Stone stratum roadbed non-blasting excavation construction method

Abstract

The invention discloses a stone stratum roadbed non-blasting excavation construction method which comprises the following steps: S1, before high slope excavation construction, finishing a construction working face platform; s2, holes are drilled in preset point positions of the construction working face of the slope platform according to the specified depth, and expansion pipes of the specified size are placed in the holes; s3, backfilling gravel at the drill hole, blocking the hole opening, and rechecking the expansion pipe lead; s4, arranging an earth surface protection facility on the slope platform; s5, stone cracking is conducted through the thermal expansion reaction of the expansion pipe; s6, surface protection facilities are removed, and expansion pipe firecracker arrangement inspection is carried out; s7, the stones on the construction site are mechanically reduced and chiseled away; and S8, the operations of S2-S7 are repeated on the next-stage slope platform until all the slope platforms are excavated. By arranging the three-stage earth surface protection facility, rolling stones and splashes can be intercepted layer by layer, so that a multi-stage safety barrier is constructed, and the driving safety close to an operation highway is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of engineering excavation construction, and in particular to a non-blasting excavation construction method for a rocky stratum roadbed. Background Art

[0002] In mountain highway reconstruction and expansion projects, rock slope excavation construction faces challenges such as complex terrain, variable geological conditions, steep slopes and limited construction space.

[0003] At the same time, the following problems still exist in the excavation of rock slopes for the reconstruction and expansion of some mountainous highways: (1) It is difficult to build a construction access road on the high slope; (2) The rock excavation is close to the operating highway, which has a high safety risk. At the same time, the minimum width of the opening line from the highway road surface is about 30m, which makes it difficult to control the safety of the excavation process; (3) The working surface is narrow, the rock volume is huge, and the excavation efficiency is extremely low.

[0004] To this end, the present application proposes a non-blasting excavation construction method for rocky stratum roadbed to solve the above technical problems. Summary of the Invention

[0005] The main purpose of the present invention is to provide a non-blasting excavation construction method for a rocky stratum roadbed to solve the technical problems raised in the background technology.

[0006] The present invention adopts the following technical solutions to solve the above technical problems:

[0007] A non-blasting excavation construction method for a rocky stratum roadbed comprises:

[0008] S1. Before excavation of high slopes, repair the construction working surface platform;

[0009] S2. Drill holes at a specified depth at preset points on the slope platform and insert expansion tubes of specified sizes;

[0010] S3. Backfill the drilled hole with gravel and seal the hole opening, and recheck the expansion tube lead wire;

[0011] S4. Install surface protection facilities on the slope platform;

[0012] S5. Control the thermal expansion reaction of the expansion tube by the expansion tube lead to crack the rock;

[0013] S6. Remove surface protection facilities and conduct an inspection of the expansion tube blasting;

[0014] S7. Mechanically break down and remove rocks at the construction site;

[0015] S8. Repeat S2-S7 on the next slope platform until all slope platforms are excavated.

[0016] Preferably, in step S2, the length of the construction working surface is set to 6m, a protective wall is set within 1.5-2.5m from the old slope, and a mechanical slope repair is set within 1-1.5m from the new slope, without drilling and blasting.

[0017] Preferably, during the operation of step S2, the number of holes laid out in a single construction is set to a maximum of 9, arranged in a plum blossom shape, with 2 rows set in front and back, the hole spacing is set to 2*2m, the hole depth is set to 6m, and the drilling diameter is set to 11.5cm.

[0018] Preferably, during the operation of step S2, the drilling depth is set to 6 m, the expansion tube is vertically placed at the bottom of the hole, and the distance from the top of the expansion tube to the hole mouth is set to be no less than 4.5 m.

[0019] Preferably, in step S4, a covering steel plate and a protective shed are used for surface protection, wherein:

[0020] The thickness of the covering steel plate is set to 2 cm, leaving a gap of about 20 cm between the steel plate and the ground surface, and the range of the steel plate covering and protecting exceeds the boundary of the working area by at least 50 cm;

[0021] The protective shed is assembled with steel pipe fasteners, and two layers of wire mesh are laid on the outside. The four corners of the protective shed are anchored to the counterweight pier with steel wire ropes. The steel pipe is set as the inner skeleton, and the mesh surface is a layer of high-strength steel rope diamond mesh and a layer of steel wire mesh with a pore size of 10mm.

[0022] Preferably, the specific operation process of step S4 includes:

[0023] S41. Install colored steel plates to enclose the debris platform at the foot of the slope to isolate the area;

[0024] S42. Install passive protective nets on both the first bottom platform and the top platform to prevent rockfall.

[0025] S43. Install a steel pipe protective net on the outer platform of the excavation surface to prevent flying rocks.

[0026] Preferably, in step S5, a thermal expansion agent and an ignition tube are provided in the expansion tube, and the ignition tube lead extends to the outside of the expansion tube and is used to ignite the ignition tube in the expansion tube.

[0027] As can be seen from the above technical solution, the present invention provides a non-explosive excavation construction method for roadbed in rocky strata. Compared with the existing technology, the present invention has the following advantages:

[0028] 1. The present invention sets up three levels of surface protection facilities (color steel plate enclosure, passive protection net, steel pipe protection net), which can intercept rolling stones and flying objects layer by layer, thereby building a multi-level safety barrier to ensure driving safety near the operating highway.

[0029] 2. The present invention arranges 9 drill holes in a plum blossom shape with a hole spacing of 2×2 meters and a hole depth of 6 meters to form a uniformly distributed fracture network, thereby maximizing the rock crushing effect.

[0030] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become easy to understand through the following description. Of course, it is not necessary to achieve all of the above-mentioned advantages simultaneously in order to implement any product of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 It is a schematic diagram of the overall construction process of the present invention;

[0033] Figure 2 A schematic diagram of a temporary protection arrangement according to the present invention;

[0034] Figure 3 Detailed diagram of the temporary protection net installation in the present invention Figure 1 ;

[0035] Figure 4 Detailed diagram of the temporary protection net installation in the present invention Figure 2 ;

[0036] Figure 5 Detailed diagram of the temporary protection net installation in the present invention Figure 3 ;

[0037] Figure 6 Schematic diagram of the cross section of the excavation range of the present invention;

[0038] Figure 7 Schematic diagram of the cross section of the hole arrangement of the present invention;

[0039] Figure 8 This is a schematic diagram of the hole arrangement plane of the present invention;

[0040] Figure 9 It is a schematic diagram of the surface protection of the present invention. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0042] In the embodiment, see Figures 1 to 9 .

[0043] like Figure 1 A non-explosive excavation construction method for a rocky stratum roadbed proposed in an embodiment of the present invention includes:

[0044] S1. Before excavating high slopes, repair the construction work surface platform.

[0045] At this time, by repairing the construction working surface platform before excavating the high slope, a stable working space can be provided for subsequent drilling, rock cracking and mechanical dismantling, thereby improving construction efficiency and ensuring project progress.

[0046] S2. Drill holes at specified depths at preset points on the construction work surface of the slope platform, and insert expansion tubes of specified sizes. This allows for precise control of the rock cracking range and force, effectively crushing high-strength rock (compressive strength above 100 MPa) and achieving efficient excavation without blasting.

[0047] In order to avoid the large impact force during thermal expansion reaction and the resulting flying rock accidents, the number of holes in a single construction is set to a maximum of 9, arranged in a plum blossom shape, with 2 rows in front and back, the hole spacing is set to 2×2m, the hole depth is set to 6m, the drilling diameter is set to 11.5cm, and the drilling depth is set to 6m. The expansion tube is placed vertically at the bottom of the hole, and the distance from the top of the expansion tube to the hole mouth is set to not less than 4.5m. At this time, a uniformly distributed crack network can be formed, thereby maximizing the rock crushing effect, increasing the daily excavation volume to 3-5 times that of the traditional process, and effectively absorbing the impact energy, thereby controlling the impact range of flying rocks within 10 meters, so that the safety warning zone is set 20 meters away to meet the protection needs.

[0048] Furthermore, the length of the construction working surface is set to 6m, a protective wall is set up within 1.5-2.5m from the old slope, and mechanical slope repair is set up within 1-1.5m from the new slope. No drilling or blasting is performed to avoid excessive thermal expansion reaction.

[0049] Furthermore, the expansion tube of the present application uses a thermal expansion agent whose raw materials include potassium perchlorate and sodium nitrite. During actual use, the gas expansion operation is quickly performed through the thermal reaction of potassium perchlorate and sodium nitrite.

[0050] In a specific embodiment, a 2×2m plum blossom-shaped hole layout, a 6m deep hole with an 11.5cm aperture design, combined with potassium perchlorate + sodium nitrite expansion agents, can form a uniform fracture network, and the daily excavation volume can reach 3-5 times that of traditional processes.

[0051] In addition, during a specific implementation operation, drilling was carried out strictly according to the designed hole spacing in the early stage. During construction, it was found that the expansion effect of the rock layer with developed cracks was not ideal, but the expansion effect of the whole rock mass was better. In other words, the faults, joints, and cracks in the mountain rock layer affected the rock splitting effect. After analysis, it was found that there were a large number of structural weak surfaces such as faults, joints, and cracks in the mountain rock layer. The shock wave generated by thermal expansion would attenuate sharply during the propagation process, resulting in energy loss and uneven distribution. These structural weak surfaces prevented the energy from being evenly distributed, thus affecting the blasting effect. Therefore, the following improvement measures were proposed:

[0052] ① In the hole layout design, try to arrange the blast holes perpendicular to the weak surface of the structure. This can reduce energy loss and improve the blasting effect.

[0053] ② When encountering a situation with interlayers, appropriately increasing the charge (using a 1.5m expansion tube) can compensate for energy loss and improve the blasting effect.

[0054] ③ When the blast hole is parallel to the weak surface of the structure, try to reduce the blast hole distance to improve the blasting effect.

[0055] Furthermore, especially for strata with developed faults / joints, measures such as vertical weak surface drilling, increasing the length of 1.5m expansion tubes in the interlayer section, and increasing the spacing between parallel weak surface holes were adopted to increase the qualified rate of crushing high-strength rock (>100MPa) from 60% to 95%.

[0056] In addition, in a specific implementation operation, it is also necessary to note that the expansion tube cannot be lowered immediately after drilling is completed; in order to ensure the safety and controllability of the construction process, the expansion tube can only be lowered after the hole has cooled down to ensure the cooling of the inside of the blasthole and avoid excessive temperature in the hole, which may cause accidental explosion.

[0057] S3. Backfill the drilled hole with gravel and seal the hole opening, and recheck the expansion tube leads. This ensures the tightness of the expansion tube's thermal expansion reaction, thereby avoiding energy loss and the risk of flying rocks, and improving process safety.

[0058] After the expansion tube is installed, lead the expansion tube lead (power sensor line) out of the hole and detect the current value of the expansion tube lead (power sensor line) to be 3-7 mA, which means the line is normal.

[0059] The hole should be filled with sand at a depth of no less than 4.5m, and sandbags should be used to seal the hole opening.

[0060] S4. Install surface protection facilities on the slope platform.

[0061] At this time, steel plates and protective sheds are used for surface protection, including:

[0062] The thickness of the covering steel plate is set to 2cm, leaving a gap of about 20cm between the steel plate and the ground surface. The scope of the steel plate's protection exceeds the boundary of the working area by at least 50cm;

[0063] refer to Figure 9 The shelter is assembled using steel pipe fasteners, with two layers of wire mesh laid on the outside. The four corners of the shelter are anchored to the counterweight piers with wire ropes. The steel pipes serve as the inner frame, and the mesh consists of a high-strength diamond-shaped steel rope mesh and a 10mm-diameter wire mesh. Furthermore, to prevent flying rocks from the free surface, the mesh needs to be extended to cover the entire free surface.

[0064] In addition, in a specific implementation operation, after the expansion tube was installed, sand was used to fill the hole without compaction, which affected the rock cracking effect. After analysis, it was found that the main function of filling the hole with sand was to prevent the vertical impact force from pushing the expansion tube upward when the expansion tube reacted, resulting in the lack of energy concentration at the bottom, which affected the rock cracking effect. Therefore, it was necessary to increase the filling density in the hole to improve the rock cracking effect. Therefore, the following improvement measures are proposed:

[0065] ①Fill the hole with sand and backfill in layers. The height of each layer should be controlled at about 1m and compacted with bamboo poles.

[0066] ② To improve the quality of the filling material in the hole, you can add melon stone to the sand to improve the backfill quality.

[0067] In addition, since the impact force of expansion blasting will not exceed 10m, a safety cordon needs to be set up 20m outside the working area.

[0068] At this time, before the excavation of the high slope, the surface protection facilities of the slope adopt three levels of protection measures. That is:

[0069] First, as Figure 2 and Figure 5 As shown, a color steel plate enclosure is set up at the debris platform at the foot of the slope to isolate the closed area;

[0070] like Figure 2 and Figure 4 As shown, passive protection nets are installed on both the first-level platform and the uppermost platform to prevent rolling stones from sliding (the passive protection nets above the first-level platform are recycled and removed and installed on the next level after the excavation of the previous level is completed);

[0071] like Figure 2 and Figure 3As shown, a steel pipe protective net is set on the platform outside the excavation surface to prevent flying rocks (one layer of protective net is excavated, the original protection is removed, and a new protection is installed on the new excavation surface).

[0072] By installing three levels of surface protection (color-coated steel plate enclosures, passive protective nets, and steel pipe protective nets), rolling rocks and flying debris are intercepted layer by layer, creating a multi-level safety barrier to ensure driving safety near the operational highway. By limiting the length of a single rock-breaking operation to 6 meters and establishing protective walls and mechanical slope repair areas, the energy release range is limited, thus avoiding disturbance of both the existing and new slopes, ensuring slope stability and controllable construction. Passive protective nets are cyclically installed and removed with each excavation level, and steel pipe protective nets are relocated in layers, improving the utilization of protective resources. Furthermore, through the cycle of "protection facility installation and removal - rock-breaking - dismantling - platform lowering," the slope deformation gradient is controlled.

[0073] S5. Control the thermal expansion reaction of the expansion tube through the expansion tube lead to crack the rock.

[0074] A thermal expansion agent and an ignition tube are provided in the expansion tube, and the ignition tube lead extends to the outside of the expansion tube and is used for igniting the ignition tube in the expansion tube.

[0075] In addition, in a specific implementation operation, during the early construction, the length of the thermal expansion range reached more than 10m. Due to the restriction that the amount of expansion agent cannot be too large, the clamping effect of the mountain rock layer is large, and the rock cracking effect is not ideal. After analysis, the thermal expansion range is large, the clamping effect of the mountain rock layer during thermal expansion is large, and the large amount of rock can effectively resist the impact force during thermal expansion, consuming the energy of the thermal expansion reaction, thereby affecting the blasting effect. Therefore, it is necessary to create an open surface to improve the rock cracking effect. For this purpose, the following improvement measures are proposed:

[0076] like Figure 6 、 Figure 7 and Figure 8 As shown, before the first thermal expansion operation, mechanical chiseling can be used to create an open surface to improve the rock splitting effect. Alternatively, thermal expansion reaction can be used to create an open surface. Oblique drilling can be used (with the hole opening away from the high-speed direction), the amount of thermal expansion agent can be reduced, and the vertical depth of the drilling can be controlled at around 4m. Alternatively, the first row of holes can be shortened and the charge appropriately increased, followed by a normal hole spacing and micro-difference blasting. This can form a larger blasting funnel, add an open surface, and fully crush the rock. In summary, this can effectively break the mountain clamping effect and increase crushing efficiency by more than 40%.

[0077] Considering the safety of high-speed driving, only one free-facing surface is set up, and it is arranged parallel to the direction of high-speed driving.

[0078] S6. Remove the surface protection facilities and conduct an inspection of the expansion tube blasting.

[0079] Specifically, after blasting, the current of the power supply sensor line is detected. If the test current value of the power supply sensor line is zero, there is no blind shot.

[0080] Furthermore, through the dual verification mechanism of current detection and sandbag sealing, the completion status of the rock cracking reaction can be accurately judged, thereby eliminating the hidden dangers of blind shots and achieving zero-accident safe construction.

[0081] S7. Stones at the construction site shall be mechanically broken down and removed.

[0082] S8. Repeat S2-S7 on the next slope platform until all slope platforms are excavated.

[0083] At this time, the recycling of protective facilities can reduce material loss and construction costs, thereby optimizing resource allocation and achieving project progress goals while ensuring safety.

[0084] In addition, during a specific implementation operation, because the construction was carried out during the rainy season, there was a lot of groundwater in the cracks of the mountain. The drainage and precipitation measures were not in place, which affected the reaction effect of the expansion agent and the rock cracking effect was not ideal. Since the main reaction agents of the thermal expansion agent are potassium perchlorate and sodium nitrite, both of which are hygroscopic and easily soluble in water, there is water accumulation inside the blasthole, which reduces the reaction effect of the expansion agent. Therefore, it is necessary to ensure that the blasthole is dry to improve the expansion reaction effect. There are the following improvement measures:

[0085] ① Try to drill on a sunny day. If there is a lot of water in the hole, the hole must be drained and dried first.

[0086] ② Improve the sealing performance of the expansion tube and use sealing tape to seal the sealing joint to prevent water from entering the tube.

[0087] ③ During construction in the rainy season, the water accumulation in the blasthole should be checked in advance. If there is a lot of water, additional drainage channels can be added on the air-facing surface.

[0088] In summary, during the specific implementation process, a three-dimensional protection network was established through plum blossom-shaped hole arrangement (≤9 holes per time), 4.5m sand and gravel compaction and sealing of the hole mouth, 20cm gap steel plate covering, three-level protection facilities (color steel plate enclosure + passive protection net + steel pipe protection net) and 20m safety warning line setting, so that the impact range of flying rocks is strictly controlled within 10m, and the safety warning distance is reduced to 1 / 5 of traditional blasting.

[0089] Therefore, this method overcomes the technical bottlenecks of low efficiency, poor safety and weak geological adaptability of traditional non-blasting processes through the innovative "energy constraint-dynamic protection-intelligent monitoring" technical system, and can be successfully applied in complex geological roadbed projects adjacent to operating roads.

[0090] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0091] In addition, it should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0092] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or schemes in which A and B are satisfied at the same time. In addition, in the embodiments of the present invention, "multiple" refers to more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A non-blasting excavation construction method for a rocky stratum roadbed, characterized in that: include: S1. Before excavation of high slopes, repair the construction working surface platform; S2. Drill holes at a specified depth at preset points on the slope platform and insert expansion tubes of specified sizes; S3. Backfill the drilled hole with gravel and seal the hole opening, and recheck the expansion tube lead wire; S4. Install surface protection facilities on the slope platform; S5. Control the thermal expansion reaction of the expansion tube by the expansion tube lead to crack the rock; S6. Remove surface protection facilities and conduct an inspection of the expansion tube blasting; S7. Mechanically break down and remove rocks at the construction site; S8. Repeat S2-S7 on the next slope platform until all slope platforms are excavated.

2. The non-explosive excavation construction method for rocky stratum roadbed according to claim 1, characterized in that: The specific operation process of step S1 includes: S11. Install colored steel plates to enclose the debris platform at the foot of the slope to isolate the area; S12. Install passive protection nets on both the first bottom platform and the top platform to prevent rocks from falling. S13. Install a steel pipe protective net on the outer platform of the excavation surface to prevent flying rocks.

3. The non-explosive excavation construction method for rocky stratum roadbed according to claim 1, characterized in that: In the step S2, the length of the construction working surface is set to 6m, the range 1.5-2.5m away from the old slope is set as a protective wall, and the range 1-1.5m away from the new slope is set as mechanical slope repair, and no drilling and blasting are performed.

4. The non-blasting excavation construction method for rocky stratum roadbed according to claim 1, characterized in that: During the operation of step S2, the number of holes laid out in a single construction is set to a maximum of 9, arranged in a plum blossom shape, with 2 rows set in front and back, the hole spacing is set to 2*2m, the hole depth is set to 6m, and the drilling diameter is set to 11.5cm.

5. The non-explosive excavation construction method for rocky stratum roadbed according to claim 1, characterized in that: During the operation of step S2, the drilling depth is set to 6m, the expansion tube is vertically placed at the bottom of the hole, and the distance from the top of the expansion tube to the hole mouth is set to be no less than 4.5m.

6. The non-blasting excavation construction method for rocky stratum roadbed according to claim 1, characterized in that: In step S4, a covering steel plate and a protective shed are used for surface protection, wherein: The thickness of the covering steel plate is set to 2 cm, leaving a gap of about 20 cm between the steel plate and the ground surface, and the range of the steel plate covering and protecting exceeds the boundary of the working area by at least 50 cm; The protective shed is assembled with steel pipe fasteners, and two layers of wire mesh are laid on the outside. The four corners of the protective shed are anchored to the counterweight pier with steel wire ropes. The steel pipe is set as the inner skeleton, and the mesh surface is a layer of high-strength steel rope diamond mesh and a layer of steel wire mesh with a pore size of 10mm.

7. The non-blasting excavation construction method for rocky stratum roadbed according to claim 1, characterized in that: In the step S5, a thermal expansion agent and an ignition tube are provided in the expansion tube, and the ignition tube lead extends to the outside of the expansion tube and is used to ignite the ignition tube in the expansion tube.

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