CN113308954B - Construction method of anchor rod foam concrete widening roadbed - Google Patents

Abstract

The invention relates to a construction method of an anchor rod foam concrete widening roadbed, which comprises the steps of firstly constructing an n-shaped foundation, then installing an L-shaped baffle plate and an inserting plate layer by layer to form a panel, carrying out foam concrete backfill pouring layer by layer, then constructing a pavement waterproof and drainage system, finally pouring a leveling layer, constructing a new pavement layer, and completing construction of the anchor rod foam concrete widening roadbed. The invention has the beneficial effects that: the n-type foundation arranged by the invention not only greatly reduces the foundation excavation amount, but also effectively improves the bearing capacity of the foundation of the foam concrete backfilling area, and the integrity with the existing roadbed is enhanced by utilizing the hollow grouting anchor rod, so that the technical benefit advantage is obvious; the inserting plate and the L-shaped baffle plate are reasonable in structure and simple and convenient to manufacture and install, the construction efficiency of the panel is effectively improved, and the construction period is shortened; the support and the support rod arranged in the invention not only improve the integrity and rigidity of the panel, but also strengthen the connection of the new roadbed and the old roadbed and reduce the settlement difference.

Description

The Construction Method of Anchor Rod Foam Concrete Widened Subgrade

technical field

The invention relates to the technical field of road engineering construction, in particular to a construction method for widening roadbeds made of anchor rod foam concrete.

Background technique

my country's highway industry has ushered in a new pattern, which is a situation where large-scale new highways are gradually transformed into a situation where reconstruction, expansion and new construction coexist. The highway reconstruction and expansion project will become the new focus of highway construction in the next decade or so. Foamed concrete has the characteristics of reducing load or earth pressure, and its mixed slurry can be self-leveling and self-compacting when it is formed; it has good construction workability, is conducive to pumping and leveling, and has good compatibility with other building materials. Can be adjusted as needed. Foam concrete, with its good properties, is applied to widen roadbed filling in road expansion, which can better solve the problem of differential deformation of old and new roadbeds, and can save land acquisition and avoid demolition.

The construction of foam concrete in the prior art often needs to excavate the roadbed and trim the steps, build the panel foundation, and then carry out synchronous construction of the prefabricated panel and the foam concrete. Although this traditional construction method uses foam concrete to improve the filling quality of the subgrade to a certain extent, the excavation volume of the subgrade is large during the construction process, and settlement at the bottom of the foam concrete backfill area cannot be avoided, and the connection between the old and new subgrades is not strong. Easy to crack and shift.

Therefore, there is an urgent need to seek a safe and stable construction method for effectively reducing the settlement of the newly widened roadbed and strengthening the connection between the old and new roadbeds.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art and provide a construction method for widening roadbed with anchor rod foam concrete.

This kind of anchor foam concrete widening subgrade includes leveling layer, drainage pipe, drainage ditch, water stop layer, support foundation, support, anchor group, hollow grouting anchor, inclined support rod, horizontal support rod, plain Concrete transition zone, inserting board, L-shaped baffle, anchor head, n-type foundation, foam concrete and horizontal lateral support rods, the n-type foundation is set at the bottom of the existing subgrade, and the hollow grouting anchor rod passes through The n-type foundation is set in the existing roadbed, the anchor head is set at the outer end of the hollow grouting anchor rod, the plain concrete transition zone is set between the existing roadbed slope and the n-type foundation, and the L-shaped retaining The plate is set on the n-shaped foundation, the insert plate is set on the L-shaped baffle plate, the bottom of the support foundation is provided with a group of anchor rods, and the support foundation and the group of anchor rods are arranged in the existing roadbed slope. The base of the support, the inserting plate, the L-shaped baffle and the n-shaped foundation are all provided with a support, and the inserting plate and the L-shaped baffle at the bottom are respectively provided with an inclined support rod between the n-shaped foundation, and the support There are oblique support rods, horizontal support rods and horizontal lateral support rods between the foundation and the inserting board, the foam concrete is arranged between the existing subgrade and the panel, the bottom of the drainage ditch is provided with a water-stop layer, and the drainage ditch is set Below the joint between the existing pavement layer and the new pavement layer, one end of the drainage pipe is connected to the drainage ditch, and the other end passes through the insert plate at the top, and the leveling layer is arranged between the new pavement layer and the foam concrete.

As a preference: the panel is composed of several boards and L-shaped baffles, steel sockets are provided at the top of the boards, steel plugs are provided at the bottom of the boards, steel sockets are provided at the top of the L-shaped baffles, Bolt holes are provided at the bottom of the L-shaped baffle, and the steel plug at the bottom of the plug-in board is connected with the steel socket at the top of the L-shaped baffle.

As a preference: the inside of the n-type foundation is provided with an obliquely downward anchor hole, the bottom of the n-type foundation is provided with two outriggers, the top of the n-type foundation is a wedge-shaped surface, a support is provided at the low end, and a support is provided at the high end. There are anchor bolts.

The construction method for widening the roadbed with anchor rod foam concrete comprises the following steps:

1) Clear the existing subgrade slope first, excavate a convex foundation pit at the base, then bind steel bars, pre-bury anchor bolts and reserve anchor holes in advance, and then pour concrete to form a reinforced concrete n-type foundation, The hollow grouted anchor is drilled into the existing subgrade through the anchor hole. After the hollow grouted anchor is grouted, the hollow grouted anchor and the n-type foundation are fixed together by the anchor head, and the n-type foundation and the existing Backfill plain concrete transition zone between subgrades;

2) First install the L-shaped baffle on the n-shaped foundation with anchor bolts, and fix the support on the L-shaped baffle and the n-shaped foundation, then install the inclined support rod between the supports, and install it according to the inserting plate The height of the anchor group is set on the existing roadbed slope, the support foundation is poured on the top of the anchor group, and the support is installed on the support foundation, and then the insert plate is installed on the L-shaped baffle, and the insert plate is installed on the insert plate. Install the support at the same height as the support on the base of the support, and finally install an oblique support rod between the insert plate and the support of the n-type foundation, and install horizontal support rods between the base of the support and the support of the insert plate and horizontal lateral struts;

3) After sealing and waterproofing between the inserting boards in the horizontal direction and the L-shaped baffles in the horizontal direction, take the horizontal support bar as the pouring dividing line, backfill and pour foam concrete between the existing roadbed and the panel, and then According to the height of the widening subgrade, continue to install the support foundation, inserting plate and support rod, and pour backfill foam concrete layer by layer until it reaches the design height;

4) First, chisel the overlapping edge of the existing pavement layer to form a hypotenuse, then excavate a trench under it, apply a water-stop layer at the bottom of the trench, and then construct a drainage ditch, and install and wrap geotextiles at intervals outside the drainage ditch Drainage pipes, the drainage pipes lead to the outside with a certain slope and pass through the top plate;

5) Finally, a leveling layer is poured above the backfilled foam concrete, and the new pavement layer is overlapped with the existing pavement layer to complete the construction of the anchor foam concrete widened roadbed.

The beneficial effects of the present invention are:

1. Compared with the traditional technology, the n-type foundation set by the present invention not only greatly reduces the amount of foundation excavation, but also effectively improves the bearing capacity of the base in the foam concrete backfill area, and uses hollow grouting anchors to strengthen the integrity of the existing roadbed , the technical benefit advantage is obvious.

2. The inserting plate and the L-shaped baffle provided in the present invention have a reasonable structure, are easy to manufacture and install, effectively improve the construction efficiency of the panel, and reduce the construction period.

3. The support and support rods provided in the present invention not only improve the integrity and rigidity of the panel, but also strengthen the connection between the old and new subgrades and reduce the settlement difference.

4. The drainage ditch provided in the present invention has a reasonable structure, effectively removes rainwater that may infiltrate at the junction of the new and old road surfaces, avoids harm to the junction of the old and new roadbeds, and ensures the filling quality of the roadbed.

Description of drawings

Fig. 1 is the schematic diagram of anchor bar foam concrete widened subgrade;

Figure 2 is a schematic cross-sectional view of an n-type foundation;

Figure 3 is a schematic diagram of the construction of an n-type foundation;

Fig. 4 is the schematic diagram of plug-in board unit;

Fig. 5 is a schematic diagram of an L-shaped baffle unit;

Figure 6 is a schematic diagram of the installation of the panel structure;

Fig. 7 is a plane layout diagram of the panel structure;

Fig. 8 is the schematic diagram of layered backfill of foamed concrete;

Figure 9 is a layout diagram of the drainage ditch.

Explanation of reference signs: 1—existing pavement layer; 2—new pavement layer; 3—leveling layer; 4—drainage pipe; 5—drainage ditch; 6—water stop layer; 7—support Foundation; 8—support; 9—anchor group; 10—hollow grouting anchor; 11—oblique support rod; 12—horizontal support rod; 13—plain concrete transition zone; 14—insert Plate; 15—L-shaped baffle; 16—anchor head; 17—n-type foundation; 18—steel socket; 19—bolt hole; 20—steel plug; 21—foam concrete; 22— Existing subgrade; 23—horizontal lateral support rod; 24—anchor bolt; 25—bolt hole; 26—outrigger.

Detailed ways

The present invention will be further described below in conjunction with the examples. The description of the following examples is provided only to aid the understanding of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, some improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Embodiment one

The anchor foam concrete widened subgrade includes leveling layer 3, drainage pipe 4, drainage ditch 5, water stop layer 6, support foundation 7, support 8, anchor group 9, hollow grouting anchor 10, Diagonal support rod 11, horizontal support rod 12, plain concrete transition zone 13, insert plate 14, L-shaped baffle plate 15, anchor head 16, n-type foundation 17, foam concrete 21 and horizontal lateral support rod 23, the n-type The foundation 17 is set at the bottom of the existing roadbed 22, the hollow grouting anchor 10 is set obliquely through the n-shaped foundation 17 and placed in the existing roadbed 22, and the anchor head 16 is set at the outer end of the hollow grouting anchor 10, The plain concrete transition zone 13 is arranged between the slope of the existing subgrade 22 and the n-shaped foundation 17, the L-shaped baffle 15 is arranged on the n-shaped foundation 17, and the insert plate 14 is arranged on the L-shaped baffle 15 Above, the bottom of the support foundation 7 is provided with an anchor group 9, and the support foundation 7 and the anchor group 9 are arranged in the slope of the existing roadbed 22, and the support foundation 7, the insert plate 14, and the L-shaped baffle 15 and n-type foundation 17 are all provided with bearing 8, and the inserting plate 14 of described bottom is connected with L-type baffle top and between L-type baffle 15 and n-type foundation 17, be provided with oblique support bar 11 respectively, so An oblique support rod 11, a horizontal support rod 12, and a horizontal lateral support rod 23 are arranged between the support foundation 7 and the insert plate 14. The foam concrete 21 is arranged between the existing subgrade 22 and the panel, and the drainage ditch 5 is provided with a water-stop layer 6 at the bottom, and the drainage ditch 5 is arranged below the junction of the existing pavement layer 1 and the new pavement layer 2. One end of the drainage pipe 4 is connected to the drainage ditch 5, and the other end passes through the top plate 14 Located at the new pavement layer, the leveling layer 3 is arranged between the new pavement layer 2 and the foamed concrete 21 .

As shown in Figure 4 and Figure 5, the panel is composed of several boards 14 and L-shaped baffles 15, the top of the board 14 is provided with a steel socket 18, and the bottom of the board 14 is provided with a steel plug 20, The top of the L-shaped baffle 15 is provided with a steel socket 18, the bottom of the L-shaped baffle 15 is provided with a bolt hole 19, and the steel plug 20 at the bottom of the plate 14 is connected with the steel socket 18 at the top of the L-shaped baffle 15.

As shown in Figure 2, the inside of the n-type foundation 17 is provided with an obliquely downward anchor hole 25, the bottom of the n-type foundation 17 is provided with two legs 26, the top of the n-type foundation 17 is a wedge-shaped surface, and the bottom of the n-type foundation 17 is a wedge-shaped surface. A bearing 8 is provided, and an anchor bolt 24 is provided at the high end.

Embodiment two

According to the construction method of anchor rod foam concrete widened subgrade, first construct n-type foundation, then install L-shaped baffles and insert plates in layers to form panels, and carry out backfilling and pouring of foam concrete in layers, and then apply road surface waterproofing and drainage Finally, the leveling layer is poured, the new pavement layer is applied, and the construction of the anchor foam concrete widened roadbed is completed. Specifically include the following steps:

1) As shown in Figure 3, first clear the slope of the existing subgrade 22, excavate a convex foundation pit at the base, and then bind steel bars, pre-buried the anchor bolts 24 and reserved anchor holes 25 in advance, and then poured The concrete forms the n-type foundation 17 of reinforced concrete, and the hollow grouting anchor 10 is laid on the existing subgrade 22 through the anchor hole 25. After the hollow grouting anchor 10 is grouted, the hollow grouting anchor 10 is screwed by the anchor head 16. Fix together with the n-type foundation 17, and backfill the plain concrete transition zone 13 between the n-type foundation 17 and the existing subgrade 22;

2) As shown in Fig. 6 and Fig. 7, the L-shaped baffle 15 is first installed on the n-shaped foundation 17 with the anchor bolt 24, and the support 8 is fixedly installed on the L-shaped baffle 15 and the n-shaped foundation 17, Then oblique support rods 11 are installed between the bearings 8, and at the same time according to the installation height of the board 14, the anchor group 9 is laid on the existing roadbed 22 slope, and the support foundation 7 is poured on the top of the anchor group 9, and the support is installed on the support. Install the support 8 on the foundation 7, then install the flashboard 14 on the L-shaped baffle plate 15, and install the support 8 on the flashboard 14, and the same height as the support 8 on the support foundation 7, and finally install it on the flashboard 14 and the support 8 of the n-type foundation 17 are installed with oblique support rods 11, and horizontal support rods 12 and horizontal lateral support rods 23 are respectively installed between the support base 7 and the support 8 of the flashboard 14;

3) As shown in Figure 8, after sealing and waterproofing are done between the inserting plates 14 in the horizontal direction and the L-shaped baffles 15 in the horizontal direction, the horizontal support bar 12 is used as the pouring dividing line, and the existing roadbed 22 Backfill and pour foam concrete 21 between the face plate, and then continue to install the support foundation 7, insert plate 14 and support rods according to the height of the widened embankment, and pour backfill foam concrete 21 layer by layer until the design height;

4) As shown in Figure 9, firstly chisel the overlapping edge of the existing pavement layer 1 to form a hypotenuse, then excavate a trench below it, and apply a water stop layer 6 at the bottom of the trench, and then construct a drainage ditch 5, Drainage pipes 4 wrapped with geotextiles are installed at intervals on the outside of the drainage ditch 5, and the drainage pipes 4 lead to the outside with a slope of 3% and pass through the top plate 14;

5) As shown in Figure 1, a leveling layer 3 is poured above the backfilled foam concrete 21, and the new pavement layer 2 is overlapped with the existing pavement layer 1 to complete the construction of the anchor bar foam concrete widened roadbed.

Claims (1)

1. a kind of construction method of bolt foam concrete spells wide subgrade, is characterized in that, comprises the following steps: 1) Clear the slope of the existing subgrade (22) first, excavate a convex foundation pit at the base, then bind steel bars, pre-bury the anchor bolts (24) and reserve anchor holes (25) in advance, and then pour Concrete forms the n-type foundation (17) of reinforced concrete, lays hollow grouting anchor (10) to existing subgrade (22) by anchor hole (25), after hollow grouting anchor (10) grouting, utilize The anchor head (16) fixes the hollow grouting anchor (10) and the n-type foundation (17), and backfills the plain concrete transition zone (13) between the n-type foundation (17) and the existing subgrade (22). ); 2) First install the L-shaped baffle (15) on the n-shaped foundation (17) with the anchor bolts (24), and fix the mounting support on the L-shaped baffle (15) and the n-shaped foundation (17) ( 8), then install the inclined support rods (11) between the supports (8), and set the anchor group (9) on the slope of the existing subgrade (22) according to the installation height of the insert plate (14). Group (9) top pouring support foundation (7), and support (8) is installed on the support foundation (7), then inserting plate (14) is installed on the L-shaped baffle plate (15), and on the inserting plate Install the support (8) on (14), and the same height as the support (8) on the support foundation (7), finally between the support (8) of the plate (14) and the n-type foundation (17) The oblique support rod (11) is installed, and the horizontal support rod (12) and the horizontal lateral support rod (23) are respectively installed between the support base (7) and the support (8) of the plate (14); 3) After sealing and waterproofing between the inserting plates (14) in the horizontal direction and the L-shaped baffles (15) in the horizontal direction, the horizontal support rod (12) is used as the pouring dividing line, and the existing subgrade ( 22) and backfill the foam concrete (21) between the panels, and then continue to install the support foundation (7), inserting plate (14) and support rods according to the height of the widened roadbed, and pour the backfill foam concrete (21) layer by layer until design height; 4) Firstly chiseling the overlapped edge of the existing pavement layer (1) to form a hypotenuse, then excavating a trench below it, applying a water stop layer (6) at the bottom of the trench, and then constructing a drainage ditch (5), Drainage pipes (4) wrapped with geotextiles are installed at intervals on the outside of the drainage ditch (5), and the drainage pipes (4) lead to the outside with a certain slope and pass through the top plate (14); 5) Finally, a leveling layer (3) is poured on top of the backfilled foam concrete (21), and a new pavement layer (2) is overlapped with the existing pavement layer (1) to complete the construction of the anchor foam concrete widening subgrade.

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