A road shoulder steep slope combined support structure and construction method thereof

Abstract

The present invention provides a shoulder steep slope joint retaining structure, which belongs to the field of slope protection technology, and mainly includes a lattice beam embedded and fixed on the mountain slope surface, and retaining walls connected to the lattice beam and respectively arranged at the top and bottom of the mountain slope. The retaining wall located at the top of the slope is an anchor pile retaining wall, and the anchor pile foundation of the anchor pile retaining wall is connected to the top beam of the lattice beam, and the anchor rod of the anchor pile foundation is inserted downward into the rock mass, and the anchor pile retaining wall and the lattice beam are each fixed to the rock mass through a plurality of anchor rods pulled obliquely downward; a drainage hole is arranged in the anchor pile retaining, and the drainage hole is arranged obliquely downward toward the outer surface. The present invention can effectively prevent landslides, is safe and reliable, and has good construction economy, simple process, and rapid construction.

Description

Technical Field

[0001] The present invention relates to the technical field of slope protection construction, and in detail, the present invention mainly relates to a road shoulder steep slope combined retaining structure and a construction method thereof. Background Art

[0002] During the construction of mountain roads, due to terrain restrictions, there is not enough space to widen the roadbed, and no space is reserved for peripheral ditches. During heavy rainfall, rainwater will penetrate from the slope into the cracks in the soil, which will cause the soil strength to decrease, making the roadbed soft or even hollowed out, thus causing landslides. The high and steep slopes formed by the collapse of the shoulder pose a threat to road traffic safety and the personal safety of pedestrians. Therefore, effective measures need to be taken to solve the problems of shoulder collapse and high and steep slope sliding to ensure the safety and passability of the road.

[0003] At present, common reinforcement measures for slopes at the shoulder of mountain roads include slope reduction, retaining wall support, and anti-slide piles. Among them, slope reduction requires the destruction of the original highway and the mountain inside, which seriously damages the original topography and greatly increases the amount of governance work. The use of retaining wall support requires the wall to be very thick and high, which is difficult to construct at the shoulder and will load the slope, and the stability of the slope cannot be guaranteed. Steel pipe piles are used as a single point support. For steep slopes of the shoulder, their stability may not be enough to support the entire steep shoulder, especially when the risk of slope sliding is high. In addition, considering the length of the steep shoulder, the use of steel pipe piles requires a high cost. At the same time, the construction of steel pipe piles on steep shoulders is difficult and the process is complicated, requiring additional support and safety measures.

[0004] Therefore, finding a combined retaining structure that can effectively prevent the steep slope of the shoulder from becoming unstable, and studying a construction method with simple construction technology, good stability and low economic cost are issues that need to be urgently addressed. Summary of the invention

[0005] One of the technical problems to be solved by the present invention is how to improve the stability of slopes such as shoulder steep slopes and better prevent landslides. The shoulder steep slope combined support structure and its construction method can better solve this problem, and the construction process is simple, the stability is good, and the economic cost is low.

[0006] In order to achieve the above-mentioned purpose, those skilled in the art have adopted the following technical scheme: a combined support structure for steep slopes of shoulders, comprising a lattice beam embedded and fixed on the surface of a mountain slope, and retaining walls connected to the lattice beam and respectively arranged at the top and the foot of the mountain slope, wherein the retaining wall at the top of the slope is an anchor retaining wall, the anchor pile foundation of the anchor retaining wall is connected to the top beam of the lattice beam, and the anchor rod of the anchor pile foundation is inserted downward into the rock mass, and the anchor retaining wall and the lattice beam are each fixedly connected to the rock mass by a plurality of anchor rods pulled obliquely downward; drainage holes are arranged in the anchor retaining wall, and the drainage holes are arranged obliquely downward toward the outer surface.

[0007] Furthermore, the anchor pile retaining wall is perpendicular to the road surface adjacent to it, the anchor pile retaining wall is close to the slope surface, and the corresponding hollowed-out part of the roadbed is filled with crushed stone and concrete; the top surface of the anchor pile retaining wall is provided with a concrete guardrail, and the concrete guardrail is extended and arranged along the road surface, wherein;

[0008] The top of the anchor pile retaining wall is reserved with steel bar ends to be welded, and the steel bar ends to be welded are welded together with the steel bars in the concrete guardrail.

[0009] Furthermore, the steel cage of the anchor pile retaining wall is welded and fixed to the corresponding anchor rods; the retaining wall and the concrete guardrail are each provided with a plurality of expansion joints along the direction of their paths.

[0010] Furthermore, the inclination angles of the anchor rods on the lattice beam and the anchor pile retaining wall to the horizontal line are both 15°.

[0011] Furthermore, the pipe hole of the drainage pipe serves as the drainage hole, and the upper side of the drainage pipe has a notch along the inclined direction, and a water-permeable cover covered with water holes is embedded in the notch. The two ends of the water-permeable cover have bent flanges, and the flanges are embedded in the end surfaces on both sides of the opening of the notch. There is a V-shaped plate structure between the two ends of the water-permeable cover.

[0012] Furthermore, a push plate is installed at the inner end of the drain pipe in a sliding manner along its axial direction, and the push plate can push out the construction slag debris accumulated in the drain pipe.

[0013] Furthermore, the push plate is connected via a connecting rod, and the connecting rod slides axially in the drain pipe to bring out the push plate.

[0014] At the same time, the present invention also proposes a construction method of a shoulder steep slope combined retaining structure, based on the implementation of the above structure, mainly including the following steps:

[0015] Step 1: level the steep slope to be constructed, excavate the foundation of the anchor pile retaining wall, and excavate to a stable soil layer to determine the elevation of the anchor pile foundation;

[0016] Step 2: construct the retaining wall at the foot of the slope. The retaining wall is buried 1.5m deep. The width and height are determined according to the calculation of the retaining wall at the foot of the slope. The wall is poured in layers to determine the top elevation of the retaining wall at the foot of the slope.

[0017] Step 3: According to the top elevation of the retaining wall at the foot of the slope and the elevation of the anchor pile foundation, determine the bottom and top positions of the lattice beam, and adjust them according to the current status of the slope;

[0018] Step 4: After the slope anchor construction is completed, the anchor pile foundation is poured. After hardening, the anchor pile holes are drilled. After the anchor pile holes are drilled, the back anchor rods of the anchor pile retaining wall are constructed. The anchor rods of the anchor piles and the back anchor rods are directly connected to the steel bars of the anchor pile retaining wall, and finally the concrete is poured. Among them, after the construction of all anchor rods of the anchor pile retaining wall is completed, the lattice beam formwork and the steel cage installation are carried out simultaneously.

[0019] Furthermore, when constructing the anchor pile retaining wall foundation, the length of the anchor pile foundation is adapted to the slope surface, all anchor piles are arranged in a plum blossom shape, with the same spacing between the left and right sides and the same spacing between the top and bottom, and each row of anchor piles is welded together with threaded steel bars;

[0020] The cross section of the lattice beam is square, the lattice beam is constructed by cast-in-place formwork, the internal steel bars are manufactured and installed on site, when pouring concrete, the distance between the discharge port or the bottom of the conduit and the bottom of the beam should not exceed 2.0m, and the anchor drilling machine is used to drill holes, and the hole diameter is not less than 110mm;

[0021] When drilling anchor holes, the drilling depth should exceed the designed length of the anchor rod by 0.5m. After drilling, the hole should be cleaned with water and the sediment at the bottom of the hole should be removed. After cleaning the hole, the drill rod should be pulled out quickly and then the anchor rod body should be placed.

[0022] When grouting the anchor rod, full-length grouting is adopted, and the grouting material is bonded with pure cement slurry. The grouting pipe should be placed in the hole at the same time as the anchor rod, and the grouting pipe should be 50~100mm away from the bottom of the hole.

[0023] Furthermore, when welding the anchor rod and the steel bar, one end of the anchor rod to be welded has been inserted into the drilled anchor hole, and the temporary installation position of the steel bar to be welded is adjusted so that the steel bar to be welded and the other end of the anchor rod to be welded can cross-contact each other, and then the anchor rod to be welded is pressed against the steel bar to be welded, keeping the two in relatively fixed contact, and then welding the contact part.

[0024] Compared with the prior art, the present invention mainly has the following beneficial effects: The steel bars of the anchor pile retaining wall of the present invention are connected to the anchor rods, which improves the lateral tensile capacity of the wall body and stabilizes the roadbed at the same time. The reinforced concrete guardrail is designed at the top of the wall, which functions as water interception and anti-collision. An organic whole is formed among the anchor pile anchor rods, cement slurry and the soil around the anchor pile, which improves the strength, bending resistance, tensile resistance and other properties of the anchor pile retaining wall. The bottom of the anchor pile retaining wall is connected to the lattice beam, and the lower part of the lattice beam is connected to the toe wall. A combined retaining structure is formed by the anchor pile retaining wall, lattice beam and toe wall, thereby improving the overall stability and anti-sliding ability of the structure, greatly improving the stability of the slope, and ensuring the safety and trafficability of the road.

[0025] The technical solution of the present invention has reliable technology, remarkable retaining effect on the roadbed and slope, high construction efficiency and low economic cost, making the invention more widely applicable, especially in the application of landslides on ridge roads, mountain slopes with highways at both the top and bottom of the slope, and roadbed slopes, etc., with remarkable application effects.

[0026] As for other positive effects, advantages and optimized technical features of the present invention, they will be illustrated and embodied through the detailed description of subsequent specific embodiments. Some technical features also require those of ordinary skill in the art to be better understood and applied through full research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the combined retaining structure of the shoulder steep slope of this road;

[0028] Figure 2 It is a cross-sectional schematic diagram of a kind of drain pipe;

[0029] Figure 3 It is a longitudinal sectional view of a kind of drain pipe;

[0030] Figure 4 It is a schematic diagram before the positioning fixture fixes the anchor rod and the steel bar in the construction method of the combined retaining structure of the shoulder steep slope of this road;

[0031] Figure 5 It is a schematic diagram after the positioning fixture fixes the anchor rod and the steel bar well.

[0032] Wherein, slope 1, road 2, concrete guardrail 3, anchor pile retaining wall 4, drain pipe 5, lattice beam 6, toe wall 7, steel bar anchor rod 8, catch basin 9, push plate 10, connecting rod 11, bushing 12, locking cover 13, positioning column 14, locking pin 15, sliding rod 16, driving column 17, mounting ring 18, rotating ring 19, strip-shaped sliding hole 20, turning handle 21, crank arm 22, elastic pressing arm 23, guiding hole 24, tension spring 25, steel bar to be welded 26, anchor rod to be welded 27. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the principle of the present invention will be explained in depth with reference to the accompanying drawings and at least one detailed embodiment. Those skilled in the art should be aware that the specific embodiments described below are only intended to explain the technical principles of the present invention, and are not intended to limit the present invention to be implemented in this way.

[0034] As a specific application example of the present invention, a road shoulder steep slope combined support structure is described in detail. Figure 1 As shown, it mainly includes an anchor pile retaining wall 4, a plurality of anchor rods, a lattice beam 6, and a slope foot retaining wall 7. Among them, the retaining wall at the top of the slope is an anchor pile retaining wall 4, that is, anchor piles are specially provided, and the anchor piles are provided with anchor rods, which need to be injected with cement slurry. These anchor rods in this embodiment can directly use steel anchor rods 8. Since the cars driving on the road 2 above the anchor pile retaining wall 4 belong to dynamic loads, plus the self-load of the retaining wall, the sliding force will become larger, so it is necessary to add a tensile force in the horizontal direction of the wall body, that is, several rows of anchor rods can be driven in the horizontal (or inclined) direction of the back of the anchor pile retaining wall 4, preferably inclined to effectively fix the retaining wall and protect the shoulder. In addition, there must be steel bars in the anchor pile retaining wall 4, the bottom of the steel bar is connected to the anchor rod of the anchor pile, and the back of the steel bar is connected to the horizontal anchor rod, and the three are connected together, and finally the formwork is supported and concrete is poured.

[0035] In this embodiment, the anchor pile retaining wall 4 is flush with the road surface of the corresponding road 2, steel bars are reserved on it, and a concrete guardrail 3 is designed. Since the road 2 is close to the edge of the steep slope of the shoulder, vehicles may lose control and rush under the slope 1. The crash barrier plays a role in protecting vehicles and intercepting water. In addition, the steel bars in the concrete guardrail 3 are connected to the anchor pile retaining wall 4, which is stronger than ordinary crash barriers.

[0036] As one of the specific implementation details, such as Figure 1 The lattice beam 6 is laid on the slope 1. The lattice beam 6 is also designed with anchor rods. The anchor rods can withstand tension and firmly fix the lattice beam 6 on the slope 1. The lattice beam 6 has a capping beam at the top and a foundation beam at the bottom. The capping beam is connected to the top anchor pile retaining wall 4, and the foundation beam is connected to the slope foot retaining wall 7 to form a whole to support the slope 1. Specifically, the anchor rod here can be HRB spiral steel bars, the grouting adopts full-length grouting, and the grouting material is pure cement slurry bonding, the cement grade is PC42.5R, ordinary Portland cement, and the water-cement ratio is 0.45~0.50.

[0037] The lattice beam 6 adopts a reinforced concrete structure. Before the construction of the beam, a groove should be formed according to the design requirements. If a groove is found on the slope, it must be filled with M5.0 cement mortar. If the pit is large, cement soil (the ratio of cement to soil is 1:4) can be used for backfilling. The lattice beam 6 must not be separated from the slope. The construction of the lattice beam 6 should be cast in place with formwork, and the formwork should be flat and clean.

[0038] The buried depth ratio of the retaining wall is less than 1.2m. The top reserved steel bar connects the foundation beam and the lattice beam 6 together. The retaining wall is set with settlement joints and expansion joints every 10m. The width of the joint is 20~30mm. The joint is filled with asphalt hemp, and the filling is not less than 150mm along the inner and outer top three sides. The retaining wall should be set with drainage holes, which can be directly realized by using drainage pipes 5, that is, the drainage holes are pre-buried with Φ75PVC pipes, the pipe mouth is inclined outward with a slope of 5%, the spacing of the drainage holes is 1.5×1.5m, and a 0.5×0.5×0.5m anti-filter bag should be set behind the hole. The base of the retaining wall should be hard plastic original soil, and the foundation burial depth should be determined according to the actual situation of on-site excavation. The bearing layer of the retaining wall is the residual layer or the fully weathered layer, and the bearing capacity of the foundation should be not less than 160kPa. The retaining wall should be poured and backfilled in layers, and the construction height of each layer should not exceed 2.0m.

[0039] More specifically, for the design of the drain pipe 5, Figure 2-3 , there may be a notch on the upper side of the drain pipe 5 along the inclined direction, that is, the extension path of the notch is in the inclined direction, and a water-permeable cover covered with water holes is embedded in the notch, so that water can penetrate into the drain pipe 5 to achieve drainage. The two ends of the water-permeable cover have bent flanges, which are embedded in the end faces on both sides of the opening of the notch for installation, and the two ends of the water-permeable cover are a V-shaped plate-like structure, and the tip of the V-shaped structure is directly facing the inner wall of the drain pipe 5, which has a concave water collection groove 9. On the inner side wall of the water-permeable cover above the water collection groove 9, a number of water-permeable holes are opened symmetrically on the left and right, and the water-permeable holes all extend obliquely downward toward the water collection groove 9, so that almost all the discharged water flows into the water collection groove 9 and is then discharged in a centralized manner.

[0040] Since the drain pipe 5 has a gap, in order to prevent the building materials from falling into the drain pipe 5 after the water-permeable cover is partially damaged, the drain pipe 5 can be opened as follows. Figure 3A push plate 10 is installed at the inner end of the drain pipe 5 in a sliding manner along the axial direction thereof. The push plate 10 is full of perforations for water permeability. The shape of the push plate 10 is consistent with the cross section of the tube hole of the drain pipe 5, so that the construction slag in the drain pipe 5 can be taken out when sliding in the drain pipe 5. In more detail, a connecting rod 11 can be fixed perpendicularly to the end surface of the push plate 10. The end of the connecting rod 11 close to the outer end of the drain pipe 5 is axially slidably installed on a sleeve 12. The sleeve 12 is fixed on the inner wall of the tube hole of the drain pipe 5. The end of the connecting rod 11 passing through the sleeve 12 is pressed by a locking cover 13 screwed on the sleeve 12, so that the push plate 10 and the connecting rod 11 are axially pressed and fixed in the drain pipe 5, so as to facilitate removal in subsequent use.

[0041] In addition, the above structural design is summarized as follows: Figure 3 One side of the sleeve 12 is fixed on the wall of the drain hole. One end of the sleeve 12 has a tapered thread. One end of the locking cover 13 has a tapered threaded hole that matches the thread of one end of the sleeve 12, and the other end has a center hole for the axial passage of the positioning column 14 at the end of the connecting rod 11. A locking pin 15 is also radially and elastically installed on the outer side wall of the locking cover 13. When the locking cover 13 is screwed on the sleeve 12 until the end face of the center hole contacts the end face of the connecting rod 11, so that the connecting rod 11 is axially fixed, the locking pin 15 can just axially bounce into a water hole on the water-permeable cover to fix the water-permeable cover, thereby preventing the water-permeable cover from sliding out downwards. When it needs to be taken out, the locking pin 15 is pulled down on the one hand, and the locking cover 13 is loosened on the other hand. Then, the connecting rod 11 can be taken out and the water-permeable cover is released at the same time. When necessary, the water-permeable cover can be taken out and replaced. Of course, this requires that a template be set at the notch of the drain pipe 5 during construction, and the water-permeable cover can be inserted after the template is removed later.

[0042] In order to carry out the actual construction of the above shoulder steep slope joint retaining structure, this implementation also proposes a construction method of the shoulder steep slope joint retaining structure, such as Figure 1In this application scenario, the slope 1 is surrounded by roads 2 above and below, and the slope 1 needs to be supported. During construction, the steep slope is leveled first, and the foundation of the anchor pile retaining wall 4 is excavated. The excavation is carried out to the stable soil layer, and over-excavation is avoided as much as possible. The elevation of the anchor pile foundation is determined. Then the retaining wall 7 at the foot of the slope is constructed. The retaining wall is buried at a depth of 1.5m. The width and height are determined according to the verification of the retaining wall, and the top elevation is determined by layered pouring. According to the top elevation of the retaining wall and the elevation of the anchor pile foundation, the bottom and top of the lattice beam 6 are determined, and adjusted according to the current status of the slope. After the slope anchor rod construction is completed, the anchor pile foundation is poured, and the anchor piles of the anchor pile foundation are drilled after hardening. After the anchor pile drilling is completed, the anchor rod of the anchor pile retaining wall 4 is constructed. The anchor rod of the anchor pile and the wall back anchor rod of the anchor pile retaining wall 4 are directly connected to the wall body steel bars, and finally the concrete is poured. After the anchor rod construction of the anchor pile retaining wall 4 is completed, the formwork of the lattice beam 6 and the installation of the steel cage can be carried out simultaneously to improve efficiency.

[0043] In this embodiment, the anchor pile retaining wall 4 has a base width of 1m and a length determined according to the slope. The anchor piles are arranged in a plum blossom shape, with a left-right spacing of 2m and a top-bottom spacing of 0.5m. Each row of anchor piles is welded together with 18cm threaded steel bars. Two anchor rods are placed under each anchor pile. The steel bars are threaded steel bars with a diameter of 25cm. The anchor rods are welded together with the steel cage of the retaining wall. The steel cage is made of 16cm threaded steel bars with a spacing of 0.5m. The horizontal main bars of the retaining wall are also made of 16cm threaded steel bars with a spacing of 0.5m. The main bars are welded together with the anchor rods at the back, and all welding is full welding. The anchor pile retaining wall 4 is perpendicular to the road surface and close to the slope surface. The hollowed-out part of the roadbed is backfilled with gravel and concrete. Steel bars are reserved at the top of the anchor pile retaining wall 4 and welded together with the steel bars of the concrete guardrail 3. The concrete guardrail 3 is 0.9m high, 0.2m wide at the top, and 0.4m wide at the bottom. An expansion joint is designed every 10m between the retaining wall and the concrete guardrail 3.

[0044] In this embodiment, if the drainage holes of the anchor pile retaining wall 4 are directly pre-buried with PVC pipes, Φ75 PVC pipes can be used, and the pipe mouth is inclined outward at a slope of 5%. The drainage holes are spaced 2m up and down and 3m left and right. A 0.5×0.5×0.5m filter bag is set behind the hole. The retaining wall is cast and backfilled in layers, and the construction height of each layer is not more than 2.0m.

[0045] In this embodiment, the cross section of the lattice beam 6 is square, with a specification of 0.3m×0.3m. The lattice beam 6 should be constructed by cast-in-place formwork, and the formwork should be flat and clean to meet the requirements of strength and rigidity. The steel bars can be made and installed on site, but the number and configuration of the steel bars are determined according to the design. When pouring concrete, the distance between the discharge port or the bottom of the conduit and the bottom of the beam should not exceed 2.0m to prevent the concrete from segregating when it falls. The anchor drill is used to make holes, and the hole diameter is not less than 110mm.

[0046] During anchor construction, the drilling angle of the anchor hole is allowed to deviate by ±2°, the hole position is allowed to deviate by ±1%, and the hole depth and rod length are allowed to deviate by ±50mm. Before the rod body is lowered, anti-corrosion treatment should be carried out, and the anchor rod body should be straight, rust-free and degreased before use. The drilling depth should exceed the designed length of the anchor rod by 0.5m. After drilling, the hole should be cleaned with water and the sediment at the bottom of the hole should be removed. After cleaning the hole, the drill rod should be quickly pulled out and the anchor rod body should be placed.

[0047] Specifically, the anchor grouting adopts full-length grouting, and the grouting material is pure cement slurry bonding, cement grade PC42.5R, ordinary Portland cement, and cement mortar uses pure cement slurry with a water-cement ratio of 0.45~0.50. The 28-day unconfined compressive strength of the slurry material is not less than 30MPa. The grouting pressure is 0.5~1.0MPa, and the grouting pipe should be placed in the hole at the same time as the anchor, and the grouting pipe should be about 50~100mm from the bottom of the hole. The bottom of the lattice beam 6 is connected to the retaining wall 7 at the foot of the slope, and the foundation beam acts on the strongest part of the frame to ensure the best support effect.

[0048] In this embodiment, if the height of the retaining wall 7 at the foot of the slope is less than 5m, no steel bars are required, and the retaining wall should be provided with drainage holes, which are pre-buried with Φ75 PVC pipes, with the pipe openings inclined outwards at a slope of 5%, and the spacing between the drainage holes is 1.5×1.5m, and a 0.5×0.5×0.5m anti-filter bag should be set behind the holes. In addition, during construction, the base of the retaining wall here should be hard plastic original soil, the foundation burial depth is determined according to the actual on-site excavation situation, the retaining wall bearing layer is the residual layer or the fully weathered layer, and the foundation bearing capacity is not less than 160kPa.

[0049] In addition, it should be noted that in the above construction, the number of anchor rods for acceptance testing is not less than 5% of the total number, and not less than 3. The lattice beam 6 has reserved acceptance inspection anchor rods, and the anchor pile retaining wall 4 anchor rods use PVC pipe sleeves to reserve inspection anchor rods. The anchor piles are directly extended to the top. After the subsequent inspection is completed, the excess steel bars are cut off and the hole is sealed with cement.

[0050] Finally, since the number of anchor rods and various steel bars fixed or welded during the entire construction operation is very large, and it is a particularly critical process, special attention needs to be paid to avoid extremely dangerous situations such as cold welding. Therefore, it is necessary to firmly and accurately contact and bring the corresponding anchor rod 27 to be welded into contact with the steel bar 26 to be welded, and then weld to ensure the welding quality. In this embodiment, when welding the anchor rod and the steel bar, one end of the anchor rod 27 to be welded has been inserted into the drilled anchor hole. At this time, it is necessary to adaptively adjust the temporary installation position of the steel bar 26 to be welded according to the on-site conditions so that the steel bar 26 to be welded and the other end of the anchor rod 27 to be welded can cross-contact. For example, the anchor rod at this time is placed on the upper surface of the steel bar, and then the anchor rod 27 to be welded is pressed against the steel bar 26 to be welded, so as to keep the two relatively fixed in contact. Then, the welder welds the contact part and then fixes them together. Specifically, in practice, a positioning fixture can be used to achieve pre-positioning installation of the steel bar and the anchor rod to facilitate fast and reliable construction, such as Figure 4-5 As shown, the positioning fixture includes a plurality of sliding rods 16 arranged in a circular array on the surface of a mounting ring 18. The sliding rods 16 can be made of rectangular steel bars. A driving column 17 is fixed to the surface of each sliding rod 16. The driving column 17 here can be a cylinder. Each driving column 17 slides into a strip-shaped sliding hole 20 on a rotating ring 19 in a sliding fit. The strip-shaped sliding hole 20 can be an arc-shaped waist hole structure or a straight hole extending along an inclined path. The rotating ring 19 is coaxially rotatably mounted on the end face of the mounting ring 18. A turning handle 21 is fixed to one side of the rotating ring 19 for hand holding. A curved arm 22 is fixed to the other side of the rotating ring 19. The curved arm 22 is similar to a hook-shaped structure. The free end of the curved arm 22 is slidably located in a guide hole 24 of an elastic pressure arm 23. The guide hole 24 can be a rectangular strip hole. A tension spring 25 connecting the curved arm 22 and the elastic pressure arm 23 is also provided in the angle region between the curved arm 22 and the elastic pressure arm 23, so as to limit the elastic pressure arm 23 and the curved arm 22 to a set angle range under normal conditions.

[0051] In actual operation, the anchor rod and the steel bar are first pre-positioned and contacted for further reinforcement and installation, that is, the overall axial sleeve formed by the installation ring 18 and the rotating ring 19 is placed on the steel bar to be welded. At this time, the annular passable area surrounded by all the sliding rods 16 is larger, so that the positioning fixture as a whole can be easily placed on the steel bar 26 to be welded, and then the elastic pressure arm 23 is pulled away from the curved arm 22, so that the elastic pressure arm 23 can be pre-pressed on the steel bar to maintain the initial contact state between the anchor rod and the steel bar. At this time, due to the tension of the tension spring 25, the elastic pressure arm 23 further presses the anchor rod to a position of extrusion contact with the surface of the steel bar, achieving a more secure pre-contact positioning, and then, the turning handle 21 is turned, and the rotating ring 19 is rotated, so that all the sliding rods 16 are synchronously moved axially and approached to the steel bar under the sliding cooperation of the driving column 17 and the strip slider, that is, they are all synchronously moved toward the steel bar along the radial direction of the rotating ring 19, and as shown Figure 5 As shown, the steel bar is finally clamped circumferentially. In the above-mentioned short process of clamping the steel bar, when the curved arm 22 rotates with the turning handle 21, it rotates and squeezes the elastic pressure arm 23 in the guide hole 24, so that the elastic pressure arm 23 presses the anchor rod tightly on the surface of the steel bar that has been clamped and fixed at this moment, which is equivalent to the steel bar being clamped circumferentially while the anchor rod is squeezed toward the steel bar, so that the anchor rod and the steel bar are in real sense firmly contacted together, avoiding the accidental loosening of the two due to loose contact during welding, which affects the reliability of welding. In addition, it should be specially noted that for occasions where there is no high requirement for the inclination of the anchor rod installation, the steel bar can be directly clamped with the bar slider, and the elastic pressure arm can be used to press the anchor rod, without the need for prior contact at the initial moment of welding. In many cases, not all anchor rods must have a precise installation angle, but only need to be able to pull the anchor pile retaining wall to combine with the rock mass to transmit force, for example, it can be pulled obliquely or horizontally, so there is no special requirement. In this case, the installation positioning before welding is faster. In actual construction, the rotating disk can also be driven electrically. Technical personnel in the field can adaptively design, manufacture and use this structure, which will be more convenient to use in general occasions.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. A series of detailed descriptions of the embodiments of the present application, as for the specific examples used in the present application, have been described in detail on the technical principles and implementation methods of the present application. They are only used to help those skilled in the art to have an in-depth and comprehensive understanding of the design concept of the present application, and should not be understood as a sole or selective limitation on the technical principles of the present application. As for the detailed description of the present invention by the preferred embodiments mentioned in the present application, a person of ordinary skill in the art should be able to make simple modifications to the technical solutions of the present invention or replace them with equivalent means on the basis of these preferred embodiments, but the core technical principles should be covered in the scope of protection embodied in the claims of the present invention without departing from the technical ideas, design purposes and scope of application of the present invention.

Claims

1. A road shoulder steep slope joint retaining structure, comprising a lattice beam (6) embedded and fixed on the surface of a mountain slope (1), and retaining walls connected to the lattice beam (6) and respectively arranged at the top and the foot of the mountain slope (1), characterized in that: The retaining wall located at the top of the slope is an anchor pile retaining wall (4), the anchor pile foundation of the anchor pile retaining wall (4) is connected to the top beam of the lattice beam (6), and the anchor pile foundation, the anchor pile retaining wall (4) and the lattice beam (6) are each fixedly connected to the rock mass through a plurality of anchor rods; a drainage hole is provided in the anchor pile retaining wall (4), and the drainage hole is arranged obliquely downward toward the outer surface; The pipe hole of the drainage pipe (5) serves as the drainage hole. The upper side of the drainage pipe (5) has a notch along the inclined direction. A water-permeable cover covered with water holes is embedded in the notch. The two ends of the water-permeable cover have bent flanges, and the flanges are embedded in the end surfaces on both sides of the opening of the notch. A V-shaped plate structure is formed between the two ends of the water-permeable cover. The inner wall of the drainage pipe (5) facing the tip of the V-shaped structure has a concave water collection groove (9). On the inner side wall of the water-permeable cover above the water collection groove (9), a plurality of water-permeable holes are symmetrically opened on the left and right sides, and the water-permeable holes all extend obliquely downward toward the water collection groove (9). A push plate (10) is installed at the inner end of the drain pipe (5) in a sliding manner along the axial direction thereof, and the push plate (10) can push out the construction slag debris accumulated in the drain pipe (5); The push plate (10) is covered with perforations, and the shape of the push plate (10) is consistent with the cross-section of the tube hole of the drain pipe (5). The push plate (10) is connected by a connecting rod (11), and the connecting rod (11) slides axially in the drain pipe (5) to bring out the push plate (10); the connecting rod (11) is fixed perpendicularly to the end surface of the push plate (10), and the end of the connecting rod (11) close to the outer end of the drain pipe (5) is axially slidably installed on a sleeve (12), and the sleeve (12) is fixed on the inner wall of the tube hole of the drain pipe (5), and the end of the connecting rod (11) passing through the sleeve (12) is pressed by a locking cover (13) screwed on the sleeve (12), so that the push plate (10) and the connecting rod (11) are axially tightened and fixed to the drain pipe. (5); one side of the shaft sleeve (12) is fixed on the hole wall of the drain hole, and one end of the shaft sleeve (12) has a conical thread; one end of the locking cover (13) has a conical thread hole that is threadedly matched with one end of the shaft sleeve (12), and the other end has a center hole for the axial passage of the positioning column (14) at the end of the connecting rod (11); a locking pin (15) is also radially elastically and telescopically installed on the outer wall of the locking cover (13), when the locking cover (13) is threadedly matched on the shaft sleeve (12) until the end face of the center hole contacts the end face of the connecting rod (11) to axially fix the connecting rod (11), the locking pin (15) just axially pops into a water hole on the water-permeable cover to prevent the water-permeable cover from sliding downward.

2. A road shoulder steep slope combined retaining structure according to claim 1, characterized in that: The anchor pile retaining wall (4) is perpendicular to the road surface adjacent to it, and the anchor pile retaining wall (4) is close to the slope surface, and the hollowed-out part of the roadbed corresponding to it is filled with crushed stone and concrete; the top surface of the anchor pile retaining wall (4) is provided with a concrete guardrail (3), and the concrete guardrail (3) is extended and arranged along the road surface, wherein; The top of the anchor pile retaining wall (4) is reserved with steel bar ends to be welded, and the steel bar ends to be welded are welded together with the steel bars in the concrete guardrail.

3. A road shoulder steep slope combined retaining structure according to claim 1, characterized in that: The steel cage of the anchor pile retaining wall (4) is welded and fixed to the corresponding anchor rods; the retaining wall and the concrete guardrail (3) are each provided with a plurality of expansion joints along their path directions.

4. A road shoulder steep slope combined retaining structure according to claim 1, characterized in that: The inclination angles of the anchor rods on the lattice beam (6) and the anchor pile retaining wall (4) to the horizontal line are both 15°.

5. A construction method of a road shoulder steep slope combined retaining structure according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: level the steep slope to be constructed, and excavate the foundation of the anchor pile retaining wall (4). During the excavation, it is necessary to excavate to a stable soil layer and determine the elevation of the anchor pile foundation; Step 2, constructing the retaining wall (7) at the foot of the slope, determining the width and height according to the calculation of the retaining wall (7) at the foot of the slope, pouring the retaining wall (7) in layers, and determining the top elevation of the retaining wall (7) at the foot of the slope; Step 3: According to the top elevation of the retaining wall (7) at the foot of the slope and the elevation of the anchor pile foundation, determine the bottom and top positions of the lattice beam (6), and adjust them according to the current status of the slope; Step 4: After the anchor rod construction of the slope is completed, the anchor pile foundation is poured, and after hardening, the anchor pile holes are drilled. After the anchor pile holes are drilled, the back anchor rods of the anchor pile retaining wall (4) are constructed. The anchor rods of the anchor piles and the back anchor rods are directly connected to the wall reinforcement of the anchor pile retaining wall (4), and finally concrete is poured; wherein, after the construction of all the anchor rods of the anchor pile retaining wall (4) is completed, the lattice beam (6) formwork and the steel cage installation are carried out simultaneously; When welding the anchor rod and the steel bar, one end of the anchor rod (27) to be welded has been inserted into the drilled anchor hole, and the temporary installation position of the steel bar (26) to be welded is adjusted so that the steel bar (26) to be welded and the other end of the anchor rod (27) to be welded can cross contact, and then the anchor rod (27) to be welded is pressed against the steel bar (26) to be welded, and the two are kept in relatively fixed contact, and then the contact part is welded; A positioning fixture is used to realize the pre-positioning installation of the steel bar and the anchor rod, the positioning fixture comprises a plurality of sliding rods (16) arranged in a circular array on the surface of a mounting ring (18), a driving column (17) is fixed on the surface of each sliding rod (16), the driving column (17) is slidingly fitted into a strip-shaped sliding hole (20) on a rotating ring (19), the rotating ring (19) is coaxially rotatably mounted on the end surface of the mounting ring (18), a turning handle (21) is fixed on one side of the rotating ring (19), and a curved arm (22) is fixed on the other side, the free end of the curved arm (22) is slidingly fitted in a guide hole (24) of an elastic pressure arm (23), and a tension spring (25) connecting the curved arm (22) and the elastic pressure arm (23) is provided in the angle region between the curved arm (22) and the elastic pressure arm (23); When the anchor rod and the steel bar are pre-positioned and installed, the installation ring (18) and the rotating ring (19) are first put on the steel bar as a whole, and then the elastic pressure arm (23) is pulled away from the curved arm (22) so that the elastic pressure arm (23) can be pre-pressed on the steel bar. At this time, due to the tension of the tension spring (25), the elastic pressure arm (23) pre-presses the anchor rod to a position in contact with the surface of the steel bar, and then the turning handle (21) is rotated to make all the sliding rods (16) move axially synchronously and approach the steel bar, and finally clamp the steel bar in an annular direction. At the same time, when the curved arm (22) rotates with the turning handle (21), it rotates in the guide hole (24) and squeezes the elastic pressure arm (23), so that the elastic pressure arm (23) presses the anchor rod tightly on the surface of the steel bar that has been clamped and fixed at this moment.

6. The construction method of the shoulder steep slope combined retaining structure according to claim 5 is characterized in that: When constructing the foundation of the anchor pile retaining wall (4), the length of the anchor pile foundation is adapted to the slope surface, all the anchor piles are arranged in a plum blossom shape, the left and right spacings are consistent, and the upper and lower spacings are consistent, and each row of anchor piles is welded together with threaded steel bars; The cross section of the lattice beam (6) is square. The lattice beam (6) is constructed by cast-in-place support. The internal steel bars are manufactured and installed on site. When pouring concrete, the distance between the discharge port or the bottom of the conduit and the bottom of the beam should not exceed 2.0 m. The anchor drilling machine is used to drill holes, and the hole diameter is not less than 110 mm. When drilling anchor holes, the drilling depth should exceed the designed length of the anchor rod by 0.5m. After drilling, the hole should be cleaned with water and the sediment at the bottom of the hole should be removed. After cleaning the hole, the drill rod should be pulled out quickly and then the anchor rod body should be placed. When grouting the anchor rod, full-length grouting is adopted, and the grouting material is bonded with pure cement slurry. The grouting pipe should be placed in the hole at the same time as the anchor rod, and the grouting pipe should be 50~100mm away from the bottom of the hole.

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