CN110644294A - A ballastless track high-speed railway anti-bulge and anti-slip structure and construction method - Google Patents

Abstract

The invention discloses an anti-bulge and anti-slip structure and a construction method for a ballastless track high-speed railway. The anti-bump and anti-slip structure comprises a bottom arch arranged on the base surface of a road cutting excavation. The bottom arch is a plate structure and is bent downward. A plurality of anchoring piles are arranged at intervals on both sides of the bottom arch, and all the anchoring piles are rigidly connected to the sides of the bottom arch. There are also multiple wing spars on both sides of the bottom arch, and each of the wing spars is located on the same side. Between the adjacent anchoring piles, one side of the spar is in contact with the cutting slope, and the other side forms a rigid connection with the side of the bottom arch. In the invention, the bottom arch is arranged to bear the expansion force of the base, and finally the expansion force is converted into the thrust in the tangential direction on both sides of the bottom arch, which is transmitted to the anchoring piles on both sides to balance a part of the thrust of the side slopes on both sides; The wing spars are arranged on both sides of the arch, which increases the contact area between the bottom arch and the rock, so that the two sides can provide greater binding force, and can diffuse the pressure on the arch side and reduce the compressive stress on the rock.

Description

A ballastless track high-speed railway anti-bulge and anti-slip structure and construction method

technical field

The invention relates to the field of roadbed engineering, in particular to an anti-bulge and anti-slip structure and a construction method suitable for a ballastless track high-speed railway in an expansive rock area.

Background technique

High-speed railways, especially ballastless railways, have strict control over the deformation of subgrade arches and slope stability. However, with the rapid development of high-speed railways, it is inevitable to encounter deep excavation of cuttings in expansive rock areas during the construction process. Under the condition of infiltration, the wet weight of the rock mass increases, the shear strength decreases and the expansion effect occurs, which causes the instability of the slope and the uplift of the base, which seriously affects the operation safety of the train.

At present, flexible measures such as anchor cables and pile-sheet structure reinforcement measures are often used to resist base uplift. Practice has proved that flexible measures such as anchor cables and other flexible measures are not effective in resisting uplift, while simple pile-sheet structure reinforcement measures have shortcomings such as excessive pile section size; expansion The support structure of anti-sliding piles is often used in the reinforcement of rock slopes. However, due to the expansion of the slope rock mass and the action of earth pressure, the size of the cross-section of the pile body is often large, and the number of masonry workers is large, which is uneconomical. Therefore, for the ballastless track high-speed railway project in the expansive rock area, an anti-bulge and anti-slip structure is urgently needed to solve the existing problems, and it should have the characteristics of convenient construction, economical rationality, safety and environmental protection.

SUMMARY OF THE INVENTION

The purpose of the invention is to provide a ballastless track high-speed railway anti-bulge and anti-slip structure and construction method in order to solve the problems of ballastless track subgrade base deformation and slope stability in deep cutting and expansive rock sections, which can effectively prevent and control The upper arch deformation of the expansive rock subgrade base ensures the stability of the expansive rock slope and meets the requirements of high-speed railways for line smoothness and slope stability.

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

A ballastless track high-speed railway anti-bulge and anti-slip structure, comprising a bottom arch arranged on the base surface of a cutting excavation, the bottom arch is a plate structure and bent downward, and a plurality of anchors are arranged at intervals on both sides of the bottom arch All the anchoring piles form a rigid connection with the side of the bottom arch. There are also a plurality of wing spars on both sides of the bottom arch, each of which is located between the adjacent anchoring piles on the same side, and one side of the wing spars is connected to the side of the bottom arch. The cutting slope is in contact, and the other side forms a rigid connection with the side of the bottom arch.

By setting the bottom arch on the base, the invention restrains the expansion and deformation of the base, bears the expansion force of the base, and finally converts the expansion force into the thrust in the tangential direction on both sides of the base arch, and transmits it to the anchoring piles on both sides to balance the two sides. Part of the thrust of the side slope; the anchoring piles on the left and right sides of the cutting are connected with the bottom arch to form a combined structure, which can make full use of the thrust on both sides of the cutting to balance the thrust on the opposite side and reduce the structure size. At the same time, wings are set on both sides of the bottom arch between the piles The beam increases the contact area between the bottom arch and the rock, so that the two sides can provide greater binding force, and can diffuse the pressure on the arch side and reduce the compressive stress on the rock; this structure not only prevents the expansion of the rock base The upper arch deformation is beneficial to the stability of the expansive rock slope, and the excavation of the slope on both sides is reduced. The structure is novel, the construction is simple, and it has a broad application prospect.

As a preferred solution of the present invention, the anchoring pile is a bottom-expanded anchoring pile, the cross section of the upper pile body is a rectangular section, and the end of the bottom-expanded pile is a trapezoidal platform structure and penetrates deep into the stable bedrock. By adopting the expanded bottom anchoring pile, the end of the expanded bottom pile greatly increases the pull-out resistance of the foundation structure of the anchoring pile and balances the expansion force borne by the bottom arch.

As a preferred solution of the present invention, the wing spar has a trapezoidal body structure, the small end is connected to the side surface of the bottom arch, and the large end is in contact with the cutting side slope. By adopting the trapezoidal body structure spar, the contact area with the slope is increased.

As a preferred solution of the present invention, a water-proof and anti-seepage layer is laid on the top surface of the bottom dome. The waterproof and seepage barrier layer has good sealing performance, which blocks the surface seepage water on the top surface of the bottom vault, and facilitates the discharge of the surface seepage water.

As a preferred solution of the present invention, a drainage dead pipe is arranged above the water-proof and anti-seepage layer, and the drainage dead pipe is longitudinally arranged at the lowest part of the mid-span of the top surface of the bottom vault. The drain blind pipe is beneficial to discharge the ground seepage water blocked on the top surface of the bottom vault.

As a preferred solution of the present invention, a reverse filter layer is provided outside the drainage dead pipe. A filter layer is arranged outside the drainage blind pipe, which can prevent the loss of fine-grained soil at the bottom of the subgrade and block the drainage blind pipe.

As a preferred solution of the present invention, the bottom arch, the anchoring pile and the spar are an integral structure of reinforced concrete.

As a preferred solution of the present invention, the waterproof and anti-seepage layer is a composite waterproof and drainage board.

As a preferred solution of the present invention, the filter layer is geotextile and sand and gravel.

A construction method of a ballastless track high-speed railway anti-bulge and anti-slip structure, comprising the following steps:

Step 1. Excavate the expansive rock cutting slope in stages and protect it, and do temporary drainage until the design elevation of the top surface of the anchoring pile is reached;

Step 2: Determine the position of each anchoring pile, excavate the pile well, and set up the protective wall in time;

Step 3: Bind the reinforcement cage of the anchoring pile, and reserve the connecting reinforcement at the connection with the bottom arch, and then cast the pile body continuously at one time;

Step 4: After the anchoring pile concrete reaches the design strength, excavate the bottom arch groove and the spar grooves on both sides, and clean the slag in the groove;

Step 5: Set up the construction formwork, place the bottom arch and the spar reinforcement cage, and extend the connecting reinforcement bars reserved for the pile body into the reinforcement cage of the bottom arch, and the longitudinal axis reinforcement bars on both sides of the bottom arch go deep into the spar reinforcement cage, pouring concrete;

Step 6: After the bottom arch concrete reaches the design strength, lay a water-proof and anti-seepage layer on the top surface of the bottom arch;

Step 7. Set up a drainage dead pipe along the longitudinal direction of the bottom arch at the lowest part of the bottom arch, and set up a reverse filter layer outside the drainage dead pipe;

Step 8: Fill the bottom layer of the foundation bed and the surface layer of the foundation bed in layers.

In the present invention, through steps 1 to 8, the bottom arch, anchoring piles and spar of the reinforced concrete integral structure are arranged on the base, which can effectively prevent the upper arch deformation of the expansive rock base, prevent the slope from slipping, and is beneficial to the expansive rock edge At the same time, it reduces the excavation of the side slopes on both sides, meets the requirements of high-speed railways for line smoothness and slope stability, and has the characteristics of convenient construction, economical rationality, safety and environmental protection.

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

1. The present invention constrains the expansion and deformation of the base by setting the bottom arch on the base, bears the expansion force of the base, and finally converts the expansion force into the thrust in the tangential direction on both sides of the base arch, and transmits it to the anchoring piles on both sides. Part of the thrust of the side slopes on both sides; the anchoring piles on the left and right sides of the cutting are connected with the bottom arch to form a combined structure, which can make full use of the thrust on both sides of the cutting to balance the thrust on the opposite side and reduce the structure size. The setting of the wing spar increases the contact area between the bottom arch and the rock, so that the two sides can provide greater binding force, and can spread the pressure on the arch side and reduce the compressive stress on the rock; this structure not only prevents expansion The upper arch deformation of the rock base is also beneficial to the stability of the expansive rock slope, reducing the excavation of the slopes on both sides, the structure is novel, the construction is simple, and has broad application prospects;

2. By using the bottom-expanded anchor pile, the bottom-expanded pile end greatly increases the pull-out resistance of the anchor pile foundation structure and balances the expansion force borne by the bottom arch; the trapezoidal body structure spar increases the contact area with the slope;

3. By laying a waterproof and seepage-proof layer on the top surface of the bottom arch, the waterproof and seepage-proof layer has good sealing performance, and the surface seepage water is blocked on the top surface of the bottom arch, which is convenient for the discharge of surface seepage water;

4. Drainage blind pipes are arranged above the water-proof and anti-seepage layer, and the drainage blind pipes are arranged longitudinally along the line at the lowest part of the mid-span of the top surface of the bottom vault, which is beneficial to discharge the surface seepage water blocked on the top surface of the bottom vault;

5. By setting a reverse filter layer outside the drainage blind pipe, the reverse filter layer can prevent the loss of fine-grained soil at the bottom of the subgrade and block the drainage blind pipe.

Description of drawings

1 is a schematic cross-sectional view of the anti-bulge and anti-slip structure of the ballastless track high-speed railway in the present invention.

FIG. 2 is a partial enlarged view of part A in FIG. 1 .

FIG. 3 is a longitudinal cross-sectional schematic diagram of the anti-bulge and anti-slip structure of the ballastless track high-speed railway in the present invention.

Figure 4 is a schematic diagram of the structure of the wing spar.

Figure 5 is a schematic diagram of the structure of the trapezoidal platform at the lower part of the anchoring pile.

Marked in the figure: bottom arch 1, anchoring pile 2, drainage blind pipe 3, waterproof and impermeable layer 4, anti-filter layer 5, connecting steel bar 6, welding point 7, wing spar 8, expanded bottom trapezoidal platform 9.

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

This embodiment provides an anti-bulge and anti-slip structure for a ballastless track high-speed railway;

As shown in Figures 1 to 5, the anti-bulge and anti-slip structure of the ballastless track high-speed railway in this embodiment includes a bottom arch 1 arranged on the base surface of the cutting excavation, and the bottom arch 1 is a plate structure and faces downward. Bending, a plurality of anchoring piles 2 are arranged at intervals on both sides of the bottom arch 1, and all the anchoring piles 2 form a rigid connection with the sides of the bottom arch 1. The wing spar 8 is located between the adjacent anchoring piles 2 on the same side, and one side of the wing spar 8 is in contact with the cutting slope, and the other side forms a rigid connection with the side surface of the bottom arch 1 .

By setting the bottom arch on the base, the invention restrains the expansion and deformation of the base, bears the expansion force of the base, and finally converts the expansion force into the thrust in the tangential direction on both sides of the base arch, and transmits it to the anchoring piles on both sides to balance the two sides. Part of the thrust of the side slope; the anchoring piles on the left and right sides of the cutting are connected with the bottom arch to form a combined structure, which can make full use of the thrust on both sides of the cutting to balance the thrust on the opposite side and reduce the structure size. At the same time, wings are set on both sides of the bottom arch between the piles The beam increases the contact area between the bottom arch and the rock, so that the two sides can provide greater binding force, and can diffuse the pressure on the arch side and reduce the compressive stress on the rock; this structure not only prevents the expansion of the rock base The upper arch deformation is beneficial to the stability of the expansive rock slope, and the excavation of the slope on both sides is reduced. The structure is novel, the construction is simple, and it has a broad application prospect.

In this embodiment, the anchoring pile 2 is a bottom-expanding anchoring pile, the cross section of the upper pile body is a rectangular section, and the end of the bottom-expanding pile is a trapezoidal platform 9 with expanded bottom, which penetrates deep into the stable bedrock. By adopting the expanded bottom anchoring pile, the end of the expanded bottom pile greatly increases the pull-out resistance of the foundation structure of the anchoring pile and balances the expansion force borne by the bottom arch.

In this embodiment, the spar 8 is a trapezoid structure, the small end is connected with the side surface of the bottom arch 1, and the large end is in contact with the cutting side slope. By adopting the trapezoidal body structure spar, the contact area with the slope is increased.

In this embodiment, a water-proof and anti-seepage layer 4 is laid on the top surface of the bottom arch 1 . The waterproof and seepage barrier layer has good sealing performance, which blocks the surface seepage water on the top surface of the bottom vault, and facilitates the discharge of the surface seepage water.

In this embodiment, a drainage blind pipe 3 is arranged above the water-proof and anti-seepage layer 4 . Multiple water seepage holes block the surface seepage water on the top surface of the bottom arch and enter the drainage blind pipe through the seepage holes for drainage.

In this embodiment, an anti-filter layer 5 is provided outside the drain blind pipe 3 . A filter layer is arranged outside the drainage blind pipe, which can prevent the loss of fine-grained soil at the bottom of the subgrade and block the drainage blind pipe.

In this embodiment, the bottom arch 1 , the anchoring piles 2 and the wing spar 8 are integral structures of reinforced concrete.

In this embodiment, the waterproof and anti-seepage layer 4 is a composite waterproof and drainage board. The composite waterproof and drainage board is a composite structure with drainage and isolation functions composed of a three-dimensional geonet core and acupuncture perforated geotextiles adhered on both sides.

In this embodiment, the filter layer 5 is geotextile and sand and gravel. Geotextile, also known as geotextile, is a permeable geosynthetic material made of synthetic fibers by needle punching or weaving. After the surface seepage water passes through the anti-filtration layer formed by geotextile and sand and gravel, it enters the drainage blind pipe through the seepage hole.

Example 2

The present embodiment provides a construction method for the anti-bulge and anti-slip structure of the ballastless track high-speed railway in Embodiment 1, comprising the following steps:

Step 1. Excavate the expansive rock cutting slope in stages and protect it, and do temporary drainage until the design elevation of the top surface of the anchoring pile is reached;

Step 2: Accurately determine the position of each anchoring pile, excavate the pile well, and set up the protective wall in time;

Step 3: Binding the reinforcement cage of the anchoring pile 2, and reserving a certain length of connecting reinforcement 6 at the connection with the bottom arch 1, which is connected with the main reinforcement of the reinforcement cage of the anchoring pile 2, and then continuously cast-in-place concrete at one time;

Step 4. After the concrete of the anchoring pile 2 reaches the design strength and the test is qualified, excavate the bottom arch 1 slot and the wing spar 8 slots on both sides, and clean the slag body in the slot;

Step 5, erect the construction formwork, place the reinforcement cages of the bottom arch 1 and the wing spar 8, and extend the connecting reinforcement bars 6 reserved by the pile body into the reinforcement cage of the bottom arch 1, and the longitudinal axis reinforcement bars on both sides of the bottom arch 1 are deep into the wings. In the reinforcement cage of beam 8, the main reinforcement of the bottom arch 1 and the anchoring pile 2 and the connecting reinforcement 6 are connected by welding (such as welding point 7), and then the bottom arch and the spar concrete are poured;

Step 6: After the bottom arch concrete reaches the design strength, a layer of composite waterproof and drainage board is laid on the top surface of the bottom arch 1 as the water-proof and seepage-proof layer 4;

Step 7: A drainage dead pipe 3 is arranged longitudinally along the line at the lowest part of the bottom arch 1, and a geotextile and sand gravel are arranged outside the drainage dead pipe 3 as a filter layer 5;

Step 8: Fill the bottom layer of the foundation bed and the surface layer of the foundation bed in layers.

In the present invention, through steps 1 to 8, the bottom arch, anchoring piles and spar of the reinforced concrete integral structure are arranged on the base, which can effectively prevent the upper arch deformation of the expansive rock base, prevent the slope from slipping, and is beneficial to the expansive rock edge At the same time, it reduces the excavation of the side slopes on both sides, meets the requirements of high-speed railways for line smoothness and slope stability, and has the characteristics of convenient construction, economical rationality, safety and environmental protection.

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 principles of the present invention shall be included in the protection scope of the present invention. Inside.

Claims (10)

1. an anti-bulge and anti-slip structure of a ballastless track high-speed railway, is characterized in that, comprises the bottom arch that is arranged on the base surface of cutting excavation, and the bottom arch is a plate structure and is bent downward, and both sides of the bottom arch are A plurality of anchoring piles are arranged at intervals, and all the anchoring piles form a rigid connection with the side surface of the bottom arch. There are also a plurality of wing spars on both sides of the bottom arch, and each of the wing spars is located between the adjacent anchoring piles on the same side, And one side of the spar is in contact with the cutting slope, and the other side forms a rigid connection with the side of the bottom arch. 2. The anti-bulge and anti-slip structure of ballastless track high-speed railway according to claim 1, is characterized in that, described anchoring piles are bottom-expanded anchoring piles, the cross-section of the upper pile body is a rectangular section, and the bottom-expanded pile ends are Trapezoidal platform structure, and deep into the stable bedrock. 3. The anti-bulge and resistance-slip structure of the ballastless track high-speed railway according to claim 2, wherein the wing spar is a trapezoidal body structure, the small end is connected with the side of the bottom arch, and the large end is in contact with the cutting side slope. 4. The anti-bulge and anti-slip structure of a ballastless track high-speed railway according to claim 3, characterized in that, a water-proof and anti-seepage layer is laid on the top surface of the bottom vault. 5 . The anti-bulge and anti-slip structure of a ballastless track high-speed railway according to claim 4 , wherein a drainage blind pipe is arranged above the water-proof and anti-seepage layer, and the drainage blind pipe is arranged at the bottom along the longitudinal direction of the line. 6 . The lowest point of the mid-span of the vault surface. 6 . The anti-bulge and anti-slip structure of the ballastless track high-speed railway according to claim 5 , wherein a reverse filter layer is provided outside the blind drainage pipe. 7 . 7 . The anti-bulge and anti-slip structure of a ballastless track high-speed railway according to claim 6 , wherein the bottom arch, the anchoring pile and the wing spar are an integral structure of reinforced concrete. 8 . 8 . The anti-bulge and anti-slip structure of a ballastless track high-speed railway according to claim 4 , wherein the waterproof and anti-seepage layer is a composite waterproof and drainage board. 9 . 9 . The anti-bulge and anti-slip structure of a ballastless track high-speed railway according to claim 6 , wherein the anti-filter layer is a geotextile and sand and gravel. 10 . 10. The construction method of the anti-bulge and anti-slip structure of ballastless track high-speed railway as claimed in claim 7, is characterized in that, comprises the following steps: Step 1. Excavate the expansive rock cutting slope in stages and protect it, and do temporary drainage until the design elevation of the top surface of the anchoring pile is reached; Step 2: Determine the position of each anchoring pile, excavate the pile well, and set up the protective wall in time; Step 3: Bind the reinforcement cage of the anchoring pile, and reserve the connecting reinforcement at the connection with the bottom arch, and then cast the pile body continuously at one time; Step 4: After the anchoring pile concrete reaches the design strength, excavate the bottom arch groove and the spar grooves on both sides, and clean the slag in the groove; Step 5: Set up the construction formwork, place the bottom arch and the spar reinforcement cage, and extend the connecting reinforcement bars reserved for the pile body into the reinforcement cage of the bottom arch, and the longitudinal axis reinforcement bars on both sides of the bottom arch go deep into the spar reinforcement cage, pouring concrete; Step 6: After the bottom arch concrete reaches the design strength, lay a water-proof and anti-seepage layer on the top surface of the bottom arch; Step 7. Set up a drainage dead pipe along the longitudinal direction of the line at the lowest part of the bottom arch, and set a reverse filter layer outside the drainage dead pipe; Step 8: Fill the bottom layer of the foundation bed and the surface layer of the foundation bed in layers.

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