Rock inclined anchor rod foundation of overhead transmission line

Abstract

The utility model discloses an overhead transmission line rock inclined anchor rod foundation which comprises a vertically-arranged foundation body, the upper end of the foundation body is higher than the natural ground, an anchor disc is arranged in the foundation body, a foundation bolt extending upwards is arranged on the anchor disc, and the upper end of the foundation bolt is higher than the upper end of the foundation body. The upper ends of the anchor piles are located in the foundation body, and the lower ends of the anchor piles are obliquely arranged in a mode of gradually expanding outwards relative to the upper ends of the anchor piles; anchor bars are arranged in the anchor piles, the upper ends of the anchor bars are exposed out of the upper ends of the anchor piles, and the upper ends of the anchor bars are connected with the anchor disc. According to the scheme, the problem that an existing anchor rod foundation is various in form limiting condition is solved, the application range of the rock anchor rod foundation is widened, and the mechanical construction rate of a mountainous area can be greatly increased.

Description

TECHNICAL FIELD

[0001] The utility model belongs to overhead transmission line foundation technical field, concretely relates to a kind of overhead transmission line rock inclined anchor rod foundation. BACKGROUND

[0002] Rock anchor foundation is a kind of "resource saving, environment friendly" foundation type in mountainous area of China, which can fully utilize the uplift bearing capacity of rock foundation, has high degree of mechanization in construction, small size of construction equipment and small damage to environment. In recent years, it is favored in the selection of overhead transmission line. The existing anchor rod foundation construction method mainly adopts straight anchor type and pile cap type foundation. The current power industry standard "Overhead Transmission Line Anchor Rod Foundation Design Specification" DL / T 5544-2018 stipulates that the anchor hole spacing should not be less than 3.0-4.0 times the anchor hole diameter, and should not be less than 2.5 times the anchor hole diameter, and the clear distance should not be less than 160 mm. Considering that the straight anchor type anchor rod foundation uses anchor bolts as anchor bars and is anchored in good rock stratum, the anchor spacing is limited by the anchor bolt spacing, the tower foot plate needs to be modified to meet the minimum spacing requirement of anchor bars, and it is only suitable for tower sites with small foundation force, thin overburden, good lower rock and gentle slope. The pile cap type anchor rod foundation has problems such as large excavation of pile cap in steep mountainous area, thickness limitation of overburden, complex construction process and poor stability of foundation pit backfill. Due to the above two types of anchor rod foundation, the application rate of rock anchor foundation in mountainous area of overhead transmission line engineering is low, which hinders the popularization of rock anchor foundation construction in transmission line industry. CONTENT OF UTILITY MODEL

[0003] The utility model solves the technical problems in the prior art that the existing anchor rod foundation form has many restrictions, which makes it difficult to set anchor rod foundation in mountainous area, and realizes that the anchor rod foundation is no longer restricted by the minimum spacing of anchor pile specified in the anchor rod specification and is no longer limited by the influence of thick overburden, greatly improving the application range of rock anchor foundation.

[0004] According to the technical scheme of the utility model, the utility model provides a kind of overhead transmission line rock inclined anchor rod foundation, including the foundation main body of vertical setting, the upper end of foundation main body is higher than natural ground, anchor disc is set in foundation main body, anchor disc is provided with the anchor bolt that extends upwards, the upper end of anchor bolt is higher than the upper end of foundation main body;It also includes a plurality of anchor piles, the upper end of anchor pile is located in foundation main body, the lower end of anchor pile is gradually outwardly expanded and inclinedly arranged relative to the upper end of anchor pile;Anchor rod is arranged in anchor pile, the upper end of anchor rod is exposed to the upper end of anchor pile, and the upper end of anchor rod is connected with anchor disc.

[0005] Further, the upper part of the foundation body is a foundation column section, a lower end of the foundation column section is connected with a foundation bottom expansion section, a cross-sectional dimension of the lower end of the foundation bottom expansion section is greater than that of the upper end of the foundation bottom expansion section and that of the foundation column section; the anchor disc is located in the foundation column section, and the upper end of the anchor pile is located in the foundation bottom expansion section.

[0006] Further, the foundation bottom expansion section is located below the rock section below the natural ground.

[0007] Further, the foundation column section is in a cylindrical shape, the foundation bottom expansion section is in a circular truncated cone shape, the central axis of the foundation column section and that of the foundation bottom expansion section coincide, and the cross-sectional dimension of the foundation column section is consistent with that of the upper end of the foundation bottom expansion section.

[0008] Further, the anchor disc is distributed with a plurality of vertical through anchor bolt holes, a plurality of anchor bolts pass through the anchor bolt holes one by one in a one-to-one correspondence; the lower end of the anchor bolt is threadedly connected with a nut, and the nut is located below the anchor disc.

[0009] Further, the anchor pile has an inclination angle of 10°-25° with respect to the vertical direction.

[0010] Further, the anchor pile is a plurality of circumferentially uniform distribution.

[0011] Further, the inclination angle of the anchor bar is the same as that of the anchor pile where the anchor bar is located.

[0012] Further, the spacing between the upper ends of adjacent anchor piles is less than 2.5 times the diameter of the anchor pile.

[0013] Further, the upper end of the anchor bolt is connected with a tower foot plate of the overhead transmission line.

[0014] Compared with the prior art, the beneficial technical effects of the utility model are as follows:

[0015] 1、 the utility model discloses an overhead transmission line rock inclined anchor rod foundation adopts an inclined anchor rod scheme, and the inclined anchor pile increases the anchor pile spacing, so that the foundation is no longer restricted by the minimum spacing of the anchor rod specification for the anchor pile, the diameter of the undisturbed soil foundation pit only needs to satisfy the construction operation space, under the same column diameter, the number of anchor piles can be greatly increased, thereby the maximum bearing capacity upper limit of the foundation is improved, the application range of the rock anchor rod foundation is expanded, and the mechanical construction rate in mountainous areas is greatly improved.

[0016] 2, the anchor rod foundation of overhead transmission line rock inclined of the utility model is fixed directly with anchor disc by welding, anchor disc and anchor bolt are fastened by nut, which can make the foundation force directly pass to anchor pile through anchor bolt, and the force transmission is more direct; at the same time, since anchor bolt and anchor disc are fastened by nut, the minimum requirement of anchor bolt anchoring length is no longer limited, which can effectively reduce the amount of anchor bolt, effectively reduce anchor bolt anchoring length, and save anchor bolt weight.

[0017] 3, the anchor rod foundation of overhead transmission line rock inclined of the utility model adopts original column body foundation pit hole forming, no longer uses traditional large excavation pile cap type anchor rod foundation, which greatly reduces excavation earthwork quantity, makes the foundation construction more environmentally friendly; since it is original soil foundation pit excavation, it is no longer limited by the influence of thicker cover layer, and the anchor rod foundation of the utility model can still be used when the cover layer thickness is greater than 3 meters; in the area where the soil cover layer is thick, it is easier to meet the requirement of 0.5m minimum depth embedded in rock in the specification, and only the column needs to be deepened; it meets the composite anchor rod calculation theory, the original soil column part can consider its beneficial effect according to the excavation foundation; the amount of foundation concrete, foundation pit excavation quantity and surplus soil transportation quantity are reduced, and the goal of "resource-saving and environment-friendly" is realized. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is the structure schematic view of the anchor rod foundation of overhead transmission line rock inclined provided by the utility model.

[0019] Figure 2 is Figure 1 the local enlarged view of anchor disc, anchor bolt and nut part.

[0020] Figure 3 is Figure 1 the top view schematic view.

[0021] Figure 4 is the three-dimensional structure schematic view of the anchor rod foundation of overhead transmission line rock inclined provided by the utility model.

[0022] Figure 5 is the structure schematic view of the anchor rod foundation of overhead transmission line rock inclined of another embodiment of the utility model.

[0023] Explanation of reference signs in the drawings:

[0024] 1, natural ground surface; 2, rock section; 3, foundation column section; 4, foundation bottom expanding section; 5, anchor pile; 6, anchor bolt; 7, anchor disc; 8, anchor bar; 9, nut. DETAILED DESCRIPTION

[0025] The utility model provides a kind of overhead transmission line rock inclined anchor rod foundation, especially applicable to mountainous area, solve the many form restrictions of existing anchor rod foundation, further difficult to set anchor rod foundation in mountainous area and other problems, the utility model can effectively increase anchor pile number using annular inclined anchor rod arrangement, anchor pile is set to 10 °~25 ° out-of-plane angle, by increasing anchor pile embedment, anchor pile spacing gradually enlarges with depth, when satisfying minimum anchor pile spacing, it is anchor pile calculation embedment starting point;Anchor bar is implanted after anchor pile, and the part exposed to foundation pit bottom still extends into foundation interior according to corresponding angle, is welded in the periphery of foundation center anchoring disc, fastening anchor disc in the middle is reserved anchor bolt hole, anchor bolt is fastened with anchor disc using nut, anchor bolt is reserved certain exposed length and is connected with upper tower foot plate;So as to realize no longer be subject to the constraint of anchor rod specification to anchor pile minimum spacing, no longer be limited by the influence of relatively large overburden thickness, greatly improve the application range of rock anchor rod foundation.

[0026] Rock anchor rod foundation is to take rock mass as the main anchoring bearing stratum, and anchor rod as the main tensile component. Mountainous area transmission line rock anchor rod foundation mainly adopts straight anchor type and pile cap type foundation. Straight anchor type anchor rod foundation uses anchor bolt as anchor bar and anchors into better rock layer, and the anchoring spacing is limited by anchor bolt spacing, which needs to be modified to increase the tower foot plate to meet the minimum spacing requirement of anchor bar, and is only applicable to tower sites with small force, thin overburden, good lower rock and gentle slope. The pile cap type anchor rod foundation has problems of large excavation of pile cap in steep mountainous area, overburden thickness limitation, complex construction process and poor stability of foundation pit backfill. Another type of original soil composite anchor rod foundation also has problems of anchor bar number and anchor bar anchoring length being limited by pile diameter, which is difficult to be used in practical application. How to improve the application range of mountainous area rock anchor rod foundation has been a problem for the transmission line industry.

[0027] Please refer to Figures 1 to 5 The utility model discloses a kind of overhead transmission line rock inclined anchor rod foundation, including vertically arranged foundation main body, the upper end of foundation main body is higher than natural ground 1, the lower end of foundation main body is located underground, rock mass is set in foundation main body There is anchor disc 7, anchor disc 7 is provided with upwardly extending anchor bolt 6, the upper end of anchor bolt 6 is higher than the upper end of foundation main body;It also includes a plurality of anchor piles 5, the upper end of anchor pile 5 is located in foundation main body, the lower end of anchor pile 5 is gradually outwardly expanded relative to the upper end of anchor pile 5 and is inclinedly arranged, the lower end of anchor pile 5 is located outside foundation main body and is located in rock mass;Anchor bar 8 is arranged in anchor pile 5, the upper end of anchor bar 8 is exposed to the upper end of anchor pile 5, and the upper end of anchor bar 8 is connected with anchor disc 7.

[0028] The utility model includes bottom expansion ( Figure 1 As shown) and not bottom expansion ( Figure 5In both cases shown, the purpose of the expanded footing is mainly to reduce the amount of concrete used (equivalent to reducing the volume of the upper part of the main body of the foundation), and if there is soil or other reasons, it can not be implemented. The following is an example of the embodiment shown to explain more specifically. Figure 1 The embodiment shown is taken as an example to explain more specifically.

[0029] Please refer to Figures 1 to 4 , the upper part of the foundation body is the foundation column section 3, the upper end of the foundation column section 3 is higher than the natural ground 1, the lower end of the foundation column section 3 is connected with the foundation expansion section 4, the cross-sectional size of the lower end of the foundation expansion section 4 is greater than that of the upper end of the foundation expansion section 4 and greater than that of the foundation column section 3. The foundation column section 3 and the foundation expansion section 4 are formed by pouring concrete, and constitute an integrated concrete foundation. More specifically, for example, the foundation column section 3 is cylindrical, the foundation expansion section 4 is circular truncated cone, the central axis of the foundation column section 3 and the foundation expansion section 4 coincide, and the cross-sectional size of the foundation column section 3 is consistent with that of the upper end of the foundation expansion section 4.

[0030] An anchor plate 7 (or anchor plate) is arranged in the foundation column section 3, for example, at the upper and central position inside the foundation column section 3. The anchor plate 7 is provided with upwardly extending anchor bolts 6, and the upper end of the anchor bolt 6 is higher than the upper end of the foundation column section 3. More specifically, please refer to Figure 2 、 Figure 3 , the anchor plate 7 is distributed with a plurality of vertical through anchor bolt holes, a plurality of anchor bolts 6 pass through the anchor bolt holes one by one, the lower end of the anchor bolt 6 is threadedly connected with a nut 9, and the nut 9 is located below the anchor plate 7, so as to fasten the anchor bolt 6 through the nut 9. The anchor bolt 6 is circumferentially uniformly distributed, and the number is determined according to the actual engineering, and in the illustrated embodiment, the anchor bolt 6 is circumferentially uniformly distributed four. For the application scenario of the embodiment, the upper end of the anchor bolt 6 is reserved with a certain exposed length to be connected with the tower foot plate of the overhead transmission line.

[0031] It also includes a plurality of anchor piles 5 (or anchor rods), the upper end of the anchor pile 5 is located in the foundation expansion section 4, and the lower end of the anchor pile 5 is arranged in a tilt relative to the upper end of the anchor pile 5. The anchor pile 5 is provided with an anchor bar 8, the upper end of the anchor bar 8 is exposed from the upper end of the anchor pile 5, and the upper end of the anchor bar 8 is connected with the anchor plate 7, preferably directly welded and fixed. More specifically, the inclination angle of the anchor pile 5 relative to the vertical direction is, for example, 10°-25°. The inclination angle of the anchor bar 8 is the same as that of the anchor pile 5 where it is located. The anchor pile 5 is circumferentially uniformly distributed, for example, circumferentially uniformly distributed eight, and the number is determined according to the actual engineering.

[0032] The distance between the upper ends of the adjacent anchor piles 5 (the distance D1 between the starting points of the column bottom anchor piles) is less than 2.5 times the diameter D of the anchor piles 5, the distance between the anchor piles is gradually enlarged with the depth by increasing the anchor pile embedding depth, the starting point of the anchor pile calculation embedding depth is when the minimum anchor pile distance is met, the position of the starting point of the anchor pile calculation embedding depth corresponds to the distance D2 meeting the minimum distance in the specification, and is generally located at the middle upper segment of the anchor piles 5, and the specific position is determined according to calculation, and the length of the anchor piles 5 above the starting point of the anchor pile calculation embedding depth can be referred to as the anchor pile deepening height. The anchor bars are exposed from the bottom of the foundation pit after being implanted into the anchor piles, and still extend into the foundation at a corresponding angle.

[0033] Please refer to Figure 1 The utility model is especially suitable for mountainous areas, and the rock section 2 is below a certain depth of the natural ground 1, and the natural ground 1 and the rock section 2 are both inclined relative to the horizontal plane, of course, the actual section is usually not a straight line, and the mountain slope condition is only schematically shown in the figure. The foundation bottom expanding section 4 is wholly or partially (mostly) below the rock section 2 below the natural ground 1, so that the foundation bottom expanding section 4 can better play a fixing role. Figure 1 In the embodiment, only a small part of the upper right corner of the foundation bottom expanding section 4 is above the rock section 2 relative to the whole. The rock section 2 below is a rock foundation, that is, a weathered rock mass below the foundation bearing external load, and the weathering degree is generally strong weathering, medium weathering, slight weathering and the like. The rock-embedded depth of the foundation bottom expanding section 4 below the rock section 2 needs to meet the requirements. For example Figure 1 In the embodiment, the distance between the intersection position between the foundation bottom expanding section 4 and the rock section 2 and the bottom surface of the foundation bottom expanding section 4 is the rock-embedded depth, and the depth of the foundation bottom expanding section 4 needs to ensure sufficient rock-embedded depth.

[0034] In order to further highlight the beneficial technical effects of the utility model and facilitate the understanding of the technical scheme, a recommended construction process is given below, which comprises the following steps:

[0035] 1. Excavate the undisturbed soil foundation pit corresponding to the foundation column section 3;

[0036] 2. Drill the anchor pile hole corresponding to the anchor pile 5 by using the anchor rod drilling machine at a predetermined inclination angle;

[0037] 3. Place the anchor bar 8 in the anchor pile hole and then pour the anchoring agent;

[0038] 4. Excavate the foundation pit corresponding to the foundation bottom expanding section 4 after the anchor pile 5 is cured;

[0039] 5. Position the anchor disc 7 and overlap and weld the anchor bar 8 around the anchor disc 7;

[0040] 6. Place the foundation bolt 6 and tighten the nut 9;

[0041] 7. Pouring concrete to form the foundation column section 3 and the foundation footing section 4.

[0042] In summary, the overhead transmission line rock inclined anchor rod foundation of the utility model adopts an inclined anchor rod scheme, the inclined anchor piles increase the anchor pile spacing, and the anchor rod specification no longer restricts the minimum spacing of the anchor piles, the undisturbed soil foundation pit diameter only needs to meet the construction operation space, under the same column diameter, the number of anchor piles can be greatly increased, thereby improving the upper limit of the maximum bearing capacity of the foundation, expanding the application range of the rock anchor rod foundation, and greatly improving the mechanization construction rate in mountainous areas. In the overhead transmission line rock inclined anchor rod foundation of the utility model, the anchor bar is directly welded and fixed with the anchor disc, and the anchor disc and the foundation bolt are fastened with a nut, so that the foundation force can be directly transmitted to the anchor pile through the foundation bolt, and the force transmission is more direct. Meanwhile, since the foundation bolt and the anchor disc are fastened with a nut, the minimum requirement for the anchoring length of the foundation bolt is no longer limited, the amount of the foundation bolt can be effectively reduced, the anchoring length of the foundation bolt can be effectively reduced, and the weight of the foundation bolt can be saved. The overhead transmission line rock inclined anchor rod foundation of the utility model adopts an undisturbed column foundation pit hole, no longer adopts a traditional large-excavation pile cap type anchor rod foundation, greatly reduces the amount of excavated earthwork, and makes the foundation construction more environmentally friendly. Since the undisturbed soil foundation pit is excavated, the influence of the thick overburden layer is no longer limited, the anchor rod foundation of the utility model can still be used when the overburden layer is greater than 3m, and the requirement of the specification for the minimum depth of 0.5m embedded in the rock can be more easily met in the area with a thick overburden layer of soil, and the column only needs to be deepened. The utility model conforms to the calculation theory of the composite anchor rod, the undisturbed soil column part can consider the beneficial effect of the excavation foundation, the amount of foundation concrete, the amount of foundation pit excavation, and the amount of surplus soil transportation are reduced, and the goal of "resource-saving and environment-friendly" is achieved.

[0043] A related existing patent is a Chinese utility model patent with the patent number CN219261097U, "Overhead transmission line variable cross-section rock anchor rod foundation", which increases the shear capacity of the anchor pile at the top by increasing the diameter of the anchor pile, resists the influence of the horizontal force of the foundation, avoids the requirement of the anchor rod foundation industry specification for the embedding of the anchor rod foundation pile cap into the rock, reduces the pile cap embedding depth in the area with a thick overburden layer, reduces the amount of earth excavation, and thereby expands the application range of the rock anchor rod foundation. The main technical features of the present scheme and the above-mentioned patent are different, the present scheme can greatly expand the application range of the rock anchor rod foundation while reducing the amount of earthwork and embedding the foundation bottom into the rock.

[0044] It needs to be explained that the utility model can effectively increase the number of anchor piles under the same basic section, and the anchor piles are no longer limited by the minimum distance of the drilling position, the anchor piles are provided with an outward inclination angle of 10°-25°, the anchor pile depth is increased, the anchor pile distance is gradually enlarged with the depth, and the minimum anchor pile distance is the starting point of the anchor pile calculation depth. As known from the above description, when the anchor pile distance is not met, the anchor pile calculation depth starting point is from the bottom of the foundation to the anchor pile, the anchor pile concrete and anchor reinforcement length in this range are the cost increase to meet the structural requirements and do not participate in the foundation calculation, but actually have a beneficial effect on the overall stress of the foundation. Generally in the mountain, the overlying rock weathering degree is higher, if the rock anchor specification anchor pile anchoring rock quality grade requirement is not met, this part of rock needs to be treated by anchor pile lengthening and penetration, at this time, the anchor pile lengthening caused by the anchor pile distance structure control can correspondingly offset the cost increase problem.

Claims

1. An overhead power transmission line rock inclined anchor foundation, characterized in that, The anchor pile (5) is provided with an anchor bar (8) in the anchor pile (5), the upper end of the anchor bar (8) is exposed to the upper end of the anchor pile (5), and the upper end of the anchor bar (8) is connected with the anchor disc (7).

2. The rock inclined anchor foundation for overhead transmission lines according to claim 1, characterized in that, The upper part of the foundation body is a foundation column body section (3), the lower end of the foundation column body section (3) is connected with a foundation bottom expanding section (4), the cross-sectional dimension of the lower end of the foundation bottom expanding section (4) is greater than the cross-sectional dimension of the upper end of the foundation bottom expanding section (4) and greater than the cross-sectional dimension of the foundation column body section (3); the anchor disc (7) is located in the foundation column body section (3), and the upper end of the anchor pile (5) is located in the foundation bottom expanding section (4).

3. The overhead power line rock inclined anchor foundation according to claim 2, characterized in that, The foundation bottom expanding section (4) is located below the rock section (2) below the natural ground (1) in whole or in part.

4. The overhead power line rock inclined anchor foundation according to claim 2, characterized in that, The foundation column body section (3) is in a cylindrical shape, the foundation bottom expanding section (4) is in a circular truncated cone shape, the central axis of the foundation column body section (3) and the foundation bottom expanding section (4) are coincident, and the cross-sectional dimension of the foundation column body section (3) is consistent with the cross-sectional dimension of the upper end of the foundation bottom expanding section (4).

5. The overhead power line rock inclined anchor foundation according to claim 1, characterized in that, The anchor disc (7) is distributed with a plurality of vertical through anchor bolt holes, and a plurality of anchor bolts (6) pass through the anchor bolt holes one by one in a corresponding manner; the lower end of the anchor bolt (6) is threadedly connected with a nut (9) sleeved, and the nut (9) is located below the anchor disc (7).

6. An overhead power line rock inclined anchor foundation according to any one of claims 1-5, characterized in that, The inclination angle of the anchor pile (5) relative to the vertical direction is 10°-25°.

7. An overhead power line rock inclined anchor foundation according to any one of claims 1-5, characterized in that, The anchor pile (5) is circumferentially uniformly distributed.

8. An overhead power line rock inclined anchor foundation according to any one of claims 1-5, characterized in that, The inclination angle of the anchor bar (8) is the same as the inclination angle of the anchor pile (5) where the anchor bar (8) is located.

9. An overhead power line rock inclined anchor foundation according to any one of claims 1-5, characterized in that, The spacing between the upper ends of adjacent anchor piles (5) is less than 2.5 times the diameter of the anchor pile (5).

10. The overhead power line rock inclined anchor foundation according to any one of claims 1-5, characterized in that, The upper end of the anchor bolt (6) is connected with a tower foot plate of an overhead transmission line.

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