CN111828050B - A construction method for a small-section traffic tunnel entering a diversion lock chamber with a thin, tall and special-shaped space structure - Google Patents

Abstract

The invention relates to the technical field of building construction, in particular to a construction method for a small-section traffic hole entering a diversion lock chamber with a thin, tall and special-shaped space structure. Do initial support for the vault and side walls; Step 2, construction of the lock chamber: construct the lock chamber by lifting the roof in the transition section, and perform initial support for the vault and side walls of the lock chamber. Construction by layered and block method; Step 3, excavate the branch trunk: horizontally lift and excavate the branch trunk, so that the branch trunk runs through the lower part of the lock chamber. During the construction process, the entire sluice chamber is divided into upper, middle and lower areas for excavation. The upper part of the sluice chamber is constructed by the step method, and the middle part of the sluice chamber is excavated by the layered and block method. , the excavation process has little influence on the stability of the surrounding tunnel structure, avoids the risk of construction collapse of the thin, tall and special-shaped complex space structure, and improves the safety during the construction process.

Description

A construction method for a small-section traffic tunnel entering a diversion lock chamber with a thin, tall and special-shaped space structure

technical field

The invention relates to the technical field of building construction, in particular to a construction method for a small-section traffic hole entering a diversion lock chamber with a thin, high and special-shaped space structure.

Background technique

With the rapid development of water diversion engineering construction, many water diversion tunnels pass through complex geology. Generally, water diversion tunnels are long in length and small in cross section. At the intersection of main trunk and branch trunk, it is usually necessary to set up an intake lock chamber to realize diversion. It is necessary to set up a transition section at the Sanchakou. The main trunk enters the transition section and then enters each branch in turn. The intake lock chamber has a higher structural section height than the diversion tunnel due to equipment installation requirements. The lock chamber at the Sanchakou connects the transition section and the branch at the same time. , the construction is difficult, the traditional method is to use the transition section to lift into the sluice chamber, and then carry out the expansion and excavation construction, that is, first excavate the prototype of the sluice chamber, and then gradually expand the sluice chamber to the surrounding area to reach the preset size, so that the sluice chamber is fully excavated. The inner contour has been in a state of change during the construction process, which is inconvenient for the support and erection of the sluice chamber. At the same time, the expansion and excavation construction will have a certain degree of shock to the entire sluice chamber, which is likely to cause collapse accidents.

Therefore, there is currently a need for a technical solution to solve the technical problem that collapse accidents are prone to occur during the construction of the lock chamber after the transition section enters the lock chamber during the construction of the three forks of the diversion tunnel in the prior art.

SUMMARY OF THE INVENTION

The purpose of the invention of the present invention is to: aiming at the technical problem that collapse accidents are prone to occur during the construction of the lock chamber after entering the lock chamber from the transition section during the construction of the three-way entrance of the diversion tunnel in the prior art, to provide a small-section traffic tunnel entrance Construction method of diversion lock chamber with thin and tall special-shaped space structure.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A construction method for a small-section traffic hole entering a diversion lock chamber with a thin, tall and special-shaped space structure, the steps of which are as follows:

Step 1, construction transition section: the main trunk canopy construction transition section, and initial support for the vault and side walls of the transition section;

Step 2, construction of the sluice chamber: the construction of the sluice chamber is carried out by lifting the roof in the transition section, and the initial support for the dome and side walls of the sluice chamber is carried out.

Step 3, excavate the branch trunk: excavate the branch trunk horizontally, so that the branch trunk runs through the lower part of the lock chamber.

The invention provides a construction method for a small-section traffic tunnel entering a diversion lock chamber with a thin, high and special-shaped space structure. During the construction process, initial support is performed on the position of the vault side wall of the tunnel to strengthen the structural strength of the water diversion tunnel. The transition section is lifted into the upper part of the lock chamber, and the entire lock chamber is divided into upper, middle and lower areas to be excavated respectively. The upper part of the lock chamber is constructed by the step method, which is gradually excavated from top to bottom, and the middle part of the lock chamber is divided into layers and blocks. The middle of the lock chamber is divided into several layers in the height direction, and the middle part of the lock chamber is divided into several blocks in each layer, so that the excavation has less influence on the stability of the surrounding tunnel structure, and it is also convenient to observe the characteristics of each layer, The geological conditions of each block are convenient for preventing emergencies and improving the safety during construction. Insufficient strength, resulting in the collapse of the lock chamber and other phenomena.

As a preferred solution of the present invention, the step 1 further includes step 1.1, optimizing the shape of the transition section: the transition section is provided with a plurality of sluice chamber interfaces, and the axis of the sluice chamber interface is perpendicular to the side wall of the sluice chamber. Therefore, it is not necessary to convert the face during the process of entering the lock chamber in the transition section, which improves the construction efficiency.

As a preferred solution of the present invention, the initial support includes spraying concrete on the vault and side walls, and installing several support frames. The tunnel is reinforced by spraying concrete on the vault and side walls of the tunnel, and at the same time, a support frame is installed in the tunnel to support the vault and side walls, so that the tunnel can maintain sufficient strength during the construction process to withstand the construction process. The destructive force caused by various construction operations.

As a preferred solution of the present invention, the support frame includes an arc-shaped rod adapted to the shape of the dome, and two ends of the arc-shaped rod are respectively provided with uprights. The arc-shaped rod and the two uprights are connected to form a gate-shaped structure, so that the support frame can abut against the vault and side wall of the tunnel after being installed in the tunnel, thereby forming support for the vault and side wall of the tunnel.

As a preferred solution of the present invention, the layered block method includes: firstly dividing the middle of the lock chamber into several excavation layers along the height direction of the lock chamber, then dividing each excavation layer into several excavation blocks, and selecting one excavation block Excavate, and then excavate other excavation blocks in sequence, and the height of each excavation is the same as the height of the excavation layer.

As a preferred solution of the present invention, for several excavation blocks of each layer, the first excavated excavation block is blasted with vertical shallow hole, and the other excavated blocks are blasted with pre-split blasting. Among them, vertical shallow-hole blasting refers to setting blasting holes at the upper end of the blasting area for blasting, pre-splitting blasting refers to setting blasting holes on the side wall of the blasting area for blasting, and performing vertical shallow-hole blasting at an excavation block on an excavation layer After forming a step, pre-split blasting is performed on other excavated blocks of the excavation layer, which reduces the disturbance of the blasting to the surrounding wall of the tunnel and improves the safety of the construction process.

As a preferred solution of the present invention, in the step 2, after the construction in the middle of the sluice chamber is completed, a grouting hole is opened on the side wall of the middle part of the sluice chamber, and a grouting anchor pipe is arranged in the grouting hole. The grout is injected into the rock formation through the grouting hole on the side wall in the middle of the sluice chamber to improve the structural strength of the surrounding wall of the tunnel and prepare for the construction of the lower part of the sluice chamber.

As a preferred solution of the present invention, the grouting holes are arranged obliquely downward. The grout is transported to the lower part of the sluice chamber through the grouting holes set obliquely downward, so that the surrounding rock formations in the lower part of the sluice chamber are strengthened, and the safety of blasting construction in the lower part of the sluice chamber is ensured.

As a preferred solution of the present invention, in the step 3, when the branch trunk enters the lower part of the sluice chamber, the bottom plate, side wall, and vault of the branch trunk are all constructed by blasting with enlarged external angle. Among them, blasting with enlarged outside angle means that when the branch trunk enters the sluice chamber, blasting holes are set on the peripheral wall of the tunnel obliquely outside the tunnel for blasting. The distance between the side walls is larger, and the bottom of the sluice chamber is also lower than the bottom of the branch trunk. Therefore, blasting at the enlarged outer angle for construction can reduce the later correction work and improve the construction efficiency.

As a preferred solution of the present invention, in the step 3, in the process of excavation, when entering the lower part of the sluice chamber from the branch trunk, manual trimming is used for the sudden change of the clearance between the branch trunk and the sluice chamber. Among them, the sudden change of clearance refers to the junction of the branch trunk and the lock chamber. The construction volume at the sudden change of clearance is small, and it is difficult to use large-scale equipment and blasting for construction. The use of manual trimming construction can improve the construction accuracy and help ensure construction safety.

As a preferred solution of the present invention, in the step 3, a connecting rod is arranged at the bottom of the support trunk, and the connecting rod is detachably connected to the support frame in the lock chamber. Specifically, the bottom of each support frame is provided with a cross bar, the two ends of the cross bar are respectively connected with the two upright columns, and the connecting bar and the cross bar are detachably connected. The support frames arranged in the upper part and the middle part of the lock chamber form a stable support, two connecting rods are arranged under each support frame, and the two connecting rods are respectively arranged on both sides of the lock chamber.

To sum up, due to the adoption of the above-mentioned technical solutions, the beneficial effects of the present invention are:

The invention provides a construction method for a small-section traffic tunnel entering a diversion lock chamber with a thin, high and special-shaped space structure. During the construction process, initial support is performed on the position of the vault side wall of the tunnel to strengthen the structural strength of the water diversion tunnel. The transition section is lifted into the upper part of the lock chamber, and the entire lock chamber is divided into upper, middle and lower areas to be excavated respectively. The upper part of the lock chamber is constructed by the step method, which is gradually excavated from top to bottom, and the middle part of the lock chamber is divided into layers and blocks. The middle of the lock chamber is divided into several layers in the height direction, and the middle part of the lock chamber is divided into several blocks in each layer, so that the excavation has less influence on the stability of the surrounding tunnel structure, and it is also convenient to observe the characteristics of each layer, The geological conditions of each block are convenient for preventing emergencies and improving the safety during construction. Insufficient, resulting in the collapse of the lock chamber and other phenomena.

Description of drawings

Fig. 1 is the construction flow chart of a kind of construction method of the present invention that a small-section traffic tunnel enters a diversion lock chamber with a thin, high and special-shaped space structure;

Fig. 2 is the layout diagram of trunk, branch trunk, transition section and lock chamber according to the present invention;

Fig. 3 is the positional relationship diagram of the lock chamber and the branch trunk according to the present invention;

4 is a schematic diagram of the layered and block construction according to the present invention;

Fig. 5 is the structural schematic diagram of the support frame of the present invention;

Fig. 6 is the construction schematic diagram of step 3 of the invention;

Marked in the figure: 1- main trunk, 2- branch trunk, 3- lock chamber, 31- excavation layer, 311- excavation fast, 4- transition section, 41- lock chamber interface, 5- support frame, 51- arc rod, 52-column, 53-crossbar, 54-connecting rod, 6-blasting hole.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings.

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

Example 1

As shown in Fig. 1-Fig. 6, a construction method of a small-section traffic hole entering a diversion lock chamber with a thin, tall and special-shaped space structure of the present invention, the steps are as follows:

Step 1.1, optimize the shape of the transition section: the transition section 4 is provided with a number of lock chamber interfaces 41, and the axis of the lock chamber interface 41 is set perpendicular to the side wall of the lock chamber 3, so that in the process of the transition section 4 entering the lock chamber 3 There is also no need to convert the palm face, which improves the construction efficiency.

Step 1, construction transition section: trunk 1 lifts the roof to construct transition section 4, trunk 1 is lifted step by step into the transition section, and the vault and side walls of transition section 4 are initially supported. Transition section 4 is higher than trunk 1, and the trunk 1. After the roof is lifted into the elevation position of the transition section 4, the transition section is excavated by the step method. The step method is to layer the area to be excavated into several layers and excavate sequentially from top to bottom, in which the trunk 1 is lifted step by step and enters the transition section. , to avoid damaging the design shape of the transition section 4, thereby avoiding the need for concrete backfilling of the transition section 4 caused by excessive excavation;

Step 2, construction of the lock chamber: the transition section 4 is lifted from the roof to construct the lock chamber 3, and the transition section 4 is lifted into the lock chamber 3 step by step, and the vault and side walls of the lock chamber 3 are initially supported. The upper part of the lock chamber 3 adopts the step method During the construction, the middle part of the lock chamber 3 is constructed by the layered and block method, and the transition section 4 is lifted into the lock chamber 3 step by step, so as to avoid damaging the design shape of the lock chamber 3, thus avoiding the need for the lock chamber 3 due to excessive excavation. Concrete backfill;

Step 3, excavate the branch trunk: horizontally lift and excavate the branch trunk 2, so that the branch trunk 2 passes through the lower part of the lock chamber 3.

Specifically, the initial support includes spraying concrete on the vault and side walls, and installing a number of support frames 5, which are evenly arranged along the length of the tunnel, by spraying concrete on the vault and side walls of the tunnel Reinforce the tunnel, spray C20 concrete on the vault and side wall of transition section 4 and lock chamber 3, with a thickness of 20cm, and install support frame 5 in the tunnel to support the vault and side wall, so that the tunnel can be constructed during the construction process. It can maintain sufficient strength to withstand the destructive force caused by various construction operations during the construction process, wherein the support frame 5 includes an arc-shaped rod 51 that is adapted to the shape of the dome, and the two ends of the arc-shaped rod 51 are respectively provided. There are uprights 52, and the arc-shaped rod 51 and the two uprights 51 are connected to form a gate-shaped structure, so that the support frame 5 can abut against the vault and side walls of the tunnel after being installed in the tunnel, thereby forming the vault and side walls of the tunnel. support;

The layered and block method includes: first, dividing the middle of the lock chamber 4 into several excavation layers 31 along the height direction of the lock chamber 4, and then dividing each excavation layer 31 into a number of excavation blocks 311, and selecting one excavation block 311 to carry out the process. Excavate, and then excavate the other excavation blocks 311 in sequence, and the height of each excavation is the same as the height of the excavation layer 31, so that each construction has less impact on the structure around the lock chamber, and it is also convenient to observe each excavation block 311, each The geological conditions of the first excavation layer 31 can prevent emergencies. For several excavation blocks 311 in each layer, the first excavated excavation block 311 is blasted with vertical shallow holes, and the other excavated blocks are blasted with pre-split blasting. Among them, vertical shallow hole blasting refers to setting blasting holes at the upper end of the blasting area for blasting, pre-split blasting refers to setting blasting holes on the side wall of the blasting area for blasting, and performing vertical shallow blasting at an excavation block 311 on an excavation layer 31 After the eye is blasted, a step is formed, and then the other excavation blocks 311 of the excavation layer 31 are pre-split and blasted, which reduces the disturbance of the blasting to the surrounding wall of the tunnel and improves the safety of the construction process.

Further, in the step 2, after the construction in the middle part of the lock chamber 3 is completed, a grouting hole is opened on the side wall of the middle part of the lock chamber 3, and a grouting anchor pipe is set in the grouting hole, passing through the middle part of the lock chamber 3. The grouting holes on the side walls pour grout into the rock formation to improve the structural strength of the surrounding wall of the tunnel and prepare for the construction of the lower part of the sluice chamber 3. Further, the grouting holes are set obliquely downward. The grouting hole in the sluice chamber transports the slurry to the lower part of the sluice chamber, so that the surrounding rock formations in the lower part of the sluice chamber are strengthened, and the safety of blasting construction in the lower part of the sluice chamber is ensured.

Further, in the step 3, in the construction of the lower part of the support stem 2 entering the lock chamber 3, the support stem bottom plate, the side wall, and the vault are all constructed by using magnified outside angle blasting, wherein the enlarged outside insert angle blasting refers to the construction. When the branch trunk 2 enters the lock chamber 3, blasting holes 6 are set on the peripheral wall of the tunnel obliquely to the outside of the tunnel for blasting. It is larger and the bottom of the lock chamber 3 is also lower than the bottom of the branch trunk 2, so the use of enlarged external angle blasting for construction can reduce the later correction work and improve the construction efficiency.

Further, in the step 3, in the process of excavation, when entering the lower part of the lock chamber 3 from the branch trunk 2, manual trimming is adopted at the sudden change of clearance between the branch trunk 2 and the lock chamber 3, wherein the sudden change of clearance refers to the branch trunk 2. At the junction with lock chamber 3, the construction volume at the sudden change of clearance is small, and it is difficult to use large-scale equipment and blasting for construction. The use of manual trimming construction can improve construction accuracy and help ensure construction safety.

Further, in the step 3, a connecting rod 54 is provided at the bottom of the support trunk 2, and the connecting rod 54 is detachably connected with the support frame 5 in the lock chamber 3. Specifically, the bottom of each support frame 5 is provided with There is a cross bar 53, the two ends of the cross bar 53 are respectively connected with the two uprights 52, and the connecting bar 54 is detachably connected with the cross bar 53. The supporting frame 5 arranged in the middle forms a stable support, and two connecting rods 54 are arranged under each supporting frame 5, and the two connecting rods 54 are respectively arranged on both sides of the lock chamber 3 and pass through the support trunk. When the lower part of the lock chamber is connected, the support frame is connected with the connecting rod, thereby realizing the extension of the length of the support frame, so that the support frame can still play a supporting role after the branch trunk penetrates through the lower part of the lock chamber.

The invention provides a construction method for a small-section traffic tunnel entering a diversion lock chamber with a thin, high and special-shaped space structure. During the construction process, the position of the vault side wall of the tunnel is initially supported to strengthen the structural strength of the water diversion tunnel. The top of the sluice chamber 3 is lifted into the upper part of the sluice chamber 3 from the transition section, and the entire sluice chamber 3 is divided into upper, middle and lower areas for excavation respectively. The layered and block method is used for excavation, and the middle of the lock chamber 3 is divided into several layers in the height direction, and the middle of the lock chamber is divided into several blocks at each layer, so that the excavation has less influence on the stability of the surrounding tunnel structure, and also It is convenient to observe the geological conditions of each layer and each block, to prevent emergencies, and to improve the safety in the construction process. The lower part of 3 is penetrated to avoid the collapse of the lock chamber 3 due to insufficient strength of the lower part of the lock chamber 3 .

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (10)

1. a small-section traffic hole into a thin, high and special-shaped space structure diversion lock chamber construction method, is characterized in that, comprises: Step 1, construction transition section: the trunk (1) lifts the roof to construct the transition section (4), and performs initial support for the vault and side walls of the transition section (4); Step 2. Construction of the sluice chamber: the transition section (4) lifts the roof to construct the sluice chamber (3), and the dome and side walls of the sluice chamber (3) are initially supported. The upper part of the sluice chamber (3) is constructed by the step method. (3) The middle part is constructed by layered and block method; Step 3, excavate the branch trunk: excavate the branch trunk (2) horizontally, so that the branch trunk (2) penetrates the lower part of the lock chamber (3). 2. The method for constructing a small-section traffic tunnel into a diversion lock chamber with a thin, high, and special-shaped space structure according to claim 1, wherein the step 1 further comprises a step 1.1, optimizing the shape of the transition section: the transition section (4) A plurality of lock chamber interfaces (41) are arranged thereon, and the axes of the lock chamber interfaces (41) are arranged perpendicular to the side walls of the lock chamber (3). 3. The construction method for the diversion lock chamber of a small-section traffic hole entering a thin, high and special-shaped space structure according to claim 1, wherein the initial support comprises spraying concrete on the dome and the side wall, and installing several supports rack (5). 4. The method for constructing a small-section traffic hole into a diversion lock chamber with a thin, high and special-shaped space structure according to claim 3, wherein the support frame (5) comprises an arc-shaped rod (51) adapted to the shape of the vault , the two ends of the arc rod (51) are respectively provided with uprights (52). 5. The method for constructing a small-section traffic tunnel into a diversion lock chamber with a thin, tall, and special-shaped space structure according to claim 1, wherein the layered and block method comprises: first, placing the middle part of the lock chamber (3) along the lock chamber (3). 3) The height direction is divided into several mining layers (31), and then each mining layer (31) is divided into several mining blocks (311), one mining block (311) is selected for mining, and other mining blocks (311) are selected for mining. ) are excavated in sequence, and the height of each excavation is the same as the height of the excavation layer (31). 6. The method for constructing a small-section traffic hole into a diversion lock chamber with a thin, tall, and special-shaped space structure according to claim 5, characterized in that, for several excavated blocks (311) on each floor, the first excavated excavated block (311) adopts vertical shallow hole blasting, and other excavation blocks (311) adopt pre-split blasting. 7. The method for constructing a small-section traffic hole into a diversion lock chamber with a thin, tall, and special-shaped space structure according to any one of claims 1-6, characterized in that, in the step 2, after the construction in the middle of the lock chamber (3) is completed , a grouting hole is opened on the side wall of the middle part of the lock chamber (3), and a grouting anchor pipe is arranged in the grouting hole. 8. The construction method for a small-section traffic hole entering a diversion lock chamber with a thin, tall and special-shaped space structure according to any one of claims 1-6, wherein in the step 3, the branch trunk (2) enters the lock chamber ( 3) In the construction of the lower part, the bottom plate, side wall, and vault of the support trunk (2) are all constructed by blasting with enlarged external angle. 9. The construction method for a small-section traffic hole entering a diversion lock chamber with a thin, tall and special-shaped space structure according to any one of claims 1-6, wherein in the step 3, in the process of excavation, from the branch trunk ( 2) When entering the lower part of the lock chamber (3), manual trimming is used for the sudden change of clearance between the branch trunk (2) and the lock chamber (3). 10. The construction method for a small-section traffic hole entering a diversion lock chamber with a thin, high and special-shaped space structure according to any one of claims 1-6, wherein in the step 3, a connecting rod is arranged at the bottom of the branch trunk (2). (54), the connecting rod (54) is detachably connected with the support frame (5) in the lock chamber (3).

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