Tunnel construction method

Abstract

The present invention provides a tunnel construction method, which includes collecting environmental information of the tunnel, measuring the length of the open hole of the tunnel; setting a retaining wall on one side of the biased slope of the tunnel according to the environmental information and the length of the open hole; backfilling the retaining wall toward the side of the biased slope of the tunnel according to the environmental information, until the height of 1 / 2 of the top of the slope of the tunnel; and excavating the tunnel according to the environmental information. The technical solution of the present invention measures the environmental information of the tunnel before the tunnel construction, sets the retaining wall according to the tunnel information, and implements backfilling and reinforcement of the biased slope of the tunnel by slope release, so as to prevent the high and steep side slope from sliding and collapsing in the tunnel construction excavation in the soft rock geology such as the collapse of the railway and highway tunnels, and the shallow buried biased slope environment, thereby improving the safety of construction.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel engineering construction, and in particular to a tunnel construction method. Background Art

[0002] The collapse and accumulation characteristics of landslide accretion bodies often cause engineering construction to become unstable. At home and abroad, the main methods of controlled blasting excavation are used for landslide accretion body geological tunnels; active reinforcement methods such as pipe pile grouting; and passive protection measures such as retaining walls and anti-slide piles. However, for landslide accretion body geology, there are certain limitations to the construction conditions of tunnels passing under high and steep slopes, which led to the collapse of high and steep slopes in the early excavation; and the overall settlement of the top road and residential houses. Summary of the invention

[0003] The main purpose of the present invention is to provide a tunnel construction method, aiming to solve the technical problems in the prior art of tunnel construction and excavation, such as high and steep side slope collapse, overall settlement of the slope top road and residential houses, and other dangerous situations.

[0004] To achieve the above object, the present invention proposes a tunnel construction method, which comprises:

[0005] Collecting environmental information of the tunnel and measuring the open hole length of the tunnel;

[0006] According to the environmental information and the length of the open tunnel, a retaining wall is set on the side of the slope where the tunnel is biased;

[0007] According to the environmental information, backfilling is performed on the side of the slope of the retaining wall that is biased toward the tunnel, until the height reaches 1 / 2 of the top of the slope of the tunnel;

[0008] The tunnel is excavated and constructed according to the environmental information.

[0009] Optionally, after collecting the environmental information of the tunnel and measuring the open hole length of the tunnel, the method further includes:

[0010] The biased side slope of the tunnel and the upward slope of the tunnel are preprocessed according to the environmental information.

[0011] Optionally, the step of preprocessing the biased slope of the tunnel and the upward slope of the tunnel according to the environmental information includes:

[0012] A waterproof layer is laid in the road influence range at the top of the tunnel, and drainage holes are opened in the upper slope of the tunnel;

[0013] Reinforcement piles are arranged in the tunnel.

[0014] Optionally, the step of collecting tunnel environment information includes:

[0015] Obtaining the length of the dark hole of the tunnel and the position of the end wall of the tunnel;

[0016] According to the environmental information and the length of the open tunnel, the step of setting a retaining wall on one side of the biased slope of the tunnel comprises:

[0017] According to the length of the blind hole and the length of the open hole, the retaining wall is arranged from the end wall along the end wall toward the slope of the tunnel;

[0018] A drainage pipe is pre-buried in the retaining wall, and the drainage pipe is extended to the outside of the retaining wall.

[0019] Optionally, after the step of arranging the retaining wall along the direction of the end wall toward the biased slope of the tunnel, the method further comprises:

[0020] measuring the angle between the end wall and the retaining wall;

[0021] comparing the angle with a preset angle;

[0022] When the difference between the included angle and the preset included angle is greater than the preset difference, the position of the retaining wall is adjusted so that the difference is less than or equal to the preset difference.

[0023] Optionally, after the step of arranging the retaining wall along the slope direction of the end wall biased toward the tunnel, the method further comprises:

[0024] Measuring the slopes of the sides of the retaining wall;

[0025] When the wall slope of the retaining wall does not meet the standard slope, the slope is adjusted until it is equal to the standard slope.

[0026] Optionally, after the step of arranging the retaining wall along the slope direction of the end wall biased toward the tunnel, the method further comprises:

[0027] A water intercepting ditch is arranged on one side of the end wall, and the drainage pipe is connected to the water intercepting ditch.

[0028] Optionally, the step of collecting tunnel environment information includes:

[0029] Measuring the cross section of the slope of the tunnel at every preset interval;

[0030] Obtaining the minimum buried depth of the tunnel between two adjacent cross sections to provide a design basis for backfilling under counterpressure;

[0031] The step of backfilling the side slope of the retaining wall biased toward the tunnel according to the environmental information until the top of the tunnel comprises:

[0032] The backfill design is carried out according to the minimum buried depth of the tunnel, and the backfill is carried out on the side of the slope of the retaining wall which is biased toward the tunnel, until the height reaches 1 / 2 of the top of the slope of the tunnel.

[0033] Optionally, after the step of designing and implementing the retaining wall and backfilling for counter-pressure backfilling toward the side of the slope biased toward the tunnel by the retaining wall according to the minimum buried depth of the tunnel until the height of 1 / 2 of the top of the slope of the tunnel, the step further includes:

[0034] Get the compaction degree after backfilling by back pressure;

[0035] When the compaction degree is less than a preset compaction degree, backfill is back-pressed toward one side of the slope of the tunnel toward the retaining wall and further layered rolling is performed until the compaction degree reaches the preset compaction degree.

[0036] Optionally, the step of performing excavation construction in the tunnel according to the environmental information includes:

[0037] obtaining the rock type in the tunnel;

[0038] Adjusting the digging tool to the rock type;

[0039] The base of the tunnel is reinforced by grouting.

[0040] The technical solution of the present invention measures the environmental information of the tunnel before tunnel construction, sets the retaining wall according to the tunnel information, and implements slope reduction and soil and rock backfill reinforcement on the tunnel slope, thereby preventing the high and steep side slopes from sliding during tunnel construction in the soft rock geology such as railway and highway tunnel collapse and shallow buried bias pressure environment, thereby improving the safety of construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0042] Figure 1 It is a schematic diagram of the process of the first embodiment of the tunnel construction method of the present invention;

[0043] Figure 2 It is a schematic diagram of the flow chart of the second embodiment of the tunnel construction method of the present invention;

[0044] Figure 3 It is a schematic diagram of the process of the third embodiment of the tunnel construction method of the present invention;

[0045] Figure 4 It is a schematic diagram of the flow chart of the fourth embodiment of the tunnel construction method of the present invention;

[0046] Figure 5 It is a schematic flow chart of the fifth embodiment of the tunnel construction method according to the present invention.

[0047] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0050] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0051] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0053] The present invention proposes a tunnel construction method, please refer to Figure 1 , Figure 1 This is a schematic diagram of the process of the first embodiment of the tunnel construction method of the present invention, which specifically includes the following steps:

[0054] Step S10: collecting environmental information of the tunnel and measuring the open hole length of the tunnel;

[0055] Step S20: According to the environmental information and the length of the open tunnel, a retaining wall is set on one side of the slope where the tunnel is biased;

[0056] Step S30: backfilling the side of the slope of the retaining wall that is biased toward the tunnel according to the environmental information until it reaches 1 / 2 of the height of the top of the slope of the tunnel;

[0057] Step S40: excavating the tunnel according to the environmental information.

[0058] Before construction, the environment of the tunnel is measured to obtain the environmental information. Specifically, the environmental information may include but is not limited to rock type, dark hole length, open hole length, side slope rate, back slope rate, etc. In addition, after step S10, the side slope and back slope of the tunnel may be preprocessed according to the environmental information. Specifically, the following steps are included:

[0059] Step S51: laying a waterproof layer on the top of the tunnel slope, and opening drainage holes on the upper slope of the tunnel;

[0060] Step S52: Setting reinforcement piles in the tunnel.

[0061] When there are buildings on the top of the slope of the tunnel, it is necessary to provide transitional resettlement for the affected residents, and at the same time, strengthen monitoring and measurement of the houses and the surrounding areas. The top of the slope of the tunnel is protected. Through measurement, a suitable location is selected, such as the houses and roads on the top of the slope of the tunnel, which are not less than 20m from the top and edge of the tunnel, and the surface is covered with a waterproof layer to prevent rainwater from seeping in. After that, the slope of the tunnel is protected, and the drainage holes are opened on the back slope of the tunnel entrance close to the side slope or the side slope and the back slope are combined with the terrain to facilitate the removal of pore water during the subsequent construction process. Finally, the back slope of the tunnel is protected and reinforced. It can be understood that in the construction of the tunnel, there are usually two lines, left and right, namely the left tunnel and the right tunnel. Among them, the lengths of the open holes of the left tunnel and the right tunnel can be different, for example, the length of the left line open hole is 10m, and the length of the right line open hole is 17m; during construction, the open hole and end wall type tunnel door should be constructed as soon as possible; and 3 2×1.5m reinforcement piles are set in the left and right tunnels respectively, and the length of a single reinforcement pile varies from 20 to 26m.

[0062] After the pretreatment is completed, the retaining wall is set on the left and right sides of the hole respectively. The retaining wall is 10m high and the foundation is buried at a depth of not less than 1.5m. The top of the retaining wall should be flush with the ground line. Specifically, step S10 specifically includes:

[0063] Step S11: obtaining the length of the dark hole of the tunnel and the position of the end wall of the tunnel;

[0064] Step S20 specifically includes:

[0065] Step S21: according to the length of the blind hole and the length of the open hole, the retaining wall is arranged from the end wall along the direction of the end wall toward the slope of the tunnel;

[0066] Step S22: pre-burying a drainage pipe in the retaining wall, and extending the drainage pipe to the outside of the retaining wall.

[0067] First, determine the construction position of the retaining wall. Specifically, the retaining wall can be used as the starting point of the end wall of the tunnel and extend along the edge of the tunnel. Before construction, the construction position of the retaining wall is marked and cleared; the buried depth of the retaining wall is not less than 1.5m, and the drainage pipe is pre-buried in the wall of the retaining wall to drain the accumulated water behind the retaining wall.

[0068] It should be noted that the drainage holes are arranged in layers on the retaining wall body above the ground. The spacing between the drainage holes can be set within the range of 2m to 3m and arranged in a plum blossom shape. Φ100 PVC pipes are pre-buried in the drainage holes. The UPVC pipes are 20cm longer and the ends 30cm of them are wrapped with geotextile. The bottom row of drainage holes is more than 100cm above the ground. A crushed stone filter layer with a thickness of not less than 30cm is set at the water inlet of the drainage holes to facilitate drainage.

[0069] The technical solution of the present invention measures the environmental information of the tunnel before tunnel construction, sets the retaining wall according to the tunnel information, and implements slope reduction and soil and rock backfill reinforcement on the tunnel slope, thereby preventing the high and steep side slopes from sliding during tunnel construction in the soft rock geology such as railway and highway tunnel collapse and shallow buried bias pressure environment, thereby improving the safety of construction.

[0070] For details, please refer to Figure 2 , Figure 2 This is a flow chart of the second embodiment of the tunnel construction method of the present invention. After step S21, the method further includes:

[0071] Step S23: measuring the angle between the end wall and the retaining wall;

[0072] Step S24: comparing the angle with a preset angle;

[0073] Step S25: When the difference between the included angle and the preset included angle is greater than the preset difference, adjusting the position of the retaining wall so that the difference is less than or equal to the preset difference.

[0074] After step S21, the method further includes:

[0075] Step S26: measuring the slopes of the sides of the retaining wall;

[0076] Step S27: When the slope does not meet the standard slope, adjust the slope until it is equal to the standard slope.

[0077] In this embodiment, starting from the end wall of the tunnel, the right tunnel of the tunnel is taken as an example. The open hole length of the right tunnel is 17m, and the length of the back pressure backfill section is 68m in total, so the total length of the retaining wall is set to 85m. Among them, there is a certain angle between the end wall of the right tunnel of the tunnel and the retaining wall. Preferably, the angle can be selected to be about 60°. When pouring the retaining wall, the angle between the retaining wall and the end wall is measured. In the actual construction process, there is a certain error in the angle, and it is only necessary to ensure that the error is within the preset difference range. When the error exceeds the preset difference range, it is necessary to adjust the position of the retaining wall to ensure the safe construction.

[0078] The height of the retaining wall can be set to 10m, and the other wall heights are 2 to 8m depending on the terrain; the side wall slope ratio of the standard section of the retaining wall, that is, the standard slope rate is 1:0.3, that is, the standard section of the retaining wall is approximately trapezoidal, wherein the top width of the retaining wall can be set to 1m, and the bottom width can be set to 7.2m. According to the formula, it can be calculated that the retaining wall is 41m in total 2 , the height of the remaining sections varies according to the terrain, and the top width of 1m and the slope ratio of 1:0.3 are kept unchanged. Similarly, during the construction process, the slope of the retaining wall is measured. When the slope is greater than or less than the standard slope, the retaining wall should be adjusted in time.

[0079] After step S21, the method further includes:

[0080] Step S28: a drainage ditch is provided on one side of the end wall, and the drainage pipe is connected to the drainage ditch.

[0081] The intercepting ditch is made of M10 mortar-laid flagstones to ensure smooth drainage around the backfill body during construction.

[0082] For details, please refer to Figure 3 , Figure 3 This is a schematic flow chart of the third embodiment of the tunnel construction method of the present invention, wherein step S10 specifically includes:

[0083] Step S12: measuring the cross section of the slope of the tunnel once at a preset distance;

[0084] Step S13: obtaining the minimum buried depth of the tunnel between two adjacent cross sections to provide a design basis for backfilling under counterpressure;

[0085] Step S30 includes:

[0086] Step S31: designing the backfill according to the minimum buried depth of the tunnel, and backfilling the side of the slope of the retaining wall biased toward the tunnel until it reaches 1 / 2 of the height of the top of the slope of the tunnel.

[0087] The cross section is measured once after each preset distance along the line direction of the tunnel. The preset distance can be selected as 10m. Taking the right tunnel of the tunnel as an example, the slope cross section on the right side of the right tunnel is measured. It can be understood that after the measurement, the cross section can be automatically generated by software mapping, and the minimum buried depth of the tunnel is obtained after each measurement. Among them, the minimum buried depth of the entire tunnel is 20m from the right tunnel entrance, which is only 2.48m. Please refer to Table 1 for details.

[0088] Table 1:

[0089]

[0090] After the measurement is completed, according to the minimum buried depth of the tunnel, it is proved that the right side of the right hole of the tunnel is significantly biased, which provides sufficient design basis for the backfilling with counter pressure.

[0091] For further information, please refer to Figure 4 , Figure 4 This is a flow chart of a fourth embodiment of the tunnel construction method of the present invention. After step S31, the method further includes:

[0092] Step S32: obtaining the compaction degree after backfilling by back pressure;

[0093] Step S33: When the compaction degree is less than the preset compaction degree, backfilling is further performed in layers toward the side of the slope of the retaining wall facing the tunnel, until the compaction degree reaches the preset compaction degree.

[0094] In this embodiment, the backfill of the right tunnel of the tunnel is taken as an example to illustrate. The backfill is constructed from the right tunnel entrance to the intersection of the wall top and the ground line. The bottom of the inner side of the retaining wall (that is, the side facing the slope) is filled with dry-laid stone slabs, and the rest of the area is backfilled with rammed earth and stone. The compaction degree is not less than 85%; the top elevation of the backfill body is 418m, up to about 1 / 2 of the height of the top of the slope of the tunnel. The backfill slope is evenly transitioned according to the on-site terrain, and 50cm thick cultivated soil is used on the top; the backfill is layered, and the layer level and top surface must have a slope of at least 2% to facilitate drainage. The backfill area is about 21,000 m 3 .

[0095] For further information, please refer to Figure 5 , Figure 5 This is a schematic flow chart of the fifth embodiment of the tunnel construction method of the present invention, step S40 includes:

[0096] Step S41: obtaining the rock type in the tunnel;

[0097] Step S42: adjusting the excavation tool according to the rock type;

[0098] Step S43: Grouting reinforcement of the base of the tunnel.

[0099] A long Large pipe shed, used in the cave Middle pipe shed, auxiliary A small advance guide tube is used; after obtaining the rock type in the tunnel, a breaker hammer is used for the V-level surrounding rock and a milling machine is used for the IV-level surrounding rock, and a three-step temporary invert excavation scheme is used; according to the design requirements, grouting reinforcement such as steel pipe piles is implemented on the tunnel base; and a reinforced secondary lining is used for the section under the collapsed slope accumulation body. This improves the safety of the construction.

[0100] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A tunnel construction method, It is characterized in that The tunnel construction method comprises: Collecting environmental information of the tunnel and measuring the length of the open hole of the tunnel, wherein collecting the environmental information specifically includes obtaining the length of the dark hole of the tunnel and the position of the end wall of the tunnel; Measuring the cross section of the slope of the tunnel at every preset interval; Obtaining the minimum buried depth of the tunnel between two adjacent cross sections to provide a design basis for backfilling under counterpressure; According to the length of the dark tunnel and the length of the open tunnel, a retaining wall is arranged from the end wall along the slope direction of the end wall toward the tunnel bias; Pre-buried drainage pipes in the retaining wall, and extending the drainage pipes to the outside of the retaining wall; measuring the angle between the end wall and the retaining wall; comparing the angle with a preset angle; When the difference between the included angle and the preset included angle is greater than the preset difference, the position of the retaining wall is adjusted so that the difference is less than or equal to the preset difference; Measuring the slopes of the sides of the retaining wall; When the wall slope of the retaining wall does not meet the standard slope, adjusting the slope until it is equal to the standard slope; Backfill design is performed according to the minimum buried depth of the tunnel, and the backfill is performed on the side of the slope of the retaining wall that is biased toward the tunnel, until the height reaches 1 / 2 of the top of the slope of the tunnel; The tunnel is excavated and constructed according to the environmental information.

2. The tunnel construction method according to claim 1, It is characterized in that After collecting the environmental information of the tunnel and measuring the open hole length of the tunnel, the method further includes: The biased side slope of the tunnel and the upward slope of the tunnel are preprocessed according to the environmental information.

3. The tunnel construction method according to claim 2, It is characterized in that The step of preprocessing the biased side slope of the tunnel and the upward slope of the tunnel according to the environmental information comprises: Laying a waterproof layer on the top of the tunnel slope, and opening drainage holes on the upper slope of the tunnel; Reinforcement piles are arranged in the tunnel.

4. The tunnel construction method according to claim 1, It is characterized in that After the step of arranging the retaining wall along the slope direction of the end wall biased toward the tunnel, the method further comprises: A water intercepting ditch is arranged on one side of the end wall, and the drainage pipe is connected to the water intercepting ditch.

5. The tunnel construction method according to claim 1, It is characterized in that According to the minimum buried depth of the tunnel, after the step of designing and implementing the retaining wall and backfilling of the retaining wall toward the side of the slope biased toward the tunnel until the height of 1 / 2 of the top of the slope of the tunnel, the method further includes: Get the compaction degree after backfilling by back pressure; When the compaction degree is less than a preset compaction degree, backfill is back-pressed toward one side of the slope of the tunnel toward the retaining wall and further layered rolling is performed until the compaction degree reaches the preset compaction degree.

6. The tunnel construction method according to any one of claims 1 to 5, It is characterized in that The step of performing excavation construction in the tunnel according to the environmental information comprises: obtaining the rock type in the tunnel; Adjusting the digging tool to the rock type; The base of the tunnel is reinforced by grouting.

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