A reinforced concrete prop and a method of blasting demolition thereof for a structure

Abstract

The present application relates to a reinforced concrete pillar and a method for blasting demolition of a structure, which forms a door hole by breaking a supporting cylinder wall of a high-rise structure, replaces the supporting system of the door hole with an axial pre-buried hole reinforced concrete pillar, and simultaneously charges and blasts in the pre-buried hole while drilling and charging in the remaining supporting cylinder wall, thereby achieving the blasting demolition of the high-rise structure. The present application can greatly improve the safety of blasting demolition, ensure the accuracy of directional collapse, greatly reduce the consumption of explosives and detonators, simplify the blasting network and charging operation, greatly reduce the blasting vibration and blasting dust, and achieve a more green blasting demolition. The present application is suitable for the blasting demolition of high-rise structures such as chimneys, water towers and silos made of bricks, concrete and reinforced concrete, and has a wide range of applications.

Description

Technical Field

[0001] This invention relates to the field of demolition by explosives, specifically to a reinforced concrete pillar and a method for demolishing it by explosives. Background Technology

[0002] For the demolition of tall structures, manual and mechanical demolition are gradually being phased out due to their low efficiency and safety. Existing cases of tall structure replacement demolition involve replacing the supporting cylinder wall of the blasting cut with wooden piles, and then using gasoline to burn the wooden piles to disable them, thus achieving the purpose of demolishing the tall structure. However, this method still has the characteristics of small and numerous wooden pile replacement areas, long burning time, difficulty in controlling the collapse direction, and low safety. At present, mechanical demolition of tall structures mainly uses long-arm demolition machines. Mechanical demolition has the advantages of eliminating the safety approval of blasting demolition, short construction period, and low cost. However, it still has the disadvantages of difficulty in controlling the collapse direction and flying rocks, which endangers the safety of construction workers.

[0003] Drilling and blasting is widely used in the demolition of tall structures due to its safety and efficiency. However, because tall structures have a large height-to-diameter ratio, relatively small support area, and relatively thin support walls, drilling and blasting requires a large number of boreholes, resulting in high labor costs. At the same time, the thin support walls lead to low energy utilization of explosives and high explosive consumption. The number of detonators and plugging materials required for the blast holes is also high, and the blasting causes a rapid increase in dust, affecting the surrounding environment. In addition, the traditional directional window combined with drilling and blasting demolition method has a complex blasting network due to the large number of blast holes, which increases the risk of blasting network failure and misfire, thus leading to demolition failure. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a reinforced concrete support column and its method for demolishing structures by blasting. The main method involves replacing the support cylinder wall located at the blasting cut with an axially pre-embedded hole reinforced concrete support column system. This transforms the blasting of a large area support cylinder wall into the axial charging blasting of several axially pre-embedded hole reinforced concrete supports, thereby reducing the consumption of explosives and detonators, significantly optimizing the blasting network, and mitigating the impact of blasting on the surrounding environment.

[0005] The present invention discloses a reinforced concrete support column, which includes a column head, a pre-embedded hole, and a column body. The reinforced concrete support column is prefabricated and has a rectangular or circular cross-section. The column head of the reinforced concrete support column expands outward. The pre-embedded hole is located in the middle of the reinforced concrete support column and is axially pre-embedded. The upper bend of the pre-embedded hole bends up at the point where the cross-section of the reinforced concrete support column begins to expand. The pre-embedded hole opens on the side surface of the column head of the reinforced concrete support column.

[0006] As a further improvement of the present invention, the cross-sectional dimensions of the reinforced concrete column are 300-1000mm, the height h of the column head expansion is 200-400mm, the width c of the column head expansion is 200-400mm, and the diameter of the pre-embedded hole is 40-100mm.

[0007] A reinforced concrete support system with axially embedded holes, characterized in that it includes a reinforced concrete support column, as well as a steel plate, a jack, a protective cover, and a pad.

[0008] As a further improvement of the present invention, the protective cover has a notch on its side, the vertical bearing surface of the protective cover is larger than the cross-sectional dimension of the column, and the internal height of the protective cover is not less than the minimum height of the jack.

[0009] A method for demolishing tall structures by breaking through walls and replacing columns with reinforced concrete pillars, characterized by the following steps:

[0010] Step 1: Set a blasting incision below the support cylinder wall, and divide the support cylinder wall within the blasting incision range into several replacement sections and retention sections;

[0011] Step 2: Make blast holes in the retained area, then break up the replacement area to form a doorway, and place an axially pre-embedded reinforced concrete support system in the doorway.

[0012] Step 3: Fill the pre-embedded holes and blast holes with explosives and seal them with blasting mud, while simultaneously leading out the detonator lead wire;

[0013] Step 4: Connect all detonator leads to form an initiation network, provide close-range protection for the reinforced concrete pillars and the reserved area, and finally activate the initiation network.

[0014] As a further improvement to this method, in step one, the width of a single replacement area is 1.2 to 3.0 m, the width of a single retention area is 1.0 to 3.0 m, and the replacement areas and retention areas are arranged alternately.

[0015] As a further improvement to this method, the substitution method in step two includes the following steps:

[0016] S1, starting from the first replacement zone immediately adjacent to the collapse centerline;

[0017] S2. The cylinder wall located in the first replacement zone is broken, forming a doorway;

[0018] S3. On the flat ground below the replacement area, place the pad, jack, and protective cover in sequence from bottom to top at the accurate position supported by the reinforced concrete column.

[0019] S4. Move the precast reinforced concrete support onto the protective cover;

[0020] S5. Place the steel plate on the reinforced concrete support;

[0021] S6. Raise the jacks until the reinforced concrete pillars reach the load-bearing requirements, then stop raising the jacks to complete the replacement of the first replacement area.

[0022] S7. Use the same method to complete the construction of the remaining replacement areas, and proceed symmetrically towards both sides of the collapse centerline.

[0023] As a further improvement to this method, in step two, the drilling direction of the reserved area is selected to be either parallel to the support cylinder wall of the reserved area (i.e., perpendicular to the door opening cutting surface) or perpendicular to the support cylinder wall of the reserved area.

[0024] As a further improvement to this method, the construction sequence of all replacement areas is to start replacement from the first replacement area immediately adjacent to the collapse centerline, and then replace several replacement areas at intervals until all replacement areas are replaced.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1. This invention replaces the blasting of large-area thin-walled support cylinders with the blasting of reinforced concrete pillars with several axially pre-embedded holes, improving the energy utilization rate of explosives, reducing the consumption of explosives and detonators, and making the blasting demolition work safer. The axially pre-embedded hole reinforced concrete pillars can be manufactured into building products according to the building scale, which helps improve construction efficiency and ensures the quality of the axially pre-embedded hole reinforced concrete pillars. Furthermore, the significant reduction in the number of blast holes greatly simplifies the blasting network, improves the reliability of network initiation, ensures the accuracy of directional collapse of tall structures, and ensures the safety of construction personnel and surrounding buildings.

[0027] 2. In this invention, the drilling of the reserved area can be selected parallel to the direction of the reserved area support cylinder wall. Compared with the direction perpendicular to the direction of the reserved area support cylinder wall, the depth of the blast hole is increased, which improves the energy utilization rate of the explosive and prevents the blast hole from being punched.

[0028] 3. This invention significantly reduces the amount of explosives used, resulting in a substantial decrease in the total amount of explosives used in a single blast, thus lowering the level of blasting operations. At the same time, blasting vibration, blasting dust, and the distance of flying debris are all significantly reduced, effectively controlling the harmful effects of blasting and greatly minimizing the impact of blasting on the surrounding environment, making blasting demolition more green and environmentally friendly. Attached Figure Description

[0029] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0030] Figure 1 This is a schematic diagram of a partial cylinder wall replacement in one example of the present invention;

[0031] Figure 2 This is a diagram of the blasting cut section in one example of the present invention;

[0032] Figure 3 This is a diagram showing the unfolded blasting cut after replacement in one example of this invention;

[0033] Figure 4 This is a diagram showing the unfolded shape of a single permutation region in one example of this invention;

[0034] Figure 5 for Figure 4 In the cross-sectional view of AA;

[0035] Figure 6 for Figure 4 In the cross-sectional view of BB;

[0036] Figure 7 for Figure 4 Cross-sectional view of CC;

[0037] Figure 8 This is a schematic diagram of an axially pre-embedded hole reinforced concrete column support system in one example of the present invention.

[0038] Figure 9 This is a schematic diagram of a protective cover in one example of the present invention;

[0039] Figure 10 This is a cross-sectional view of the reinforcement of a reinforced concrete column in one example of the present invention;

[0040] Figure 11 This is a schematic diagram of the partial cylinder wall replacement in another case of no-retainment area in this invention;

[0041] Figure 12 This is a schematic diagram of the wall replacement in another example of a square cylindrical wall in this invention;

[0042] Figure 13 This is a diagram of a pre-embedded hole for loading explosives in one example of this invention;

[0043] Figure 14 This is a diagram of a blast hole charging method in one example of the present invention;

[0044] Figure 15 This is a schematic diagram of the detonation network in one example of the present invention.

[0045] In the diagram: 1. Supporting cylinder wall; 101. Replacement area; 102. Retained area; 2. Doorway; 3. Collapse centerline; 4. Ground; 5. Steel plate; 6. Reinforced concrete support column; 601. Column head; 602. Embedded hole; 603. Column body; 7. Protective cover; 8. Jack; 9. Pad plate; 10. Blasting hole; 11. Explosive; 12. Electronic detonator; 13. Blasting clay; 14. Detonator lead wire; 15. Wire; 16. Detonation power supply. Detailed Implementation

[0046] The following illustrations disclose several embodiments of the present invention. For clarity, many physical details will be described in the following description. However, it should be understood that these physical details are not intended to limit the invention. That is, in some embodiments of the invention, these physical details are not essential. Furthermore, for the sake of simplicity, some conventional structures and components will be shown in the illustrations in a simple schematic manner.

[0047] Please see Figure 1 , Figure 1 This is a schematic diagram of the lower part of a circular tall structure after the wall of the cylindrical section has been broken and replaced with columns. It includes the supporting cylindrical wall 1, the preserved area 102, the doorway 2, the collapse centerline 3, the ground 4, the steel plate 5, and the axially embedded hole reinforced concrete column support system. The axially embedded hole reinforced concrete column support system includes reinforced concrete columns 6, protective covers 7, jacks 8, and pads 9. The supporting cylindrical wall 1 at the blasting cut is first cut and broken, and then replaced with the axially embedded hole reinforced concrete column support system at the cut. This can greatly reduce the amount of blasting and drilling work. At the same time, for safety reasons, the preserved area 102 is set up for drilling and blasting. The size of the preserved area 102 is comprehensively considered based on the structural characteristics of the tall structure.

[0048] Preferably, the breaking of the cylinder wall in the replacement section 101 should ensure that the upper edge of the cut is flat and subjected to force, and the breaking tool is preferably a wall saw or a wire saw.

[0049] Please see Figure 2 , Figure 2 It is a blasting cut zoning diagram, including the supporting cylinder wall 1, replacement zone 101, retention zone 102, and collapse center line 3; the width of the replacement cut and the retention zone 102 are determined by the height and width of the blasting cut, combined with the structural characteristics and bottom thickness of the tall structure.

[0050] Please see Figure 3 This is an unfolded diagram after the replacement of the blasting cut, including the preserved area 102, the doorway 2, the collapse centerline 3, the steel plate 5, the reinforced concrete support 6, the protective cover 7, the jack 8, the pad 9, and the blast hole 10, which shows the specific replacement position relationship of the blasting cut.

[0051] Please see Figure 4This is an unfolded diagram of a single replacement area 101, including the supporting cylinder wall 1, the ground of the retained area 102 4, the steel plate 5, the reinforced concrete column 6, the column head 601, the pre-embedded hole 602, the column body 603, the protective cover 7, the jack 8, the pad plate 9, and the blast hole 10; it shows the relative positional relationship between the reinforced concrete column 6 and the retained area 102.

[0052] Qing Reference Figure 5 ,yes Figure 4 The sectional view of section AA includes the supporting cylinder wall 1, the reserved area 102, the steel plate 5, the reinforced concrete column 6, the column head 601, the pre-embedded hole 602, and the blast hole 10. The width of the steel plate 5 is equal to the wall thickness of the supporting cylinder wall 1, the width of the reinforced concrete column 6 is slightly less than the wall thickness of the supporting cylinder wall 1, the cross-section of the reinforced concrete column 6 is square or circular, the width of the outward expansion of the column head 601 is generally 200-400mm, the depth of the blast hole 10 is 2 / 3 to 3 / 4 of the width of the reserved area 102, and the direction of the blast hole 10 is parallel to the direction of the supporting cylinder wall 1 or perpendicular to the direction of the supporting cylinder wall 1.

[0053] Please see Figure 6 ,yes Figure 4 The sectional view of section BB includes the supporting cylinder wall 1, the ground 4, and the blast holes 10. When the wall thickness of the supporting cylinder wall 1 is less than 40cm, one row of blast holes 10 can be arranged. When the wall thickness of the supporting cylinder wall 1 is greater than 60cm, multiple rows of blast holes 10 can be arranged. The spacing between the blast holes 10 is 30-50cm, and the diameter of the blast holes 10 is 30-50mm.

[0054] Please see Figure 7 ,yes Figure 4 The sectional view of section CC includes the reserved area 102, ground 4, reinforced concrete column 6, column head 601, embedded hole 602, column body 603, protective cover 7, and blast hole 10; the cross-sectional dimension of the reinforced concrete column 6 and column body 603 is slightly smaller than the vertical cross-sectional dimension of the protective cover 7, and the embedded hole 602 is located in the middle of the cross-section of the reinforced concrete column 6.

[0055] Please see Figure 8 This is a schematic diagram of a reinforced concrete support column 6, which includes a steel plate 5, a reinforced concrete support column 6, a protective cover 7, a jack 8, and a pad 9, demonstrating the specific form of the axially pre-embedded hole reinforced concrete support column system.

[0056] The pre-embedded hole 602 is made of PVC pipe with a diameter of 40mm. The upper elbow of the pre-embedded hole 602 bends up at the point where the cross-section of the reinforced concrete column 6 begins to expand and opens on the side surface of the column head 601 of the reinforced concrete column 6 with a bend radius of 400mm. The bottom through hole of the pre-embedded hole 602 extends to 30cm from the bottom surface of the reinforced concrete column 6.

[0057] The reinforced concrete column 6 has a rectangular cross-section with dimensions of 400×400mm. The column head 601 of the reinforced concrete column 6 expands outward, with an outward expansion height of 200mm and an outward expansion width of 200mm. The reinforcement of the column must meet the requirements of the specifications.

[0058] Please see Figure 9 This is a schematic diagram of a protective cover 7 in one example of the present invention. The protective cover 7 is made of metal; the thickness of the protective cover 7 is 3cm; the protective cover 7 is a box shape with an open top and unequal lengths on both sides; the vertical bearing surface dimension of the protective cover 7 is slightly larger than the cross-sectional dimension of the reinforced concrete column 6; the internal height of the protective cover 7 is slightly larger than the initial height of the jack 8.

[0059] Please see Figure 10 This is a cross-sectional view of the reinforcement of a reinforced concrete column 6 in one example of the present invention, including the reinforced concrete column 6, column head 601, pre-embedded hole 602, and column body 603; it shows the form of the height h and the width c of the outer extension of the column head 601, and the reinforcement of the reinforced concrete column 6 must meet the specifications.

[0060] Please see Figure 11 This is a schematic diagram of the lower part of the cylindrical wall of the circular tall structure 102 after the wall was broken and the columns were replaced. It includes the supporting cylindrical wall 1, doorway 2, collapse center line 3, ground 4, steel plate 5, reinforced concrete column 6, protective cover 7, jack 8, and pad 9.

[0061] Please see Figure 12 This is a schematic diagram of the lower part of the square, tall structure after the wall was broken and the columns were replaced, including the supporting cylindrical wall 1, the preserved area 102, the doorway 2, the collapse center line 3, the ground 4, the steel plate 5, the reinforced concrete column 6, the protective cover 7, the jack 8, the pad 9, and the blast hole 10.

[0062] Please see Figure 13 This is a schematic diagram of the loading of explosives in the pre-embedded hole 602 in one example of the present invention, including a reinforced concrete support 6, explosives 11, electronic detonator 12, stemming clay 13, and detonator lead wire 14; continuous loading is adopted, stemming clay 13 is used to block the explosives, and electronic detonator 12 is used to detonate.

[0063] Please see Figure 14 This is a schematic diagram of the charge loading of a borehole 10 in one example of the present invention, including a retaining area 102, explosive 11, electronic detonator 12, stemming material 13, and detonator lead wire 14; continuous charge is used, stemming material 13 is used to block the charge, and electronic detonator 12 is used to detonate.

[0064] Please see Figure 15This is a schematic diagram of an initiation network in one example of the present invention, including an electronic detonator 12, a wire 15, and an initiation power supply 16; an MS3 detonator is used inside the hole, and an MS1 ​​detonator is used to bind the hole outside, which is connected to the initiation power supply 16.

[0065] The purpose of this invention is to provide a method for demolishing tall structures by breaking through walls and replacing columns using axially pre-embedded reinforced concrete columns 6. The method involves calculating the height and width of the blasting cut required for the collapse of the tall structure, dividing the blasting cut of the supporting cylinder wall 1 of the tall structure into several replacement zones 101 and retention zones 102. Starting from the first replacement zone 101 adjacent to the collapse centerline 3, the cylinder wall of the first replacement zone 101 is broken to form a doorway 2. Holes are drilled in the retention zone 102, and the support system is replaced with an axially pre-embedded reinforced concrete column support system at the doorway 2, until all replacement zones 101 are replaced. Then, explosives are loaded, plugged, meshed, protected, and blasted in the pre-embedded holes 602 of the reinforced concrete column 6 and the blast holes 10 of the retention zone 102.

[0066] The axially pre-embedded hole reinforced concrete column support system can be manufactured into products according to certain specifications based on statistical data of tall structures, which can improve construction efficiency and at the same time ensure the quality of the axially pre-embedded hole reinforced concrete column support system.

[0067] The width of a single replacement zone 101 is 1.2 to 3.0 m, and the width of a single retention zone 102 is 1.0 to 3.0 m. Replacement zones 101 and retention zones 102 are arranged at intervals, and the replacement zones 101 and retention zones 102 are symmetrically distributed on both sides of the collapse centerline 3.

[0068] The reinforced concrete column 6 is made of high-strength concrete, with a strength grade at least two levels higher than that of the original material of the tall structure.

[0069] This invention also provides a method for demolishing tall structures by breaking through walls and replacing columns using an axially pre-embedded hole reinforced concrete column support system, comprising the following steps:

[0070] Step 1: Set a blasting cut below the support cylinder wall 1, and divide the support cylinder wall 1 within the blasting cut range into several replacement areas 101 and retention areas 102;

[0071] Step 2: Open blast holes 10 on the retained area 102, then break up the replacement area 101 to form a doorway 2, and place an axially pre-embedded hole reinforced concrete support system in the doorway 2.

[0072] Step 3: Fill the pre-embedded hole 602 and the blast hole 10 with explosives 11 and plug them with blasting mud 13, and at the same time lead out the detonator lead wire 14;

[0073] Step 4: Connect all detonator leads 14 to form an initiation network, provide close-range protection for the reinforced concrete support column 6 and the reserved area 102, and finally activate the initiation network.

[0074] As a further improvement to the above method, in step one, the width of a single replacement area 101 is 1.2 to 3.0 m, the width of a single retention area 102 is 1.0 to 3.0 m, and the replacement area 101 and the retention area 102 are arranged at intervals.

[0075] As a further improvement to the above method, the substitution method in step two includes the following steps:

[0076] S1, starting from the first replacement zone 101 immediately adjacent to the collapse centerline 3;

[0077] S2. The cylinder wall located in the first replacement zone 101 is broken, forming the doorway 2;

[0078] S3. On the flat ground 4 below the replacement area 101, place the pad 9, jack 8, and protective cover 7 in sequence from bottom to top on the accurate position supported by the reinforced concrete column 6.

[0079] S4. Move the precast reinforced concrete support column 6 onto the protective cover 7;

[0080] S5. Place the steel plate 5 on the reinforced concrete support 6;

[0081] S6. Lift jack 8. Once the reinforced concrete support 6 reaches the bearing capacity, stop lifting and complete the replacement of the first replacement area 101.

[0082] S7. Use the same method to complete the construction of the remaining replacement area 101. The construction sequence is symmetrical and proceeds towards both sides of the collapse center line 3.

[0083] As a further improvement to the above method, in step two, the drilling direction of the retained area 102 is selected to be parallel to the support cylinder wall 1 of the retained area 102 or perpendicular to the support cylinder wall 1 of the retained area 102.

[0084] As a further improvement to the above method, the construction sequence of all replacement areas 101 is to start replacement from the first replacement area 101 immediately adjacent to the collapse centerline 3, and then replace it at intervals of several replacement areas 101 until all replacement areas 101 are replaced.

[0085] Specifically, the construction methods for demolishing tall structures by breaking through walls and replacing columns using explosives are as follows:

[0086] Based on the surrounding environment and the structural characteristics of the tall structure, determine the direction of collapse of the tall structure; calculate the height and width of the blasting cut required for the collapse of the tall structure using empirical formulas;

[0087] The supporting cylinder wall 1 within the blasting cut range is divided into several replacement areas 101 and retention areas 102. After precise measurement, the specific locations of the replacement areas 101 and retention areas 102 are marked with paint.

[0088] The axially embedded hole reinforced concrete column support system is prefabricated in advance according to the size and quantity of replacement area 101;

[0089] The non-structural lining inside the tall structure was pre-removed; at the same time, shock-absorbing trenches were set up in the direction of collapse.

[0090] The cylinder wall of the first replacement section 101 adjacent to the collapse center line 3 is broken with a crushing tool to form a doorway 2. Then, holes are drilled in the retained section 102, and the ground 4 and the upper edge of the cut are leveled to ensure good force transmission.

[0091] Place the two unlifted jacks 8 on the pad plate 9 and put them in the protective cover 7, and place them in the accurate position of the reinforced concrete column 6 supporting the load-bearing system.

[0092] The precast reinforced concrete support column 6 is moved onto the protective cover 7 using machinery;

[0093] Place the steel plate 5 on the two reinforced concrete pillars 6;

[0094] Next, lift jack 8 until the axial pre-embedded hole reinforced concrete support system reaches the bearing requirements, then stop lifting to complete the replacement of the first replacement area 101.

[0095] The replacement of the remaining replacement areas 101 shall be carried out in the same way as the first replacement area 101, with the replacement sequence starting from the collapse center line 3 and proceeding to both sides in sequence;

[0096] After all replacement zones are replaced and the structure is stable, clean the boreholes 10; prepare the stemming material 13 before drilling.

[0097] After approval from the public security department, a cordon was set up at the site. Before the overall blast, a test blast was conducted on the additional reinforced concrete support column 6 to adjust the blasting parameters. Then, the explosives were loaded, the blockage was sealed, and the wiring was connected to the detonation network. Finally, wire mesh was used for safety protection.

[0098] After all preparations are completed, the blasting site is cleared; the blasting is then detonated.

[0099] In the above method steps:

[0100] Preferably, the drilling direction of the retained area 102 is parallel to the direction of the retaining area 102 supporting the cylinder wall 1, and the drilling diameter is 40mm.

[0101] Optionally, the drilling direction of the reserved area 102 is perpendicular to the direction of the support cylinder wall 1 of the reserved area 102.

[0102] Preferably, the drilling time is selected after the formation of the doorway 2 and before the replacement of the axial pre-embedded hole reinforced concrete column support system.

[0103] Optionally, the drilling time is selected after the replacement of the axial pre-embedded hole reinforced concrete column support system is completed.

[0104] Preferably, a test blast is conducted on the additional axially pre-embedded holes 602 reinforced concrete support 6 before blasting to adjust the blasting parameters.

[0105] Preferably, the blasting charge uses high-efficiency emulsion explosive 11, with an explosive diameter of 32mm.

[0106] Preferably, the electronic detonator 12 is an industrial digital electronic detonator 12.

[0107] Preferably, all the electronic detonators 12 in the holes are detonated simultaneously.

[0108] This invention discloses a method for the blasting demolition of tall structures by replacing the supporting cylindrical wall 1 of the tall structure with an axially pre-embedded hole reinforced concrete column support system. Combined with axial charging blasting technology for the reinforced concrete columns 6, the demolition of the tall structure can be achieved by blasting only a few reinforced concrete columns 6. This reduces the amount of complex drilling work and significantly reduces the amount of plugging and protection work required for subsequent blasting. It also greatly improves the energy utilization rate of the explosive 11, reduces the consumption of explosive 11 and detonators, and significantly lowers demolition costs. Furthermore, the blasting with axially pre-embedded holes 602 arranged near the center of the structure results in more uniform fragmentation of the reinforced concrete columns 6, reducing blasting dust and making it more environmentally friendly. Therefore, this invention achieves the goals of safety, reliability, and environmental friendliness, and is applicable to the blasting demolition of tall structures such as chimneys and silos made of various materials including brick, concrete, and reinforced concrete, making its application very wide.

[0109] Implementation Case 1:

[0110] Taking a brick chimney with a height of 62.8m in a brick factory as an example, the surrounding environment of the chimney is complex, and the safety of the surrounding structures must be ensured. The construction is difficult. The outer diameter of the top of the chimney is 2.1m, the inner diameter is 1.86m, and the wall thickness is 240mm. The outer diameter of the bottom is 5m, the inner diameter is 3.56m, and the wall thickness is 720mm.

[0111] The axial pre-embedded hole reinforced concrete column support system is prefabricated, including: steel plate 5 with arc lengths of 1.8m and 2.0m, width of 0.72m, and thickness of 2cm; reinforced concrete column 6 with a column height of 1.8m, cross-sectional dimensions of 600×600mm, column head 601 with an outward expansion height of 200mm and an outward expansion width of 200mm; pre-embedded hole 602 with a vertical length of 1.5m, using PVC pipe with a wall thickness of 1mm and an outer diameter of 40mm, with an upper arc-shaped bend extending into column head 601, and an upper arc-shaped bend radius of 500mm; jack 8 with protective cover 7 with a total elevation of 40cm, a total height of 370mm, and a lifting height of 150mm; protective cover 7 with thicknesses of 20mm and 10mm, and a cross-sectional dimension of 650×650mm.

[0112] The above-mentioned construction method for demolishing chimneys by breaking through walls and replacing columns includes the following steps:

[0113] Based on the surrounding environment and the structural characteristics of the chimney, the direction of the chimney's collapse was determined; the required blasting cut for the chimney's collapse was calculated using empirical formulas, with a cut height of 2.2m, a cut width of 9.5m, and a corresponding angle of 220°.

[0114] The blasting cut was divided into three replacement zones 101 and two retention zones 102. The collapse centerline 3 was located in the first replacement zone 101, with the two sides being the second replacement zones 101. The width of the replacement zone 101 was 2.35 + 2.0 + 2.35 m, and the width of the retention zone 102 was 1.4 m. The chimney opening was located in the first replacement zone 101 to reduce the amount of excavation. After precise measurement, the exact locations of the replacement zone 101 and the retention zone 102 were marked with paint.

[0115] The non-structural lining inside the chimney was pre-removed; at the same time, shock-absorbing trenches were set up at the site in the direction of collapse.

[0116] The cylinder wall of the first replacement section 101 adjacent to the collapse center line 3 is broken with a crushing tool to form a doorway 2. Then, holes are drilled in the retained section 102, and the ground 4 and the upper edge of the cut are leveled to ensure good force transmission.

[0117] Place the two unlifted jacks 8 inside the protective cover 7 and position them precisely in the replacement area 101;

[0118] Use machinery to move the precast reinforced concrete support 6 onto the protective cover 7 and align it with the jack 8;

[0119] After the reinforced concrete support column 6 has been moved, place the steel plate 5 on the two reinforced concrete support columns 6;

[0120] Next, lift jack 8 until the axial pre-embedded hole reinforced concrete support system reaches the bearing requirements, then stop lifting to complete the replacement of the first replacement area 101.

[0121] The replacement of the remaining replacement areas 101 shall be carried out in the same manner as the first replacement area 101, with the replacement sequence starting from the collapse center line 3 and proceeding to both sides in sequence.

[0122] Drilling was performed after the replacement zone 101 was formed and before the axial pre-embedded hole reinforced concrete support system was replaced. Drilling was carried out on the retained zone 102 with a diameter of 40 mm and a depth of 1000 mm. The drilling direction was parallel to the support cylinder wall 1. One row of blast holes was drilled for each retained zone 102 with a spacing of 40 cm between the blast holes. After drilling was completed, the holes were cleaned and blasting mud 13 was prepared.

[0123] After completing the above preparations, the blasting operation was carried out. Explosive 11 was a high-performance emulsion explosive with a cartridge diameter of 32mm; electronic detonators 12 were millisecond-level industrial digital electronic detonators; there were 6 pre-embedded boreholes (602) with a single borehole charge of 0.324kg; and 10 boreholes with a single borehole charge of 0.050kg; the total explosive charge was 2.444kg. Each borehole used one electronic detonator 12, for a total of 16, detonated using MS3. The plugging length of the pre-embedded boreholes (602) was 0.785m; and the plugging length of borehole 10 was 0.2m.

[0124] After approval from the public security department, a cordon was set up at the site. Before the overall blast, a test blast was conducted on the additional reinforced concrete support 6 to adjust the blasting parameters. Then, explosives were loaded, the site was blocked, and the detonation network was connected. Finally, wire mesh was used for safety protection.

[0125] After all preparations are completed, the blasting site is cleared; the blasting is then detonated.

[0126] Implementation Case 2:

[0127] Taking a reinforced concrete chimney as an example, built in the 1990s, the chimney is 100m high, with an outer diameter of 8.0m at the bottom elevation of 0.0m, an outer diameter of 3.32m at the top, a wall thickness of 0.35m at the bottom, and gradually thickening to 0.8m from the bottom 1.2m to the bottom of the crossbeam at an elevation of 2.5m. The bottom 0.00 to 2.50m has no inner lining, refractory bricks, or insulation layer, while the insulation layer is 0.08m thick from the bottom 2.5 to 10m, and the inner lining is 0.24m thick.

[0128] The axial pre-embedded hole reinforced concrete column support system is prefabricated, including: steel plate 5 with arc lengths of 1.8m and 2.2m, width of 0.35m, and thickness of 2cm; reinforced concrete column 6 with a column height of 2.4m, cross-sectional dimensions of 350×350mm, column head 601 with an outward expansion height of 200mm and an outward expansion width of 200mm; pre-embedded hole 602 with a vertical length of 2m, using PVC pipe with a wall thickness of 1mm and an outer diameter of 30mm, with an upper arc-shaped bend extending into column head 601, and an upper arc-shaped bend radius of 400mm; jack 8 with protective cover 7 with a total elevation of 40cm, a total height of 370mm, and a lifting height of 150mm; protective cover 7 with thicknesses of 20mm and 10mm, and a cross-sectional dimension of 400×400mm.

[0129] The above-mentioned construction method for demolishing chimneys by breaking through walls and replacing columns includes the following steps:

[0130] Based on the surrounding environment and the structural characteristics of the chimney, the direction of the chimney's collapse was determined; the required blasting cut for the chimney's collapse was calculated using empirical formulas, with a cut height of 2.8m, a cut width of 15.0m, and a corresponding angle of 216°.

[0131] The blasting cut was divided into 7 replacement zones 101, with the collapse centerline 3 located in the first replacement zone 101. The width of the replacement zone 101 was 2.5 + 2.0 × 5 + 2.5 m. The chimney opening was located in the first replacement zone 101 to reduce the amount of excavation. After precise measurement, the exact locations of the replacement zone 101 and the retention zone 102 were marked with paint.

[0132] The non-structural lining inside the chimney was pre-removed; at the same time, shock-absorbing trenches were set up at the site in the direction of collapse.

[0133] The cylinder wall of the first replacement zone 101, which is adjacent to the collapse center line 3, is broken with a breaking tool to form a doorway 2. Then, holes are drilled in the retained zone 102 (the blast holes are perpendicular to the wall), and the ground 4 and the upper edge of the cut are leveled to ensure good force transmission.

[0134] Place the two unlifted jacks 8 inside the protective cover 7 and position them precisely in the replacement area 101;

[0135] Use machinery to move the precast reinforced concrete support 6 onto the protective cover 7 and align it with the jack 8;

[0136] After the reinforced concrete support column 6 has been moved, place the steel plate 5 on the two reinforced concrete support columns 6;

[0137] Next, lift jack 8 until the axial pre-embedded hole reinforced concrete support system reaches the bearing requirements, then stop lifting to complete the replacement of the first replacement area 101.

[0138] The replacement of the remaining replacement areas 101 shall be carried out in the same way as the first replacement area 101, with the replacement sequence starting from the collapse center line 3 and proceeding one by one to both sides.

[0139] After completing the above preparations, the blasting operation was carried out. The explosive 11 used was a high-performance emulsion explosive 11 with a cartridge diameter of 20mm. The electronic detonator 12 was a millisecond-level industrial digital electronic detonator 12. There were 14 pre-embedded boreholes (602), each with a charge of 0.176kg. The total explosive charge was 2.46kg. Each borehole used one electronic detonator 12, detonated using MS3, for a total of 16 boreholes. The plugging length of the pre-embedded boreholes (602) was 0.618m.

[0140] After approval from the public security department, a cordon was set up at the site. Before the overall blast, a test blast was conducted on the additional reinforced concrete support 6 to adjust the blasting parameters. Then, explosives were loaded, the site was blocked, and the detonation network was connected. Finally, wire mesh was used for safety protection.

[0141] After all preparations are completed, the blasting site is cleared; the blasting is then detonated.

[0142] Implementation Case 3:

[0143] Taking a certain chimney as an example, the chimney is 180m high and the body is made of C30 grade concrete. The outer diameter of the bottom and top is 16.6m and 5.8m respectively, and the wall thickness of the bottom and top is 460mm and 180mm respectively. At the bottom of the chimney at elevation 0, there are two 1.5×2.5m doorways in the north and south directions, with an outer diameter of 16.6m and a wall thickness of 460mm, without insulation layer or inner lining. At the chimney elevation of 8.1~13.7m, there are two 3.98×5.6m flue openings in the east and west directions, with an outer diameter of 15.2m and a wall thickness of 460mm. The insulation layer thickness is 100mm and the inner lining thickness is 240mm.

[0144] The axial pre-embedded hole reinforced concrete column support system is prefabricated, including: steel plate 5 with arc lengths of 1.8m and 2.2m, width of 0.50m, and thickness of 3cm; reinforced concrete column 6 with a column height of 4.1m, cross-sectional dimensions of 500×700mm, and an outer expansion height and width of 200mm for column head 601; pre-embedded hole 602 with a vertical length of 3.5m, using PVC pipe with a wall thickness of 1mm and an outer diameter of 40mm, with an upper arc-shaped bend extending into column head 601, and a radius of 550mm; jack 8 with protective cover 7 with a total elevation of 40cm, a total height of 370mm, and a lifting height of 150mm; protective cover 7 with thicknesses of 20mm and 10mm, and a cross-sectional dimension of 550×750mm.

[0145] The above-mentioned construction method for demolishing chimneys by breaking through walls and replacing columns includes the following steps:

[0146] Based on the surrounding environment and the structural characteristics of the chimney, the direction of the chimney's collapse was determined; the required blasting cut for the chimney's collapse was calculated using empirical formulas, with a cut height of 4.5m, a cut width of 31.1m, and a corresponding angle of 216°.

[0147] The blasting cut was divided into 9 replacement zones 101 and 8 preservation zones 102. The collapse centerline 3 was located in the first replacement zone 101, with the second, third, and fourth replacement zones 101 on either side. The width of replacement zone 101 was 2.0 + 2.5 × 7 + 2.0 m, and the width of preservation zone 102 was 1.2 m. The chimney opening was located in the first replacement zone 101 to reduce the amount of excavation. After precise measurement, the exact locations of replacement zone 101 and preservation zone 102 were marked with paint.

[0148] The non-structural lining and insulation layer inside the chimney will be pre-removed; at the same time, shock-absorbing trenches will be set up in the direction of the collapse.

[0149] The cylinder wall of the first replacement section 101 adjacent to the collapse center line 3 is broken with a crushing tool to form a doorway 2. Then, holes are drilled in the retained section 102, and the ground 4 and the upper edge of the cut are leveled to ensure good force transmission.

[0150] Place the two unlifted jacks 8 inside the protective cover 7 and position them precisely in the replacement area 101;

[0151] Use machinery to move the precast reinforced concrete support 6 onto the protective cover 7 and align it with the jack 8;

[0152] After the reinforced concrete support column 6 has been moved, place the steel plate 5 on the two reinforced concrete support columns 6;

[0153] Next, lift jack 8 until the axial pre-embedded hole reinforced concrete support system reaches the bearing requirements, then stop lifting to complete the replacement of the first replacement area 101.

[0154] The replacement of the remaining replacement areas 101 shall be carried out in the same manner as the first replacement area 101, with the replacement sequence starting from the collapse center line 3 and proceeding to both sides in sequence.

[0155] Drilling was performed after the replacement zone 101 was formed, but before the replacement of the axial pre-embedded hole reinforced concrete column support system. Drilling was carried out on the retained zone 102 with a diameter of 40 mm and a depth of 800 mm. The drilling direction was the long axis direction of the section of the retained zone 102, i.e., parallel to the support cylinder wall 1. One row of blast holes was drilled for each retained zone 102 with a spacing of 40 cm. After drilling was completed, the holes were cleaned and the blasting mud 13 was prepared.

[0156] After completing the above preparations, the blasting operation was carried out. Explosive 11 was a high-performance emulsion explosive with a cartridge diameter of 32mm; electronic detonators 12 were millisecond-level industrial digital electronic detonators; there were 16 pre-embedded boreholes (602), each with a charge of 0.861kg; and 1080 boreholes, each with a charge of 0.10kg; the total charge of explosive 11 was 21.776kg. Each borehole used one electronic detonator 12, totaling 96, and was detonated using MS3. The plugging length of pre-embedded borehole 602 was 0.864m; the plugging length of borehole 10 was 0.35m.

[0157] After approval from the public security department, a cordon was set up at the site. Before the overall blast, a test blast was conducted on the additional reinforced concrete support 6 to adjust the blasting parameters. Then, explosives were loaded, the site was blocked, and the detonation network was connected. Finally, wire mesh was used for safety protection.

[0158] After all preparations are completed, the blasting site is cleared; the blasting is then detonated.

[0159] Implementation Case 4:

[0160] Taking a single-cavity hollow brick tower as an example, the brick tower has 7 floors, a height of 18.032m, a hexagonal plan, a side length of 6.0m, and a wall thickness of 960mm.

[0161] The axial pre-embedded hole reinforced concrete column support system is prefabricated, including: steel plate 5 with a length of 2.6m, a width of 0.96m, and a thickness of 3cm; reinforced concrete column 6 with a height of 1.2m and 0.9m, a cross-sectional dimension of 900×900mm, an outer expansion height of 200mm for column head 601, and an outer expansion width of 200mm; pre-embedded holes 602 with vertical lengths of 0.8m and 0.5m, using PVC pipe with a wall thickness of 1mm and an outer diameter of 40mm, with an upper arc-shaped bend extending into column head 601, and an upper arc-shaped bend radius of 550mm; jack 8 with protective cover 7 with a total elevation of 40cm, a total height of 370mm, and a lifting height of 150mm; protective cover 7 with a thickness of 30mm and a cross-sectional dimension of 950×950mm.

[0162] The above-mentioned construction method for demolishing the brick tower by breaking through the wall and replacing the column includes the following steps:

[0163] Based on the surrounding environment and the structural characteristics of the brick tower, the direction of the brick tower's collapse was determined; the required blasting cut for the brick tower's collapse was calculated using empirical formulas, with a cut height of 1.6m and a cut width of 20m.

[0164] The blasting cut was divided into 3 replacement zones 101 and 6 retention zones 102. The collapse centerline 3 was located in the first replacement zone 101. The width of replacement zone 101 was 3.0 + 3.0 + 3.0m, and the width of retention zone 102 was 1.5m. The portal was located in the middle of replacement zone 101 to reduce the amount of excavation. After precise measurement, the exact locations of replacement zone 101 and retention zone 102 were marked with paint.

[0165] The non-structural lining inside the brick tower was pre-removed; at the same time, shock-absorbing trenches were set up at the site in the direction of collapse.

[0166] The cylinder wall of the first replacement section 101 adjacent to the collapse center line 3 is broken with a crushing tool to form a doorway 2. Then, holes are drilled in the retained section 102, and the ground 4 and the upper edge of the cut are leveled to ensure good force transmission.

[0167] Place the two unlifted jacks 8 inside the protective cover 7 and position them precisely in the replacement area 101;

[0168] Use machinery to move the precast reinforced concrete support 6 onto the protective cover 7 and align it with the jack 8;

[0169] After the reinforced concrete support column 6 has been moved, place the steel plate 5 on the two reinforced concrete support columns 6;

[0170] Next, lift jack 8 until the axial pre-embedded hole reinforced concrete support system reaches the bearing requirements, then stop lifting to complete the replacement of the first replacement area 101.

[0171] The replacement of the remaining replacement areas 101 shall be carried out in the same manner as the first replacement area 101, with the replacement sequence starting from the collapse center line 3 and proceeding to both sides in sequence.

[0172] Drilling was performed after the replacement zone 101 was formed, but before the replacement of the axial pre-embedded hole reinforced concrete column support system. Drilling was carried out on the retention zone 102 with a diameter of 40 mm and a depth of 1300 mm. The drilling direction was the long axis of the section of the retention zone 102, i.e., parallel to the support cylinder wall 1. Two rows of blast holes were drilled in one retention zone 102 with a blast hole spacing of 40 cm and a row spacing of 30 cm. After drilling was completed, the holes were cleaned and the blasting mud 13 was prepared.

[0173] After completing the above preparations, the blasting operation was carried out. Explosive 11 was a high-performance emulsion explosive with a cartridge diameter of 32mm; electronic detonators 12 were millisecond-level industrial digital electronic detonators; there were 6 pre-embedded boreholes (602), with single-hole charge amounts of 0.486kg and 0.365kg; 1040 boreholes, with a single-hole charge amount of 0.026kg; a total of 3.472kg of explosive 11; one electronic detonator 12 was used in each borehole, totaling 46, and MS3 detonation was employed; the plugging length of pre-embedded borehole 602 was 0.835m; the plugging length of borehole 10 was 0.3m.

[0174] After approval from the public security department, a cordon was set up at the site. Before the overall blast, a test blast was conducted on the additional reinforced concrete support 6 to adjust the blasting parameters. Then, explosives were loaded, the site was blocked, and the detonation network was connected. Finally, wire mesh was used for safety protection.

[0175] After all preparations are completed, the blasting site is cleared; the blasting is then detonated.

[0176] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for demolishing a structure by breaking through walls and replacing columns using a reinforced concrete column support system with axially embedded holes, characterized in that... Includes the following steps: Step 1: Set up a blasting cut below the support cylinder wall (1), and divide the support cylinder wall (1) within the blasting cut range into several replacement sections (101) and retention sections (102), wherein the replacement sections (101) and retention sections (102) are arranged at intervals. Step 2: Open blast holes (10) in the reserved area (102), then break up the replacement area (101) to form a doorway (2), and place an axially pre-embedded hole reinforced concrete support system in the doorway (2); The axial pre-embedded hole reinforced concrete column support system includes a steel plate (5), a reinforced concrete column (6), a protective cover (7), a jack (8) and a pad (9). The reinforced concrete column (6) is prefabricated and has a rectangular or circular cross-section. It includes a column head (601), a column body (603) and a pre-embedded hole (602) set in the middle of it. Step 3: Fill the pre-embedded hole (602) and the blast hole (10) with explosives (11) and block them with blasting mud (13), and at the same time lead out the detonator lead wire (14). Step 4: Connect all detonator leads (14) to form an initiation network, provide close-in protection for the reinforced concrete support column (6) and the reserved area (102), and finally activate the initiation network.

2. The method according to claim 1, wherein the method is characterized by, The substitution method in step two includes the following steps: S1, starting from the first replacement zone (101) immediately adjacent to the collapse centerline (3); S2, break the cylinder wall located in the first replacement zone (101) to form a doorway (2); S3. On the flat ground (4) below the replacement area (101), place the pad (9), jack (8), and protective cover (7) from bottom to top on the accurate position supported by the reinforced concrete column (6). S4. Move the precast reinforced concrete support (6) onto the protective cover (7); S5. Place the steel plate (5) on the reinforced concrete support (6); S6. Lift the jack (8) until the reinforced concrete support (6) reaches the bearing capacity requirement, then stop lifting and complete the replacement of the first replacement area (101). S7. Use the same method to complete the construction of the remaining replacement area (101), and the construction sequence is to proceed symmetrically to both sides of the collapse center line (3).

3. The method according to claim 1, wherein the method is characterized in that: In step two, the drilling direction of the retained area (102) is selected to be parallel to the support cylinder wall (1) of the retained area (102) or perpendicular to the support cylinder wall (1) of the retained area (102).

4. The method according to claim 2, wherein the method is characterized in that: The construction sequence of all replacement areas (101) is to start replacement from the first replacement area (101) adjacent to the collapse center line (3), and then replace it at intervals of several replacement areas (101) until all replacement areas (101) are replaced.

5. The method for demolishing a structure by breaking through walls and replacing columns using an axially pre-embedded hole reinforced concrete column support system according to claim 1, characterized in that: The column head (601) expands outward; The pre-embedded hole (602) is pre-embedded axially. The upper bend of the pre-embedded hole (602) bends up at the point where the cross-section of the reinforced concrete column (6) begins to expand. The pre-embedded hole (602) opens on the side surface of the column head (601) of the reinforced concrete column (6). The pad (9) is placed on the ground (4), the jack (8) is placed on the pad (9), the protective cover (7) is placed on the outside of the jack (8), the reinforced concrete support (6) is placed on the protective cover (7), and the steel plate (5) is placed on the top of the reinforced concrete support (6).

6. The method of breaking and removing a wall of a structure to replace columns with reinforced concrete column support system by blasting according to claim 1, characterized in that: The cross-sectional dimensions of the reinforced concrete column (6) are 300-1000mm, the height h of the column head (601) is 200-400mm, the width c of the column head (601) is 200-400mm, and the diameter of the pre-embedded hole (602) is 40-100mm.

7. The method according to claim 1, wherein the method is characterized in that: The protective cover (7) has a notch on its side, and the vertical bearing surface of the protective cover (7) is larger than the cross-sectional dimension of the column (603); the internal height of the protective cover (7) is not less than the minimum height of the jack (8).

8. The method of breaking wall and replacing column of the structure by using the reinforced concrete support system with axial pre-bored hole steel bar for blasting demolition according to claim 1, characterized in that: The width of a single replacement patch (101) is 1.2-3.0m, and the width of a single retention patch (102) is 1.0-3.0m.

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