] Step 6.1, the in-hole millisecond segmented initiation network of digital electronic detonator is used, digital electronic detonators are filled in the hole, and DBⅤⅤ0.5-0.6 blasting main line is used outside the hole, two people are used for networking, the initiation network is connected to the special connection line, i.e. bus bar, through the connection card box, when the connection operation is performed, the farthest end of the blasting face is first started, the head is wrapped with insulating material, and the network is retreated segment by segment and detected, in the network connection, the total resistance value of the whole network deviates from the actual calculated value by not more than ±5%;

[0039] Step 6.2, the maximum number of digital electronic detonators connected to one network branch is not more than 300, each network branch is connected to a cloud initiator, and the cloud initiator is connected to the encoder for initiation through Bluetooth wireless connection.

[0040] Further, in step 7, the blast cap for noise reduction during blasting is installed, including:

[0041] Step 7.1, the blast cap is covered with two layers of rubber woven by waste tires in the foundation pit, the size of the blast cap is 1800mmx2000mm, the sliding rail is installed on the shaft ring beam or the water retaining wall, the blast cap is installed on the sliding rail, the blast cap is processed by welding steel plates, the steel plates are welded into a frame around the steel plates, the steel plates are welded into stiffening ribs in the middle, the bottom surface is fixed on the steel plate by rubber, which is used for noise reduction during blasting, the rubber and the steel plate are fixed by anchor bolts with a spacing of 300mm-400mm, the width of the blast cap is 1.5m, and the length is consistent with the outer edge of the shaft water retaining wall;

[0042] Step 7.2, 2 movable sliding rollers are installed at both ends of the gun cover, and after the gun cover is in place, the gun cover is temporarily fixed on the pre-embedded parts on the concrete shaft ring beam or the water retaining wall to prevent the blasting shock wave from damaging the gun cover.

[0043] Further, in step 8, the blasting section of the hard rock shaft in the urban sensitive area exceeds 100m 2 The partition control initiation is adopted, including:

[0044] The preceding step 1-step 7 is executed according to the preceding step 1-step 7, the rear Ⅱ area takes the Ⅰ area as the free surface, the gradient height is the cycle footage of the Ⅰ area, the initiation sequence is from the first row hole adjacent to the Ⅰ area, and the initiation sequence is from one end to the other end, the initiation time interval is 40ms-65ms between the holes, the time interval between the rows is 20ms-30ms, the row spacing of the caving hole is 1.1m-1.2m, the hole spacing is 1m-1.1m, the hole depth is 2m, the charge of each hole is 0.6kg, the hole spacing of the peripheral hole is 0.5m-0.6m, the hole depth is 2m, the peripheral hole adopts the skip hole charging mode, and the charge of each hole is 0.5kg.

[0045] The blasting construction method has the following superior technical effects:

[0046] 1. The blasting construction method adopts the sound insulation and noise reduction greenhouse and the noise reduction gun cover, so that the influence of the daily life of the residents in the adjacent blasting site residential area is effectively reduced.

[0047] 2. The blasting construction method uses the combination of the rotary drilling and the down-the-hole hammer to form a hole, effectively solves the problem of difficulty in rotary drilling in hard rock, provides a slotting effect for blasting operation, is conducive to realizing single-hole single-resonance of the slotting hole, and can control the blasting vibration speed.

[0048] 3. The blasting construction method first forms a blasting free surface hole on the ground by using a drilling device, and backfills by using an air column, the section length of which is consistent with the blasting cycle footage, so that the stone slag in the blasting operation can be effectively prevented from entering the hollow hole and affecting the free surface effect.

[0049] 4. The section length of the blasting construction method is consistent with the blasting footage, so that the temporary free surface can be quickly removed.

[0050] 5. The blasting construction method drills a row of shock absorption holes between the auxiliary hole and the peripheral hole, which is conducive to enhancing the blasting shock absorption effect.

[0051] 6. The blasting construction method adopts the skip hole interval charging mode in the peripheral hole, which is conducive to reducing the damage of blasting to the surrounding rock, improving the stability of the surrounding rock, and playing a shock absorption role.

[0052] 7、The blasting construction method adopts single-hole single-response hole-in-micro-difference delay blasting technology, and the blasting delay time is in the range of 40ms to 65ms, so that the blasting quality is improved without the problems of subsequent blasting hole shock wave superposition and damage to the subsequent blasting hole foot line after the explosion of the blasting hole.

[0053] 8、The blasting construction method adopts water pressure blasting technology with water bag interval charging mode in the peripheral hole, which is beneficial to improve the blasting effect and reduce the blasting vibration and dust. DETAILED DESCRIPTION

[0054] The embodiments of the present application are described in detail below.

[0055] The blasting construction method comprises the following steps:

[0056] Step 1, installing a bridge-type gantry crane and a soundproof and noise-reducing closed greenhouse on the steel structure column;

[0057] Step 2, drilling a hole in the middle of the blasting area in the vertical shaft to form a blasting free face;

[0058] Step 3, using a digging and drilling device to drill a slot hole, an auxiliary hole and a peripheral hole;

[0059] Step 4, arranging a row of shock absorption holes between the peripheral hole and the auxiliary hole;

[0060] Step 5, calculating and installing the charge according to the surrounding environmental conditions, terrain, stratum rock and shock absorption hole conditions of the construction area;

[0061] Step 6, using a digital electronic detonator hole-in-micro-difference segmented initiation method to connect the initiation network;

[0062] Step 7, installing a blast cap for noise reduction during blasting;

[0063] Step 8, the blasting section of the vertical shaft in the urban sensitive area exceeds 100m 2 The initiation is controlled by zones.

[0064] Further, in step 1, the bridge-type gantry crane and the soundproof and noise-reducing closed greenhouse are installed on the steel structure column, comprising:

[0065] Step 1.1, setting a soundproof and noise-reducing steel structure greenhouse in the vertical shaft construction area, first installing a steel structure column, a longitudinal reinforcement, a scissors drawbar, adjusting the horizontal elevation and verticality of the column, setting a bridge crane running track beam on the steel structure column, and installing a bridge-type gantry crane on the track beam for vertical transportation and lifting equipment in the vertical shaft;

[0066] Step 1.2, install the top beam and purlin on the steel structure column, install the sound insulation backboard on the purlin, the sound insulation backboard is made of two thin steel plates sandwiching fire-retardant cotton, the sound insulation backboard and the sound insulation backboard are connected by a sub-mother tenon buckle connection mode, the sound insulation backboard and the purlin are connected by a bolt connection mode, the sound insulation backboard is fixed on the purlin, and the air exchange and dust removal device is installed on the ceiling;

[0067] Further, in step 2, a blasting free face is drilled in the middle of the blasting area in the shaft, including:

[0068] Step 2.1, during the construction of the fourth stratum enclosure bored pile, a blasting free face is drilled in the middle of the blasting area in the shaft by using the pile-forming equipment (rotary drilling + down-the-hole hammer), according to the size of the shaft, the blasting area is divided into several areas, the drilling diameter is 800mm-1000mm, the drilling depth directly reaches the structure bottom elevation, after the hole is formed, the mud water in the hole is removed, the long polyethylene plastic cylindrical air bag is isolated, the length of the section is consistent with the blasting cycle footage, and the non-blasting position is blocked, that is, the mechanical excavation position is used.

[0069] Step 2.2, before each cycle of blasting, the isolated clay is removed, the long polyethylene plastic cylindrical air bag is removed, and the blasting free face is formed, when using zoned blasting, the area that is initiated first is used as the free face for subsequent initiation.

[0070] Further, in step 3, a drilling and slotting device is used to drill slot holes, auxiliary holes and peripheral holes, including:

[0071] Step 3.1, drill slot holes, the slot hole diameter is 40mm, the slot holes are arranged along the periphery of the free hole, the hole depth is 2.2m, the minimum resistance line is 0.6m-0.7m, and the hole spacing is 0.6m-0.7m;

[0072] Step 3.2, drill auxiliary holes, the auxiliary holes are arranged in a quincunx pattern, the row spacing is 1.1m-1.2m, the hole spacing is 1m-1.1m, and the auxiliary hole depth is 2m;

[0073] Step 3.3, drill peripheral holes, the peripheral holes are arranged along the periphery of the foundation pit excavation contour line, the minimum resistance line of the peripheral holes is 0.7m-0.8m, the hole spacing is 0.4m-0.5m, and the peripheral hole depth is 2m.

[0074] Further, in step 4, a row of shock absorption holes is arranged between the peripheral holes and the auxiliary holes:

[0075] The shock absorption hole diameter is 80mm-100mm, the interval is 400mm-500mm, the hole depth is drilled to the structure bottom elevation, the shock absorption hole is backfilled by long polyethylene plastic cylindrical air bag in sections, the section length is consistent with the blasting cycle footage, the long polyethylene plastic cylindrical air bag diameter is 75-95mm, and the peripheral shock absorption hole diameter is consistent with the blast hole diameter of 40mm.

[0076] Further, in step 5, the charge is calculated and installed according to the construction area surrounding environment conditions, terrain, stratum rock and shock absorption hole conditions:

[0077] Step 5.1, according to the construction area surrounding environment conditions, terrain, stratum rock and shock absorption hole setting conditions, the charge is calculated according to the Sadovskiy single segment detonator maximum charge quantity theoretical formula, and the charge calculation formula is as follows:

[0078] Q = R 3 *(V / K) 3 / a ,

[0079] In the above formula: V is the safety allowed particle vibration velocity, unit: cm / s;

[0080] K is a coefficient related to medium and blasting condition factors;

[0081] Q is the maximum explosive quantity of single segment detonator, unit: Kg;

[0082] R is the distance from the explosion source to the protected building, unit: m;

[0083] a is the vibration attenuation coefficient;

[0084] Step 5.2, the value range of hard rock and hard rock charge in the above formula: medium hard rock K value is 150-250, a value is 1.5-1.8, hard rock K value is 50-150, a value is 1.3-1.5, the specific value needs to be determined by numerical simulation theoretical analysis and test test. When charging, 30cm polyethylene water bag is filled into the bottom of the blast hole, No. 2 rock emulsion explosive and digital electronic detonator are filled, 50cm water bag is filled, and finally the stemming is blocked, the stemming is processed by stemming machine and composed of clay and machine-made sand waste stone powder, the components are mixed in the proportion of 1:4-5;

[0085] Step 5.3, single hole single response is realized by using delay technology, the delay interval is 20ms-65ms, the initiation time interval is 40ms-65ms between holes and holes, the time interval between rows is 20ms-30ms, the peripheral hole adopts small diameter cartridge with diameter φ24, and adopts hole separation charging method; as shown in Table 1;

[0086] Further, in step 6, the digital electronic detonator hole micro-difference segmented initiation method is used to connect the initiation network, including:

[0087] Step 6.1, adopt digital electronic detonator hole in-hole differential segmented initiation network, hole in-hole digital electronic detonator, hole outside adopts DB Ⅴ Ⅴ 0.5-0.6 blasting main line connection, networking adopts double person production, initiation network is connected through a connection card box and is connected to a special connection line, namely a bus, when connecting, first start from the farthest end of the blasting face, the head is wrapped with insulating material, retreats to the initiation station segment by segment, and the network conduction detection is carried out segment by segment, in the network connection, the total resistance value of the whole network deviates from the actual calculation value by not more than ±5%;

[0088] Step 6.2, a parallel connection network branch line does not exceed 300 digital electronic detonators, each network branch line is connected to a cloud detonator, and the cloud detonator is initiated through a Bluetooth wireless connection encoder.

[0089] Further, in step 7, a blast cover for reducing noise during blasting is installed, including:

[0090] Step 7.1, the blast cover is covered with two layers of waste tire rubber woven in the foundation pit, the blast cover size is 1800mmx2000mm, the sliding track is installed on the shaft ring beam or the water retaining wall, the blast cover is installed on the sliding track, the blast cover is welded and processed from steel plates, the steel plates are welded into a frame around the steel plates, the middle part is welded into a stiffening rib transversely by the I-beam, the bottom surface is fixed on the steel plate by rubber, which is used for reducing noise during blasting, the rubber and the steel plate are fixed by anchor nails with a spacing of 300mm-400mm, the width of the blast cover is 1.5m, and the length is consistent with the outer edge of the shaft water retaining wall;

[0091] Step 7.2, two movable sliding rollers are installed at both ends of the blast cover, after the blast cover is in place, the blast cover is temporarily fixed on the embedded parts on the concrete shaft ring beam or the water retaining wall to prevent the blast cover from being damaged by the blast shock wave.

[0092] Further, in step 8, the blasting section of the hard rock shaft in the urban sensitive area exceeds 100m 2 Adopting zoned control initiation, including:

[0093] The first row of holes in the first zone is initiated according to the foregoing steps 1-7, the second zone is taken as the free surface of the first zone, the gradient height is the circulating footage of the first zone, the initiation sequence is from the first hole near the first zone to the other end in turn, the initiation time interval is 40ms-65ms between holes and 20ms-30ms between rows, the row spacing of the caving holes is 1.1m-1.2m, the hole spacing is 1m-1.1m, the hole depth is 2m, the charge per hole is 0.6kg; the hole spacing of the peripheral holes is 0.5m-0.6m, the hole depth is 2m, the peripheral holes adopt skip hole charging, and the charge per hole is 0.5kg, as shown in Table 2.

[0094] Table 1

[0095]

[0096] Table 2

[0097]

[0098] The above description is merely that of a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the scope of the present application, which should be covered in the protection scope of the claims of the present application.

Claims

1. A vibration and noise reduction blasting construction method for hard rock shaft in urban sensitive area, characterized in that, Includes the following steps: Step 1: Install a bridge-type gantry crane and a soundproof and noise-reducing enclosed greenhouse on the steel structure columns: Step 1.1: Set up a soundproof and noise-reducing steel structure shed in the vertical shaft construction area. First, install steel structure columns, longitudinal tie rods, and scissor tie rods. Adjust the horizontal elevation and verticality of the columns. Set up a bridge crane traveling track beam on the steel structure columns. Install a bridge-type gantry crane on the track beam for vertical transportation and lifting equipment in the vertical shaft. Step 1.2: Install the top beam and purlins on the steel structure columns, and install the sound insulation back panel on the purlins. The sound insulation back panel is made of two thin steel plates sandwiching flame-retardant cotton. The sound insulation back panels are connected to each other by a mortise and tenon joint. The sound insulation back panel is bolted to the purlins. Fix the sound insulation back panel to the purlins. Install the ventilation and dust removal device on the ceiling. Step 2: Drill holes in the center of the blasting area inside the shaft to create a blasting free face; Step 3: Use excavator-to-drill equipment to drill the slotting holes, auxiliary holes, and peripheral holes; Step 4: Set a row of shock-absorbing holes between the peripheral holes and the auxiliary holes; the diameter of the shock-absorbing holes is 80mm~100mm, the spacing is 400mm~500mm, and the hole depth is drilled to the bottom elevation of the structure. The shock-absorbing holes are backfilled in sections using long polyethylene plastic cylindrical air bags. The section length is consistent with the blasting cycle advance. The diameter of the long polyethylene plastic cylindrical air bags is 75~95mm, and the diameter of the peripheral shock-absorbing holes is consistent with the diameter of the blast holes, which is 40mm. Step 5: Calculate and install the explosive charge based on the surrounding environmental conditions, topography, strata, rock formations, and vibration damping hole conditions of the construction area; Step 6: Connect the detonation network using the digital electronic detonator's in-hole micro-differential segmented detonation method; Step 7: Install the blasting cover for noise reduction during blasting: Step 7.1: Cover the pit with two layers of blasting cover woven from waste tire rubber. The blasting cover is 1800mm x 2000mm in size. Install sliding rails on the shaft ring beam or retaining wall, and install blasting covers on the sliding rails. The blasting covers are made of welded steel plates. The steel plates are framed by welded I-beams around the perimeter, and stiffening ribs are welded horizontally by I-beams in the middle. The bottom surface is fixed to the steel plate with rubber for noise reduction during blasting. The rubber is fixed to the steel plate with anchors at a spacing of 300mm to 400mm. The width of the blasting cover is 1.5m, and the length is consistent with the outer edge of the shaft retaining wall. Step 7.2: Install two movable sliding rollers at each end of the blasting cover. After the blasting cover is in place, temporarily fix it to the embedded parts on the concrete shaft ring beam or the water retaining wall to prevent the blasting shock wave from damaging the blasting cover. Step 8, the blasting section of hard rock shaft in urban sensitive area exceeds 100m 2 The partition control initiation is adopted.

2. The vibration-damping and noise-reducing blasting construction method for hard rock shaft in urban sensitive areas according to claim 1, characterized in that, Step 2 includes the following steps: Step 2.1: During the completion of the bored pile construction of the Quaternary stratum retaining structure, a blasting free face is created by drilling a hole in the middle of the blasting area in the vertical shaft using the bored pile forming equipment. The blasting area is divided into several areas according to the size of the vertical shaft. The borehole diameter is 800mm~1000mm, and the borehole depth directly reaches the bottom elevation of the structure. After the hole is formed, the mud and water in the hole are removed. Long polyethylene plastic cylindrical air bags are used to isolate the clay layer and fill it in sections. The section length is consistent with the blasting cycle advance. The blockage extends to the non-blasting area, that is, the location where mechanical excavation is carried out. Step 2.2: Before each blasting cycle, remove the isolation clay and take out the long polyethylene cylindrical air bag to form the blasting free face. When using zoned blasting, the area that is detonated first serves as the free face for subsequent detonations.

3. The method according to claim 1, wherein the method is characterized in that, Step 3 includes the following steps: Step 3.1: Drill slots with a diameter of 40mm. The slots are arranged around the perimeter of the open hole, with a depth of 2.2m, a minimum resistance line of 0.6m~0.7m, and a hole spacing of 0.6m~0.7m. Step 3.2: Drill auxiliary holes. The auxiliary holes are arranged in a quincunx pattern with a row spacing of 1.1m to 1.2m and a hole spacing of 1m to 1.1m. The depth of the auxiliary hole is 2m. Step 3.3: Drill peripheral holes. The peripheral holes are arranged around the perimeter of the excavation outline of the foundation pit. The minimum resistance line of the peripheral holes is 0.7m~0.8m, the hole spacing is 0.4m~0.5m, and the depth of the peripheral hole is 2m.

4. The method for vibration reduction and noise reduction blasting construction of hard rock shafts in urban sensitive areas according to claim 1, characterized in that, Step 5 includes the following steps: Step 5.1: Based on the surrounding environmental conditions, topography, strata, and vibration damping hole layout of the construction area, calculate the charge according to the Sadovsky single-section detonator maximum charge theoretical formula. The charge calculation formula is as follows: Q = R 3 *(V / K) 3 / а , In the above formula: V is the safe and permissible particle vibration velocity, in cm / s; K is a coefficient related to the medium and blasting conditions; Q represents the maximum explosive charge in a single detonator, expressed in kg. R is the distance from the blast source to the protected building, in meters; a is the vibration attenuation coefficient; Step 5.2: The range of values ​​for the charge amount in the above formula for hard rock and hard rock is as follows: for medium-hard rock, K is 150~250 and a is 1.5~1.8; for hard rock, K is 50~150 and a is 1.3~1.

5. The specific values ​​need to be determined by numerical simulation theory analysis and experimental testing. When charging, first put a 30cm polyethylene water bag into the bottom of the borehole, then put in No. 2 rock emulsion explosive and digital electronic detonator, then put in a 50cm water bag, and finally put in the gunning mud to seal it. The gunning mud is processed by the gunning mud machine and is composed of clay and manufactured sand waste stone powder. The components are mixed in a ratio of 1:4~5. Step 5.3: Use delay technology to achieve single-hole single-fire, with a delay interval of 20ms~65ms, an initiation interval of 40ms~65ms between holes, and an interval of 20ms~30ms between rows. Use small-diameter explosive cartridges with a diameter of φ24 for the peripheral holes and adopt a spaced-hole loading method.

5. The method for vibration reduction and noise reduction blasting construction of hard rock shafts in urban sensitive areas according to claim 1, characterized in that, Step 6 includes the following steps: Step 6.1: A digital electronic detonator-based micro-differential segmented initiation network is adopted. The digital electronic detonator is installed inside the hole, and the DB VV 0.5-0.6 blasting main line is used for connection outside the hole. The network is operated by two people. The initiation network is connected to the dedicated connection line (busbar) through the junction box. When connecting the network, start from the farthest end of the blasting working face. The end cap is wrapped with insulating material. Move backward segment by segment towards the initiation station and perform network continuity test segment by segment. During the network connection, the deviation between the total resistance value of the entire network and the actual calculated value shall not exceed ±5%. Step 6.2: Connect a network branch line to a maximum of 300 digital electronic detonators. Connect each network branch line to a cloud detonator. The cloud detonator is wirelessly connected to the encoder via Bluetooth to initiate the detonation.

6. The method for vibration reduction and noise reduction blasting construction of hard rock shafts in urban sensitive areas according to claim 1, characterized in that, Step 8 includes: the blasting method for Zone I is performed according to steps 1 to 7 above; the blasting for Zone II is carried out with Zone I as the free face, the step height is the cyclic advance of Zone I, and the detonation sequence starts from the first row of holes adjacent to Zone I, and detonates sequentially from one end to the other. The detonation time interval is 40ms to 65ms between holes, and 20ms to 30ms between rows. The spacing between rows of collapse holes is 1.1m to 1.2m, the spacing between holes is 1m to 1.1m, the hole depth is 2m, and the charge per hole is 0.6kg; the spacing between peripheral holes is 0.5m to 0.6m, the hole depth is 2m, and the peripheral holes adopt a skip-hole charging method with a charge of 0.5kg per hole.

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