Construction method for one-time excavation through benching method

Abstract

The construction method comprises the following steps: after a predetermined tunneling task of an upper step is finished, a tunneling part carries out tunneling operation of a lower step in a region where the construction of the lower step is located; upper step construction operation is synchronously carried out on the upper step; after the lower step tunneling operation is completed, lower step construction operation is synchronously carried out; before the operation of the upper floor stand, the unit vehicle is moved, the tunneling part is moved to the tunnel face to carry out the next cycle of upper step tunneling operation, and parallel operation of upper step construction and lower step construction is realized through the cycle; according to the scheme, the problems that mechanical equipment of all functional blocks in the front excavation primary support process of the front tunnel face is difficult to connect and parallel construction cannot be achieved are solved, the primary support ring forming process of new Austrian method construction is completed through mechanical and integrated rack integrated equipment, the safety step pitch is effectively controlled, and the excavation efficiency and safety are improved.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel construction, and in particular to a step-method one-time excavation construction method. Background Art

[0002] In the construction of the New Austrian Tunneling Method, the first process of the operation cycle of tunnel construction includes upper excavation, slag discharge and initial support operations. In the step method, the upper step construction needs to be carried out first, and then the lower step construction. The upper step construction follows a specific process flow, namely excavation, slag discharge, measurement and marking, frame erection, anchor rod and shotcrete; the lower step construction also follows a specific process flow, namely excavation, slag discharge, frame erection, anchor rod, shotcrete and slag turning. The two are independent of each other. Usually, the lower step construction is carried out after the upper step construction is completed. There is a conflict between the processes, and the mechanical devices used will interfere. Therefore, in the existing process, the upper and lower step construction usually takes a long time, resulting in low construction efficiency and affecting the overall construction progress. At the same time, due to the long time interval between the upper and lower step construction, it will take a long time to form a closed support ring inside the tunnel. The area where the closed support ring is not formed in the tunnel will have a risk of collapse, that is, the longer the time interval between the upper and lower step construction, the greater the risk of collapse. Summary of the invention

[0003] The purpose of the present invention is to provide a construction method of one-time excavation by the step method to address the above-mentioned shortcomings, thereby solving the problem in the prior art that the time interval between the upper and lower step construction is long, resulting in low construction efficiency and affecting the overall construction progress. At the same time, it solves the problem that the time interval between the upper and lower step construction is long, which will result in a long time for forming a closed support ring inside the tunnel, and the area where the closed support ring is not formed in the tunnel will be at risk of collapse.

[0004] The present invention is achieved through the following scheme:

[0005] This solution provides a construction method of one-step excavation using the step method, including the following steps:

[0006] After the scheduled excavation task of the upper step is completed, the excavation work of the lower step is carried out, and the support work of the upper step is carried out simultaneously; after the excavation work of the lower step is completed, the support work of the upper and lower steps is carried out simultaneously;

[0007] Before the erection of the upper support work, the unit is moved and the excavation unit is moved to the face for the next cycle of upper step excavation work. This cycle realizes parallel operation of upper and lower step construction.

[0008] The excavation unit moves to the area where the lower step construction is located by sliding to carry out the lower step excavation operation.

[0009] The scheduled excavation task of the upper step is completed, specifically, according to the site requirements, after the scheduled excavation task of the first side excavation component is completed, the first side excavation component is ready to slide to the area where the lower step construction is located; the second side excavation component is still performing the scheduled excavation task in the scheduled area;

[0010] Alternatively, according to the site requirements, after the scheduled excavation task of the second side excavation assembly is completed, the second side excavation assembly is ready to slide to the area where the lower step construction is located; the first side excavation assembly still performs the scheduled excavation task in the scheduled area;

[0011] Alternatively, according to on-site requirements, the excavation components on the first side and the second side simultaneously prepare to slide to the area where the lower step construction is located after the scheduled excavation task is completed; the excavation components on the first side and the second side simultaneously perform the scheduled excavation task in the area where the lower step construction is located.

[0012] The upper step support operation includes one or more construction operations of upper step shotcrete, erection of frames, and anchor bolting operations.

[0013] The upper step support operation will be accompanied by the upper step slag discharge operation, and its specific forms include:

[0014] According to the construction procedures, the slag removal operation and the upper step shotcrete operation are carried out, or the slag removal operation and the upper step frame erection operation are carried out; or the slag removal operation and the upper step anchor rod anchoring operation are carried out; or the slag removal operation, the upper step shotcrete operation and the frame erection operation are carried out in parallel.

[0015] During the upper step support operation, the upper step spraying operation and the upper step frame erection operation are carried out; or the upper step spraying operation and the upper step anchor bolting operation are carried out; or the upper step frame erection operation and the upper step anchor bolting operation are carried out.

[0016] The lower step support operation includes one or more construction operations of lower step shotcrete, erection of frames, anchor bolting and backfilling.

[0017] The lower step support operation will be accompanied by the lower step slag turning operation, and its specific forms include:

[0018] According to the construction procedures, the slag turning operation and the lower step initial spraying operation are carried out; or the slag turning operation and the lower step frame erection operation are carried out; or the slag turning operation and the lower step anchor bolting operation are carried out; or the slag turning operation and the lower step shotcreting operation are carried out; or the slag turning operation and the lower step shotcreting operation are carried out in parallel; or the slag turning operation, the upper step shotcreting operation and the anchor bolting operation are carried out in parallel.

[0019] During the lower step support operation, the lower step spraying operation and the lower step scaffolding operation are carried out; or the lower step spraying operation and the lower step anchor bolting operation are carried out.

[0020] The excavation unit slides to the area where the lower step construction is located. Specifically, a sliding unit for the excavation unit to move is provided at the bottom position of the top wall of the frame, and the excavation unit slides from the lower side position of the top wall of the frame to the area where the lower step construction is located.

[0021] The slag discharge on the upper step is specifically that a bucket which can rotate relative to the frame and slide along the width direction of the frame is arranged on the frame, and a conveying part which can convey the slag is arranged at the bottom of the frame. By rotating the bucket, the slag within the radiation range of the bucket can be excavated and sent to the conveying part, and transported away from the tunnel face through the conveying part; at the same time, by moving the bucket along the width direction of the frame, the radiation range of the bucket can cover the slag producing area of ​​the entire tunnel face.

[0022] The conveying part discharges the slag from the bottom of the stand; or discharges the slag from at least one side of the stand; or discharges the slag from the bottom of the stand first, and then passes through the stand to discharge the slag from at least one side of the stand.

[0023] The upper step shotcreting operation includes the initial shotcreting operation. Specifically, a storage device is provided at the rear end of the platform, and an upper step shotcreting assembly is provided on the step. The upper step shotcreting assembly is connected to the storage device. The initial shotcreting operation is carried out toward the excavation area of ​​the face through the upper step shotcreting assembly.

[0024] The upper step erection and anchor bolting operations are specifically as follows: arch anchor arms that can move along the length direction of the frame are set on both sides and the top of the frame; the arch frame is transported and erected by the arch anchor arms, and after the erection operation is completed, the anchor bolt anchoring operation is carried out by the anchor arch arms; the upper step shotcreting operation includes re-spraying operation, specifically, the upper step shotcreting assembly is used to re-spray the assembled arch frames on both sides of the tunnel.

[0025] The slag turning operation at the lower step is specifically to transport the slag away from the area where the invert arch is to be erected by a loader, pile a part of the slag on the side of the area where the invert arch is to be erected, and transport the remaining slag away from the tunnel.

[0026] The lower step erection operation is specifically as follows: an inverted arch transport assembly is provided at the rear end of the platform, the inverted arch is transported to a predetermined position by the inverted arch transport assembly, and the construction personnel dock and lock the inverted arch with the upper arch frame to complete the erection operation of the inverted arch.

[0027] The anchor bolting and shotcreting operations of the lower step are specifically as follows: a hanging arch anchor arm is provided at the rear end of the gantry, and the locking foot anchor bolt operation is performed on the inverted arch through the hanging arch anchor arm, and / or the system anchor bolt operation is performed on the inverted arch in the specified area according to the specifications; the shotcreting operation of the lower step is to perform shotcreting operation on the assembled and fixed inverted arch through the lower step shotcrete assembly.

[0028] This scheme provides a specific step method for one-step excavation, which specifically includes the following steps:

[0029] Step 1: Carry out upper step excavation work at the upper step;

[0030] Step 2: After the excavation work of the upper step is completed, the upper step slag removal work is carried out, and at the same time, the upper step arch frame transfer work is carried out in the upper step construction area; at this time, the lower step excavation work is carried out at the lower step;

[0031] Step 3: After the upper step arch frame transfer operation is completed, the upper step frame erection operation is carried out, and at the same time, the upper step slag removal operation is continued according to the actual slag material conditions on site; at this time, the lower step slag turning operation is carried out; before the upper step frame erection operation, the unit needs to be moved and the excavation unit needs to slide to the tunnel face for the next cycle of upper step excavation operation;

[0032] Step 4: After the upper stage erection work is completed, the upper step mesh welding work and the upper step locking foot anchor work are carried out at the arch frame; at this time, the lower step erection work and the invert arch cleaning work are carried out at the lower step;

[0033] Step 5: After the locking foot anchoring operation of the upper step is completed, the leading anchoring operation and the system anchoring operation of the upper step are carried out; at this time, the locking foot anchoring operation of the lower step, the erection operation of the lower step invert arch, the lower step spraying operation and the invert arch re-spraying operation are carried out at the lower step;

[0034] Step 6: After the upper step anchoring operation is completed, the upper step spraying operation is carried out. At this time, the spraying position is located at the bottom of both sides of the arch frame. At this time, the lower step performs the invert backfill operation;

[0035] Step seven: After the grouting operation of the lower part of the upper step is completed, the grouting operation of the remaining parts of the upper step is carried out, and the next cycle of upper step excavation operation is carried out simultaneously.

[0036] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0037] 1. This solution provides a solution to the difficulties in connecting the mechanical equipment of various functional blocks in the initial support process of the front excavation face and the inability to carry out parallel construction. Through mechanized and integrated gantry integrated equipment, the initial support ring process of the New Austrian Tunneling Method construction is completed, and the safe step distance is effectively controlled to increase excavation efficiency and safety, improve the labor intensity of workers, and improve construction safety.

[0038] 2. The present invention is a walking mobile unit for one-time excavation using the step method. Through the process modules integrated into the all-in-one machine, the transfer and cost of other supporting engineering machinery are reduced, and the mechanized operation of the next road is used to improve the tunnel construction working environment, improve the distribution efficiency of excavation and slag discharge, and reduce the waiting time of mixer trucks. The present invention solves the problem of coordinated construction equipment for the step method in medium-span tunnels with good surrounding rock conditions. Through the equipment modules for synchronous excavation of the front and rear steps, parallel slag discharge, and initial support operations, the process of timely ring formation on the face is completed, thereby improving the utilization rate of personnel and equipment. While operating in parallel, the reasonable distribution between processes is increased, and the processes can be connected to complete the process connection of the step method excavation method and the New Austrian Tunneling Method support.

[0039] Reference numerals

[0040] Figure 1 This is a structural schematic diagram of the walking type mobile unit of Example 2;

[0041] Figure 2 This is a schematic diagram of the parallel construction of the upper and lower steps;

[0042] Figure 3 A flowchart for one type of construction work as a whole;

[0043] Figure numerals: 1. trolley; 2. excavation section; 3. slag discharge section; 4. arch anchor section; 5. arch erection section; 6. shotcrete section; 7. upper step construction section; 8. lower step construction section. DETAILED DESCRIPTION

[0044] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0045] Any feature disclosed in this specification (including any additional claims and abstract), unless otherwise stated, may be replaced by other equivalent or alternative features having similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0046] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a predetermined direction, be constructed and operated in a predetermined direction, and therefore cannot be understood as a limitation on the present invention.

[0047] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0048] Example 1

[0049] The present invention provides a technical solution:

[0050] A construction method of one-step excavation by step method, comprising the following steps:

[0051] After the scheduled excavation task of the upper step is completed, the excavation work of the lower step is carried out, and the support work of the upper step is carried out simultaneously; after the excavation work of the lower step is completed, the support work of the upper and lower steps is carried out simultaneously;

[0052] Before the erection of the upper support work, the unit is moved and the excavation unit is slid to the face for the next cycle of upper step excavation work. This cycle realizes parallel operation of upper and lower step construction.

[0053] Since the excavation work of the upper step takes a long time, in this method, the excavation unit 2 can slide back to the heading face to carry out the excavation work of the upper step after completing the excavation work of the lower step, or the excavation unit can be independently set in the front and rear areas of the platform to carry out excavation independently. At this time, the lower step support work continues in the lower step construction area. During the upper step construction, the upper step excavation work of the excavation unit 2 can be carried out in parallel with other operation procedures of the upper step.

[0054] In this scheme, the scheduled excavation task of the upper step is completed, which specifically means that according to the site requirements, after the scheduled excavation task of the first side excavation component is completed, the first side excavation component is ready to slide to the area where the lower step construction is located; the second side excavation component is still performing the scheduled excavation task at the scheduled area (tunnel face);

[0055] Alternatively, according to the site requirements, after the scheduled excavation task of the second side excavation assembly is completed, the second side excavation assembly is ready to slide to the area where the lower step construction is located; the first side excavation assembly is still performing the scheduled excavation task at the predetermined area (tunnel face);

[0056] Alternatively, according to the on-site requirements, the excavation components on the first side and the second side are simultaneously prepared to slide to the area where the lower step construction is located after the scheduled excavation task is completed; the excavation components on the first side and the second side simultaneously perform the scheduled excavation task in the area where the lower step construction is located;

[0057] Based on the above method, this scheme can choose to slide a single excavation section or all excavation sections according to the actual excavation situation on site, so as to make the whole excavation operation more flexible and adapt to the complex tunnel environment. In this scheme, the first side excavation component and the second side excavation component are excavation components in different directions; the predetermined excavation task in this scheme is to carry out excavation according to construction needs, such as after the first side excavation section excavates 1m, the first side excavation section slides to the lower frame for excavation, or after the second side excavation section excavates 0.8m, the second side excavation section slides to the lower frame for excavation, and so on.

[0058] The upper step support operation includes one or more construction operations of upper step shotcrete, frame erection and anchor bolting;

[0059] The upper step support operation will be accompanied by the upper step slag discharge operation, and its specific forms include:

[0060] According to the construction process, the upper step slag removal operation and the upper step shotcreting operation are carried out, or the upper step slag removal operation and the upper step frame erection operation are carried out; or the upper step slag removal operation and the upper step anchor bolt anchoring operation are carried out; or the upper step slag removal operation, the upper step shotcreting operation and the frame erection operation are carried out in parallel;

[0061] During the upper step support operation, the upper step spraying operation and the upper step frame erection operation are carried out; or the upper step spraying operation and the upper step anchor bolting operation are carried out; or the upper step frame erection operation and the upper step anchor bolting operation are carried out.

[0062] In this construction method, while excavation work is being carried out on the lower step, one or more processes are carried out in parallel on the upper step according to actual process requirements, effectively utilizing the excavation time of the lower step to achieve more efficient construction work. In this scheme, during the construction work on the upper step, multiple processes can be operated in parallel, and the construction work on the upper and lower steps is also parallel.

[0063] The lower step support operation includes one or more of the following operations: lower step shotcreting, erection, anchor bolting and backfilling;

[0064] The lower step support operation will be accompanied by the lower step slag turning operation, and its specific forms include:

[0065] According to the construction procedures, the lower step slag turning operation and the lower step initial spraying operation are carried out; or the lower step slag turning operation and the lower step frame erection operation are carried out; or the lower step slag turning operation and the lower step anchor bolt anchoring operation are carried out; or the lower step slag turning operation and the lower step shotcreting operation are carried out; or the lower step slag turning operation, the upper step shotcreting operation and the anchor bolt anchoring operation are carried out in parallel; or the lower step slag turning operation, the upper step shotcreting operation and the anchor bolt anchoring operation are carried out in parallel;

[0066] During the lower step support operation, the lower step spraying operation and the lower step scaffolding operation are carried out; or the lower step spraying operation and the lower step anchor bolting operation are carried out.

[0067] In this scheme, when the lower step construction is carried out, a single or multiple processes are carried out in parallel according to actual needs in the construction process of the lower step. Combined with the previous parallel construction of the upper step construction, and the parallel construction of the upper and lower steps, this scheme can greatly improve the efficiency of tunnel construction through triple parallel construction.

[0068] In this construction method, the excavation unit 2 slides to the area where the lower step is constructed. Specifically, a sliding unit for the excavation unit 2 to move is provided at the bottom of the top wall of the platform. The excavation unit 2 slides from the lower side of the top wall of the platform to the area where the lower step is constructed.

[0069] Based on the above structure, since the spraying part 6 and some components of the arch part 5 will be set at the upper position of the top wall of the gantry, the sliding part is set at the bottom position of the top wall of the gantry. This can prevent the excavation part 2 from interfering with other mechanical structures during the sliding process, and can achieve better coherent coordination between the various mechanisms, so that the parallel construction of the entire upper and lower steps can proceed smoothly.

[0070] In this method, the slag discharge on the upper step can be specifically achieved by providing a bucket on the frame that can rotate relative to the frame and slide along the width direction of the frame, and a conveying part that can convey the slag is provided at the bottom of the frame. By rotating the bucket, the slag within the radiation range of the bucket can be excavated and sent to the conveying part, and then transported away from the tunnel face through the conveying part; at the same time, by moving the bucket along the width direction of the frame, the radiation range of the bucket can cover the slag producing area of ​​the entire tunnel face.

[0071] The conveying part discharges the slag from the bottom of the stand; or discharges the slag from at least one side of the stand; or discharges the slag from the bottom of the stand first, and then passes through the stand to discharge the slag from at least one side of the stand.

[0072] In this solution, a bucket that can rotate and slide relative to the frame is provided, so that the bucket can cover a wider range during the process of excavating and transporting slag. At the same time, the bucket can also be used more flexibly to avoid interference with other working parts, providing the possibility for parallel construction. The excavation part 2 is arranged at the lower side of the top wall of the frame, and the connection part between the bucket and the frame is located at the upper side of the top wall of the frame. The two do not interfere with each other during transportation.

[0073] In this method, the upper step shotcreting operation may include the initial shotcreting operation. A material storage device is provided at the rear end of the platform, and an upper step shotcreting assembly is provided on the step. The upper step shotcreting assembly is connected to the material storage device. The initial shotcreting operation is carried out toward the excavation area of ​​the face through the upper step shotcreting assembly.

[0074] In this solution, by providing a storage device capable of storing slurry, the upper step spraying assembly can be used to spray the area to be sprayed at any time without waiting for the transportation of the slurry truck. By spraying the excavated area, the face can be supported to avoid collapse.

[0075] In this method, a slurry circulation unit is provided in the storage device, through which the slurry circulates inside to avoid the slurry from drying up. The storage device intermittently receives slurry replenishment from the transport vehicle, providing a basis for the spraying operation of the integrated unit at any time.

[0076] In this method, the step erection work and anchor bolt anchoring work are specifically as follows: arch anchor arms that can move along the length direction of the frame are set on both sides and the top of the frame; the arch frame is transported and the arch is erected by the arch anchor arms, and after the erection work is completed, the anchor bolt anchoring work is carried out by the anchor arch arms.

[0077] The anchor bolting operation specifically involves driving locking foot anchor bolts into the assembled arch frame, and / or driving system anchor bolts into the arch frame in the specified area according to the specifications, and / or driving advance anchor bolts based on the comparison between the excavation depth and the projection of the previous advance anchor bolt on the horizontal plane.

[0078] The locking anchor rock drilling operation and the system anchor rock drilling operation are carried out through the drilling arch arms on both sides; the advance anchor rock drilling operation is carried out through the anchor arm; at this time, the transport component transports the anchor to the predetermined position;

[0079] After the locking foot anchor rod rock drilling operation, the locking foot anchor rod is inserted into the drilled hole, and then the locking foot anchor rod is fixed to the primary support arch frame by the fixing parts; at the same time, the operator performs the left and right side system anchor rod rock drilling operations respectively through the drilling arch arm.

[0080] After the system anchor rock drilling operation and the advance anchor rock drilling operation are completed, the system anchor and the advance anchor are transported to the designated location through the transportation system, and the system anchor and the advance anchor are driven into the drilled holes.

[0081] When inserting locking foot anchors, system anchors and advance anchors into holes, anchor fixing agents can be filled in to increase the anchoring effect of the anchors.

[0082] The anchor bolting operations in this scheme include locking foot anchor bolting, system anchor bolting and advance anchor bolting. After the arch frame is installed, it is necessary to carry out locking foot anchor bolting on the arch frame at the bottom of the upper construction surface, so as to achieve the fixed installation of the bottom of the arch frame. During the advancement of the arch frame installation in the tunnel, the system anchor bolts need to be driven at a specified distance along the depth direction of the tunnel. The system anchor bolts are driven into the positions of both sides of the tunnel with a predetermined length of anchor bolts, and the system anchor bolts are welded to the arch frame as a whole, which is used to increase the whole arch frame system and The fixing effect of the rock mass improves the safety of the arch system. Therefore, the system anchoring operation needs to be carried out according to the specified size. The advance anchoring operation is to drive the advance anchor in the oblique upward direction of the heading face. It is used to support the area before the heading face during the excavation of the heading face by the excavation mechanism to avoid large-scale collapse. Therefore, the advance anchoring operation needs to be carried out according to the overall advancement direction toward the heading face. When the end position of the previous advance anchor in the vertical direction is about to be reached, the next advance anchor needs to be driven in.

[0083] In this method, the upper step shotcreting operation may include a re-shotcreting operation, specifically, re-shotcreting the assembled arch frames on both sides of the tunnel through the upper step shotcreting assembly.

[0084] In this scheme, both the initial spraying operation and the re-spraying operation do not need to wait for the cement tanker, and the slurry can be directly drawn from the storage device for spraying operation.

[0085] In this construction method, the slag turning operation at the lower step is specifically to transport the slag away from the area where the invert arch is to be erected by a loader, pile a part of the slag on the side of the area where the invert arch is to be erected, and transport the remaining slag away from the tunnel.

[0086] After the invert is assembled, the working area needs to be backfilled, so some slag needs to be reserved and piled on the side to facilitate the subsequent backfilling operation.

[0087] In this method, the initial spraying operation of the lower step is specifically that a lower step spraying assembly is arranged at the rear end of the platform, and the lower step spraying assembly is connected to the material storage device. After the slag turning operation of the lower step is completed, the initial spraying operation is carried out on the excavation area through the lower step spraying assembly.

[0088] In this solution, an upper step spraying assembly and a lower step spraying assembly are respectively provided, which are independent of each other and do not need to be converted to each other. At the same time, since both are connected to the storage device, the spraying operation can be carried out at any time according to the sequence of the construction operation, and there is no need to wait for the cement tanker.

[0089] In this construction method, the lower step erection operation is specifically as follows: an inverted arch transport assembly is provided at the rear end of the platform, the inverted arch is transported to a predetermined position by the inverted arch transport assembly, and the construction personnel dock and lock the inverted arch with the upper arch frame to complete the erection operation of the inverted arch.

[0090] The anchor bolting operation and re-spraying operation of the lower step are specifically as follows: a hanging arch anchor arm is set at the rear end of the platform, and the locking foot anchor operation is carried out on the inverted arch through the hanging arch anchor arm, and / or the system anchor operation is carried out on the inverted arch in the specified area according to the specifications; the re-spraying operation of the lower step is to re-spray the assembled and fixed inverted arch through the lower step shotcrete assembly.

[0091] In this construction method, the backfilling operation of the lower step is specifically to use a loader to backfill the slag reserved on the side of the invert construction operation into the invert assembly area.

[0092] This solution reduces the transfer and cost of other supporting engineering machinery through the process modules integrated into the all-in-one machine, improves the tunnel construction working environment through the mechanized operation of the next road, improves the distribution efficiency of excavation and slag discharge, and reduces the waiting time of mixer trucks, etc. The present invention solves the problem of coordinated construction equipment of the step method in medium-span tunnels with good surrounding rock conditions. Through the equipment modules of synchronous excavation of the front and rear steps, parallel slag discharge and initial support operations, the process of timely ring formation on the heading face is completed, improving the utilization rate of personnel and equipment. While operating in parallel, the reasonable distribution between processes is increased, and the processes can be connected to complete the process connection of the step method excavation method and the new Austrian method support.

[0093] This embodiment also provides a more specific process, such as Figure 3 As shown ( Figure 3 The processes in the same dotted box represent the processes that are carried out simultaneously); the specific steps are as follows:

[0094] Step 1: Perform the upper step excavation operation at the upper step; while the upper step excavation operation is performed at the upper step of this cycle, it will also be accompanied by the shotcrete operation of the previous cycle (i.e., the shotcrete operation of the lower part of the upper step described in step 7);

[0095] Step 2: After the excavation work of the upper step is completed, the upper step slag removal work is carried out, and at the same time, the upper step arch frame transfer work is carried out in the upper step construction area; at this time, the lower step excavation work is carried out at the lower step;

[0096] Step 3: After the upper step arch frame transfer operation is completed, the upper step frame erection operation is carried out, and at the same time, the upper step slag removal operation is continued according to the actual slag material conditions on site; at this time, the lower step slag turning operation is carried out; it should be noted that before the upper step frame erection operation, the unit needs to be moved and the excavation unit needs to slide to the tunnel face for the next cycle of upper step excavation operation;

[0097] Step 4: After the erection of the upper stage is completed, the mesh welding operation and the locking foot anchoring operation are carried out at the arch frame. It should be noted that the mesh welding is also a related process of the erection operation, so this is equivalent to achieving the parallel anchoring of the erection and the anchoring; this step is also carried out at the lower step to carry out the lower step erection operation and the invert arch cleaning operation;

[0098] Step 5: After the locking foot anchoring operation of the upper step is completed, the leading anchoring operation and the system anchoring operation of the upper step are carried out; at this time, the locking foot anchoring operation of the lower step, the erection operation of the lower step invert arch, the re-spraying operation of the lower step and the re-spraying operation of the invert arch are carried out at the lower step;

[0099] Step 6: After the upper step anchoring operation is completed, the upper step spraying operation is carried out. At this time, the spraying position is located at the bottom of both sides of the arch frame. At this time, the lower step performs the invert backfill operation;

[0100] Step 7: After the grouting operation of the lower part of the upper step is completed, the grouting operation of the rest of the upper step is carried out, and the next cycle of upper step excavation operation is carried out simultaneously. The lower part of the upper step in this step refers to the area close to the ground. The lower part of the upper step is sprayed first because the next cycle of excavation operation is about to be carried out. If the lower part of the step is not sprayed as soon as possible, the slag generated during the excavation operation will accumulate and cover the lower part of the upper step, making it difficult to spray the lower part of the upper step.

[0101] Based on the applicant’s verification, Figure 3 The construction process organization shown in the figure effectively increases the rational distribution between processes, and can connect the processes to complete the bench excavation method and the New Austrian Tunneling Method support process, thereby improving the utilization rate of personnel and equipment. The synchronous operation of the upper and lower steps can also make the face of the tunnel form a ring faster and in time, reducing the risk of weak initial support and reducing the safety hazards of the construction project.

[0102] Example 2

[0103] like Figure 1 and Figure 2 As shown; the present invention provides a technical solution:

[0104] A walking mobile unit for single-step excavation using a step method, which at least includes but is not limited to a platform for supporting various functional components, the platform is divided into an upper step construction section 7 and a lower step construction section 8, an excavation section 2 is arranged on the platform, and the excavation section 2 can move across the upper step construction section 7 and the lower step construction section 8 along the length direction of the platform; a slag discharge section 3 is also arranged in the upper step construction section 7; an arch anchor section 4 cooperating with anchor bolt anchoring operation, an arch erecting section 5 cooperating with arch erecting operation, and a shotcrete section 6 cooperating with shotcrete operation are respectively arranged in the upper step construction section 7 and the lower step construction section 8.

[0105] Based on the above structure, by setting a stand including an upper step construction part 7 and a lower step construction part 8, the excavation, arch erection, anchor bolting and re-spraying operations of the upper and lower steps can be realized synchronously. Since the operation time is long during the upper step construction, the prior art will wait until the upper step construction is completed before the lower step construction, which will cause a great waste of time. This scheme synchronously carries out the lower step construction within the time range of the long-term upper step construction, realizes the parallel construction of the upper and lower steps, and can greatly improve the construction efficiency. The excavation part 2 in this scheme can slide to the lower step construction area after the upper step excavation operation is completed to carry out the excavation operation, while the remaining processes in the upper step construction are carried out normally.

[0106] As an example, the slag discharge part 3 discharges slag from the bottom of the frame; or discharges slag from at least one side of the frame; or discharges slag from the bottom of the frame first, and then passes through the frame to discharge slag from at least one side of the frame.

[0107] Based on the above structure, since slag is easily accumulated at the bottom of the tunnel face, the slag discharge part 3 can quickly collect the slag at the bottom of the frame. At the same time, in order to avoid interference with the rear side parts of the frame, the slag discharge part 3 is set to a "Z"-shaped structure that first discharges slag from the frame, then passes through the side position of the frame, and finally discharges slag from the side of the frame. In this way, the slag discharge operation can be carried out more efficiently.

[0108] 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 and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A construction method of one-step excavation by step method, characterized in that: The steps include: After the scheduled excavation task of the upper step is completed, the excavation work of the lower step is carried out, and the support work of the upper step is carried out simultaneously; after the excavation work of the lower step is completed, the support work of the upper and lower steps is carried out simultaneously; Before the erection of the upper support work, the unit is moved and the excavation unit is moved to the face for the next cycle of upper step excavation work. This cycle realizes parallel operation of upper and lower step construction.

2. A step method one-time excavation construction method as claimed in claim 1, characterized in that: The excavation unit moves to the area where the lower step construction is located by sliding to carry out the lower step excavation operation.

3. The step method of one-step excavation construction method as claimed in claim 1, characterized in that: The scheduled excavation task of the upper step is completed, specifically, according to the site requirements, after the scheduled excavation task of the first side excavation component is completed, the first side excavation component is ready to slide to the area where the lower step construction is located; The second side excavation component still performs the predetermined excavation task in the predetermined area; Alternatively, according to the site requirements, after the scheduled excavation task of the second side excavation assembly is completed, the second side excavation assembly is ready to slide toward the area where the lower step construction is located; The first side excavation component is still performing a predetermined excavation task at a predetermined area; Alternatively, according to on-site requirements, the excavation components on the first side and the second side simultaneously prepare to slide to the area where the lower step construction is located after the scheduled excavation task is completed; the excavation components on the first side and the second side simultaneously perform the scheduled excavation task in the area where the lower step construction is located.

4. The step method of one-step excavation construction method as claimed in claim 1, characterized in that: The upper step support operation includes one or more construction operations of upper step shotcrete, erection of frames, and anchor bolting operations.

5. A step method one-time excavation construction method as claimed in claim 4, characterized in that: The upper step support operation will be accompanied by the upper step slag discharge operation, and its specific forms include: According to the construction procedures, the slag removal operation and the upper step shotcrete operation are carried out, or the slag removal operation and the upper step frame erection operation are carried out; or the slag removal operation and the upper step anchor rod anchoring operation are carried out; or the slag removal operation, the upper step shotcrete operation and the frame erection operation are carried out in parallel.

6. A step method one-time excavation construction method as claimed in claim 4, characterized in that: During the upper step support operation, the upper step spraying operation and the upper step frame erection operation are carried out; or the upper step spraying operation and the upper step anchor bolting operation are carried out; or the upper step frame erection operation and the upper step anchor bolting operation are carried out.

7. A step method one-time excavation construction method as claimed in any one of claims 1 to 6, characterized in that: The lower step support operation includes one or more construction operations of lower step shotcrete, erection of frames, anchor bolting and backfilling.

8. A step method one-time excavation construction method as claimed in claim 7, characterized in that: The lower step support operation will be accompanied by the lower step slag turning operation, and its specific forms include: According to the construction procedures, the slag turning operation and the lower step initial spraying operation are carried out; or the slag turning operation and the lower step frame erection operation are carried out; or the slag turning operation and the lower step anchor bolting operation are carried out; or the slag turning operation and the lower step shotcreting operation are carried out; or the slag turning operation and the lower step shotcreting operation are carried out in parallel; or the slag turning operation, the upper step shotcreting operation and the anchor bolting operation are carried out in parallel.

9. The step method of one-step excavation construction method as claimed in claim 7, characterized in that: During the lower step support operation, the lower step spraying operation and the lower step scaffolding operation are carried out; or the lower step spraying operation and the lower step anchor bolting operation are carried out.

10. The step method one-time excavation construction method as claimed in claim 2, characterized in that: The excavation unit slides to the area where the lower step construction is located. Specifically, a sliding unit for the excavation unit to move is provided at the bottom position of the top wall of the frame, and the excavation unit slides from the lower side position of the top wall of the frame to the area where the lower step construction is located.

11. The step method one-time excavation construction method as claimed in claim 1, characterized in that: The slag discharge on the upper step is specifically that a bucket which can rotate relative to the frame and slide along the width direction of the frame is arranged on the frame, and a conveying part which can convey the slag is arranged at the bottom of the frame. By rotating the bucket, the slag within the radiation range of the bucket can be excavated and sent to the conveying part, and transported away from the tunnel face through the conveying part; at the same time, by moving the bucket along the width direction of the frame, the radiation range of the bucket can cover the slag producing area of ​​the entire tunnel face.

12. The step method one-time excavation construction method as claimed in claim 1, characterized in that: The conveying part discharges the slag from the bottom of the stand; or discharges the slag from at least one side of the stand; or discharges the slag from the bottom of the stand first, and then passes through the stand to discharge the slag from at least one side of the stand.

13. The step method one-time excavation construction method as claimed in claim 4, characterized in that: The upper step shotcreting operation includes the initial shotcreting operation. Specifically, a storage device is provided at the rear end of the platform, and an upper step shotcreting assembly is provided on the step. The upper step shotcreting assembly is connected to the storage device. The initial shotcreting operation is carried out toward the excavation area of ​​the face through the upper step shotcreting assembly.

14. The step method one-time excavation construction method as claimed in claim 4, characterized in that: The upper step erection and anchor bolting operations are specifically as follows: arch anchor arms that can move along the length direction of the frame are set on both sides and the top of the frame; the arch frame is transported and erected by the arch anchor arms, and after the erection operation is completed, the anchor bolt anchoring operation is carried out by the anchor arch arms; the upper step shotcreting operation includes re-spraying operation, specifically, the upper step shotcreting assembly is used to re-spray the assembled arch frames on both sides of the tunnel.

15. The step method one-time excavation construction method as claimed in claim 7, characterized in that: The slag turning operation at the lower step is specifically to transport the slag away from the area where the invert arch is to be erected by a loader, pile a part of the slag on the side of the area where the invert arch is to be erected, and transport the remaining slag away from the tunnel.

16. The step method one-time excavation construction method as claimed in claim 7, characterized in that: The lower step erection operation is specifically as follows: an inverted arch transport assembly is provided at the rear end of the platform, the inverted arch is transported to a predetermined position by the inverted arch transport assembly, and the construction personnel dock and lock the inverted arch with the upper arch frame to complete the erection operation of the inverted arch.

17. The step method one-time excavation construction method according to claim 7, characterized in that: The anchor bolting and shotcreting operations of the lower step are specifically as follows: a hanging arch anchor arm is provided at the rear end of the gantry, and the locking foot anchor bolt operation is performed on the inverted arch through the hanging arch anchor arm, and / or the system anchor bolt operation is performed on the inverted arch in the specified area according to the specifications; the shotcreting operation of the lower step is to perform shotcreting operation on the assembled and fixed inverted arch through the lower step shotcrete assembly.

18. The step method one-time excavation construction method as claimed in claim 1, characterized in that: The specific steps include: Step 1: Carry out upper step excavation work at the upper step; Step 2: After the excavation work of the upper step is completed, the upper step slag removal work is carried out, and at the same time, the upper step arch frame transfer work is carried out in the upper step construction area; at this time, the lower step excavation work is carried out at the lower step; Step 3: After the upper step arch frame transfer operation is completed, the upper step frame erection operation is carried out, and at the same time, the upper step slag removal operation is continued according to the actual slag material conditions on site; at this time, the lower step slag turning operation is carried out; before the upper step frame erection operation, the unit needs to be moved and the excavation unit needs to slide to the tunnel face for the next cycle of upper step excavation operation; Step 4: After the upper stage erection work is completed, the upper step mesh welding work and the upper step locking foot anchor work are carried out at the arch frame; at this time, the lower step erection work and the invert arch cleaning work are carried out at the lower step; Step 5: After the locking foot anchoring operation of the upper step is completed, the leading anchoring operation and the system anchoring operation of the upper step are carried out; at this time, the locking foot anchoring operation of the lower step, the erection operation of the lower step invert arch, the lower step spraying operation and the invert arch re-spraying operation are carried out at the lower step; Step 6: After the upper step anchoring operation is completed, the upper step spraying operation is carried out. At this time, the spraying position is located at the bottom of both sides of the arch frame. At this time, the lower step performs the invert backfill operation; Step seven: After the grouting operation of the lower part of the upper step is completed, the grouting operation of the remaining parts of the upper step is carried out, and the next cycle of upper step excavation operation is carried out simultaneously.

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