CN106968712A - Water rich strata tunnel bottom discharge structure and its construction method - Google Patents

Abstract

The invention relates to a tunnel bottom drainage structure in a water-rich stratum and a construction method thereof. A ballast bed bottom plate is arranged above an inverted arch, bearing piles are arranged between the ballast bed bottom plate and the inverted arch, and a water passage at the bottom of the tunnel is formed between the ballast bed bottom plate and the inverted arch. The drainage side channel is connected to the water culvert through the side ditch drainage pipe; the bottom of the water culvert is equipped with a water collection well, and the lower end of the water collection well passes through the inverted arch and extends to the filter water collection device under the inverted arch. The bottom and side walls of the water collection well are both A drain hole is provided, a filter layer is arranged outside the drain hole, and a one-way drainage device is arranged in the sump well. In the present invention, the filling part of the inverted arch in the prior art is replaced by the bottom plate of the ballast bed and bearing piles, and on the basis of ensuring the safety of the tunnel structure, the cross-section area of the tunnel drainage system is increased, and the drainage capacity of the tunnel is improved; It can discharge the groundwater under the inverted arch of the tunnel in the water-rich stratum, reduce the water pressure at the bottom of the tunnel, and help prevent the occurrence of diseases such as the uplift of the tunnel inverted arch and the mud and mud of the ballast bed.

Description

Drainage Structure and Construction Method of Tunnel Bottom in Water-rich Stratum

technical field

The invention relates to the technical field of tunnel drainage facilities, in particular to a tunnel bottom drainage structure in a water-rich stratum and a construction method thereof.

Background technique

In recent years, with the large-scale construction of transportation infrastructure, many long and complex water-rich tunnels are being built or have been built. The existing tunnel drainage design is based on the conventional tunnel drainage design. The water around the tunnel structure permeates through the initial support and is drained to the central drainage ditch in the tunnel structure through the drainage blind pipe, and finally discharged out of the tunnel. Specifically, as shown in Figure 1, the groundwater penetrates into the circular drainage blind pipe (serial number 2) through the initial support (serial number 1). Its lower end is connected with the vertical drainage blind pipe (serial number 8), and the vertical drainage blind pipe (serial number 8) has a water outlet every 10-20m, and is connected with the drainage side ditch (serial number 6) through the horizontal drainage blind pipe (serial number 5). The drainage side ditch (No. 6) is mainly used to collect groundwater and introduce the groundwater into the central drainage ditch (No. 7) through the horizontal drainage channel (No. 9), and finally drain the groundwater out of the tunnel.

However, for water-rich tunnels, especially under the conditions of continuous rainfall or extreme rainstorms, due to the limited degree of freedom of the cross-section of the channel inside the tunnel and the limited drainage capacity, it is impossible to timely and effectively drain the accumulated water behind the tunnel lining, making the arch ring Under the action of high water pressure, the tunnel lining will be cracked, water seepage and other problems will be caused, which will cause traffic safety hazards in the tunnel.

In addition, the existing tunnel drainage design uses the gravity of water to drain the accumulated water behind the tunnel arch ring from top to bottom to the central drainage ditch. Since the central drainage ditch is set inside the tunnel, the water at the bottom of the tunnel cannot be discharged; in addition, the bottom of the tunnel (referred to as the tunnel bottom) in the existing drainage system mainly includes: the surrounding rock at the bottom, the initial support of the inverted arch, and the secondary concrete lining of the inverted arch. , Invert arch filling, pavement structure, road side ditch, deep buried ditch, curb stone, cable trough, etc. Due to the lack of an effective drainage system at the bottom of the tunnel, the internal drainage cannot discharge the water at the bottom of the tunnel, resulting in the inability to effectively drain the accumulated water below the inverted arch of the tunnel, causing the inverted arch to bear part of the water pressure, resulting in uplift of the inverted arch, deformation of the ballast bed, and cracks in the lining It is extremely difficult to repair and treat water damage events such as damage to the track bed and mud and mud.

Contents of the invention

The present invention aims to provide a tunnel bottom drainage structure in water-rich strata and its construction method. The ballast floor and bearing piles are arranged at intervals to replace the inverted arch filling in the prior art. The cross-sectional area is much larger than the central drainage ditch, and it has a strong drainage capacity, which can meet the large drainage needs of water-rich tunnels. It can quickly, timely and effectively drain the high-pressure water behind the tunnel lining, and reduce the damage of groundwater to the tunnel lining structure.

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

The drainage structure of the tunnel bottom in water-rich stratum includes the inverted arch and drainage side ditches on both sides of the tunnel. The ballast bed bottom plate is set above the inverted arch, and bearing piles are arranged between the ballast bed bottom plate and the inverted arch. A water culvert at the bottom of the tunnel is formed between the arches, and the drainage side channel is connected to the water culvert through a side ditch drain pipe, and a plurality of side ditch drain pipes are arranged at intervals.

In order to facilitate the discharge of accumulated water below the inverted arch, a water collecting well is arranged on the bottom of the culvert, the lower end of the water collecting well extends through the inverted arch to below the inverted arch, and the bottom and side walls of the water collecting well are provided with drain holes , the drain hole is located below the inverted arch, a filter layer is provided outside the drain hole, and a one-way drainage device is provided in the water collection well.

Further, the water collection well phase passes through the water collection device, the water collection device is located under the inverted arch, the water collection device includes a water collection pipe, the side wall of the water collection pipe is provided with water inlets at intervals, the The lower end of the water collection well extends into the water collection pipe, the drain hole communicates with the interior of the water collection pipe, and the first filter layer is filled between the inner wall of the water collection pipe and the outer wall of the water collection well.

Preferably, there is a second filter layer between the drain hole and the first filter layer, the second filter layer is a fine sand filter layer, and the first filter layer is a coarse sand filter layer. Further, a stainless steel filter mesh layer is provided between the drain hole and the second filter layer.

Further preferably, the filtering water collecting device further includes a foundation pit, the water collecting pipe is arranged in the foundation pit, and the scope of the foundation pit outside the water collecting pipe and the water collecting well is filled with a pebble filter layer.

Wherein, the one-way drainage device includes a movable cover device and a tension spring, and the movable cover device includes a cover, a cover supporting member and a loose-leaf rotating shaft, and one side of the cover is connected to the water collection well through the loose-leaf rotating shaft. The other side of the cover plate is pressed on the cover plate supporting member, the cover plate supporting member is fixedly connected with the water collection well, one end of the tension spring is connected to the bottom of the cover plate, and the other end of the tension spring One end is connected with the bottom of the water collection well, and the movable cover device is located above the drain hole.

Preferably, the water collection wells on the left and right sides of the culvert are arranged symmetrically, and the tension springs in the water collection wells adjacent to the tunnel centerline have a higher stiffness coefficient than those in other water collection wells.

In order to facilitate the inspection, maintenance and dredging of the water culvert at the bottom of the tunnel, inspection wells are arranged at intervals along the longitudinal direction of the tunnel in the center of the ballast bed floor, and the inspection wells lead to the water culvert.

Among them, an arch wall is also included. The arch wall includes primary support, waterproof layer and secondary lining arranged from the outside to the inside. A circular drainage blind pipe is arranged between the primary support and the waterproof layer. The two ends of the circular drainage blind pipe are respectively connected to the vertical drainage blind pipe. The pipe wall of the longitudinal drainage blind pipe is provided with a plurality of water outlets at intervals. The water outlets are connected to the drainage side ditch through the horizontal drainage blind pipe. The drainage blind pipe is higher than the water culvert.

The construction method of water-rich strata tunnel bottom drainage structure is characterized in that: comprises the following steps:

Step 1, carry out reinforcement binding to inverted arch, bearing pile and ballast bed floor;

Step 2. Perform vertical casting of the inverted arch, and after the concrete is solidified and formed, perform vertical casting of the bearing piles; after the bearing piles are solidified and formed, perform vertical casting of the bottom plate of the ballast bed.

Further, before the step 1, first dig out a quadrangular prism-shaped foundation pit at the lower part of the inverted arch of the tunnel, place a water collection pipe seat at the bottom of the foundation pit, and install the water collection pipe on the water collection pipe seat;

In the step 1, firstly, the inverted arch, the water collection well, the bearing pile, the bottom plate of the ballast bed and the inspection well are reinforced;

Described step 2 comprises the following steps:

2.1 Perform vertical formwork pouring on the inverted arch and the water collection well. After the concrete is solidified and formed, the pre-buried weep hole steel pipe will form the weep hole;

2.2 Install a filter device at the end of the drain hole at the outer end of the drain hole, and set a stainless steel filter layer and a fine sand filter layer inside the filter device at the end of the drain hole in sequence;

2.3 Apply a coarse sand filter layer between the inner wall of the water collection pipe and the outer wall of the water collection well;

2.4 Apply a pebble filter layer within the scope of the foundation pit other than the water collection pipe and the water collection well;

2.5 Install a one-way drainage device inside the water collection well, and fix the loose-leaf shaft and the cover plate supporting member on the inner wall of the water collection well. The loose-leaf shaft and the cover plate supporting member are located on the opposite side of the water collection well, and the position of the loose-leaf shaft is high. At the position of the support member of the cover plate and the drain hole, one side of the cover plate is fixed to the loose-leaf shaft, one end of the tension spring is connected to the bottom of the cover plate, and the other end of the tension spring is connected to the bottom of the water collection well;

2.6 Perform vertical formwork pouring on the bearing piles, and perform vertical formwork pouring on the bottom plate of the ballast bed after the bearing piles are solidified and formed.

Compared with the prior art, the present invention has the following beneficial effects:

In the present invention, the filling part of the inverted arch in the prior art is replaced by the bottom plate of the ballast bed and bearing piles, and on the basis of ensuring the safety of the tunnel structure, the cross-section area of the tunnel drainage system is increased, and the drainage capacity of the tunnel is improved; The lower part of the arch is equipped with a water collection well and a filter water collection device, which realizes the discharge of the underground under the tunnel invert in the water-rich stratum, reduces the water pressure at the bottom of the tunnel, and is beneficial to prevent the occurrence of diseases such as the uplift of the tunnel invert and the mud and mud of the ballast bed. . An inspection well is set in the center of the ballast bed floor along the longitudinal direction of the tunnel, so that relevant workers can pass through the water culvert for inspection, maintenance and dredging.

Description of drawings

Fig. 1 is the structural representation of the tunnel drainage system cross-section in the prior art;

Fig. 2 is the structural representation of cross section of the present invention;

Fig. 3 is the structural representation of longitudinal section of the present invention;

Fig. 4 is the front view of filter water collecting device;

Fig. 5 is a side view of the filter water collecting device;

Fig. 6 is a schematic diagram of the drainage path in the front view direction of the filter water collecting device;

Fig. 7 is a schematic diagram of the drainage path in the side view direction of the filter water collecting device;

Fig. 8 is the schematic diagram of the drainage mode of embodiment 2 during the dry season;

Fig. 9 is a schematic diagram of the drainage mode of embodiment 2 during the water-rich season;

Fig. 10 is a schematic diagram of the drainage mode of Embodiment 2 during the extreme rainstorm season;

In the figure: 1-primary support, 2-circular drainage blind pipe, 3-waterproof layer, 4-secondary lining, 5-horizontal drainage blind pipe, 6-drainage side ditch, 7-central drainage ditch, 8-longitudinal Drainage blind pipe, 9-horizontal drainage channel, 10-inspection well, 11-filtering water collection device, 12-side ditch drainage pipe, 13-track bed floor, 14-pebble filter layer, 15-water collection pipe, 16-water inlet , 17-first filter layer, 18-drainage hole, 19-collection pipe seat, 20-collection well, 21-movable cover device, 22-first tension spring, 23-second tension spring , 24-Water hole steel pipe, 25-Water hole end filter device, 26-Second filter layer, 27-Stainless steel filter screen, 28-Cover plate, 29-Cover plate supporting member, 30-Loose leaf shaft, 31 - bearing pile, 32 - water culvert.

detailed description

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings.

Example 1

As shown in Figure 2, the tunnel bottom drainage structure in water-rich strata disclosed by the present invention includes an inverted arch and drainage side ditches 6 on both sides of the tunnel. Bearing piles 31 are arranged, and a culvert 32 at the bottom of the tunnel is formed between the ballast bed floor 13 and the inverted arch. The drainage side ditch 6 is connected to the water culvert 32 through the side ditch drain pipe 12, and multiple side ditch drain pipes 12 are arranged at intervals.

In order to facilitate the inspection, maintenance and dredging of the culvert 32 at the bottom of the tunnel, inspection wells 10 are arranged at intervals along the longitudinal direction of the tunnel in the center of the ballast bed floor 13 , and the inspection wells 10 lead to the culvert 32 . In the center of the ballast bed floor, inspection wells 10 are set at intervals of 50m along the longitudinal direction of the tunnel. Relevant workers can enter the culvert 32 at the bottom of the tunnel through the inspection wells 10 to carry out relevant inspection, maintenance and dredging work.

The arch wall on the upper part of the inverted arch of the present invention is basically the same as the prior art tunnel. The arch wall includes primary support 1, waterproof layer 3 and secondary lining 4 arranged from outside to inside, and the interval between primary support 1 and waterproof layer 3 is There is a circular drainage blind pipe 2, and the two ends of the annular drainage blind pipe 2 are respectively connected to the vertical drainage blind pipe 8. The pipe wall of the longitudinal drainage blind pipe 8 is provided with a plurality of water outlets at intervals, and the water outlets pass through the horizontal drainage blind pipe. 5 is connected to the drainage side ditch 6, the vertical drainage blind pipe 8 is higher than the water culvert 32, and the drainage side ditch 6 runs through the tunnel longitudinally.

When drainage is carried out in this embodiment, the groundwater above the inverted arch at the bottom of the tunnel penetrates through the primary support 1 into the circular drainage blind pipe 2 buried in the secondary lining 4, and then passes through the vertical drainage blind pipe 8 and the horizontal drainage blind pipe respectively. 5 enters the drainage side ditch 6, and part of the groundwater is discharged longitudinally outside the tunnel through the drainage side ditch 6. When the water flow in the drainage side ditch 6 increases to a certain index, part of the groundwater enters the ballast bed floor 13 and the The water culvert 32 between the inverted arches is discharged outside the tunnel body.

The invention has a large cross-section, a large drainage volume and a strong drainage capacity, and can quickly and effectively discharge the water behind the lining of the tunnel, reducing damage to the lining structure caused by high water pressure; and it is equipped with an inspection well for easy maintenance.

Example 2

The difference between this embodiment and Embodiment 1 is: as shown in Figures 2 and 3, in order to facilitate the discharge of accumulated water below the inverted arch at the same time, a water collection well 20 is arranged on the bottom surface of the water culvert 32, and the lower end of the water collection well 20 passes through the inverted arch. Extending to the bottom of the inverted arch, the bottom and side walls of the sump well 20 are provided with drain holes 18, the drain holes 18 are located below the inverted arch, and a filter layer is provided outside the drain holes 18, and a one-way drainage device is arranged in the sump well 20 .

As shown in Figure 5, the one-way drainage device includes a movable cover device 21 and a tension spring, and the movable cover device 21 includes a cover 28, a cover supporting member 29 and a hinge shaft 30, and one side of the cover 28 passes through the hinge The rotating shaft 30 is rotationally connected with the water collection well 20, the other side of the cover plate 28 is pressed on the cover plate support member 29, the cover plate support member 29 is fixedly connected with the water collection well 20, and one end of the tension spring is connected with the bottom of the cover plate 28, The other end of the tension spring is connected to the bottom of the water collection well 20 , and the movable cover device 21 is located above the drain hole 18 .

When the water pressure at the bottom of the tunnel is small, and the accumulated water pressure is less than the sum of the self-weight of the movable cover plate 28 and the tension of the tension spring, the movable cover plate 28 bears against the cover plate under the action of the tension spring and the self-weight of the cover plate. The supporting member 29 fits tightly, and the accumulated water under the inverted arch cannot enter the water culvert 32 through the water collection well 20; When combined with the tension of the tension spring, the accumulated water at the bottom of the tunnel will push the movable cover plate 28 to rotate around the loose-leaf shaft structure 30 through the water collection well 20 under the action of the water head pressure, thereby entering the water culvert 32 to realize the drainage function. And then smoothly out of the tunnel.

The present invention can adjust the stiffness coefficient K of the tension spring installed, and then control the critical water pressure of the groundwater discharge at the lower part of the inverted arch. The installation of the present invention includes two kinds of tension springs with different stiffness coefficients. The stiffness of the first tension spring 22 is The coefficient is K1, the first type of tension spring 23 and the stiffness coefficient are K2, where K1<K2, specifically, the stiffness coefficient of the tension spring in the water collection well 20 adjacent to the center line of the tunnel is K1, and the stiffness coefficient of the other water collection wells 20 The stiffness coefficient of the tension spring is K2, K1<K2. Preferably, the water collection wells 20 on the left and right sides of the water culvert 32 are arranged symmetrically with respect to the center line of the tunnel.

When drainage is carried out in this embodiment, the groundwater above the inverted arch at the bottom of the tunnel penetrates through the primary support 1 into the circular drainage blind pipe 2 buried in the secondary lining 4, and then passes through the vertical drainage blind pipe 8 and the horizontal drainage blind pipe respectively. 5 enters the drainage side ditch 6, and part of the groundwater is discharged longitudinally outside the tunnel through the drainage side ditch 6. When the water flow in the drainage side ditch 6 increases to a certain index, part of the groundwater enters the ballast bed floor 13 and the The water culvert 32 between the inverted arches is discharged outside the tunnel body. When the underground water pressure under the inverted arch of the tunnel in the water-rich stratum increases to a certain extent, the groundwater enters the water culvert 32 through the water collection well 20 under the inverted arch, and finally discharges out of the tunnel.

The invention can reduce the occurrence of water hazards such as inverted arch uplift, ballast bed deformation, mud turning, etc.; the cover plate can be automatically opened or closed according to the water pressure to control the size of the water cross section, thereby preventing side ditch water from flowing backward into the bottom of the tunnel.

Example 3

The difference between this embodiment and Embodiment 2 is that: as shown in Figures 2, 3, 4, and 5, the water collecting well 20 passes through the filtering water collecting device 11, the filtering water collecting device 11 is located under the inverted arch, and the filtering water collecting device 11 includes a water collecting device The water pipe 15 and the side wall of the water collecting pipe 15 are provided with a water inlet 16 at intervals. Wherein, the filter layer on the outside of the drain hole 18 includes the second filter layer 26 and the first filter layer 17 arranged from the inside to the outside, as preferably, the first filter layer 17 is a coarse sand filter layer, and the second filter layer 26 is For the fine sand filter layer, preferably, a stainless steel screen layer 27 is also provided between the drain hole 18 and the second filter layer 26 . Concretely, as shown in Figure 4, a drain hole end filter device 25 is installed at the outer end of the drain hole 18, and a stainless steel filter mesh layer 27 and a fine sand filter layer are sequentially arranged inside the drain hole end filter device 25. A first filter layer 17 is filled between the inner wall of the water collection pipe 15 and the outer wall of the water collection well 20 .

Filtration water collection device 11 also comprises foundation pit, and foundation pit is preferably quadrangular prism shape, is equipped with water collection pipe socket 19 at foundation pit bottom, and water collection pipe 15 is installed on the water collection pipe socket 19, and the axis of water collection pipe 15 and The axis of the water collection well 20 is vertical, and the scope of the foundation pit outside the water collection pipe 15 and the water collection well 20 is filled with a pebble filter layer 14 .

Among them, the construction steps of the water collection well 20 and the filter water collection device 11 are as follows: ① dig out a quadrangular prism-shaped foundation pit as shown in Figures 4 and 5 at the lower part of the inverted arch of the tunnel, and place a water collection pipe seat 19 and a collection pipe at the bottom. The water pipe 15 and the water collecting pipe socket 19 are prefabricated C20 concrete water collecting pipe sockets, the water collecting pipe 15 is a C35 concrete water collecting pipe, and the two sides of the water collecting pipe 15 are symmetrically provided with water inlets 16; Binding the steel bars with the inverted arch is completed, and the steel pipe 24 for the drain hole is pre-buried with the wall of the 20 hole of the water collection well and the steel pipe 24 at the bottom of the hole, and the mold is poured together. Hole end filtering device 25, stainless steel screen layer 27 and fine sand filter layer 26 are arranged in sequence in its interior; ③ apply coarse sand filter layer in the water collection pipe 15 inner range outside the water collection well 20; ④ in the water collection pipe 15 Apply a pebble filter layer in the scope of the foundation pit outside the water collection well 20; Composed with the hinge shaft 30, the tension spring can pull the cover plate 28 to rotate around the hinge shaft 30 under the action of water pressure.

As shown in Figures 6 and 7, when the water pressure of the groundwater under the inverted arch at the bottom of the tunnel in the water-rich formation increases to a certain level, the groundwater passes through the pebble filter layer of the water collection device 11, and then passes through the inlets on both sides of the water collection pipe 15. The water outlet 16 enters the inside of the water collection pipe 15; then passes through the coarse sand filter layer 17 inside the water collection pipe 15, and then passes through the fine sand filter layer 26 and the stainless steel filter layer 26 in the water discharge hole end filter device 25 arranged on the outside of the water discharge hole 18. The mesh layer 27 flows into the water collection well 20 inside through the steel pipe 24 of the scupper hole. When the water pressure under the inverted arch at the bottom of the tunnel is greater than the sum of the self-weight of the movable cover 28 and the tension of the tension spring, the accumulated water at the bottom of the tunnel will push the movable cover 28 around the loose-leaf shaft through the water collection well 20 under the action of the water head pressure. The structure 30 rotates so as to enter into the culvert 32 at the bottom of the tunnel, realize the drainage function, and then smoothly discharge out of the tunnel body.

As shown in Figure 8, during the dry season, the water pressure at the bottom of the tunnel is small, and the water pressure of the accumulated water is less than the sum of the self-weight of the movable cover plate 28 and the tension of the tension spring, and the movable cover plate 28 is in the tension between the tension spring and the cover plate. Under the action of its own weight, it fits closely with the supporting member 29 of the cover plate, and the accumulated water under the inverted arch cannot enter the tunnel bottom culvert 32 through the water collection well 20; at this time, the groundwater above the inverted arch at the bottom of the tunnel passes through the initial support 1 penetrates into the circular drainage blind pipe 2 buried in the secondary lining 4, and then enters the drainage side ditch 6 through the vertical drainage blind pipe 8 and the horizontal drainage blind pipe 5 respectively, and part of the groundwater is discharged out of the tunnel longitudinally through the drainage side ditch 6 Outside the body, part of the groundwater enters the culvert 32 between the bottom plate of the ballast bed 13 and the inverted arch through the side ditch drain pipe 12 and is discharged out of the tunnel body.

As shown in Figure 9, in the water-rich season, the water pressure under the inverted arch at the bottom of the tunnel is relatively high, and the water pressure of the accumulated water is greater than the sum of the self-weight of the movable cover 28 and the tension of the first tension spring 22, but less than that of the movable cover 28 and the tension of the second tension spring 23, the accumulated water below the inverted arch will enter the water culvert 32 for drainage through the sump 20 where the first tension spring 22 is installed, and the groundwater above the inverted arch will also pass through Drainage side ditch 6 and water culvert 32 carry out drainage.

As shown in Figure 10, when the surrounding rock of the tunnel stratum is in the extreme rainstorm season, the water pressure under the inverted arch at the bottom of the tunnel increases sharply, and when the accumulated water pressure is greater than the sum of the self-weight of the movable cover plate 28 and the tension of the tension spring, the vertical The accumulated water under the arch enters the water culvert 32 through all the sump wells 20 for drainage, while the groundwater above the inverted arch is also discharged outside the tunnel through the drainage side ditch 6 and the water culvert 32 .

The construction method of the tunnel bottom drainage structure in the water-rich stratum disclosed by the present invention comprises the following steps:

Step 1, binding steel bars to the inverted arch, inspection shaft 10, bearing pile 31 and ballast bed floor 13;

Step 2. Perform vertical casting of the inverted arch, and after the concrete is solidified and formed, perform vertical casting of the bearing pile 31;

For embodiment 2, in step 1, carry out reinforcing bar binding to inverted arch, water collection well 20, inspection well 10, bearing pile 31 and ballast bed floor 13;

In step 2, the inverted arch and the water collection well 20 are casted vertically, and after the concrete is solidified and formed, the bearing piles 31 are cast vertically;

For Example 3, during on-site construction of the tunnel bottom structure, after excavating the required space for the entire tunnel bottom structure, the tunnel inverted arch, water collection well 20, bearing pile 31, ballast bed floor 13 and inspection well 10 are bound with steel bars and vertical formwork pouring, the pouring sequence is as follows: inverted arch and water collection well 20→bearing pile 31→ballast bed floor 13 and inspection well 10, that is, after the steel bars are bound, firstly carry out vertical formwork pouring on the inverted arch and water collection well 20, and wait for After the concrete is solidified and formed, the vertical formwork of the bearing pile 31 is carried out, and finally the vertical formwork of the ballast bed floor 13 and the inspection well 10 is performed after the bearing pile 31 is solidified and formed, that is, the bottom structure of the tunnel in the water-rich stratum of the present invention is completed. construction process. details as follows:

Before step 1, at first excavate a quadrangular prism-shaped foundation pit at the bottom of the inverted arch of the tunnel, place a water collection pipe seat 19 at the bottom of the foundation pit, and install the water collection pipe 15 on the water collection pipe seat 19;

In step 1, first, the inverted arch, the water collection well 20, the bearing pile 31, the ballast bed floor 13 and the inspection well 10 are reinforced;

Step 2 includes the following steps:

2.1 Perform vertical mold pouring on the inverted arch and the water collection well 20, and after the concrete is solidified and formed, the pre-buried scupper hole steel pipe 24 forms the scupper hole 18;

2.2 Install a drain hole end filter device 25 at the outer end of the drain hole 18, and set a stainless steel filter mesh layer 27 and a fine sand filter layer inside the drain hole end filter device 25 in sequence;

2.3 Apply a coarse sand filter layer between the inner wall of the water collection pipe 15 and the outer wall of the water collection well 20;

2.4 Apply a pebble filter layer 14 within the scope of the foundation pit outside the water collecting pipeline 15 and the water collecting well 20;

2.5 Install a one-way drainage device inside the water collection well 20, fix the loose-leaf rotating shaft 30 and the cover plate supporting member 29 on the inner wall of the water collecting well 20, the loose-leaf rotating shaft 30 and the cover plate supporting member 29 are located on the opposite side of the water collecting well 20, The position of the loose-leaf rotating shaft 30 is higher than the position of the cover plate supporting member 29 and the drain hole 18, one side of the cover plate 28 is affixed to the loose-leaf rotating shaft 30, one end of the tension spring is connected with the bottom of the cover plate 28, and the The other end of the spring is connected to the bottom of the sump 20;

2.6 Perform vertical casting of the bearing piles 31, and perform vertical casting of the ballast bed floor 13 after the bearing piles 31 are solidified and formed.

For water-rich areas, especially for continuous rainfall or extreme rainstorm weather conditions, the invention has a strong displacement reserve; due to the large cross-section of the tunnel, it can quickly and effectively discharge the water behind the tunnel lining, reducing the damage of high water pressure to the lining structure The water collection well extending below the inverted arch can eliminate the accumulated water under the inverted arch and reduce the occurrence of water hazards such as inverted arch uplift, ballast bed deformation and mud turning; at the same time, the cover plate can be automatically opened or closed according to the amount of groundwater to control the cross section of water size, so as to prevent backflow of side ditch water into the bottom of the tunnel; the construction process of the invention is simple and has strong construction feasibility; the construction cost is low, and it is convenient for large-scale promotion.

Certainly, the present invention also can have other multiple implementation modes, without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding changes All changes and modifications should belong to the scope of protection of the appended claims of the present invention.

Claims (11)

1. Drainage structure at the bottom of the tunnel in water-rich strata, including the drainage side ditches (6) on both sides of the inverted arch and the tunnel, characterized in that: the ballast bed floor (13) is set at the top of the inverted arch, and the ballast bed floor (13) and the Bearing piles (31) are arranged between the inverted arches, and a culvert (32) at the bottom of the tunnel is formed between the ballast bed floor (13) and the inverted arches, and the drainage side ditch (6) passes through the side ditch drainage pipe (12 ) is connected to the water culvert (32), and the side ditch drain pipe (12) is provided with multiple intervals. 2. The tunnel bottom drainage structure in water-rich strata according to claim 1, characterized in that: the bottom surface of the culvert (32) is provided with a water collection well (20), and the lower end of the water collection well (20) passes through the inverted arch Extending to below the inverted arch, the bottom and side walls of the sump well (20) are provided with drain holes (18), the drain holes (18) are located below the inverted arch, and the outer sides of the drain holes (18) are provided with There is a filter layer, and a one-way drainage device is arranged in the water collection well (20). 3. The tunnel bottom drainage structure in water-rich strata according to claim 2, characterized in that: the water collecting well (20) passes through the filtering water collecting device (11), and the filtering water collecting device (11) is located under the inverted arch , the filter water collection device (11) includes a water collection pipe (15), the side wall of the water collection pipe (15) is provided with a water inlet (16) at intervals, and the lower end of the water collection well (20) extends into the water collection pipe In (15), the drain hole (18) communicates with the water collection pipe (15), and the first filter layer (17) is filled between the inner wall of the water collection pipe (15) and the outer wall of the water collection well (20). . 4. The water-rich ground tunnel bottom drainage structure according to claim 3, characterized in that: there is a second filter layer (26) between the drain hole (18) and the first filter layer (17), the The second filter layer (26) is a fine sand filter layer, the first filter layer (17) is a coarse sand filter layer, and a stainless steel filter is arranged between the drain hole (18) and the second filter layer (26). Mesh layer (27). 5. The tunnel bottom drainage structure in water-rich strata according to claim 3 or 4, characterized in that: the filtering water collecting device (11) also includes a foundation pit, and the water collecting pipe (15) is arranged in the foundation pit , the foundation pit beyond the water collection pipe (15) and the water collection well (20) is filled with a pebble filter layer (14). 6. The tunnel bottom drainage structure in water-rich stratum according to claim 2, characterized in that: the one-way drainage device includes a movable cover device (21) and a tension spring, and the movable cover device (21) includes Cover plate (28), cover plate supporting member (29) and loose-leaf rotating shaft (30), one side of described cover plate (28) is rotatably connected with water collection well (20) through loose-leaf rotating shaft (30), and described cover plate (28) The other side is pressed on the cover plate support member (29), the cover plate support member (29) is fixedly connected to the water collection well (20), and one end of the tension spring is connected to the cover plate (28) The bottom is connected, the other end of the tension spring is connected with the bottom of the water collection well (20), and the movable cover device (21) is located above the drain hole (18). 7. The tunnel bottom drainage structure in water-rich strata according to claim 6, characterized in that: the water collecting wells (20) on the left and right sides of the water-passing culvert (32) are symmetrically arranged, and the collecting wells (20) adjacent to the center line of the tunnel The stiffness coefficient of the tension spring in the water well (20) is greater than the stiffness coefficient of the tension spring in other water collection wells (20). 8. The tunnel bottom drainage structure in water-rich stratum according to claim 1 or 2, characterized in that: inspection wells (10) are arranged at intervals along the longitudinal direction of the tunnel in the center of the ballast bed floor (13), and the inspection wells (10) Lead to the culvert (32). 9. The tunnel bottom drainage structure in water-rich stratum according to claim 1 or 2, characterized in that it also includes an arch wall, and the arch wall includes initial support (1), waterproof layer (3) arranged from outside to inside ) and secondary lining (4), the annular drainage blind pipe (2) is arranged at intervals between the primary support (1) and the waterproof layer (3), and the two ends of the annular drainage blind pipe (2) Respectively connect the vertical blind drain pipe (8), the pipe wall of the vertical drain blind pipe (8) is provided with a plurality of water outlets at intervals, and the water outlets are connected to the drainage side ditch (6) through the horizontal drain blind pipe (5) , the vertical drainage blind pipe (8) is higher than the water culvert (32). 10. according to the construction method of the water-rich formation tunnel bottom drainage structure described in any one of claims 1-9, it is characterized in that: comprise the following steps: Step 1, carrying out reinforcement binding to the inverted arch, bearing pile (31) and ballast bed floor (13); Step 2. Perform vertical casting of the inverted arch, and after the concrete is solidified and formed, perform vertical casting of the bearing piles (31); after the bearing piles (31) are solidified and formed, perform vertical casting of the ballast bed floor (13). 11. The construction method according to claim 10, characterized in that: before said step 1, at first dig out a quadrangular prism-shaped foundation pit at the bottom of the inverted arch of the tunnel, place a water collecting pipe seat (19) at the bottom of the foundation pit, Install the water collecting pipe (15) on the water collecting pipe socket (19); In the step 1, firstly, the inverted arch, the water collection well (20), the bearing piles (31), the ballast bed floor (13) and the inspection well (10) are reinforced; Weep hole steel pipe (24); Described step 2 comprises the following steps: 2.1 Carry out vertical mold pouring to the inverted arch and the water collection well (20), after the concrete is solidified and formed, the pre-buried scupper hole steel pipe (24) forms the scupper hole (18); 2.2 Install a drain hole end filter device (25) at the outer end of the drain hole (18), and arrange a stainless steel filter layer (27) and a fine sand filter layer in sequence inside the drain hole end filter device (25); 2.3 Apply a coarse sand filter layer between the inner wall of the water collection pipe (15) and the outer wall of the water collection well (20); 2.4 Apply a pebble filter layer (14) within the scope of the foundation pit outside the water collection pipe (15) and the water collection well (20); 2.5 Install a one-way drainage device inside the water collection well (20), fix the loose-leaf shaft (30) and the cover plate supporting member (29) on the inner wall of the water collection well (20), and the loose-leaf shaft (30) and the cover plate The supporting member (29) is positioned at the opposite side of the water collection well (20), and the position of the loose-leaf rotating shaft (30) is higher than the position of the cover plate supporting member (29) and the drain hole (18), and the cover plate (28) One side is fixedly connected with the loose-leaf rotating shaft (30), and one end of the tension spring is connected with the bottom of the cover plate (28), and the other end of the tension spring is connected with the bottom of the water collection well (20); 2.6 Perform vertical casting of the bearing piles (31), and perform vertical casting of the ballast bed floor (13) after the bearing piles (31) are solidified and formed.