Seismic wave cross-hole tomography detection boulder stratum underground diaphragm wall and construction method

Abstract

The invention relates to a seismic wave cross-hole tomography detection boulder stratum underground diaphragm wall and a construction method. The construction method comprises the following steps of boulder detection, blasting pre-decomposition punching of a bead-shaped boulder stratum, pressure and air release covering of a top opening of a blasting hole, and wall brushing and groove cleaning through a square hammer. The method has the advantages that the seismic wave cross-hole tomography equipment is utilized, dense detection paths are formed in the measurement area, then the boulder distribution condition in the measurement area is calculated and deduced, the method has the advantages of being good in reliability, high in intuition and high in accuracy, and efficient and high-quality diaphragm wall construction is guaranteed; the blasting hole drilling construction is performed after the boulder position information in the diaphragm wall range is detected, and then the explosive is loaded according to a discontinuous method, that is, the explosive is only placed at the boulder position, so that the purpose of pre-blasting decomposition is achieved, the grooving progress is greatly improved, the construction difficulty is reduced, and the stability of the groove wall is effectively guaranteed.

Description

Technical Field

[0001] The invention belongs to the field of underground continuous wall construction, and in particular relates to an underground continuous wall for detecting a boulder stratum by using seismic wave cross-hole tomography and a construction method. Background Art

[0002] With the development of urban construction, the utilization of urban underground space has received more and more attention. In the process of urban underground engineering development and construction, underground continuous wall is one of the forms of deep foundation pit support, which is widely used because of its good anti-seepage performance, high rigidity, high safety and reliability.

[0003] However, it is difficult to construct underground continuous walls in complex isolated rock formations, so it is difficult to ensure the construction progress and quality. During the construction of underground continuous walls, the problems of ground settlement, trenching difficulties, and easy collapse caused by isolated rocks have always been the key factors restricting the trenching of underground continuous walls. At the same time, due to the dense urban buildings, the vibration control and displacement settlement requirements of the construction process are high. The traditional underground continuous wall construction technology has been difficult to adapt to such complex geological and hydrological conditions, so higher requirements are put forward for the construction of underground continuous walls.

[0004] Therefore, it is of great significance to accurately explore boulder information and explore efficient boulder processing technology. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a seismic wave cross-hole tomography method for detecting an underground continuous wall in a boulder formation and a construction method thereof.

[0006] The construction method of the underground continuous wall for detecting the isolated rock formation by seismic wave cross-hole tomography includes the following construction steps: S1. Rock detection: bury the PE pipe and form a detection path in the measurement area through a one-shot-multiple-receiver fan-shaped penetration method to detect the location of the rock; S2. Pre-decomposition punching of beaded boulder formation by blasting: Arrange blasting holes and bury a PVC pipe with a sealed bottom, and place explosives in the PVC pipe corresponding to the position of the boulder; S3. Pressure relief and gas release covering at the top of the blasting hole: seal the PVC pipe, install the pressure relief and gas release covering device, apply pressure on the top of the pressure relief and gas release covering device and then carry out the blasting operation; S4. Use a square hammer to brush the wall and clean the groove: scrape away the debris on the I-beams at the joints of the groove sections and clean them up, then cast the ground-connected wall.

[0007] Preferably, step S1 comprises: S1.1. Drill holes in the ground at the construction location and bury the PE pipe; S1.2, place the transmitter and receiver into the PE pipes arranged on both sides of the boulder to form a detection path in the measurement area; S1.3, connecting the transmitter and the receiver to the transmitter and the receiver respectively, and connecting them to the terminal computer through a signal line to obtain measurement data; S1.4. Analyze the measurement data and detect the location of the isolated rock.

[0008] Preferably, the PE pipe is higher than the ground; the bottom of the PE pipe is completely sealed with a bottom sealing cover, and a top sealing cover is provided on the top of the PE pipe, and a signal line installation position is reserved on the top sealing cover.

[0009] Preferably, step S2 comprises: S2.1. Drill holes in isolated rocks as blasting holes; S2.2, placing a PVC pipe sealed with a bottom sealing cover in the blasting hole; S2.3. Install explosives in the PVC pipe according to the detected location of the boulder.

[0010] Preferably, for large boulders whose width is greater than the thickness of the ground-anchored wall, blasting holes are arranged in a plum blossom shape; for small boulders whose width is less than the thickness of the ground-anchored wall, blasting holes are arranged in a single row inside and empty holes are arranged on both sides of the small boulders.

[0011] Preferably, step S3 comprises: S3.1. Lead the detonating cord out of the blasting hole on the upper part of the PVC pipe and use fillers to block the upper cavity of the PVC pipe; S3.2. A bamboo cover is set at the ground surface of the hole opening, and a pressure relief and air release covering device is installed above the bamboo cover; and the steel plate of the pressure relief and air release covering device is pressurized by carrying sand bags.

[0012] Preferably, the pressure relief and air release covering device comprises a steel plate, a steel pipe, a top cover and a connector. The central opening of the steel plate is connected to the steel pipe. The top of the steel pipe is connected to the top cover via a connector. The sandbag is installed on the steel plate.

[0013] Preferably, the plugging height of the upper cavity of the PVC pipe blocked by the filler is controlled to be 4 to 5 m.

[0014] Preferably, step S4 comprises: S4.1. Use lifting equipment to lift the square hammer wall brush with the help of lifting rings; the square hammer wall brush is provided with an end scraper at one end and a wire brush at the other end; S4.2. Use the end scraper to brush the I-beam joint up and down; S4.3. Use a wire brush attached to the end to clean the inside of the I-beam joint.

[0015] Seismic wave cross-hole tomography for detecting underground continuous walls in boulder formations is obtained by any of the above-mentioned methods.

[0016] The beneficial effects of the present invention are: 1) The present invention proposes a seismic wave cross-hole tomography scanning boulder detection technology, which uses seismic wave cross-hole tomography equipment to form a dense detection path in the measurement area and then calculates and deduce the distribution of boulders in the measurement area. It has the characteristics of good reliability, strong intuitiveness and high accuracy, and ensures efficient and high-quality ground-connected wall construction.

[0017] 2) The present invention proposes a blasting pre-decomposition punching technology for beaded boulder formations. After detecting the location information of the boulders within the ground-connected wall, blasting hole drilling construction is carried out, and then explosives are loaded according to the intermittent method, that is, explosives are placed only at the locations of the boulders, thereby achieving the purpose of pre-blasting decomposition, greatly improving the trenching progress, reducing the construction difficulty, and effectively ensuring the stability of the trench wall.

[0018] 3) The present invention proposes a blasting hole top pressure relief and gas release covering technology, in which a bamboo cover is installed on the top of the blasting hole, and a pressure relief and gas release covering device is installed on the upper part by compacting with sand bags, so that the hole can filter most of the ejected fillings while relieving pressure and allowing air to pass through, and the fillings that cannot be filtered out are blocked by the top cover on the pressure relief and gas release covering device to prevent the fillings from splashing everywhere, thereby ensuring the safety of the operation while maintaining the civilized and environmentally friendly construction on site.

[0019] 4) The present invention proposes a square hammer wall brushing and trough cleaning technology. By processing and manufacturing a square hammer wall brush with a scraper and a wire brush, the inner and outer walls of the joint I-beam can be cleaned. The wall brush has a simple structure and is easy to manufacture. It saves construction costs and increases wall brushing efficiency while ensuring construction quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the seismic wave cross-hole tomography scanning boulder detection technology; Figure 2 This is the main view of the blast hole drilling construction; Figure 3 This is a schematic diagram of the installation of the curved steel plate on the drill pipe; Figure 4 This is a schematic diagram of the distribution of blasting holes for boulders of different thicknesses; Figure 5 This is a schematic diagram of the installation of beaded boulder explosives; Figure 6 It is a schematic diagram of the structure of the pressure relief and gas relief covering device; Figure 7 This is a schematic diagram of the pressure relief and gas release covering technology for the top of the blast hole; Figure 8 This is a top view of the square hammer wall brush; Fig. 9 This is the front view of the square hammer wall scrubber.

[0021] Explanation of the accompanying drawings: 1-computer, 2-signal line, 3-transmitter, 4-receiver, 5-ground, 6-transmitter, 7-PE pipe, 8-receiver, 9-top sealing cover, 10-boulder, 11-detection path, 12-bottom sealing cover, 13-arc steel plate, 14-drill rod, 15-drill hole, 16-drilling tool, 17-drill bit, 18-blasting hole, 19-ground connected wall, 20-empty hole, 21-large boulder, 22-small boulder, 23-detonating cord, 24-PVC pipe, 25-explosive, 26-upper boulder position, 27-lower boulder position, 28-steel plate, 29-steel pipe, 30-top cover, 31-connector, 32-bamboo cover, 33-filling, 34-square hammer wall brush, 35-lifting ring, 36-mud scraper, 37-arc steel plate, 38-wire brush. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for ordinary persons in the art, without departing from the principle of the present invention, the present invention can also be modified in some ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0023] Embodiment 1 As an example, Figures 1 to 9 As shown, the construction method of the underground continuous wall of the solitary rock formation using seismic wave cross-hole tomography includes the following construction steps: S1. Boulder detection: bury the PE pipe 7, and form a detection path 11 in the measurement area through a fan-shaped penetration method of one-shot and multiple-receiver to detect the position of the boulder 10; first, drill a hole at a specified position on the ground 5 on site, seal the bottom of the PE pipe 7 with a bottom sealing cover 12 and bury it in the hole, then put the transmitter 6 and the receiver 8 into the PE pipe 7 arranged on both sides respectively, use a data cable on site to connect the transmitter 6 and the receiver 8 with the transmitter 3 and the receiver 4, and finally connect them to the interface of the terminal computer 1, then start the equipment on site, and form a dense detection path 11 in the measurement area through the one-shot and multiple-receiver working mode of the transmitter 6 and the receiver 8, and use the measurement data obtained by the computer 1 to intuitively and accurately detect the position information of the boulder 10, and finally mark and record the position information of the boulder 10 at the current measurement location to facilitate subsequent processing and construction.

[0024] S2. Pre-decomposition punching of beaded boulder formation by blasting: After the detection work within the construction range of the local diaphragm wall 19 is completed, the blasting holes 18 are drilled on site according to the detection results, the blasting holes 18 are arranged and a PVC pipe 24 with a bottom seal is buried, and explosives 25 are placed in the PVC pipe 24 at the position corresponding to the boulder 10.

[0025] S3. Pressure relief and gas release covering at the top of the blasting hole: seal the PVC pipe 24, install a pressure relief and gas release covering device, apply pressure on the top of the pressure relief and gas release covering device, and then perform the blasting operation; S4. Use a square hammer to brush the wall and clean the groove: scrape away the debris on the I-beams at the joints of the groove sections and clean them up, then cast the ground-connected wall.

[0026] Embodiment 2 As another embodiment, this embodiment 2 proposes, based on the embodiment 1, a more specific construction method of underground continuous wall detection in isolated rock formation by using seismic wave cross-hole tomography: like Figure 1 As shown, first, a PE pipe 7 is buried in the ground 5 near the detection area. The buried PE pipe 7 is 50.5m above the ground and is well protected. Then, the transmitter 6 and the receiver 8 are placed in the PE pipe 7 arranged on both sides, and the transmitter 6 and the receiver 8 are connected to the transmitter 3 and the receiver 4 respectively, and finally connected to the terminal computer 1 using the signal line 2. Then, the device is started to control the field measurement and data transmission through the computer 1. Through the fan-shaped penetration mode of one send and multiple receive, a dense detection path 11 is formed in the measurement area. Finally, the location information of the isolated rock 10 is intuitively and accurately detected by calculation and analysis with the help of measurement data, and marked and recorded for subsequent processing.

[0027] like Figures 2 to 5 As shown, after the on-site detection is completed, the blasting hole 18 drilling 15 is constructed. First, the arc steel plate 13 is installed on the drill rod 14 of the drilling rig to ensure that the verticality can be guaranteed during construction. The boulders within the slot section of the ground-connected wall 19 are cored and drilled by the lower drilling tool 16 and the drill bit 17. The blasting holes 18 are arranged in a targeted manner for large boulders 21 and small boulders 22 of different widths. Then, after the blasting holes 18 are formed, the PVC pipe 24 is placed in the blasting hole 18, and the bottom of the pipe is sealed with a bottom sealing cover 12. Subsequently, the explosives 25 are intermittently installed at the upper boulder position 26 and the lower boulder position 27 according to the distribution of the string-like boulders. Finally, after all the work arrangements on the site are completed, the professionals detonate and decompose the boulders through the detonating cord 23.

[0028] In step S2, firstly, an arc-shaped steel plate 13 is installed on the outside of the drill rod 14 of the drilling rig to ensure the verticality of the hole, so as to avoid the path deviation when the lower drilling tool 16 and the drill bit 17 are coring and drilling the isolated rocks within the slot section of the ground-connected wall 19. Then, the blasting holes 18 are arranged according to the situation of the isolated rocks invading the ground-connected wall. For large isolated rocks 21 with a width greater than the thickness of the ground-connected wall 19, the blasting holes 18 are arranged in a plum blossom shape with a spacing of 1.0 m in three rows, and for small isolated rocks with a width less than the thickness of the ground-connected wall 19, the blasting holes 18 are arranged in a plum blossom shape with a spacing of 1.0 m in three rows. Blasting holes 18 are arranged in a single row inside the stone 22, and empty holes 20 are arranged on both sides to facilitate the loosening and displacement of the small boulders 22 to both sides when blasting. Then, the bottom of the PVC pipe 24 is sealed with a bottom sealing cover 12 and buried in the middle blasting hole 18. Explosives 25 are placed intermittently according to the specific upper and lower boulder positions 26 and 27, so that the explosives 25 are only placed at the boulder positions. Finally, the detonating cord 23 is led out of the ground 5, and the next step of blasting hole 18 mouth treatment is carried out.

[0029] It should be noted that the parts in this embodiment that are the same or similar to those in the first embodiment can be referenced to each other and will not be described in detail in this application.

[0030] Embodiment 3 As another embodiment, this embodiment 3 proposes, based on the first and second embodiments, a more specific construction method of underground continuous wall detection in isolated rock formation by using seismic wave cross-hole tomography: In step S3, before the blasting construction, a pressure relief and air release covering device is customized in the production plant, which is mainly composed of a steel plate 28, a steel pipe 29, a top cover 30, and a connector 31 fixedly connected. When the blasting hole 18 is processed, the upper cavity of the PVC pipe 24 is first blocked with a filler 33. When the filler 33 is used to block the upper cavity of the PVC pipe 24, the blocking height is controlled at 4 to 5 meters. Then, a woven bamboo cover 32 is installed at the ground 5 of the orifice, so that the orifice can filter most of the orifice fillers 33 ejected by the blasting while maintaining pressure relief and air permeability. The fillers that cannot be filtered out are blocked by the top cover 30 on the pressure relief and air release covering device. Then, the customized pressure relief and air release covering device is installed above the bamboo cover 32, and multiple bags of sand bags 31 are moved and pressed on the bottom steel plate 28 of the pressure relief and air release covering device. Finally, professionals perform blasting operations on site through the detonating tube 23. After the blasting is completed, the site is cleaned up and subsequent operations are carried out. A gap is left between the top cover 30 of the pressure relief and gas relief covering device and the steel pipe 29, which can facilitate the extraction of the detonating tube 23 while relieving pressure and gas and preventing the explosives from splashing.

[0031] like Figure 6 and Figure 7As shown, before the blasting construction, first use the filler 33 to block the upper cavity of the PVC pipe 24, then install the woven bamboo cover 32 at the ground 5 of the hole of the PVC pipe 24, and lead the detonating tube 23 out of the hole at the top, then install the pressure relief and gas covering device above the bamboo cover 32, and move the sandbag 31 to press on the steel plate 28 of the pressure relief and gas covering device. During blasting, the bamboo cover 32 is used in conjunction with the pressure relief and gas covering device and the sandbag 31 to prevent the filler 33 from blasting and splashing, and finally the blasting operation is carried out through the detonating tube 23, and the site is cleaned up after the blasting is completed.

[0032] In step S4, when cleaning the slot section joints, firstly, a square hammer wall brush 34 with a scraper 36 and a wire brush 38 is manufactured, and then the on-site lifting equipment uses the lifting ring 35 on the top of the square hammer wall brush 34 to lift it into the slot section, and then use the end scraper 36 to brush the slot section joint up and down to scrape off the debris on the joint I-beam, and finally use the end with a wire brush 38 to carefully clean the debris on the inner wall of the I-beam joint, and after cleaning, the pouring construction of the ground-connected wall is carried out.

[0033] like Figure 8 and Fig. 9 As shown, during the cleaning of the slot joints, a square hammer wall brush 34 is used to clean the joints up and down. First, the square hammer wall brush 34 is manufactured and transported to the construction site. Then, a lifting device is used on site to lift the square hammer wall brush 34 with the help of a lifting ring 35. Then, the end scraper 36 is used to brush the I-beam joint up and down to remove debris from the joint. Finally, the end with a wire brush 38 is used to carefully clean the inner wall of the I-beam joint.

[0034] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

Claims

1. A construction method for detecting underground continuous walls in isolated rock formations by using seismic wave cross-hole tomography, characterized in that: The construction steps include: S1. Rock detection: bury the PE pipe and form a detection path in the measurement area through a one-shot-multiple-receiver fan-shaped penetration method to detect the location of the rock; S2. Pre-decomposition punching of beaded boulder formation by blasting: Arrange blasting holes and bury a PVC pipe with a sealed bottom, and place explosives in the PVC pipe corresponding to the position of the boulder; S3. Pressure relief and gas release covering at the top of the blasting hole: seal the PVC pipe, install the pressure relief and gas release covering device, apply pressure on the top of the pressure relief and gas release covering device and then carry out the blasting operation; S4. Use a square hammer to brush the wall and clean the groove: scrape away the debris on the I-beams at the joints of the groove sections and clean them up, then cast the ground-connected wall.

2. The construction method of detecting underground continuous wall in boulder formation by seismic wave cross-hole tomography according to claim 1 is characterized in that: Step S1 includes: S1.

1. Drill holes in the ground at the construction location and bury the PE pipe; S1.2, place the transmitter and receiver into the PE pipes arranged on both sides of the boulder to form a detection path in the measurement area; S1.3, connecting the transmitter and the receiver to the transmitter and the receiver respectively, and connecting them to the terminal computer through a signal line to obtain measurement data; S1.

4. Analyze the measurement data and detect the location of the isolated rock.

3. The construction method of detecting underground continuous wall in boulder formation by seismic wave cross-hole tomography according to claim 2 is characterized in that: The PE pipe is higher than the ground; the bottom of the PE pipe is completely sealed with a bottom sealing cover, and a top sealing cover is arranged on the top of the PE pipe, and a signal line installation position is reserved on the top sealing cover.

4. The construction method of detecting underground continuous wall in boulder formation by seismic wave cross-hole tomography according to claim 1 is characterized in that: Step S2 includes: S2.

1. Drill holes in isolated rocks as blasting holes; S2.2, placing a PVC pipe sealed with a bottom sealing cover in the blasting hole; S2.

3. Install explosives in the PVC pipe according to the detected location of the boulder.

5. The construction method of detecting underground continuous wall in boulder formation by seismic wave cross-hole tomography according to claim 4 is characterized in that: For large boulders whose width is greater than the thickness of the ground-anchored wall, blasting holes are arranged in a plum blossom shape; for small boulders whose width is less than the thickness of the ground-anchored wall, blasting holes are arranged in a single row inside and empty holes are arranged on both sides of the small boulders.

6. The construction method of detecting underground continuous wall in boulder formation by seismic wave cross-hole tomography according to claim 1 is characterized in that: Step S3 includes: S3.

1. Lead the detonating cord out of the blasting hole on the upper part of the PVC pipe and use fillers to block the upper cavity of the PVC pipe; S3.

2. A bamboo cover is set at the ground surface of the hole opening, and a pressure relief and air release covering device is installed above the bamboo cover; and the steel plate of the pressure relief and air release covering device is pressurized by carrying sand bags.

7. The construction method of detecting underground continuous wall in boulder formation by seismic wave cross-hole tomography according to claim 6 is characterized in that: The pressure relief and air release covering device comprises a steel plate, a steel pipe, a top cover and a connecting piece. The central opening of the steel plate is connected to the steel pipe, the top of the steel pipe is connected to the top cover through the connecting piece, and the sand bag is installed on the steel plate.

8. The construction method of detecting underground continuous wall in boulder formation by seismic wave cross-hole tomography according to claim 6 is characterized in that: The plugging height of the upper cavity of the PVC pipe blocked by the filler is controlled to be 4 to 5 m.

9. The construction method of detecting underground continuous wall in boulder formation by seismic wave cross-hole tomography according to claim 1, characterized in that: Step S4 includes: S4.

1. Use lifting equipment to lift the square hammer wall brush with the help of lifting rings; the square hammer wall brush is provided with an end scraper at one end and a wire brush at the other end; S4.

2. Use the end scraper to brush the I-beam joint up and down; S4.

3. Use a wire brush attached to the end to clean the inside of the I-beam joint.

10. Seismic wave cross-hole tomography detection of underground continuous walls in isolated rock formations, characterized in that: Obtained by the method according to any one of claims 1 to 9.

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