A construction method of embedded anchor structure for reducing foundation pit excavation volume

Abstract

The invention relates to the field of foundation pit excavation, and discloses an embedded anchor structure construction method for reducing the amount of foundation pit excavation, comprising the following steps: step 1, preparing an embedded component and a steel cage, installing the embedded component on the main reinforcement of the steel cage; an operating chamber is provided in the embedded component, a drilling hole is provided on one side of the embedded component close to the center of the steel cage, and the drilling hole is used for the drilling tool to pass through; step 2, placing the steel cage in the pile hole, and pouring pile body concrete; step 3, excavating the foundation pit, finding the embedded component, drilling an anchor hole at the drilling hole position, placing an anchor cable in the anchor hole, and grouting the anchor hole; step 4, placing a pressure-bearing part and an anchor on the drilling hole in sequence, wherein the outer diameter of the pressure-bearing part is larger than the drilling hole, a first accommodating hole is provided on the pressure-bearing part, and the inner diameter of the first accommodating hole is smaller than the anchor, a steel cable passes through the drilling hole, the first accommodating hole and the anchor in sequence, tensioning the anchor cable, and sealing the anchor. The filling layer of the fertilizer trough is eliminated, the foundation pit excavation is reduced, the environment is protected, and the method is green, energy-saving and low-carbon.

Description

Technical Field

[0001] The invention relates to the field of foundation pit excavation, and in particular to a construction method of an embedded anchor structure for reducing the amount of foundation pit excavation. Background Art

[0002] The foundation pit is used for the foundation construction of construction projects or municipal projects. Generally, the larger the building structure, the larger the foundation and the larger the foundation pit required. When the foundation pit support structure adopts the pile + anchor cable support type, it is necessary to first use a drill to drill a hole on the pile body at an angle of 15° to 25°, and then put the anchor cable in the hole for prestressing. To facilitate the tensioning construction of the anchor cable, the anchor is generally located on the outside of the pile body, and reinforced concrete or steel inclined supports (external anchor heads) are placed between the anchor and the pile body. The height of the reinforced concrete and steel inclined supports is 400-600mm. After tensioning, numerous protrusions are formed on the side walls of the foundation pit; on the other hand, in order to facilitate the pasting of the external waterproof layer on the side walls of the foundation pit, it is also necessary to use sprayed concrete, brick walls and other measures to lay the aforementioned protrusions flat.

[0003] The above measures will form a fertilizer trough filling layer with a width of 450 to 600 mm between the retaining piles and the outer wall of the underground main structure. Before excavation, it is necessary to consider in advance the inclusion of the fertilizer trough filling layer in the excavation volume. For large foundation pits with a circumference of hundreds of meters, it is necessary to increase the excavation of thousands of cubic meters and a large amount of support costs. Not only does it increase the investment and construction period, but there are also greater risks in its high-altitude operations (usually after the excavation is completed, scaffolding is erected for operation), and it also increases the pollution and damage to the surrounding rock and soil, which is not conducive to protecting the environment, green energy conservation and low carbon, and achieving sustainable development of urban construction. Summary of the invention

[0004] The present invention aims to provide an embedded anchor structure construction method for reducing the amount of foundation pit excavation, so as to eliminate the fertilizer trough filling layer, reduce foundation pit excavation, protect the environment, and be green, energy-saving and low-carbon.

[0005] To achieve the above object, the present invention adopts the following technical solution: a construction method of an embedded anchor structure for reducing the amount of foundation pit excavation, comprising the following steps:

[0006] Step 1: prepare an embedded component and a steel cage, and install the embedded component on the main reinforcement of the steel cage; an operating cavity is provided in the embedded component, and a drilling hole is opened on one side of the embedded component close to the center of the steel cage, and the drilling hole is used for the drilling tool to pass through;

[0007] Step 2: Place the steel cage into the pile hole and pour the pile concrete;

[0008] Step 3: excavate the foundation pit, find the embedded parts, drill anchor holes at the drilling openings, put anchor cables in the anchor holes, and grout the anchor holes;

[0009] Step 4: Place the pressure-bearing part and the anchor on the drill hole in sequence. The outer diameter of the pressure-bearing part is larger than the drill hole. The pressure-bearing part is provided with a first accommodating hole. The inner diameter of the first accommodating hole is smaller than the anchor. The steel cable passes through the drill hole, the first accommodating hole and the anchor in sequence, tension the anchor cable, and seal the anchor.

[0010] The beneficial effects of this program are:

[0011] 1. The embedded components are pre-buried in the pile body. After forming, the anchor heads are completely embedded in the surrounding pile body, thus solving the raised structure formed by the traditional external anchor head, thereby eliminating the fertilizer trough filling layer, reducing foundation pit excavation, protecting the environment, and being green, energy-saving and low-carbon.

[0012] 2. In the prior art, in order to facilitate operation, drilling and installation of embedded components, it is usually adopted to drill holes first and then install the embedded components. The embedded components do not need to consider the passability of the drill bit, which has become a common practice. However, in this scheme, in order to reduce excavation, the construction process is changed. The embedded components are first embedded in the pile body in advance, and then the anchor holes are drilled. Therefore, the embedded components need to consider the passability of the drill bit, and a drilling opening is set on the embedded components in advance for the drilling rig to pass through, so as to drill holes.

[0013] 3. Since the borehole opening is usually large, the anchor cannot directly cover the borehole. Therefore, after the anchor cable is tensioned, the anchor cable tension cannot be directly transferred to the steel support through the anchor. In this solution, a pressure-bearing part is set between the anchor and the base plate to transfer the anchor cable tensioning force to the steel support and disperse it to the pile body around the steel support to reduce concentrated stress; at the same time, it also prevents the steel strand or anchor cable from slipping or deviating from the predetermined path during the tensioning process.

[0014] 4. In this solution, the pressure-bearing parts and the steel support are not connected before pouring the pile body. Instead, the pressure-bearing parts are installed after pouring the pile body, thereby making the structure of the operating cavity in the steel support simple and flat. In order to prevent concrete from flowing into the operating cavity and facilitate cleaning of the operating cavity after pouring the pile body, an easy-to-clean foaming material can be filled in the operating cavity.

[0015] Furthermore, the drilling hole is arranged on the steel support base, and the drilling hole is arranged on the base; the pressure bearing member is a universal adjustment device, and the universal adjustment device includes a top plate and a bottom plate, and the contact surfaces of the top plate and the bottom plate are a convex spherical surface and a concave spherical surface that match each other, and the convex spherical surface and the concave spherical surface are connected by sliding and rotating, and the contact surface between the bottom plate and the base, and the contact surface between the top plate and the anchor are all planes;

[0016] In step 4, the top plate and the bottom plate are relatively rotated along the spherical surface so that the inclination angle of the anchor on the top plate is consistent with the design.

[0017] Furthermore, the embedded component includes a curved panel and a base, and a plurality of crossed transverse ribs and vertical ribs are provided on one side of the curved panel close to the center of the pile body.

[0018] Furthermore, the transverse ribs and the vertical ribs divide the inner side of the curved panel into several areas, the base covers one of the areas, and the base, the transverse ribs and the vertical ribs enclose to form an operating cavity.

[0019] Furthermore, a plurality of reserved holes are provided on one side of the transverse rib plate close to the curved panel, and the reserved holes at different heights are vertically aligned;

[0020] In step 1, the method for installing the embedded component on the main reinforcement of the reinforcement cage is: the main reinforcement of the reinforcement cage is passed through the reserved hole and fixedly connected with the curved panel.

[0021] Furthermore, an operating opening is provided on the curved panel, and a projection of the operating opening on the base covers the drilling opening;

[0022] In step 2, the positioning tube and filler are prepared, the positioning tube and the drilling hole are gap-matched, and before the pile body is poured, the positioning tube passes through the drilling hole and the operating hole and is inserted into the side wall of the pile hole to fill the operating cavity.

[0023] Furthermore, in step three, the foundation pit is excavated to the depth of the embedded component, the concrete on the surface of the pile body is broken until the operating port is exposed, the filler in the operating cavity is taken out, and the part of the positioning tube that is exposed outside the concrete is cut.

[0024] Furthermore, in step 2, a protective layer thickness of concrete is left between the curved panel and the side wall of the pile hole.

[0025] Furthermore, the embedded component also includes a grouting pipe and a guide pipe, the guide pipe is arranged on one side of the base close to the center of the steel cage and is connected to the drilling hole, one end of the grouting pipe passes through the arc panel, and the other end of the grouting pipe is connected to the guide pipe;

[0026] In step 4, after sealing the anchor, mortar is injected into the anchor hole through the grouting pipe until the pressure in the anchor hole reaches the design pressure.

[0027] Furthermore, the base is plate-shaped, and the upper part of the base is inclined toward the center of the steel cage, and the base forms an angle of 15°-25° with the vertical plane.

[0028] This solution also has the following effects:

[0029] 1. To prevent the steel cage from tilting toward the side with the embedded components, the steel bars of the steel cage near the curved panel are too close to the side wall of the pile hole, and the concrete cannot completely bury the steel bars, which makes the steel bars easy to rust and age. In this solution, a protective layer thickness is ensured between the curved panel and the side wall of the pile hole, so that the steel cage near the curved panel can be protected by the concrete, thereby improving the durability of the steel cage.

[0030] 2. Since the steel support in this solution is pre-buried on the pile body and the steel cage, when the pile concrete is poured, the flowing concrete will form a large buoyancy on the steel support. During the concrete pouring and vibration process, the steel support may be displaced or floated, which may cause the direction and angle of the anchor cable tension to deviate.

[0031] In this regard, this scheme sets a universal adjustment device between the anchor and the pressure plate. Through the convex spherical surface and the concave spherical surface, the top plate can slide arbitrarily along the spherical surface, thereby driving the anchor to rotate along the center of the spherical surface, so that the angle of the anchor is consistent with the design angle, so as to coordinate the construction errors and ensure that the anchor cable forming angle is consistent with the design.

[0032] 3. According to relevant operating specifications, when pouring concrete for the pile body, a conduit is required to guide the flowing concrete to pour downwards. As the concrete pouring height increases, the conduit is also pulled upwards. However, since the steel support pre-buried in the pile body occupies part of the concrete pouring space, the conduit is easily collided with or stuck by the steel support during the upward pulling process and cannot be pulled up, delaying the concrete pouring and leading to the risk of pile scrapping such as broken piles.

[0033] In the present solution, the upper part of the base is inclined at an angle of 15-25° toward the center of the pile body, that is, the entire embedded component is close to the center side of the pile body, the lower part is narrower, and the upper part is wider, forming a wedge-shaped transition effect, which can prevent the conduit connection flange from being stuck by the device and unable to be pulled up under the squeezing effect of liquid concrete, thereby avoiding the risk of the pile body being scrapped.

[0034] 4. This scheme sets reserved holes between the transverse ribs and the curved panels. Each reserved hole corresponds to a main reinforcement and is located on the same straight line, so that the main reinforcement can be welded to the inner side of the curved panel after the corresponding main reinforcement passes through. Multiple main reinforcements are passed through the transverse ribs and the inner side of the curved panel of the embedded component, and the penetrated main reinforcements are welded to the curved panel of the component, so that the component and the pile body steel cage are integrated, which can ensure the accurate positioning of the embedded components, facilitate the corresponding depth of the foundation pit excavation in the later stage, and make up for the strength of the embedded components embedded in the pile body concrete.

[0035] 5. In the prior art, the anchor head is arranged outside the pile body, and the tension of the anchor cable diffuses to the whole pile body through the outside of the pile body; however, when the embedded component is pre-buried inside the pile body, if the tension of the anchor cable acts directly inside the pile body, the diffusion radiation range of the tension of the anchor cable is reduced, the force-bearing structure is deteriorated, and the pressure generated by the tension of the anchor cable on the pile body is increased, which is easy to cause the pile body to crack;

[0036] In this scheme, curved panels, bases, transverse ribs and vertical ribs are arranged. The anchor cable tension first acts on the base through the anchor and the pressure plate, then is transmitted to the curved panels through the transverse ribs and the vertical ribs, and then is transmitted to the pile reinforcement and surface concrete through the curved panels. This ensures that the force transmission mechanism between the formed anchor head and the pile body is consistent with that of the traditional external anchor head, thereby ensuring the safety of the overall enclosure structure.

[0037] 6. In the actual construction process, the pile hole is usually slightly larger than the design size to facilitate the installation of the steel cage. However, this also easily leads to the embedded components in some positions being buried deeper into the pile body, making it difficult to find them during the excavation of the foundation pit. When the embedded components are dug out from the surface of the pile body, the volume of the pile body to be broken is easily increased, increasing the damage to the pile body, thereby reducing the overall structural stability of the pile body;

[0038] In this regard, the present invention can arrange circumferential positioning reinforcement steel bars on the periphery of the reinforcement cage in the embedded component area. The circumferential positioning reinforcement steel bars are welded on the outside of the curved panel. The outer circumferential reinforcement steel bars are easy to be found, so that the staff can quickly find the position of the embedded component.

[0039] During the concrete pouring process, the conduit is buried about 5m below the poured concrete. After the subsequent concrete is poured into the poured concrete through the conduit, it diffuses from the bottom of the conduit to the surrounding area and then emerges upward in the opposite direction. Although this method uses the concrete's own weight to squeeze and compact it, reducing the vibration of the pile concrete, it also produces a floating and lateral squeezing effect on the steel cage and embedded components during the upward emergence of the concrete. Therefore, the second fixation is to reduce the gap between the embedded components and the steel cage and the side wall of the pile hole by strengthening the positioning stirrups in the annular direction, reducing the impact of concrete pouring, thereby ensuring the position accuracy of the embedded components, and then ensuring that the tensioning direction of the anchor cable is consistent with the design, so as to achieve the best force effect.

[0040] In addition, the annular reinforcement positioning stirrups can ensure that there is a certain distance between the steel cage and the side wall of the borehole, thereby meeting the protective layer thickness requirements of the steel cage in the specification and preventing the steel cage from shaking close to the side wall of the borehole during the concrete pouring process, thereby making the local concrete protective layer too thin and affecting the durability of the pile body.

[0041] 7. For foundation pits supported by piles + anchor cables, the surrounding rock is usually relatively weak. Therefore, after the steel cage is placed in the pile hole and positioned, the positioning cylinder is inserted into the side wall of the pile hole (i.e., the surrounding rock) after passing through the drilling port and the operating port to perform secondary positioning of the embedded components. On the one hand, the positional deviation of the embedded components during concrete pouring is reduced, and on the other hand, the part of the positioning cylinder inserted into the side wall of the pile hole will not be buried by the concrete structure, thereby ensuring that the positioning cylinder is easy to be found after the foundation pit is excavated, so that the staff can quickly find the position of the embedded components; after finding the embedded components, the positioning cylinder needs to be removed to facilitate the installation of the universal adjustment device and the anchor, so the positioning cylinder is usually made of plastic or other materials that are easy to cut, and the filler in the operating cavity is cleared. The filler is usually made of flexible materials such as foam plastic, and the hardness of the flexible material is usually lower than that of the positioning cylinder.

[0042] The objects of the two positioning of the embedded component are different. The first time the embedded component is fixed on the steel cage, and its purpose is to use the steel cage as an anchor to fix the relative position of the embedded component and the steel cage; the second time the embedded component is fixed on the side wall of the pile hole through the positioning tube, and its purpose is to use the side wall of the pile hole as an anchor to fix the relative position of the embedded component and the steel cage, thereby achieving the effect of double positioning.

[0043] In fact, the second fixing method is less affected by the offset of concrete pouring. Specifically, during the concrete pouring process, the concrete enters the steel cage through the conduit. At this time, the concrete flow rate is relatively large, and the impact on the steel cage is relatively large. Then, the concrete is buffered by the steel cage and fills the position between the steel cage and the side wall of the pile hole. Due to the small space at this position, it is not convenient for operators to directly insert a vibrating rod for vibration. Most of the time, the concrete is vibrated in the steel cage and then flows to the outside of the steel cage, making the concrete more compact. Therefore, the second fixing of the embedded component is to insert the positioning cylinder into the side wall of the pile hole for fixing. The main fixing position is on the side wall of the pile hole, which is less affected by concrete pouring, so as to ensure the position accuracy of the embedded component, and then ensure that the tensioning direction of the anchor cable is consistent with the design, so as to achieve the best force effect.

[0044] In addition, the positioning tube can ensure that there is a certain distance between the steel cage and the side wall of the borehole, thereby meeting the protective layer thickness requirements of the steel cage in the specification and preventing the steel cage from shaking close to the side wall of the borehole during the concrete pouring process, thereby making the local concrete protective layer too thin and affecting the durability of the pile body.

[0045] 8. After the main reinforcement of the steel cage passes through the inside of the transverse ribs and the curved panel and is welded, the transverse ribs and the curved panel are fixed more firmly. The base is directly connected to the transverse ribs and the curved panel to ensure the stability of the base, while the vertical ribs are not directly connected to the main reinforcement and are relatively weak in firmness. Therefore, compared with the connection with the vertical ribs, the connection between the base and the curved panel is more stable.

[0046] 9. After the bottom plate and top plate of the universal adjusting device are adjusted to the appropriate angle, the pressure brought by the tension of the anchor cable presses the bottom plate, top plate and embedded components tightly, thereby automatically achieving the effect of fixing the angle of the universal adjusting device, which is convenient and quick. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a schematic diagram of an external anchor head in the prior art;

[0048] Figure 2 is a flow chart of Example 1;

[0049] Figure 3 This is a schematic diagram of the installation of the embedded component in step 1 of Example 1 on the steel cage;

[0050] Figure 4 A three-dimensional axonometric diagram of the embedded component, the pressure-bearing component and the anchor in step 4 of Example 1;

[0051] Figure 5 for Figure 4 3D axonometric drawing after removing the curved panel;

[0052] Figure 6 for Figure 4 Exploded diagram of the structure;

[0053] Figure 7 It is a three-dimensional axonometric diagram of the universal adjustment device of Example 2;

[0054] Figure 8 It is a three-dimensional cross-sectional view of the universal adjustment device of Example 2;

[0055] Fig. 9 This is a three-dimensional axonometric drawing of Example 3. DETAILED DESCRIPTION

[0056] The following is further described in detail through specific implementation methods:

[0057] The figure marks in the drawings of the specification include: anchor 11, external anchor head 12, anchor cable 13, anchor hole 14, pile body 15, steel cage 16, curved panel 2, operating port 21, operating cavity 22, transverse ribs 23, vertical ribs 24, reserved holes 25, pressure-bearing part 3, first accommodating hole 31, bottom plate 33, top plate 32, second accommodating hole 34, spherical surface 35, base 4, drilling port 41, grouting pipe 5, guide pipe 6.

[0058] Example 1

[0059] Example 1 is basically as Figure 2-Figure 6 As shown: A construction method of embedded anchor structure for reducing foundation pit excavation volume, based on Figure 1 The anchor head of the prior art shown in the figure is improved. In the foundation pit with the traditional pile anchor support structure, an external anchor head 12 is provided on the outside of the pile body 15, and the anchor hole 14 and the anchor cable 13 pass through the pile body 15 and enter the surrounding rock on the right side of the pile body 15. The anchor 11 anchors the left end of the anchor cable 13 on the external anchor head 12. The flow chart of this embodiment 1 is as shown in FIG. Figure 2 As shown, Example 1 includes the following steps:

[0060] Step 1: Prepare the embedded components and the steel cage 16, such as Figure 4 , Figure 5 As shown in the figure, the right side is the center direction of the pile body 15, and an operating cavity 22 is provided in the embedded component. The embedded component includes a curved panel 2 and a base 4. A plurality of cross-shaped transverse ribs 23 and vertical ribs 24 are welded on the side of the curved panel 2 close to the center of the pile body 15. Figure 5As shown, the transverse ribs 23 and the vertical ribs 24 divide one side of the embedded component into several areas, the base 4 covers the area at the center, and the base 4, the transverse ribs 23 and the vertical ribs 24 enclose the operating chamber 22. Figure 5 As shown, the left side of the transverse rib 23 is an arc shape that matches the inner shape of the arc plate, and the right side of the transverse rib 23 is a straight line shape that matches the shape of the base 4; a plurality of reserved holes 25 are opened on the left side of the transverse rib 23, and the reserved holes 25 of different heights are vertically aligned, and the reserved holes 25 are used for the main reinforcement of the steel cage 16 to pass through.

[0061] like Figure 6 As shown, the base 4 is a rectangular plate, the upper part of the base 4 is inclined toward the center of the pile body 15, and the base 4 forms an angle of 15°-25° with the vertical plane; a drilling opening 41 is opened on the base 4, and the drilling opening 41 is used for the drilling tool to pass through, and an operating opening 21 is opened on the curved panel 2, and the projection of the operating opening 21 on the base 4 covers the drilling opening 41, and the operating cavity 22 is respectively connected with the operating opening 21 and the drilling opening 41.

[0062] like Figure 5 , Figure 6 As shown, a pressure-bearing member 3 and an anchor 11 are sequentially arranged on the side of the drilling hole 41 close to the operating chamber 22. The outer diameter of the pressure-bearing member 3 is larger than that of the drilling hole 41. A first receiving hole 31 is opened on the pressure-bearing member 3. The inner diameter of the first receiving hole 31 is smaller than that of the anchor 11. The first receiving hole 31 is used for the anchor cable 13 to pass through. The sizes of the anchor cable 11 and the anchor cable 13 are adapted.

[0063] like Figure 3 As shown, the main bars of the steel cage 16 are passed through the reserved holes 25 and welded to the inner side of the curved panel 2, and these main bars are used to bind and make the steel cage 16, so as to achieve the effect of installing the embedded component on the main bars of the steel cage 16;

[0064] Step 2: Install the embedded components at the specified position of the steel cage, fill the operating cavity 22 of the embedded components with foam plastic, put the steel cage 16 into the pile hole, and face the side with the embedded components to the foundation pit to be excavated, check the verticality and plane position of the main reinforcement, the thickness of the protective layer of concrete left between the curved panel 2 and the side wall of the pile hole, and pour the concrete of the pile body 15;

[0065] Step 3: excavate the foundation pit, remove the soil near the foundation pit of the pile body 15, find the embedded component, drill the anchor hole 14 at the position of the drilling hole 41, put the anchor cable 13 into the anchor hole 14, and grout the anchor hole 14;

[0066] Step 4: Place the pressure-bearing part 3 and the anchor 11 on the drill hole 41 in sequence. The outer diameter of the pressure-bearing part 3 is larger than the drill hole 41. The pressure-bearing part 3 is provided with a first accommodating hole 31. The inner diameter of the first accommodating hole 31 is smaller than the anchor 11. The steel cable passes through the drill hole 41, the first accommodating hole 31 and the anchor 11 in sequence, tensions the anchor cable 13, and seals the anchor.

[0067] Example 2

[0068] The difference between Example 2 and Example 1 is that the pressure bearing member 3 is a universal adjustment device, such as Figure 7 As shown, the universal adjustment device includes a top plate 32 and a bottom plate 33. Figure 8 As shown, both the top plate 32 and the bottom plate 33 are disc-shaped. Depending on the situation, the diameter of the bottom plate 33 can be larger than the diameter of the top plate 32 (not shown in the figure). A second receiving hole 34 is respectively opened on the top plate 32 and the bottom plate 33. The second receiving hole 34 is used for the anchor cable 13 to pass through. The contact surfaces of the top plate 32 and the bottom plate 33 are a convex spherical surface 35 and a concave spherical surface 35 that match each other. The convex spherical surface 35 is arranged on the bottom plate 33, and the concave spherical surface 35 is arranged on the top plate 32. Before tensioning the anchor cable 13, the convex spherical surface 35 and the concave spherical surface 35 are connected by sliding and rotation, that is, the top plate 32 can slide arbitrarily along the spherical surface 35, driving the anchor 11 to rotate along the center of the second receiving hole 34 of the bottom plate 33;

[0069] After pouring the pile body 15, the right side of the bottom plate 33 is welded to the base 4, the center of the second accommodating hole 34 of the bottom plate 33 and the drilling hole 41 of the base 4 are coaxial, the left side of the top plate 32 supports the anchor 11, and the contact surface between the bottom plate 33 and the base 4 and the contact surface between the top plate 32 and the anchor 11 are both planes.

[0070] In step four, the top plate 32 and the bottom plate 33 rotate relative to each other along the spherical surface 35 so that the inclination angle of the anchor 11 on the top plate 32 is consistent with the design. After the anchor cable 13 is tensioned, the pressure brought by the tension of the anchor cable 13 presses the bottom plate 33, the top plate 32 and the steel support, thereby fixing the angle of the universal adjustment device.

[0071] Example 3

[0072] The difference between Example 3 and Example 2 is that: Fig. 9 As shown, the steel support also includes a grouting pipe 5 and a guide pipe 6. The guide pipe 6 is horizontally welded to the right side of the base 4. The left end of the guide pipe 6 is connected to the drilling hole 41. The grouting pipe 5 is L-shaped. The left end of the grouting pipe 5 passes through the curved panel 2. The lower end of the grouting pipe 5 is connected to the guide pipe 6.

[0073] The curved panel 2 is vertically arranged, the base 4 and the curved panel 2 form an angle of 15°-25°, the two sides of the base 4 are connected to the two sides of the curved panel 2, and the base 4, the transverse ribs 23 and the curved panel 2 enclose an operating cavity 22.

[0074] In step 4, after sealing the anchor, mortar is injected into the anchor hole 14 through the grouting pipe 5 until the pressure in the anchor hole 14 reaches the design pressure. Under the design pressure, the mortar fills the anchor hole 14 and will not rush out from the anchor 11 and the grouting pipe 5.

[0075] Example 4

[0076] Example 4 is based on Example 1, Example 2 or Example 3: the steel support also includes a positioning tube, the positioning tube and the drilling hole 41 are clearance-matched, the positioning tube is used to pass through the drilling hole 41 and the operating port 21 and then be inserted into the side wall of the pile hole, and the filler is filled in the positioning tube and between the positioning tube and the operating cavity 22.

[0077] In step two, prepare the positioning tube and the filler, the positioning tube and the drilling opening 41 are clearance-matched, before pouring the pile body 15, chisel open the retaining wall at the location of the operating opening 21 of the embedded component on the pile hole to expose the soft surrounding rock behind the retaining wall, and the positioning tube is inserted into the soft surrounding rock of the pile hole side wall after passing through the drilling opening 41 and the operating opening 21, and the filler is filled in the space between the positioning tube and the operating cavity 22.

[0078] In step three, the foundation pit is excavated to the depth of the embedded components, the surface concrete of the pile body 15 is broken until the operating port 21 is exposed, the operating cavity 22 and the filler in the positioning tube are taken out, and the part of the positioning tube that is exposed outside the concrete is cut.

[0079] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for constructing an embedded anchor structure for reducing the amount of foundation pit excavation, characterized in that: The following steps are involved: Step 1: prepare an embedded component and a steel cage, and install the embedded component on the main reinforcement of the steel cage; an operating cavity is provided in the embedded component, and a drilling hole is opened on one side of the embedded component close to the center of the steel cage, and the drilling hole is used for the drilling tool to pass through; Step 2: Place the steel cage into the pile hole and pour the pile concrete; Step 3: excavate the foundation pit, find the embedded parts, drill anchor holes at the drilling openings, put anchor cables in the anchor holes, and grout the anchor holes; Step 4: Place a pressure-bearing member and an anchor on the borehole in sequence, wherein the outer diameter of the pressure-bearing member is larger than the borehole, a first receiving hole is provided on the pressure-bearing member, and the inner diameter of the first receiving hole is smaller than the anchor, and the steel cable passes through the borehole, the first receiving hole and the anchor in sequence, tensioning the anchor cable and sealing the anchor; The embedded component includes a base, and the drilling hole is set on the base; the pressure-bearing member is a universal adjustment device, and the universal adjustment device includes a top plate and a bottom plate, and the contact surfaces of the top plate and the bottom plate are a convex spherical surface and a concave spherical surface that match each other, and the convex spherical surface and the concave spherical surface are connected by sliding and rotating, and the contact surface between the bottom plate and the base, and the contact surface between the top plate and the anchor are all planes; In step 4, the top plate and the bottom plate are relatively rotated along the spherical surface so that the inclination angle of the anchor on the top plate is consistent with the design.

2. The method for constructing an embedded anchor structure for reducing the amount of foundation pit excavation according to claim 1, characterized in that: The embedded component comprises an arc-shaped panel and a base. A plurality of intersecting transverse ribs and vertical ribs are arranged on one side of the arc-shaped panel close to the center of the pile body.

3. The method for constructing an embedded anchor structure for reducing the amount of foundation pit excavation according to claim 2, characterized in that: The transverse ribs and the vertical ribs divide the inner side of the curved panel into several areas, the base covers one of the areas, and the base, the transverse ribs and the vertical ribs enclose an operating cavity.

4. The method for constructing an embedded anchor structure for reducing the amount of foundation pit excavation according to claim 3, characterized in that: A plurality of reserved holes are provided on one side of the transverse rib plate close to the curved panel, and the reserved holes at different heights are vertically aligned; In step 1, the method for installing the embedded component on the main reinforcement of the reinforcement cage is: the main reinforcement of the reinforcement cage is passed through the reserved hole and fixedly connected with the curved panel.

5. The method for constructing an embedded anchor structure for reducing the amount of foundation pit excavation according to claim 2, characterized in that: An operating opening is provided on the curved panel, and the projection of the operating opening on the base covers the drilling opening; In step two, prepare the positioning tube and filler, the positioning tube and the drilling hole are clearance-matched, and before the pile body is poured, the positioning tube passes through the drilling hole and the operating hole and is inserted into the side wall of the pile hole to fill the space between the positioning tube and the operating cavity with filler.

6. The method for constructing an embedded anchor structure for reducing the amount of foundation pit excavation according to claim 5, characterized in that: In step three, the foundation pit is excavated to the depth of the embedded component, the concrete on the surface of the pile body is broken until the operating port is exposed, the filler in the operating cavity is taken out, and the part of the positioning tube that is exposed outside the concrete is cut.

7. The method for constructing an embedded anchor structure for reducing the amount of foundation pit excavation according to claim 2, characterized in that: In step 2, a protective layer thickness of concrete is left between the curved panel and the side wall of the pile hole.

8. The method for constructing an embedded anchor structure for reducing the amount of foundation pit excavation according to claim 2, characterized in that: The embedded component also includes a grouting pipe, one end of which passes through the curved panel, and the other end of which is connected to the guide pipe; In step 4, after sealing the anchor, mortar is injected into the anchor hole through the grouting pipe until the pressure in the anchor hole reaches the design pressure.

9. The method for constructing an embedded anchor structure for reducing the amount of foundation pit excavation according to claim 2, characterized in that: The base is plate-shaped, and the upper part of the base is inclined toward the center of the steel cage. The angle between the base and the vertical plane is 15°-25°.

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