阅读说明：本技术 一种深基坑开挖区既有高压线杆原位保护方法 (In-situ protection method for existing high-voltage line pole in deep foundation pit excavation area ) 是由 郭文峰 张玉波 隗磊 闻艳萍 李长贵 于 2019-08-15 设计创作，主要内容包括：本发明属于市政工程技术领域,尤其涉及一种深基坑开挖区既有高压线杆原位加固保护方法,所述方法包括：步骤1,测定桩位；步骤2,钻固定孔；步骤3,钢筋束制作；步骤4,钢筋束安装；步骤5,注浆：步骤5.1,拌制水泥浆：水泥浆水灰比为0.8:1～1:1,采用水泥浆搅拌机拌制；步骤5.2,采用φ2.5聚乙烯塑料管作为注浆管,沿钢筋束中部穿至距离固定孔底部50～80cm处,用铁丝牢固的固定在钢筋束上,自下而上连续灌注浆液,注满为止,拔出注浆管,锚筋桩完成；步骤6,整体焊接,将锚筋束外露部分整体呈环状焊接形成整体。本发明所述保护方法能够确保施工期既有高压线杆的正常运行和施工人员的防触电安全,并使所述高压线杆更为牢固。(The invention belongs to the technical field of municipal engineering, and particularly relates to an in-situ reinforcement and protection method for an existing high-voltage line pole in a deep foundation pit excavation area, which comprises the following steps: step 1, pile positions are measured; step 2, drilling a fixing hole; step 3, manufacturing a steel bar bundle; step 4, mounting the reinforcing steel bar bundles; and step 5, grouting: step 5.1, mixing cement paste: the water-cement ratio of the cement paste is 0.8: 1-1: 1, and the cement paste is mixed by a cement paste mixer; step 5.2, adopting a phi 2.5 polyethylene plastic pipe as a grouting pipe, penetrating the grouting pipe to a position 50-80 cm away from the bottom of the fixing hole along the middle part of the steel bar bundle, firmly fixing the grouting pipe on the steel bar bundle by using an iron wire, continuously pouring grout from bottom to top until the grouting pipe is full, pulling out the grouting pipe, and finishing the anchor bar pile; and 6, integrally welding, namely, integrally welding the exposed part of the anchor bar bundle into a whole in an annular shape. The protection method can ensure the normal operation of the existing high-voltage line pole and the electric shock prevention safety of constructors in the construction period, and enables the high-voltage line pole to be firmer.)

1. The in-situ reinforcement and protection method for the existing high-voltage line pole in the deep foundation pit excavation area is characterized by comprising the following steps of:

step 1, pile position determination: paying off the line pole to be reinforced with the radius of 1.5m as the circle center, determining the range of the enclosure anchor bar pile, and marking the pile positions one by one on the circular line according to the distance of 30 cm;

step 2, drilling a fixing hole: digging soil at the pile position marked in the step 1 by using a Luoyang shovel to form a fixed hole, wherein the depth of the fixed hole is increased by 5m on the basis of the depth of the foundation pit to be excavated, and the aperture of the fixed hole is 15 cm;

step 3, manufacturing the steel bar bundles: cutting a phi 25 steel bar into supporting ribs with the length of 4.5m at each section, cutting a phi 16 steel bar into reinforcing ribs with the length of 0.1m at each section, arranging the supporting ribs in a delta shape with 3 supporting ribs, spacing every two reinforcing ribs by 0.1m, welding and fixing the reinforcing ribs by 3 reinforcing ribs, and welding the reinforcing ribs at the spacing distance of 1.5m to form a whole; the positioning ribs are made into a shape like a Chinese character ji by adopting phi 10 steel bars with the length of 40cm, are welded on the outer sides of the supporting ribs, are arranged in groups of every 2m, and each group comprises 3 positioning ribs, so that the anchoring ribs are not directly contacted with the hole wall after being bound into the holes, and a protective layer is reserved;

step 4, mounting the reinforcing steel bar: hoisting the single-section steel bar bundle to the position above the fixing hole, vertically hoisting the steel bar bundle to the position in the fixing hole, lowering the steel bar bundle at a constant speed, and keeping the top of the steel bar bundle at 0.5m outside the fixing hole;

hoisting the next section of the reinforcing steel bar bundle to the position above the fixing hole, vertically arranging the reinforcing steel bar bundle, welding and fixing the reinforcing steel bar bundle and the previous reinforcing steel bar bundle, and lowering the reinforcing steel bar bundle at a constant speed, wherein 0.5m is reserved outside the fixing hole;

repeating the operation, mounting the reinforcing steel bar bundles to the bottoms of the fixing holes, and mounting the reinforcing steel bar bundles in each fixing hole;

and step 5, grouting:

step 5.1, mixing cement paste: the water-cement ratio of the cement paste is 0.8: 1-1: 1, and the cement paste is mixed by a cement paste mixer;

step 5.2, adopting a phi 2.5 polyethylene plastic pipe as a grouting pipe, penetrating the grouting pipe to a position 50-80 cm away from the bottom of the fixing hole along the middle part of the steel bar bundle, firmly fixing the grouting pipe on the steel bar bundle by using an iron wire, continuously pouring grout from bottom to top until the grouting pipe is full, pulling out the grouting pipe, and finishing the anchor bar pile;

and 6, integrally welding, wherein the exposed part of the anchor bar bundle is integrally annular, phi 16 steel bars are adopted to surround and weld one by one along the periphery of the exposed anchor bar bundle, the phi 16 steel bars are cut out to manufacture tie bars, and opposite anchor bar bundles are welded and fixed in a split-pulling manner to form an integral body.

2. The in-situ reinforcement and protection method for the existing high-voltage line pole in the deep foundation pit excavation area according to claim 1, wherein all the steps are organized and implemented within a safety distance range under the high-voltage line, and the specific construction safety distance is as follows: the safe distance of the high-voltage line below 1kV is 4 meters; the safe distance of the 1-10kV high-voltage line is 6 meters; the safe distance of the 35-110kV high-voltage line is 8 meters; the safe distance of the 154-220kV high-voltage line is 10 meters; the safe distance of the 350-500kV high-voltage line is 15 meters.

3. The in-situ reinforcement and protection method for the existing high-voltage line pole in the excavation area of the deep foundation pit according to claim 1, wherein in the step 3, the positioning steel bars are of a semicircular structure.

4. The method for in-situ reinforcement and protection of the existing high-voltage line pole in the excavation area of the deep foundation pit according to claim 1, wherein in the step 5.2, the grouting pipe is kept 0.5m below the surface of cement paste.

5. The in-situ reinforcement and protection method for the existing high-voltage wire rods in the excavation area of the deep foundation pit according to claim 1, wherein in the step 6, the high-voltage wire rods and the peripheral reinforcing steel bundles are welded and fixed one by using phi 16 reinforcing steel bars.

6. The in-situ reinforcement and protection method for the existing high-voltage line pole in the excavation area of the deep foundation pit according to claim 1, wherein the step 6 further comprises the following steps:

a wire rod steel sleeve is fixedly arranged on the high-voltage wire rod;

and C-shaped steel is welded on the wire rod steel sleeve and the anchor bar bundle which is annular as a whole.

7. The in-situ reinforcement and protection method for the existing high-voltage line pole in the excavation area of the deep foundation pit according to claim 1, wherein the step 6 further comprises the following steps:

a hoop is arranged at 2/3 of the height of the high-voltage line pole body, 3-5 pull rings are welded on the hoop, and the pull rings are fixed on the outer wall of the hoop in a central symmetry manner;

selecting an anchoring point on the ground in the direction opposite to the pull ring, and mounting a ground anchor on the anchoring point, wherein the anchoring point is outside the excavation area of the deep foundation pit, and the height of the anchoring point is lower than that of the hoop;

and connecting the pull ring and the ground anchor in the direction opposite to the pull ring by using a steel wire rope, and tensioning the steel wire rope.

8. The in-situ reinforcement and protection method for the existing high-voltage wire rods in the deep foundation pit excavation area as claimed in claim 1, wherein the step 1 further comprises the step of measuring the verticality of the high-voltage wire rods, if the verticality is greater than 10/300mm, the high-voltage wire rods are aligned to the verticality which is not greater than 10/300mm, and then the construction of drilling fixing holes is carried out.

9. The in-situ reinforcement and protection method for the existing high-voltage line pole in the excavation area of the deep foundation pit according to claim 1, wherein the step 1 further comprises the following steps:

rolling a circular ring area which takes a wire pole to be reinforced as a circle center and has a radius of 60 cm;

drilling a cast-in-place pile hole in the annular area, wherein the aperture of the cast-in-place pile hole is 6-8cm, and the depth of the cast-in-place pile hole is 100 cm;

pouring concrete into the cast-in-place pile hole, wherein the concrete comprises 1 part of water, 1 part of cement and 1 part of sand, and the particle size of the sand is 1.0-2.0 cm;

and when the concrete in the cast-in-place pile hole is not completely solidified, pouring concrete into the circular ring area to enable the poured concrete to surround the periphery of the wire pole to be reinforced, and building the poured concrete into an inverted funnel shape till the poured concrete is solidified.

Technical Field

The invention belongs to the technical field of municipal engineering, and relates to an in-situ reinforcement and protection method for an existing high-voltage line pole in a deep foundation pit excavation area.

Background

The protection of high-voltage line poles around the deep foundation pit is mostly solved by adopting a changing mode, if the changing mode is difficult, the modes of steel sheet piles, jet grouting piles and the like are mostly adopted to carry out enclosure reinforcement on the excavation edge of the foundation pit so as to ensure the safety of the line poles around the foundation pit. In order to ensure the safety of enclosure construction, the construction of large equipment such as steel sheet piles, jet grouting piles and the like has special requirements on the level of a high-voltage line, clearance safety distance and the like, and the construction has more limited conditions and great potential safety hazard.

The existing high-voltage line pole in the deep foundation pit excavation area needs to be solved by adopting a relocation method, but the line relocation construction of the power department often has the characteristics of complex procedures, low efficiency, long implementation period and the like, and the requirements on the construction progress of the deep foundation pit are difficult to meet. Before the high-voltage line pole in the deep foundation pit excavation area scope has not been changed and is accomplished, how to guarantee not influencing deep foundation pit construction progress in, can also ensure existing high-voltage line's normal operating and constructor's protection against electric shock safety, is the technical problem that the skilled person needs a urgent need to solve.

The Chinese patent application numbers are: the patent of CN201510430135.6 discloses a method for reinforcing and protecting a foundation of a utility pole adjacent to a deep foundation pit, which comprises the following steps: s1: driving a high-pressure jet grouting pile into one side of the telegraph pole close to the foundation pit along the direction of the underground wall; s2: inserting a plurality of channel steels into the high-pressure jet grouting pile; s3: a plurality of channel steel is driven into the two sides of the telegraph pole in a direction perpendicular to the underground wall, and the channel steel with three sides forms a surround on three sides of the telegraph pole; s4: and arranging a steel purlin along the outer side of the channel steel, and welding the steel purlin and the steel channel into a whole. The method for foundation reinforcement of the telegraph pole by the high-pressure jet grouting pile and the channel steel ensures the safety of the telegraph pole and constructors in the excavation process of the foundation pit, and does not need a long process for transferring the telegraph pole by an electric power department, thereby accelerating the construction progress, saving the cost, having high flexibility, being suitable for various construction conditions, but not being directly suitable for protection of the existing high-pressure line pole in the excavation area of the deep foundation pit.

Disclosure of Invention

The invention aims to provide an in-situ reinforcement and protection method for an existing high-voltage line pole in a deep foundation pit excavation area, so that the normal operation of the existing high-voltage line pole and the electric shock prevention safety of construction personnel in a construction period are ensured, and the high-voltage line pole is firmer.

The in-situ reinforcement and protection method for the existing high-voltage line pole in the deep foundation pit excavation area comprises the following steps:

step 1, pile position determination: paying off the line pole to be reinforced with the radius of 1.5m as the circle center, determining the range of the enclosure anchor bar pile, and marking the pile positions one by one on the circular line according to the distance of 30 cm;

step 2, drilling a fixing hole: digging soil at the pile position marked in the step 1 by using a Luoyang shovel to form a fixed hole, wherein the depth of the fixed hole is increased by 5m on the basis of the depth of the foundation pit to be excavated, and the aperture of the fixed hole is 15 cm;

step 3, manufacturing the steel bar bundles: cutting a phi 25 steel bar into supporting ribs with the length of 4.5m at each section, cutting a phi 16 steel bar into reinforcing ribs with the length of 0.1m at each section, arranging the supporting ribs in a delta shape with 3 supporting ribs, spacing every two reinforcing ribs by 0.1m, welding and fixing the reinforcing ribs by 3 reinforcing ribs, and welding the reinforcing ribs at the spacing distance of 1.5m to form a whole; the positioning ribs are made into a shape like a Chinese character ji by adopting phi 10 steel bars with the length of 40cm, are welded on the outer sides of the supporting ribs, are arranged in groups of every 2m, and each group comprises 3 positioning ribs, so that the anchoring ribs are not directly contacted with the hole wall after being bound into the holes, and a protective layer is reserved;

step 4, mounting the reinforcing steel bar: hoisting the single-section steel bar bundle to the position above the fixing hole, vertically hoisting the steel bar bundle to the position in the fixing hole, lowering the steel bar bundle at a constant speed, and keeping the top of the steel bar bundle at 0.5m outside the fixing hole;

hoisting the next section of the reinforcing steel bar bundle to the position above the fixing hole, vertically arranging the reinforcing steel bar bundle, welding and fixing the reinforcing steel bar bundle and the previous reinforcing steel bar bundle, and lowering the reinforcing steel bar bundle at a constant speed, wherein 0.5m is reserved outside the fixing hole;

repeating the operation, mounting the reinforcing steel bar bundles to the bottoms of the fixing holes, and mounting the reinforcing steel bar bundles in each fixing hole;

and step 5, grouting:

step 5.1, mixing cement paste: the water-cement ratio of the cement paste is 0.8: 1-1: 1, and the cement paste is mixed by a cement paste mixer;

step 5.2, adopting a phi 2.5 polyethylene plastic pipe as a grouting pipe, penetrating the grouting pipe to a position 50-80 cm away from the bottom of the fixing hole along the middle part of the steel bar bundle, firmly fixing the grouting pipe on the steel bar bundle by using an iron wire, continuously pouring grout from bottom to top until the grouting pipe is full, pulling out the grouting pipe, and finishing the anchor bar pile;

and 6, integrally welding, wherein the exposed part of the anchor bar bundle is integrally annular, phi 16 steel bars are adopted to surround and weld one by one along the periphery of the exposed anchor bar bundle, the phi 16 steel bars are cut out to manufacture tie bars, and opposite anchor bar bundles are welded and fixed in a split-pulling manner to form an integral body.

Further, all the steps are organized and implemented within a safe distance range under the high-voltage line, and the specific construction safe distance is as follows: the safe distance of the high-voltage line below 1kV is 4 meters; the safe distance of the 1-10kV high-voltage line is 6 meters; the safe distance of the 35-110kV high-voltage line is 8 meters; the safe distance of the 154-220kV high-voltage line is 10 meters; the safe distance of the 350-500kV high-voltage line is 15 meters.

Further, in step 3, the positioning steel bars adopt a semicircular structure.

Further, in step 5.2, the grout tube is held 0.5m below the grout surface.

Further, in step 6, the high-voltage wire rods and the peripheral tendons are welded and fixed one by using phi 16 steel bars.

Further, step 6 includes the following steps:

a wire rod steel sleeve is fixedly arranged on the high-voltage wire rod;

and C-shaped steel is welded on the wire rod steel sleeve and the anchor bar bundle which is annular as a whole.

Further, step 6 includes the following steps:

a hoop is arranged at 2/3 of the height of the high-voltage line pole body, 3-5 pull rings are welded on the hoop, and the pull rings are fixed on the outer wall of the hoop in a central symmetry manner;

selecting an anchoring point on the ground in the direction opposite to the pull ring, and mounting a ground anchor on the anchoring point, wherein the anchoring point is outside the excavation area of the deep foundation pit, and the height of the anchoring point is lower than that of the hoop;

and connecting the pull ring and the ground anchor in the direction opposite to the pull ring by using a steel wire rope, and tensioning the steel wire rope.

Further, the step 1 also comprises the step of measuring the verticality of the high-voltage line rod, if the verticality is larger than 10/300mm, the high-voltage line rod is firstly aligned until the verticality is not larger than 10/300mm, and then the construction of drilling a fixing hole is carried out.

Further, step 1 also includes the following steps:

rolling a circular ring area which takes a wire pole to be reinforced as a circle center and has a radius of 60 cm;

drilling a cast-in-place pile hole in the annular area, wherein the aperture of the cast-in-place pile hole is 6-8cm, and the depth of the cast-in-place pile hole is 100 cm;

pouring concrete into the cast-in-place pile hole, wherein the concrete comprises 1 part of water, 1 part of cement and 1 part of sand, and the particle size of the sand is 1.0-2.0 cm;

and when the concrete in the cast-in-place pile hole is not completely solidified, pouring concrete into the circular ring area to enable the poured concrete to surround the periphery of the wire pole to be reinforced, and building the poured concrete into an inverted funnel shape till the poured concrete is solidified.

The invention has the beneficial effects that:

1. according to the in-situ reinforcement and protection method for the existing high-voltage wire rods in the deep foundation pit excavation area, the steel bar bundles are arranged around the wire rods to be reinforced and are subjected to grouting reinforcement, so that the operation safety of a power line in the bridge foundation construction and the deep foundation pit excavation construction process is ensured.

2. The in-situ reinforcement and protection method for the existing high-voltage line pole in the deep foundation pit excavation area can effectively provide in-situ protection for the existing high-voltage line pole in the deep foundation pit excavation area, and is simple in process, economical, applicable, safe and reliable.

3. According to the in-situ reinforcement and protection method for the existing high-voltage line pole in the deep foundation pit excavation area, the high-voltage line pole is firmer through the construction steps of drilling a cast-in-place pile hole in the circular ring area, grouting and pouring concrete into the circular ring area.

Drawings

Fig. 1 is a schematic structural diagram of a reinforcement bundle in the method for in-situ reinforcement and protection of an existing high-voltage line pole in an excavation area of a deep foundation pit;

fig. 2 is a sectional view of a reinforcement bundle in the method for in-situ reinforcement and protection of an existing high-voltage line pole in an excavation area of a deep foundation pit.

In the figure: 1-reinforcing bar bundle, 11-supporting bar, 12-reinforcing bar and 13-positioning bar.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments, it being understood that the embodiments and features of the embodiments of the present application can be combined with each other without conflict.