Secondary shaft completion construction method based on raise boring process

Abstract

A secondary shaft completion construction method includes drilling directional boring bit with directional boring machine, withdrawing directional boring rod and directional boring machine after directional boring hole construction is completed, measuring deviation of directional boring hole, installing raise boring machine, connecting small raise boring rod with reamer bit, carrying out secondary hole brushing by drilling reamer bit along directional boring hole to form pilot hole; replacing reamer bit by small raise boring bit, withdrawing small raise boring rod to drive small raise boring bit to excavate along the direction of pilot hole to form pilot shaft; withdrawing small raise boring rod and small raise boring bit, lowering large raise boring rod in pilot shaft from top to bottom along design direction of a vertical / inclined shaft, connecting large boring bit horizontally, and then driving and lifting boring bit by raise boring machine to excavate along pilot shaft to form shaft.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of excavation of a vertical shaft and an inclined shaft, and in particular to a secondary shaft completion construction method based on a raise boring process, which is suitable for pumped storage power stations, conventional hydropower stations or other underground shaft excavation projects.BACKGROUND OF THE INVENTION

[0002] At present, the vertical (inclined) shaft construction of a hydropower station mainly uses a manually operated borehole-blasting method. The borehole-blasting method not only generates a lot of noise and dust in the borehole-blasting process, but also cannot use mechanical danger elimination and slag removal due to the limited working space. The construction can only be carried out manually, and the manual operation efficiency is low, which cannot meet the requirement of the construction period. In addition, after blasting, it is easy to damage the surrounding rock structure and result in the risk of surrounding rock collapse. In addition, it is easy to result in safety accidents in the process of manual danger elimination and slag removal.

[0003] There are also vertical (inclined) shaft construction projects using the raise boring technology. However, most of the vertical shaft construction projects using the raise boring technology use a raise boring bit to excavate a pilot shaft to form a slag-removing shaft, and then use the slag-removing shaft formed by expanding excavation to carry out manual borehole-blasting and expanding excavation. Although the construction technology is simplified, the main amount of work is still manual expanding excavation, and there will also be risks of surrounding rock collapse.

[0004] There are also some projects that have applied the simultaneous shaft completion technology of the raise boring machine. The basic process is to directly expand the excavation from the pilot hole into a shaft at one time. Such method has extremely high requirements for the deviation rate of the pilot hole. The deviation rate of the pilot hole directly influences the forming quality of the vertical shaft. If the pilot hole is deviated, it is necessary to rectify the deviation. The methods of removing the rod, grouting and re-drilling are usually selected for rectifying the deviation of the pilot hole, which increases the amount of work. Moreover, the excessively deviated shaft cannot be lined, and manual blasting is needed to rectify the deviation in the secondary construction of the shaft. These conditions will seriously influence the construction efficiency, so that the application scope of simultaneous shaft completion technology is greatly limited.

[0005] CN104196442A discloses a method of construction of a vertical shaft or an inclined shaft using a raise boring machine. The raise boring machine is used to drill a pilot hole downward along the axis of the inclined shaft in the horizontal expanding excavation area of an upper bend section. After the pilot hole is formed, the boring bit in a lower bending section is replaced by an expanding excavation cutter, and then a slag-removing pilot shaft is formed by reverse pulling and expanding excavation from bottom to top. Although a combined construction method of a pilot hole and a raise boring machine is used, there is still the problem of the deviation of the pilot hole in the pilot hole construction process, which cannot solve the problem of deviation in the subsequent slag-removing pilot shaft construction process.

[0006] CN111441718A discloses a construction method of high-precision pilot shaft excavation for a long inclined shaft with a large cross-section and a steep slope, a system thereof and an application thereof. First, an upper flat tunnel and a lower flat tunnel are excavated using the borehole-blasting method, and the pilot holes are constructed in the upper flat tunnel and the lower flat tunnel, and then the pilot holes are brushed to be large. Thereafter, the raise boring machine is used for forward drilling and excavation, and finally the reamer bit is replaced at the lower part. The pilot shaft is formed by raise boring and expanding excavation. Although multi-drilling construction is also used, the first drilling of the raise boring machine is to carry out forward drilling directly based on the original pilot hole. The second drilling and the first drilling share the raise boring machine and the boring rod, which cannot really solve the problem that the pilot shaft is deviated to result in the subsequent vertical shaft forming deviation.SUMMARY OF THE INVENTION

[0007] In order to solve the above problem, the present disclosure provides a secondary shaft completion construction method based on a raise boring process. Such method carries out the secondary expanding excavation construction on the basis of the pilot shaft excavated by the raise boring machine for a first time, so that the influence of the deviation of the pilot hole on shaft completion is effectively eliminated, the need for manual blasting and deviation rectification after reaming in a traditional manner is avoided, the construction efficiency and the safety are improved, the automation degree of reaming construction is improved, and the occurrence of safety accidents is effectively prevented.

[0008] In order to achieve the above technical features, the purpose of the present invention is to: a secondary shaft completion construction method based on a raise boring process, comprising the following steps:

[0009] Step 1, carrying out construction of a directional boring hole:

[0010] excavating a tunnel in an underground rock body in advance, arranging and installing a directional boring machine on the ground corresponding to the tunnel, installing a composite boring rod and a directional boring bit on the directional boring machine, drilling into the stratum along a design direction of a vertical / inclined shaft and penetrating through the stratum, communicating with the tunnel to complete the construction of directional boring hole, and then withdrawing the composite boring rod;

[0011] Step 2, measuring a deviation of the directional boring hole:

[0012] measuring a maximum deviation distance δ between an axis of the directional boring hole and a designed central axis of a vertical / inclined shaft;

[0013] Step 3, carrying out construction of a pilot hole:

[0014] disassembling the directional boring machine, installing a raise boring machine, connecting a small raise boring rod with a reamer bit, carrying out secondary hole brushing by drilling the reamer bit from top to bottom along a directional boring hole to form a pilot hole, and ensuring that the small raise boring rod is not withdrawn;

[0015] Step 4, carrying out construction of a pilot shaft:

[0016] selecting a small raise boring bit with a radius of r, in which r>δ is ensured, disassembling the reamer bit, replacing the reamer bit and installing the small raise boring bit at an end of the small raise boring rod, withdrawing the small raise boring rod to drive the small raise boring bit to reversely excavate the stratum, and excavating along the direction of the pilot hole to form a pilot shaft;

[0017] Step 5, carrying out construction of the vertical / inclined shaft:disassembling the small raise boring bit and the small raise boring rod, lowering a large raise boring rod to the tunnel along the design direction of the vertical / inclined shaft, installing a large raise boring bit on the head of the large raise boring rod, withdrawing the large raise boring rod by the raise boring machine, driving the large raise boring bit to reversely excavate the stratum along the designed central axis of the vertical / inclined shaft, and forming the vertical / inclined shaft at one time according to a designed excavation line of a vertical / inclined shaft.

[0018] Preferably, before the directional boring machine is arranged and installed in Step 1, concrete is poured on the ground to form a foundation platform, the directional boring machine is then fixed on the foundation platform with foundation bolts, and then all the foundation bolts are completely covered with concrete.

[0019] Preferably, in Step 1, the composite boring rod comprises a plurality of directional boring rods and stable boring rods; in the drilling process, the directional boring rod is installed on the directional boring machine, the directional boring bit is installed on the head of the directional boring rod, a stable boring rod is then connected at a tail end of the directional boring bit to form the composite boring rod, and the directional boring machine is started to drive the composite boring rod to drill into the stratum from top to bottom.

[0020] Preferably, in the process that the composite boring rod continues to drill, when the length of the composite boring rod is insufficient, the corresponding directional boring rod and the stable boring rod are fixedly connected at a tail end of the composite boring rod to form a new composite boring rod, the stratum is continuously drilled from top to bottom, the directional boring rod and the stable boring rod are repeatedly and alternately connected until the directional boring hole communicated with the tunnel is obtained, the composite boring rod is withdrawn, and the directional boring machine is disassembled.

[0021] Preferably, in the process of downward drilling of the directional boring rod, a certain deviation occurs at a joint of the directional boring rods, the directional boring rod is subjected to bending stress deformation due to the pressure, and the deviation at the joint of the directional boring rods is superimposed with the bending stress deformation of the directional boring rod itself, so that the entire directional boring rod deviates from the designed central axis of the vertical / inclined shaft toward the directional boring hole going downward in a spiral manner.

[0022] Preferably, a diameter of the directional boring hole ensures the directional boring rod to move freely up and down therein, but the diameter is smaller than that of the small raise boring rod; a central axis of the directional boring hole is spiral, and there is a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft.

[0023] Preferably, in Step 4, the central axis of the pilot shaft basically coincides with the central axis of the pilot hole in a spiral manner, and there is also a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft, but the radius r of the pilot shaft is ensured to be larger than the deviation of the pilot hole, so that the large raise boring rod is lowered straight to the tunnel at the bottom along the designed central axis of the vertical / inclined shaft.

[0024] Preferably, a diameter of the large raise boring rod is larger than that of the small raise boring rod, and the large raise boring rod drives the large raise boring bit to reversely excavate the stratum from bottom to top.

[0025] Preferably, a diameter of the large raise boring bit is greater than 4 m, and the large raise boring bit is installed at an end of the large raise boring rod to excavate the stratum with the rise of the large raise boring rod to form the vertical / inclined shaft.

[0026] Preferably, the central axis of the vertical / inclined shaft basically coincides with the designed central axis of the vertical / inclined shaft, and the deviation rate is close to 0.

[0027] Preferably, in Step 3, the diameter of the reamer bit is between 250 mm and 600 mm.

[0028] Preferably, in Step 5, after the vertical / inclined shaft is formed, a set of single-hook lifting systems is equipped to take on the functions of lowering materials and workers, the wall is built with integral metal formworks, seamless steel pipes are placed into concrete, and the shaft wall is poured.

[0029] Preferably, the reaming process is a process of breaking a large number of rocks, the model of reamer bits and the arrangement form of rock-breaking hobs need to be determined according to stratum rock conditions, and corresponding drilling parameters are made to achieve the purpose of drilling with the highest efficiency.

[0030] Preferably, the diameter size of the large raise boring rod is selected to ensure that the large raise boring rod is not interfered by an inner wall of the pilot shaft in the lowering process inside the pilot shaft, so that the axis of the large raise boring rod coincides with the designed central axis of the vertical / inclined shaft.

[0031] The present disclosure has the following beneficial effects.

[0032] 1. By using the construction method according to the present disclosure, the pilot hole is first excavated by the directional boring machine and the pilot bit, then the pilot bit is replaced by a small raise boring bit, and the stratum is reversely excavated to form a pilot shaft. Finally, a large raise boring rod is placed in the pilot shaft to ensure that the axis of the large raise boring rod completely coincides with the designed central axis of the vertical / inclined shaft. Thereafter, a large raise boring bit is used to carry out secondary reverse excavation on the stratum to form a vertical shaft. On the one hand, the automation degree of the reaming construction is improved, “zero blasting” is achieved really, the construction efficiency is improved, and the occurrence of safety accidents is effectively prevented. On the other hand, the raise boring technology is used to expand excavation twice to form a vertical shaft, which can eliminate the influence of the pilot hole deviation on the vertical shaft to the maximum extent. This not only avoids the deviation rectification methods such as removing the rod, grouting and re-drilling in the directional boring process, but also solves the problem that manual blasting and deviation rectification is needed after the raise boring machine technology expands excavation to form a shaft at one time, and improves the construction efficiency.

[0033] 2. In the present disclosure, the precision of the constructed directional boring hole can be ensured as much as possible by matching the stable boring rod with the directional boring rod, and the deviation between the constructed directional boring hole and the designed central axis of the vertical / inclined shaft can be reduced as much as possible.

[0034] 3. Aiming at the deviation problem, the present disclosure uses the subsequent process of the pilot hole, the pilot shaft and the secondary raise boring construction to overcome the influence of initial deviation, thus ensuring that the vertical / inclined shaft is formed at one time finally.

[0035] 4. In the present disclosure, in the present disclosure, the sizes of the radius r and the maximum deviation distance δ are selected, thus ensuring that the formed pilot shaft can travel along the designed central axis of the vertical / inclined shaft, so that the size of the pilot shaft can cover the designed central axis of the vertical / inclined shaft. Further, the designed central axis of the vertical / inclined shaft is exposed, providing a construction basis for the subsequent secondary reverse excavation.BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present disclosure will be further explained with reference to the accompanying drawings and embodiments.

[0037] FIG. 1 is a flow chart of construction of the present disclosure.

[0038] FIG. 2 is a schematic diagram of construction of a directional boring hole according to the present disclosure.

[0039] FIG. 3 is a partial enlarged view of part A in FIG. 2.

[0040] FIG. 4 is a schematic diagram of construction of a pilot hole according to the present disclosure.

[0041] FIG. 5 is an enlarged view of part B in FIG. 4 according to the present disclosure.

[0042] FIG. 6 is a schematic diagram of construction of a pilot shaft according to the present disclosure.

[0043] FIG. 7 is a partial enlarged view of part C in FIG. 6.

[0044] FIG. 8 is a schematic diagram of construction of a vertical / inclined shaft according to the present disclosure.

[0045] In the figures: 1—tunnel, 2—foundation platform, 3—directional boring machine, 4—directional boring bit, 5—composite boring rod,6—designed central axis of a vertical / inclined shaft, 7—designed excavation line of a vertical / inclined shaft, 8—directional boring hole, 9—raise boring machine, 10—small raise boring rod, 11—reamer bit, 12—pilot hole; 13—small raise boring bit; 14—pilot shaft; 15—large raise boring rod; 16—large raise boring bit; 17—vertical / inclined shaftDETAILED DESCRIPTION OF THE EMBODIMENTS

[0046] The embodiments of the present disclosure will be further described with reference to the accompanying drawings hereinafter.Embodiment 1

[0047] Referring to FIG. 1 to FIG. 8, a secondary shaft completion construction method based on a raise boring process includes the following steps.

[0048] Step 1, construction of a directional boring hole 8 is carried out.

[0049] A tunnel 1 is excavated in an underground rock body in advance. A directional boring machine 3 is arranged and installed on the ground corresponding to the tunnel 1. A composite boring rod 5 and a directional boring bit 4 are installed on the directional boring machine 3, drilling into the stratum along a design direction of a vertical / inclined shaft and penetrating through the stratum, communicating with the tunnel 1 to complete the construction of directional boring hole 8. The composite boring rod 5 is then withdrawn.

[0050] Further preferably, in order to ensure the installation stability of the directional boring machine 3 and the subsequent normal drilling construction, before the directional boring machine 3 is arranged and installed, concrete is poured on the ground to form a foundation platform 2. The directional boring machine 3 is then fixed on the foundation platform 2 with foundation bolts, and then all the foundation bolts are completely covered with concrete. Through the above structure, the reliability of fixing the directional boring machine 3 is ensured.

[0051] Further preferably, due to the relatively complex rock structure of the stratum, the directional boring bit 4 will inevitably have deviation in the drilling process. In order to reduce the drilling deviation of the directional boring hole bit 4 as much as possible, the composite boring rod 5 includes a plurality of directional boring rods and stable boring rods. In the drilling process, the directional boring rod is installed on the directional boring machine 3. The directional boring bit 4 is installed on the head of the directional boring rod. A stable boring rod is then connected at a tail end of the directional boring bit 4 to form the composite boring rod 5, and the directional boring machine 3 is started to drive the composite boring rod 5 to drill into the stratum from top to bottom. Furthermore, the precision of the constructed directional boring hole 8 can be ensured as much as possible by matching the stable boring rod with the directional boring rod, and the deviation between the constructed directional boring hole and the designed central axis of the vertical / inclined shaft 6 can be reduced as much as possible.

[0052] Further preferably, in the process that the composite boring rod 5 continues to drill, when the length of the composite boring rod 5 is insufficient, the corresponding directional boring rod and the stable boring rod are fixedly connected at a tail end of the composite boring rod 5 to form a new composite boring rod. The stratum is continuously drilled from top to bottom. The directional boring rod and the stable boring rod are repeatedly and alternately connected until the directional boring hole 8 communicated with the tunnel 1 is obtained. The composite boring rod 5 is withdrawn, and the directional boring machine 3 is disassembled. Through the extension of the composite boring rod 5, large-length vertical / inclined shaft construction can be achieved, effectively enhancing its adaptability.

[0053] Further preferably, in the process of downward drilling of the directional boring rod, a certain deviation occurs at a joint of the directional boring rods. The directional boring rod is subjected to bending stress deformation due to the pressure. The deviation at the joint of the directional boring rods is superimposed with the bending stress deformation of the directional boring rod itself, so that the entire directional boring rod deviates from the designed central axis of the vertical / inclined shaft 6 toward the directional boring hole 8 going downward in a spiral manner. Just because the deviation of the directional boring hole 8 cannot be avoided or overcome fundamentally, traditional construction methods are used, so that the subsequent formed vertical / inclined shaft has deviation, which cannot meet the design requirements and result in the problem of abandoned holes. Based on this, in the present disclosure, in view of the deviation problem, the subsequent process of the pilot hole, the pilot shaft and the secondary raise boring construction is used to overcome the influence of initial deviation, and then the vertical / inclined shaft 17 is formed at one time finally.

[0054] Step 2, a deviation of the directional boring hole 8 is measured.

[0055] A maximum deviation distance δ between an axis of the directional boring hole 8 and a designed central axis of a vertical / inclined shaft 6 is measured.

[0056] The deviation distance δ is an unavoidable deviation of the directional boring hole 8. It will take a lot of time and economic cost to control the deviation distance δ to be small. However, as long as a small raise boring bit with the radius r>δ is selected and the secondary raise boring construction is carried out to complete the shaft, the influence resulted from the deviation of the directional boring hole can be avoided.

[0057] Further preferably, a diameter of the directional boring hole 8 ensures the directional boring rod to move freely up and down therein, but the diameter is smaller than that of the small raise boring rod 10; a central axis of the directional boring hole 8 is spiral, and there is a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft 6.

[0058] The deviation distance δ of the directional boring hole 8 is measured mainly to facilitate the subsequent selection of the size of the small raise boring bit 13, so as to ensure that the pilot hole 12 can be formed at one time through the small raise boring bit 13 in the subsequent construction process of using the small raise boring bit 13, so as to complete the exposure of the designed central axis of the vertical / inclined shaft 6 and facilitate the subsequent arrangement and installation of the small raise boring rod 10.

[0059] Step 3, construction of a pilot hole 12 is carried out.

[0060] The directional boring machine 3 is disassembled, and a raise boring machine 9 is installed. A small raise boring rod 10 is connected with a reamer bit 11. Secondary hole brushing is carried out by drilling the reamer bit 11 from top to bottom along a directional boring hole 8 to form a pilot hole 12, and it is ensured that the small raise boring rod 10 is not withdrawn.

[0061] Because the pilot hole 12 is mainly drilled with reference to the direction of the directional boring hole 8, a spiral shape will be inevitably formed in the drilling process of the pilot hole 12, and then there will be a certain deviation. However, the pilot hole 12 mainly provides the foundation for the subsequent construction of the pilot hole 14. Although the pilot hole is consistent with the directional boring hole 8, there is still deviation, which will not influence the subsequent raise boring construction process. Based on this, the deviation here does not need to be treated additionally in the specific construction process.

[0062] Step 4, construction of a pilot shaft 14 is carried out.

[0063] A small raise boring bit 13 with a radius of r is selected, in which r>δ is ensured. The reamer bit 11 is disassembled, the reamer bit is replaced, and the small raise boring bit 13 is installed at an end of the small raise boring rod 10. The small raise boring rod 10 is withdrawn to drive the small raise boring bit 13 to reversely excavate the stratum, excavating along the direction of the pilot hole 12 to form a pilot shaft 14.

[0064] Further preferably, in Step 4, the central axis of the pilot shaft 14 basically coincides with the central axis of the pilot hole 12 in a spiral manner. There is also a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft, but the radius r of the pilot shaft 14 is ensured to be larger than the deviation of the pilot hole 12, so that the large raise boring rod 15 is lowered straight to the tunnel 1 at the bottom along the designed central axis of the vertical / inclined shaft 6.

[0065] Based on this, in the present disclosure, the sizes of the radius r and the maximum deviation distance δ are selected, thus ensuring that the formed pilot shaft 14 can travel along the designed central axis of the vertical / inclined shaft 6, so that the size of the pilot shaft 14 can cover the designed central axis of the vertical / inclined shaft 6. Further, the designed central axis of the vertical / inclined shaft 6 is exposed, providing a construction basis for the subsequent secondary reverse excavation.

[0066] Step 5, construction of the vertical / inclined shaft 17 is carried out.

[0067] The small raise boring bit 13 and the small raise boring rod 10 are disassembled. A large raise boring rod 15 is lowered to the tunnel 1 along the design direction of the vertical / inclined shaft. A large raise boring bit 16 is installed on the head of the large raise boring rod 15. The large raise boring rod 15 is withdrawn by the raise boring machine 9, driving the large raise boring bit 16 to reversely excavate the stratum along the designed central axis of the vertical / inclined shaft 6, and forming the vertical / inclined shaft 17 at one time according to a designed excavation line of a vertical / inclined shaft 7.

[0068] Further preferably, a diameter of the large raise boring rod 15 is larger than that of the small raise boring rod 10, and the large raise boring rod drives the large raise boring bit 16 to reversely excavate the stratum from bottom to top.

[0069] Further preferably, a diameter of the large raise boring bit 16 is greater than 4 m, and the large raise boring bit is installed at an end of the large raise boring rod 15 to excavate the stratum with the rise of the large raise boring rod 15 to form the vertical / inclined shaft 17.

[0070] Further preferably, the central axis of the vertical / inclined shaft 17 basically coincides with the designed central axis of the vertical / inclined shaft 6, and the deviation rate is close to 0.

[0071] Further preferably, in Step 3, the diameter of the reamer bit 11 is between 250 mm and 600 mm.

[0072] Further preferably, in Step 5, after the vertical / inclined shaft 17 is formed, a set of single-hook lifting systems is equipped to take on the functions of lowering materials and workers, the wall is built with integral metal formworks, seamless steel pipes are placed into concrete, and the shaft wall is poured. The above arrangement can be used to effectively support the vertical / inclined shaft 17 after being formed.

[0073] Further preferably, the reaming process is a process of breaking a large number of rocks. The model of reamer bits and the arrangement form of rock-breaking hobs need to be determined according to stratum rock conditions. Corresponding drilling parameters are made to achieve the purpose of drilling with the highest efficiency. The above bit selection enhances the adaptability, so as to ensure the adaptability to different rock strata.

[0074] Further preferably, the diameter size of the large raise boring rod 15 is selected to ensure that the large raise boring rod is not interfered by an inner wall of the pilot shaft 14 in the lowering process inside the pilot shaft 14, so that the axis of the large raise boring rod 15 coincides with the designed central axis of the vertical / inclined shaft 6. The above size selection ensures that the formed vertical / inclined shaft 17 is a shaft that just meets the designed central axis 6 of the vertical / inclined shaft in the final raise boring construction process, which ensures the forming accuracy and effectively overcomes the deviation influence of the original directional boring hole 8.Embodiment 2

[0075] The present disclosure provides a secondary shaft completion construction method based on a raise boring process. The present disclosure uses the following technical scheme. In the scheme, the boring direction of trepanning the directional boring hole and reaming the pilot hole is the forward boring direction, and the reamer boring direction of the small raise boring bit 13 and the large raise boring bit 16 is the raise boring direction. This embodiment takes the vertical shaft drilling construction of a raise boring machine as an example, and the steps are as follows.

[0076] S1: preparation is carried out before construction. A tunnel 1 is excavated in an underground rock body in advance. Prior to the process that the directional boring machine 3 is arranged on the ground corresponding to the tunnel, concrete is poured on the ground to form a foundation platform 2. The directional boring machine 3 is then fixed on the foundation platform 2 with foundation bolts, and then all the foundation bolts are completely covered with concrete.

[0077] S2: according to the use requirements of the directional boring machine 3, the directional boring machine 3 is arranged on the ground corresponding to the tunnel 1, and a directional boring bit 4 of φ195 mm, a plurality of stable boring rods and a directional boring rod are provided.

[0078] S3: the directional boring bit 4 is installed on the directional boring machine 3. A stable boring rod is then connected at a tail end of the directional boring bit to form the composite boring rod 5, and the directional boring machine is started to drive the composite boring rod 5 to drill into the stratum from top to bottom.

[0079] S4: a directional boring rod is fixedly connected at a tail end of the composite boring rod to form a new composite boring rod 5. The stratum is continuously drilled from top to bottom.

[0080] S5: S4 is carried out repeatedly. The directional boring rod and the stable boring rod are alternately connected until the directional boring hole 8 communicated with the tunnel is obtained. The composite boring rod is withdrawn, and the directional boring machine is disassembled.

[0081] S6: a maximum deviation δ between the central axis of the directional boring hole and the designed central axis of the vertical shaft is measured using a measuring instrument to be 0.7 m. the radius r of the small raise boring bit 13 is selected to be 1 m, which is more than 0.7 m.

[0082] S7: the raise boring machine 9 is installed according to the use requirements of the raise boring machine. The small raise boring rod 10, the φ350 mm reamer bit 11, the φ2 m small raise boring bit 13, the large raise boring rod 15 and the φ7 m large raise boring bit 16 are provided.

[0083] S8: the reamer bit 11 is installed at an end of the small raise boring rod 10. The small raise boring rod and the reamer bit are driven by the raise boring machine 9 to drill into the stratum from top to bottom along the directional boring hole to reach the tunnel, so as to form a pilot hole 12.

[0084] S9: the reamer bit 11 is disassembled, and the small raise boring bit 13 is assembled at the end of the small raise boring rod.

[0085] S10: the small raise boring bit 13 is withdrawn along the pilot hole 12 to drive the small raise boring bit 13 to reversely excavate the stratum to form a pilot shaft 14, wherein the pilot hole has a radius of 1 m. A maximum deviation between the central axis of the pilot shaft and the designed central axis of the vertical shaft is 0.7 m, which is smaller than the radius of the pilot hole and meets the secondary drilling requirement.

[0086] S11: the large raise boring rod 15 is lowered straight to the tunnel 1 along the designed central axis of the vertical shaft, and the large raise boring bit 16 is installed at the end of the large raise boring rod 15.

[0087] S12: the large raise boring rod 15 is withdrawn to drive the large raise boring bit 16 with a large size to excavate the stratum from bottom to top along the design direction of the vertical shaft to form the vertical shaft. The boundary line of the vertical shaft basically coincides with the boundary line of the designed vertical shaft.

[0088] S13: after the secondary expanding excavation of the raise boring machine forms a shaft, a set of single-hook lifting systems is equipped to take on the functions of lowering materials and workers. The wall is built with integral metal formworks. Seamless steel pipes are placed into concrete, and the shaft wall is poured.

Examples

embodiment 1

[0047]Referring to FIG. 1 to FIG. 8, a secondary shaft completion construction method based on a raise boring process includes the following steps.[0048]Step 1, construction of a directional boring hole 8 is carried out.

[0049]A tunnel 1 is excavated in an underground rock body in advance. A directional boring machine 3 is arranged and installed on the ground corresponding to the tunnel 1. A composite boring rod 5 and a directional boring bit 4 are installed on the directional boring machine 3, drilling into the stratum along a design direction of a vertical / inclined shaft and penetrating through the stratum, communicating with the tunnel 1 to complete the construction of directional boring hole 8. The composite boring rod 5 is then withdrawn.

[0050]Further preferably, in order to ensure the installation stability of the directional boring machine 3 and the subsequent normal drilling construction, before the directional boring machine 3 is arranged and installed, concrete is poured on...

embodiment 2

[0075]The present disclosure provides a secondary shaft completion construction method based on a raise boring process. The present disclosure uses the following technical scheme. In the scheme, the boring direction of trepanning the directional boring hole and reaming the pilot hole is the forward boring direction, and the reamer boring direction of the small raise boring bit 13 and the large raise boring bit 16 is the raise boring direction. This embodiment takes the vertical shaft drilling construction of a raise boring machine as an example, and the steps are as follows.[0076]S1: preparation is carried out before construction. A tunnel 1 is excavated in an underground rock body in advance. Prior to the process that the directional boring machine 3 is arranged on the ground corresponding to the tunnel, concrete is poured on the ground to form a foundation platform 2. The directional boring machine 3 is then fixed on the foundation platform 2 with foundation bolts, and then all th...

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of excavation of a vertical shaft and an inclined shaft, and in particular to a secondary shaft completion construction method based on a raise boring process, which is suitable for pumped storage power stations, conventional hydropower stations or other underground shaft excavation projects.BACKGROUND OF THE INVENTION

[0002] At present, the vertical (inclined) shaft construction of a hydropower station mainly uses a manually operated borehole-blasting method. The borehole-blasting method not only generates a lot of noise and dust in the borehole-blasting process, but also cannot use mechanical danger elimination and slag removal due to the limited working space. The construction can only be carried out manually, and the manual operation efficiency is low, which cannot meet the requirement of the construction period. In addition, after blasting, it is easy to damage the surrounding rock structure and result in the risk of surrounding rock collapse. In addition, it is easy to result in safety accidents in the process of manual danger elimination and slag removal.

[0003] There are also vertical (inclined) shaft construction projects using the raise boring technology. However, most of the vertical shaft construction projects using the raise boring technology use a raise boring bit to excavate a pilot shaft to form a slag-removing shaft, and then use the slag-removing shaft formed by expanding excavation to carry out manual borehole-blasting and expanding excavation. Although the construction technology is simplified, the main amount of work is still manual expanding excavation, and there will also be risks of surrounding rock collapse.

[0004] There are also some projects that have applied the simultaneous shaft completion technology of the raise boring machine. The basic process is to directly expand the excavation from the pilot hole into a shaft at one time. Such method has extremely high requirements for the deviation rate of the pilot hole. The deviation rate of the pilot hole directly influences the forming quality of the vertical shaft. If the pilot hole is deviated, it is necessary to rectify the deviation. The methods of removing the rod, grouting and re-drilling are usually selected for rectifying the deviation of the pilot hole, which increases the amount of work. Moreover, the excessively deviated shaft cannot be lined, and manual blasting is needed to rectify the deviation in the secondary construction of the shaft. These conditions will seriously influence the construction efficiency, so that the application scope of simultaneous shaft completion technology is greatly limited.

[0005] CN104196442A discloses a method of construction of a vertical shaft or an inclined shaft using a raise boring machine. The raise boring machine is used to drill a pilot hole downward along the axis of the inclined shaft in the horizontal expanding excavation area of an upper bend section. After the pilot hole is formed, the boring bit in a lower bending section is replaced by an expanding excavation cutter, and then a slag-removing pilot shaft is formed by reverse pulling and expanding excavation from bottom to top. Although a combined construction method of a pilot hole and a raise boring machine is used, there is still the problem of the deviation of the pilot hole in the pilot hole construction process, which cannot solve the problem of deviation in the subsequent slag-removing pilot shaft construction process.

[0006] CN111441718A discloses a construction method of high-precision pilot shaft excavation for a long inclined shaft with a large cross-section and a steep slope, a system thereof and an application thereof. First, an upper flat tunnel and a lower flat tunnel are excavated using the borehole-blasting method, and the pilot holes are constructed in the upper flat tunnel and the lower flat tunnel, and then the pilot holes are brushed to be large. Thereafter, the raise boring machine is used for forward drilling and excavation, and finally the reamer bit is replaced at the lower part. The pilot shaft is formed by raise boring and expanding excavation. Although multi-drilling construction is also used, the first drilling of the raise boring machine is to carry out forward drilling directly based on the original pilot hole. The second drilling and the first drilling share the raise boring machine and the boring rod, which cannot really solve the problem that the pilot shaft is deviated to result in the subsequent vertical shaft forming deviation.SUMMARY OF THE INVENTION

[0007] In order to solve the above problem, the present disclosure provides a secondary shaft completion construction method based on a raise boring process. Such method carries out the secondary expanding excavation construction on the basis of the pilot shaft excavated by the raise boring machine for a first time, so that the influence of the deviation of the pilot hole on shaft completion is effectively eliminated, the need for manual blasting and deviation rectification after reaming in a traditional manner is avoided, the construction efficiency and the safety are improved, the automation degree of reaming construction is improved, and the occurrence of safety accidents is effectively prevented.

[0008] In order to achieve the above technical features, the purpose of the present invention is to: a secondary shaft completion construction method based on a raise boring process, comprising the following steps:

[0009] Step 1, carrying out construction of a directional boring hole:

[0010] excavating a tunnel in an underground rock body in advance, arranging and installing a directional boring machine on the ground corresponding to the tunnel, installing a composite boring rod and a directional boring bit on the directional boring machine, drilling into the stratum along a design direction of a vertical / inclined shaft and penetrating through the stratum, communicating with the tunnel to complete the construction of directional boring hole, and then withdrawing the composite boring rod;

[0011] Step 2, measuring a deviation of the directional boring hole:

[0012] measuring a maximum deviation distance δ between an axis of the directional boring hole and a designed central axis of a vertical / inclined shaft;

[0013] Step 3, carrying out construction of a pilot hole:

[0014] disassembling the directional boring machine, installing a raise boring machine, connecting a small raise boring rod with a reamer bit, carrying out secondary hole brushing by drilling the reamer bit from top to bottom along a directional boring hole to form a pilot hole, and ensuring that the small raise boring rod is not withdrawn;

[0015] Step 4, carrying out construction of a pilot shaft:

[0016] selecting a small raise boring bit with a radius of r, in which r>δ is ensured, disassembling the reamer bit, replacing the reamer bit and installing the small raise boring bit at an end of the small raise boring rod, withdrawing the small raise boring rod to drive the small raise boring bit to reversely excavate the stratum, and excavating along the direction of the pilot hole to form a pilot shaft;

[0017] Step 5, carrying out construction of the vertical / inclined shaft:disassembling the small raise boring bit and the small raise boring rod, lowering a large raise boring rod to the tunnel along the design direction of the vertical / inclined shaft, installing a large raise boring bit on the head of the large raise boring rod, withdrawing the large raise boring rod by the raise boring machine, driving the large raise boring bit to reversely excavate the stratum along the designed central axis of the vertical / inclined shaft, and forming the vertical / inclined shaft at one time according to a designed excavation line of a vertical / inclined shaft.

[0018] Preferably, before the directional boring machine is arranged and installed in Step 1, concrete is poured on the ground to form a foundation platform, the directional boring machine is then fixed on the foundation platform with foundation bolts, and then all the foundation bolts are completely covered with concrete.

[0019] Preferably, in Step 1, the composite boring rod comprises a plurality of directional boring rods and stable boring rods; in the drilling process, the directional boring rod is installed on the directional boring machine, the directional boring bit is installed on the head of the directional boring rod, a stable boring rod is then connected at a tail end of the directional boring bit to form the composite boring rod, and the directional boring machine is started to drive the composite boring rod to drill into the stratum from top to bottom.

[0020] Preferably, in the process that the composite boring rod continues to drill, when the length of the composite boring rod is insufficient, the corresponding directional boring rod and the stable boring rod are fixedly connected at a tail end of the composite boring rod to form a new composite boring rod, the stratum is continuously drilled from top to bottom, the directional boring rod and the stable boring rod are repeatedly and alternately connected until the directional boring hole communicated with the tunnel is obtained, the composite boring rod is withdrawn, and the directional boring machine is disassembled.

[0021] Preferably, in the process of downward drilling of the directional boring rod, a certain deviation occurs at a joint of the directional boring rods, the directional boring rod is subjected to bending stress deformation due to the pressure, and the deviation at the joint of the directional boring rods is superimposed with the bending stress deformation of the directional boring rod itself, so that the entire directional boring rod deviates from the designed central axis of the vertical / inclined shaft toward the directional boring hole going downward in a spiral manner.

[0022] Preferably, a diameter of the directional boring hole ensures the directional boring rod to move freely up and down therein, but the diameter is smaller than that of the small raise boring rod; a central axis of the directional boring hole is spiral, and there is a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft.

[0023] Preferably, in Step 4, the central axis of the pilot shaft basically coincides with the central axis of the pilot hole in a spiral manner, and there is also a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft, but the radius r of the pilot shaft is ensured to be larger than the deviation of the pilot hole, so that the large raise boring rod is lowered straight to the tunnel at the bottom along the designed central axis of the vertical / inclined shaft.

[0024] Preferably, a diameter of the large raise boring rod is larger than that of the small raise boring rod, and the large raise boring rod drives the large raise boring bit to reversely excavate the stratum from bottom to top.

[0025] Preferably, a diameter of the large raise boring bit is greater than 4 m, and the large raise boring bit is installed at an end of the large raise boring rod to excavate the stratum with the rise of the large raise boring rod to form the vertical / inclined shaft.

[0026] Preferably, the central axis of the vertical / inclined shaft basically coincides with the designed central axis of the vertical / inclined shaft, and the deviation rate is close to 0.

[0027] Preferably, in Step 3, the diameter of the reamer bit is between 250 mm and 600 mm.

[0028] Preferably, in Step 5, after the vertical / inclined shaft is formed, a set of single-hook lifting systems is equipped to take on the functions of lowering materials and workers, the wall is built with integral metal formworks, seamless steel pipes are placed into concrete, and the shaft wall is poured.

[0029] Preferably, the reaming process is a process of breaking a large number of rocks, the model of reamer bits and the arrangement form of rock-breaking hobs need to be determined according to stratum rock conditions, and corresponding drilling parameters are made to achieve the purpose of drilling with the highest efficiency.

[0030] Preferably, the diameter size of the large raise boring rod is selected to ensure that the large raise boring rod is not interfered by an inner wall of the pilot shaft in the lowering process inside the pilot shaft, so that the axis of the large raise boring rod coincides with the designed central axis of the vertical / inclined shaft.

[0031] The present disclosure has the following beneficial effects.

[0032] 1. By using the construction method according to the present disclosure, the pilot hole is first excavated by the directional boring machine and the pilot bit, then the pilot bit is replaced by a small raise boring bit, and the stratum is reversely excavated to form a pilot shaft. Finally, a large raise boring rod is placed in the pilot shaft to ensure that the axis of the large raise boring rod completely coincides with the designed central axis of the vertical / inclined shaft. Thereafter, a large raise boring bit is used to carry out secondary reverse excavation on the stratum to form a vertical shaft. On the one hand, the automation degree of the reaming construction is improved, “zero blasting” is achieved really, the construction efficiency is improved, and the occurrence of safety accidents is effectively prevented. On the other hand, the raise boring technology is used to expand excavation twice to form a vertical shaft, which can eliminate the influence of the pilot hole deviation on the vertical shaft to the maximum extent. This not only avoids the deviation rectification methods such as removing the rod, grouting and re-drilling in the directional boring process, but also solves the problem that manual blasting and deviation rectification is needed after the raise boring machine technology expands excavation to form a shaft at one time, and improves the construction efficiency.

[0033] 2. In the present disclosure, the precision of the constructed directional boring hole can be ensured as much as possible by matching the stable boring rod with the directional boring rod, and the deviation between the constructed directional boring hole and the designed central axis of the vertical / inclined shaft can be reduced as much as possible.

[0034] 3. Aiming at the deviation problem, the present disclosure uses the subsequent process of the pilot hole, the pilot shaft and the secondary raise boring construction to overcome the influence of initial deviation, thus ensuring that the vertical / inclined shaft is formed at one time finally.

[0035] 4. In the present disclosure, in the present disclosure, the sizes of the radius r and the maximum deviation distance δ are selected, thus ensuring that the formed pilot shaft can travel along the designed central axis of the vertical / inclined shaft, so that the size of the pilot shaft can cover the designed central axis of the vertical / inclined shaft. Further, the designed central axis of the vertical / inclined shaft is exposed, providing a construction basis for the subsequent secondary reverse excavation.BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present disclosure will be further explained with reference to the accompanying drawings and embodiments.

[0037] FIG. 1 is a flow chart of construction of the present disclosure.

[0038] FIG. 2 is a schematic diagram of construction of a directional boring hole according to the present disclosure.

[0039] FIG. 3 is a partial enlarged view of part A in FIG. 2.

[0040] FIG. 4 is a schematic diagram of construction of a pilot hole according to the present disclosure.

[0041] FIG. 5 is an enlarged view of part B in FIG. 4 according to the present disclosure.

[0042] FIG. 6 is a schematic diagram of construction of a pilot shaft according to the present disclosure.

[0043] FIG. 7 is a partial enlarged view of part C in FIG. 6.

[0044] FIG. 8 is a schematic diagram of construction of a vertical / inclined shaft according to the present disclosure.

[0045] In the figures: 1—tunnel, 2—foundation platform, 3—directional boring machine, 4—directional boring bit, 5—composite boring rod,6—designed central axis of a vertical / inclined shaft, 7—designed excavation line of a vertical / inclined shaft, 8—directional boring hole, 9—raise boring machine, 10—small raise boring rod, 11—reamer bit, 12—pilot hole; 13—small raise boring bit; 14—pilot shaft; 15—large raise boring rod; 16—large raise boring bit; 17—vertical / inclined shaftDETAILED DESCRIPTION OF THE EMBODIMENTS

[0046] The embodiments of the present disclosure will be further described with reference to the accompanying drawings hereinafter.Embodiment 1

[0047] Referring to FIG. 1 to FIG. 8, a secondary shaft completion construction method based on a raise boring process includes the following steps.

[0048] Step 1, construction of a directional boring hole 8 is carried out.

[0049] A tunnel 1 is excavated in an underground rock body in advance. A directional boring machine 3 is arranged and installed on the ground corresponding to the tunnel 1. A composite boring rod 5 and a directional boring bit 4 are installed on the directional boring machine 3, drilling into the stratum along a design direction of a vertical / inclined shaft and penetrating through the stratum, communicating with the tunnel 1 to complete the construction of directional boring hole 8. The composite boring rod 5 is then withdrawn.

[0050] Further preferably, in order to ensure the installation stability of the directional boring machine 3 and the subsequent normal drilling construction, before the directional boring machine 3 is arranged and installed, concrete is poured on the ground to form a foundation platform 2. The directional boring machine 3 is then fixed on the foundation platform 2 with foundation bolts, and then all the foundation bolts are completely covered with concrete. Through the above structure, the reliability of fixing the directional boring machine 3 is ensured.

[0051] Further preferably, due to the relatively complex rock structure of the stratum, the directional boring bit 4 will inevitably have deviation in the drilling process. In order to reduce the drilling deviation of the directional boring hole bit 4 as much as possible, the composite boring rod 5 includes a plurality of directional boring rods and stable boring rods. In the drilling process, the directional boring rod is installed on the directional boring machine 3. The directional boring bit 4 is installed on the head of the directional boring rod. A stable boring rod is then connected at a tail end of the directional boring bit 4 to form the composite boring rod 5, and the directional boring machine 3 is started to drive the composite boring rod 5 to drill into the stratum from top to bottom. Furthermore, the precision of the constructed directional boring hole 8 can be ensured as much as possible by matching the stable boring rod with the directional boring rod, and the deviation between the constructed directional boring hole and the designed central axis of the vertical / inclined shaft 6 can be reduced as much as possible.

[0052] Further preferably, in the process that the composite boring rod 5 continues to drill, when the length of the composite boring rod 5 is insufficient, the corresponding directional boring rod and the stable boring rod are fixedly connected at a tail end of the composite boring rod 5 to form a new composite boring rod. The stratum is continuously drilled from top to bottom. The directional boring rod and the stable boring rod are repeatedly and alternately connected until the directional boring hole 8 communicated with the tunnel 1 is obtained. The composite boring rod 5 is withdrawn, and the directional boring machine 3 is disassembled. Through the extension of the composite boring rod 5, large-length vertical / inclined shaft construction can be achieved, effectively enhancing its adaptability.

[0053] Further preferably, in the process of downward drilling of the directional boring rod, a certain deviation occurs at a joint of the directional boring rods. The directional boring rod is subjected to bending stress deformation due to the pressure. The deviation at the joint of the directional boring rods is superimposed with the bending stress deformation of the directional boring rod itself, so that the entire directional boring rod deviates from the designed central axis of the vertical / inclined shaft 6 toward the directional boring hole 8 going downward in a spiral manner. Just because the deviation of the directional boring hole 8 cannot be avoided or overcome fundamentally, traditional construction methods are used, so that the subsequent formed vertical / inclined shaft has deviation, which cannot meet the design requirements and result in the problem of abandoned holes. Based on this, in the present disclosure, in view of the deviation problem, the subsequent process of the pilot hole, the pilot shaft and the secondary raise boring construction is used to overcome the influence of initial deviation, and then the vertical / inclined shaft 17 is formed at one time finally.

[0054] Step 2, a deviation of the directional boring hole 8 is measured.

[0055] A maximum deviation distance δ between an axis of the directional boring hole 8 and a designed central axis of a vertical / inclined shaft 6 is measured.

[0056] The deviation distance δ is an unavoidable deviation of the directional boring hole 8. It will take a lot of time and economic cost to control the deviation distance δ to be small. However, as long as a small raise boring bit with the radius r>δ is selected and the secondary raise boring construction is carried out to complete the shaft, the influence resulted from the deviation of the directional boring hole can be avoided.

[0057] Further preferably, a diameter of the directional boring hole 8 ensures the directional boring rod to move freely up and down therein, but the diameter is smaller than that of the small raise boring rod 10; a central axis of the directional boring hole 8 is spiral, and there is a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft 6.

[0058] The deviation distance δ of the directional boring hole 8 is measured mainly to facilitate the subsequent selection of the size of the small raise boring bit 13, so as to ensure that the pilot hole 12 can be formed at one time through the small raise boring bit 13 in the subsequent construction process of using the small raise boring bit 13, so as to complete the exposure of the designed central axis of the vertical / inclined shaft 6 and facilitate the subsequent arrangement and installation of the small raise boring rod 10.

[0059] Step 3, construction of a pilot hole 12 is carried out.

[0060] The directional boring machine 3 is disassembled, and a raise boring machine 9 is installed. A small raise boring rod 10 is connected with a reamer bit 11. Secondary hole brushing is carried out by drilling the reamer bit 11 from top to bottom along a directional boring hole 8 to form a pilot hole 12, and it is ensured that the small raise boring rod 10 is not withdrawn.

[0061] Because the pilot hole 12 is mainly drilled with reference to the direction of the directional boring hole 8, a spiral shape will be inevitably formed in the drilling process of the pilot hole 12, and then there will be a certain deviation. However, the pilot hole 12 mainly provides the foundation for the subsequent construction of the pilot hole 14. Although the pilot hole is consistent with the directional boring hole 8, there is still deviation, which will not influence the subsequent raise boring construction process. Based on this, the deviation here does not need to be treated additionally in the specific construction process.

[0062] Step 4, construction of a pilot shaft 14 is carried out.

[0063] A small raise boring bit 13 with a radius of r is selected, in which r>δ is ensured. The reamer bit 11 is disassembled, the reamer bit is replaced, and the small raise boring bit 13 is installed at an end of the small raise boring rod 10. The small raise boring rod 10 is withdrawn to drive the small raise boring bit 13 to reversely excavate the stratum, excavating along the direction of the pilot hole 12 to form a pilot shaft 14.

[0064] Further preferably, in Step 4, the central axis of the pilot shaft 14 basically coincides with the central axis of the pilot hole 12 in a spiral manner. There is also a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft, but the radius r of the pilot shaft 14 is ensured to be larger than the deviation of the pilot hole 12, so that the large raise boring rod 15 is lowered straight to the tunnel 1 at the bottom along the designed central axis of the vertical / inclined shaft 6.

[0065] Based on this, in the present disclosure, the sizes of the radius r and the maximum deviation distance δ are selected, thus ensuring that the formed pilot shaft 14 can travel along the designed central axis of the vertical / inclined shaft 6, so that the size of the pilot shaft 14 can cover the designed central axis of the vertical / inclined shaft 6. Further, the designed central axis of the vertical / inclined shaft 6 is exposed, providing a construction basis for the subsequent secondary reverse excavation.

[0066] Step 5, construction of the vertical / inclined shaft 17 is carried out.

[0067] The small raise boring bit 13 and the small raise boring rod 10 are disassembled. A large raise boring rod 15 is lowered to the tunnel 1 along the design direction of the vertical / inclined shaft. A large raise boring bit 16 is installed on the head of the large raise boring rod 15. The large raise boring rod 15 is withdrawn by the raise boring machine 9, driving the large raise boring bit 16 to reversely excavate the stratum along the designed central axis of the vertical / inclined shaft 6, and forming the vertical / inclined shaft 17 at one time according to a designed excavation line of a vertical / inclined shaft 7.

[0068] Further preferably, a diameter of the large raise boring rod 15 is larger than that of the small raise boring rod 10, and the large raise boring rod drives the large raise boring bit 16 to reversely excavate the stratum from bottom to top.

[0069] Further preferably, a diameter of the large raise boring bit 16 is greater than 4 m, and the large raise boring bit is installed at an end of the large raise boring rod 15 to excavate the stratum with the rise of the large raise boring rod 15 to form the vertical / inclined shaft 17.

[0070] Further preferably, the central axis of the vertical / inclined shaft 17 basically coincides with the designed central axis of the vertical / inclined shaft 6, and the deviation rate is close to 0.

[0071] Further preferably, in Step 3, the diameter of the reamer bit 11 is between 250 mm and 600 mm.

[0072] Further preferably, in Step 5, after the vertical / inclined shaft 17 is formed, a set of single-hook lifting systems is equipped to take on the functions of lowering materials and workers, the wall is built with integral metal formworks, seamless steel pipes are placed into concrete, and the shaft wall is poured. The above arrangement can be used to effectively support the vertical / inclined shaft 17 after being formed.

[0073] Further preferably, the reaming process is a process of breaking a large number of rocks. The model of reamer bits and the arrangement form of rock-breaking hobs need to be determined according to stratum rock conditions. Corresponding drilling parameters are made to achieve the purpose of drilling with the highest efficiency. The above bit selection enhances the adaptability, so as to ensure the adaptability to different rock strata.

[0074] Further preferably, the diameter size of the large raise boring rod 15 is selected to ensure that the large raise boring rod is not interfered by an inner wall of the pilot shaft 14 in the lowering process inside the pilot shaft 14, so that the axis of the large raise boring rod 15 coincides with the designed central axis of the vertical / inclined shaft 6. The above size selection ensures that the formed vertical / inclined shaft 17 is a shaft that just meets the designed central axis 6 of the vertical / inclined shaft in the final raise boring construction process, which ensures the forming accuracy and effectively overcomes the deviation influence of the original directional boring hole 8.Embodiment 2

[0075] The present disclosure provides a secondary shaft completion construction method based on a raise boring process. The present disclosure uses the following technical scheme. In the scheme, the boring direction of trepanning the directional boring hole and reaming the pilot hole is the forward boring direction, and the reamer boring direction of the small raise boring bit 13 and the large raise boring bit 16 is the raise boring direction. This embodiment takes the vertical shaft drilling construction of a raise boring machine as an example, and the steps are as follows.

[0076] S1: preparation is carried out before construction. A tunnel 1 is excavated in an underground rock body in advance. Prior to the process that the directional boring machine 3 is arranged on the ground corresponding to the tunnel, concrete is poured on the ground to form a foundation platform 2. The directional boring machine 3 is then fixed on the foundation platform 2 with foundation bolts, and then all the foundation bolts are completely covered with concrete.

[0077] S2: according to the use requirements of the directional boring machine 3, the directional boring machine 3 is arranged on the ground corresponding to the tunnel 1, and a directional boring bit 4 of φ195 mm, a plurality of stable boring rods and a directional boring rod are provided.

[0078] S3: the directional boring bit 4 is installed on the directional boring machine 3. A stable boring rod is then connected at a tail end of the directional boring bit to form the composite boring rod 5, and the directional boring machine is started to drive the composite boring rod 5 to drill into the stratum from top to bottom.

[0079] S4: a directional boring rod is fixedly connected at a tail end of the composite boring rod to form a new composite boring rod 5. The stratum is continuously drilled from top to bottom.

[0080] S5: S4 is carried out repeatedly. The directional boring rod and the stable boring rod are alternately connected until the directional boring hole 8 communicated with the tunnel is obtained. The composite boring rod is withdrawn, and the directional boring machine is disassembled.

[0081] S6: a maximum deviation δ between the central axis of the directional boring hole and the designed central axis of the vertical shaft is measured using a measuring instrument to be 0.7 m. the radius r of the small raise boring bit 13 is selected to be 1 m, which is more than 0.7 m.

[0082] S7: the raise boring machine 9 is installed according to the use requirements of the raise boring machine. The small raise boring rod 10, the φ350 mm reamer bit 11, the φ2 m small raise boring bit 13, the large raise boring rod 15 and the φ7 m large raise boring bit 16 are provided.

[0083] S8: the reamer bit 11 is installed at an end of the small raise boring rod 10. The small raise boring rod and the reamer bit are driven by the raise boring machine 9 to drill into the stratum from top to bottom along the directional boring hole to reach the tunnel, so as to form a pilot hole 12.

[0084] S9: the reamer bit 11 is disassembled, and the small raise boring bit 13 is assembled at the end of the small raise boring rod.

[0085] S10: the small raise boring bit 13 is withdrawn along the pilot hole 12 to drive the small raise boring bit 13 to reversely excavate the stratum to form a pilot shaft 14, wherein the pilot hole has a radius of 1 m. A maximum deviation between the central axis of the pilot shaft and the designed central axis of the vertical shaft is 0.7 m, which is smaller than the radius of the pilot hole and meets the secondary drilling requirement.

[0086] S11: the large raise boring rod 15 is lowered straight to the tunnel 1 along the designed central axis of the vertical shaft, and the large raise boring bit 16 is installed at the end of the large raise boring rod 15.

[0087] S12: the large raise boring rod 15 is withdrawn to drive the large raise boring bit 16 with a large size to excavate the stratum from bottom to top along the design direction of the vertical shaft to form the vertical shaft. The boundary line of the vertical shaft basically coincides with the boundary line of the designed vertical shaft.

[0088] S13: after the secondary expanding excavation of the raise boring machine forms a shaft, a set of single-hook lifting systems is equipped to take on the functions of lowering materials and workers. The wall is built with integral metal formworks. Seamless steel pipes are placed into concrete, and the shaft wall is poured.

Examples

embodiment 1

[0047]Referring to FIG. 1 to FIG. 8, a secondary shaft completion construction method based on a raise boring process includes the following steps.[0048]Step 1, construction of a directional boring hole 8 is carried out.

[0049]A tunnel 1 is excavated in an underground rock body in advance. A directional boring machine 3 is arranged and installed on the ground corresponding to the tunnel 1. A composite boring rod 5 and a directional boring bit 4 are installed on the directional boring machine 3, drilling into the stratum along a design direction of a vertical / inclined shaft and penetrating through the stratum, communicating with the tunnel 1 to complete the construction of directional boring hole 8. The composite boring rod 5 is then withdrawn.

[0050]Further preferably, in order to ensure the installation stability of the directional boring machine 3 and the subsequent normal drilling construction, before the directional boring machine 3 is arranged and installed, concrete is poured on...

embodiment 2

[0075]The present disclosure provides a secondary shaft completion construction method based on a raise boring process. The present disclosure uses the following technical scheme. In the scheme, the boring direction of trepanning the directional boring hole and reaming the pilot hole is the forward boring direction, and the reamer boring direction of the small raise boring bit 13 and the large raise boring bit 16 is the raise boring direction. This embodiment takes the vertical shaft drilling construction of a raise boring machine as an example, and the steps are as follows.[0076]S1: preparation is carried out before construction. A tunnel 1 is excavated in an underground rock body in advance. Prior to the process that the directional boring machine 3 is arranged on the ground corresponding to the tunnel, concrete is poured on the ground to form a foundation platform 2. The directional boring machine 3 is then fixed on the foundation platform 2 with foundation bolts, and then all th...

Claims

1. A secondary shaft completion construction method based on a raise boring process, comprising the following steps:Step 1, carrying out construction of a directional boring hole (8):excavating a tunnel (1) in an underground rock body in advance, arranging and installing a directional boring machine (3) on the ground corresponding to the tunnel (1), installing a composite boring rod (5) and a directional boring bit (4) on the directional boring machine (3), drilling into the stratum along a design direction of a vertical / inclined shaft and penetrating through the stratum, communicating with the tunnel (1) to complete the construction of directional boring hole (8), and then withdrawing the composite boring rod (5);Step 2, measuring a deviation of the directional boring hole (8):measuring a maximum deviation distance δ between an axis of the directional boring hole (8) and a designed central axis of a vertical / inclined shaft (6);Step 3, carrying out construction of a pilot hole (12):disassembling the directional boring machine (3), installing a raise boring machine (9), connecting a small raise boring rod (10) with a reamer bit (11), carrying out secondary hole brushing by drilling the reamer bit (11) from top to bottom along a directional boring hole (8) to form a pilot hole (12), and ensuring that the small raise boring rod (10) is not withdrawn;Step 4, carrying out construction of a pilot shaft (14):selecting a small raise boring bit (13) with a radius of r, in which r>δ is ensured, disassembling the reamer bit (11), replacing the reamer bit and installing the small raise boring bit (13) at an end of the small raise boring rod (10), withdrawing the small raise boring rod (10) to drive the small raise boring bit (13) to reversely excavate the stratum, and excavating along the direction of the pilot hole (12) to form a pilot shaft (14);Step 5, carrying out construction of the vertical / inclined shaft (17):disassembling the small raise boring bit (13) and the small raise boring rod (10), lowering a large raise boring rod (15) to the tunnel (1) along the design direction of the vertical / inclined shaft, installing a large raise boring bit (16) on the head of the large raise boring rod (15), withdrawing the large raise boring rod (15) by the raise boring machine (9), driving the large raise boring bit (16) to reversely excavate the stratum along the designed central axis of the vertical / inclined shaft (6), and forming the vertical / inclined shaft (17) at one time according to a designed excavation line of a vertical / inclined shaft (7).

2. The secondary shaft completion construction method based on the raise boring process according to claim 1, wherein before the directional boring machine (3) is arranged and installed in Step 1, concrete is poured on the ground to form a foundation platform (2), the directional boring machine (3) is then fixed on the foundation platform (2) with foundation bolts, and then all the foundation bolts are completely covered with concrete.

3. The secondary shaft completion construction method based on the raise boring process according to claim 1, wherein in Step 1, the composite boring rod (5) comprises a plurality of directional boring rods and stable boring rods; in the drilling process, the directional boring rod is installed on the directional boring machine (3), the directional boring bit (4) is installed on the head of the directional boring rod, a stable boring rod is then connected at a tail end of the directional boring bit (4) to form the composite boring rod (5), and the directional boring machine (3) is started to drive the composite boring rod (5) to drill into the stratum from top to bottom.

4. The secondary shaft completion construction method based on the raise boring process according to claim 3, wherein in the process that the composite boring rod (5) continues to drill, when the length of the composite boring rod (5) is insufficient, the corresponding directional boring rod and the stable boring rod are fixedly connected at a tail end of the composite boring rod (5) to form a new composite boring rod, the stratum is continuously drilled from top to bottom, the directional boring rod and the stable boring rod are repeatedly and alternately connected until the directional boring hole (8) communicated with the tunnel (1) is obtained, the composite boring rod (5) is withdrawn, and the directional boring machine (3) is disassembled.

5. The secondary shaft completion construction method based on the raise boring process according to claim 4, wherein in the process of downward drilling of the directional boring rod, a certain deviation occurs at a joint of the directional boring rods, the directional boring rod is subjected to bending stress deformation due to the pressure, and the deviation at the joint of the directional boring rods is superimposed with the bending stress deformation of the directional boring rod itself, so that the entire directional boring rod deviates from the designed central axis of the vertical / inclined shaft (6) toward the directional boring hole (8) going downward in a spiral manner.

6. The secondary shaft completion construction method based on the raise boring process according to claim 5, wherein: a diameter of the directional boring hole (8) ensures the directional boring rod to move freely up and down therein, but the diameter is smaller than that of the small raise boring rod (10); a central axis of the directional boring hole (8) is spiral, and there is a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft (6).

7. The secondary shaft completion construction method based on the raise boring process according to claim 6, wherein in Step 4, the central axis of the pilot shaft (14) basically coincides with the central axis of the pilot hole (12) in a spiral manner, and there is also a certain deviation rate with respect to the designed central axis of the vertical / inclined shaft (6), but the radius r of the pilot shaft (14) is ensured to be larger than the deviation of the pilot hole (12), so that the large raise boring rod (15) is lowered straight to the tunnel (1) at the bottom along the designed central axis of the vertical / inclined shaft (6).

8. The secondary shaft completion construction method based on the raise boring process according to claim 1, wherein a diameter of the large raise boring rod (15) is larger than that of the small raise boring rod (10), and the large raise boring rod drives the large raise boring bit (16) to reversely excavate the stratum from bottom to top.

9. The secondary shaft completion construction method based on the raise boring process according to claim 8, wherein a diameter of the large raise boring bit (16) is greater than 4 m, and the large raise boring bit is installed at an end of the large raise boring rod (15) to excavate the stratum with the rise of the large raise boring rod (15) to form the vertical / inclined shaft (17).

10. The secondary shaft completion construction method based on the raise boring process according to claim 8, wherein the central axis of the vertical / inclined shaft (17) basically coincides with the designed central axis of the vertical / inclined shaft (6), and the deviation rate is close to 0.

11. The secondary shaft completion construction method based on the raise boring process according to claim 8, wherein in Step 3, the diameter of the reamer bit (11) is between 250 mm and 600 mm.

12. The secondary shaft completion construction method based on the raise boring process according to claim 1, wherein in Step 5, after the vertical / inclined shaft (17) is formed, a set of single-hook lifting systems is equipped to take on the functions of lowering materials and workers, the wall is built with integral metal formworks, seamless steel pipes are placed into concrete, and the shaft wall is poured.

13. The secondary shaft completion construction method based on the raise boring process according to claim 1, wherein the reaming process is a process of breaking a large number of rocks, the model of reamer bits and the arrangement form of rock-breaking hobs need to be determined according to stratum rock conditions, and corresponding drilling parameters are made to achieve the purpose of drilling with the highest efficiency.

14. The secondary shaft completion construction method based on the raise boring process according to claim 1, wherein the diameter size of the large raise boring rod (15) is selected to ensure that the large raise boring rod is not interfered by an inner wall of the pilot shaft (14) in the lowering process inside the pilot shaft (14), so that the axis of the large raise boring rod (15) coincides with the designed central axis of the vertical / inclined shaft (6).

Images