CN114941322A - Construction method for repairing protection slope of protective ground drop upper cover support pile - Google Patents

Abstract

The invention relates to the field of civil engineering, in particular to a construction method for repairing a protection slope of a drop-over upper cover supporting pile in a protected area, which comprises the following steps of 1, mounting a tripod; step 2, setting up an operation frame; step 2.1, erecting a floor sweeping rod and a vertical rod; step 2.2, lengthening the vertical rod; step 2.3, guard rails; step 3, surface layer repairing: after preliminary fixing, the surface layer of the original subway upper cover supporting pile is repaired, and the concrete strength of the original subway upper cover supporting pile is guaranteed. Construction is carried out through the steps, the problem that the subway upper cover supporting pile cracks due to construction can be effectively solved, and the method is safer and more convenient for the related art. Because original subway upper cover fender pile is original building structure, surely can not demolish. Therefore, the method carries out the first frame body reinforcement on the support pile and carries out the concrete pouring reinforcement for the second time, thereby protecting the stability of the original structure of the subway upper cover to a great extent.

Description

Construction method for repairing protection slope of protective ground drop upper cover support pile

Technical Field

The invention relates to the field of civil engineering, in particular to a construction method for repairing a protection slope of a drop-over upper cover supporting pile in a protected area.

Background

Along with the development of urban economy, more and more buildings have the problem of stack in the space, close to, especially, in urban building, often take place superstructure's foundation ditch and the close problem of original fender pile of leaving over that exists on subway reserved structure upper portion. Due to the obvious construction disturbance of the on-site foundation pit supporting machinery, the complex surrounding environment, the long construction period, the unpredictable nature environment factors and other factors, the structural system and the surrounding environment are in a changing and unstable state, and thus, the foundation pit can be damaged locally.

Disclosure of Invention

The invention aims to repair the cracking and falling phenomena of the fender pile protection slope while protecting the upper structure area of the subway.

In order to achieve the above object, the present invention is realized by:

a construction method for repairing the slope protection of a drop-over upper cover supporting pile in a protected area comprises

Step 1, mounting the tripod

Welding bolts to reserved steel bar back bars at intervals of 2.1m, then installing a tripod, wherein the tripod is installed at an interval of 2.1m and an installation height of 6.8m, the interval of a template is reserved before installation, and the tripod is used for template reinforcement after the support piles are repaired;

step 2, setting up an operation frame

Setting parameters, setting the height to the crack of a slope protection surface layer, wherein the vertical rods are single vertical rods, the distance between each vertical rod and a supporting pile is 0.3m, the longitudinal row spacing and the transverse row spacing are respectively 1.5m, 1.5m and 0.9m, the transverse row spacing is 1.5m, the step spacing is 1.5m, horizontal and vertical cross braces are arranged, and inclined polishing braces are arranged on the north side;

step 2.1, erecting floor sweeping rods and vertical rods

Firstly, placing a longitudinal sweeping rod, wherein the height of the longitudinal sweeping rod from the bottom surface of the foundation is 200mm, and then, fastening the longitudinal sweeping rod with a vertical rod and then building a transverse sweeping rod;

after the vertical rods are erected, the large sweeping cross rod and the small sweeping cross rod can be arranged to form a stable frame;

when the vertical rod foundations are not at the same height, the longitudinal floor sweeping rod at the high position needs to be extended to the low position for two spans to be fixed with the vertical rod, the height difference is not more than 1m, and the distance from the axis of the vertical rod above the side slope to the side slope is not less than 500 mm;

the vertical deviation of the vertical rod is controlled to be not more than 1/400 of the height of the vertical rod;

when the foundations of the vertical rods are not at the same height, the vertical floor sweeping rod at a high position needs to be extended to a low position and fixed with the vertical rod, the height difference is not more than 1m, and the distance from the axis of the vertical rod above a side slope to the side slope is not less than 500 mm;

step 2.2, extension of the vertical rod

When the vertical rods are in butt joint for long, the butt joint fasteners of the vertical rods are arranged in a staggered mode, the joints of two adjacent vertical rods are not arranged in a synchronous mode, and the staggered distance of two separated joints separating one vertical rod in the synchronous mode in the height direction is not smaller than 500mm (namely b is larger than or equal to 500 mm); the distance from the center of each joint to the main node is not more than the stepped distance 1/3 (namely h/3), and the distance from the edge of the cover plate of the end fastener to the end of the lapping longitudinal horizontal rod is not less than 100 mm;

step 2.3, guard rail

From the second step, an outer protective railing must be arranged at the height of 0.6m and 1.2m respectively, and the scaffold railing must be always higher than the working layer by more than 1.2 m. The end of the scaffold is provided with a railing end socket;

step 3, surface layer repairing: after preliminary fixing, repairing the surface layer of the original subway upper cover supporting pile to ensure the concrete strength of the original subway upper cover supporting pile;

3.1, removing by adopting a manual electric pick, performing chiseling from top to bottom, wherein the chiseling height is not more than 2m each time, and performing net hanging and spraying repairing on the chiseled side slope in time;

step 3.2, trimming the slope surface before hanging the mesh, leveling all uneven places, ensuring that the reinforcing mesh is positioned on the same plane, and ensuring that the thickness of sprayed concrete is consistent;

3.3, hanging a reinforcing mesh, wherein the reinforcing mesh is a reinforcing mesh with the diameter of phi 6@150mm multiplied by 150mm, the diameter of phi 22 is fixed by a reinforcing steel bar, and the lap joint length is more than 35 d;

3.4, spraying C20 concrete, wherein during spraying operation, the air volume of an air compressor is not less than 9m3/min, the air pressure is 0.2-0.5 Mpa, the water pressure of a spray head is not less than 0.15Mpa, the spraying distance is controlled to be 0.6-1.0 m, the initial setting time and the final setting time of the concrete are controlled to be 10-20 min by an external accelerator, and the spraying thickness is more than or equal to 50 mm;

step 3.5, trowelling and calendaring by using 1:2.5 cement mortar;

step 3.6, maintenance: standard maintenance is carried out according to the standard requirement, and after the spraying is finished, plastic cloth and a straw curtain are used for covering;

and 3.7, after the previous section of sprayed concrete construction is finished, next section of concrete dismantling construction can be carried out, and the height of each section cannot exceed 2 meters until the whole slope surface is completely sprayed again.

The repairing method disclosed by the invention has the following advantages:

1. construction is carried out through the steps, the problem that the subway upper cover supporting pile cracks due to construction can be effectively solved, and the construction method is safer and more convenient for the related technology.

2. Because original subway upper cover fender pile is original building structure, surely can not demolish. Consequently carry out the first support body to a fender pile and consolidate, carry out concrete placement and consolidate the second time, protected the stability of the original structure of subway upper cover to a very big degree.

Drawings

Fig. 1 is a tripod support schematic diagram of a repair support pile.

Fig. 2 is a schematic elevation view of the operating frame.

Figure 3 is a schematic of pole set up.

Detailed Description

The invention is further illustrated by the following specific examples.

A construction method for restoring a protection slope of a drop-over upper cover support pile in a protected area comprises the following steps:

1. as shown in figure 1, the mounting tripod

And welding bolts to the reserved steel bar back ribs at intervals of 2.1m, and then installing the triangular supports, wherein the installation interval of the triangular supports is 2.1m, and the installation height is 6.8 m. The interval of the template is reserved before installation, and the tripod is used as the template for reinforcement after the support pile is repaired. This step is at first tentatively fixed to a fender pile, prevents that a fender pile from damaging because of the fracture reason, guarantees the first half structure of subway, ensures normal construction.

2. As shown in fig. 2, the operation frame is set up

Setting up parameters, setting up the height to be 8m (to the crack of a slope protection surface layer), setting up a single vertical rod, setting up the single rod, setting up the single vertical rod, setting up the horizontal rod, setting up the horizontal rod, setting up the slope. The step is operated on the basis of the previous step, so that workers can conveniently carry out the next step of process construction, and the safety is ensured.

(1) As shown in fig. 3, the floor sweeping pole and the vertical pole are erected

The vertical sweeping rod is placed firstly, the height of the vertical sweeping rod from the bottom surface of the foundation is 200mm, and then the vertical sweeping rod is fastened and then the horizontal sweeping rod is erected.

After the vertical rods are erected, the large sweeping cross rod and the small sweeping cross rod can be arranged to form a stable frame.

When the vertical rod foundations are not at the same height, the longitudinal floor sweeping rod at the high position needs to be extended to the low position for two spans to be fixed with the vertical rod, and the height difference is not more than 1 m. The distance from the axis of the upright rod above the side slope to the side slope is not less than 500 mm.

The vertical deflection of the uprights should be controlled to be no greater than 1/400 of the elevation.

The scaffold must be provided with a floor sweeping rod, and the longitudinal floor sweeping rod is fixed on a vertical rod at a position which is far away from the base and has an upper skin not more than 200mm by adopting a right-angle fastener. When the vertical pole foundations are not at the same height, the vertical floor sweeping pole at the high position needs to be extended to the low position to be fixed with the vertical pole, and the height difference is not more than 1 m. The distance from the axis of the upright rod above the side slope to the side slope is not less than 500 mm.

(2) Extension of vertical rod

When the vertical rods are in butt joint for long, the butt joint fasteners of the vertical rods are arranged in a staggered mode, the joints of two adjacent vertical rods are not arranged in a synchronous mode, and the staggered distance of two separated joints separating one vertical rod in the synchronous mode in the height direction is not smaller than 500mm (namely b is larger than or equal to 500 mm); the distance from the center of each joint to the main node is not longer than 1/3 (i.e. h/3) with walking distance. The distance from the edge of the end fastener cover plate to the end of the overlapping longitudinal horizontal rod should not be less than 100 mm.

(3) Protective railing

From the second step, an outer guard rail must be arranged at each of the 0.6m and 1.2m heights. The scaffold railing must be always higher than the working floor by more than 1.2 m. The end of the scaffold is provided with a railing end socket.

3. Surface layer repairing (after preliminary fixing, repairing the surface layer of the original subway upper cover supporting pile to ensure the concrete strength of the original subway upper cover supporting pile)

The repairing process comprises the following steps: demolishing concrete → trimming slope → hanging reinforcing mesh → spraying concrete → maintaining

(1) And the demolition construction is carried out by adopting a manual electric pick to chisel the slope from top to bottom, the chiseling height is not more than 2m each time, and the chiseled slope is subjected to net hanging and spraying repair in time.

(2) The slope is trimmed before the net is hung, uneven places are all leveled, the reinforcing steel bar nets are ensured to be positioned on the same plane, and the thickness of the sprayed concrete is consistent.

(3) And (3) hanging a reinforcing mesh, wherein the reinforcing mesh is a reinforcing mesh with the diameter of 6@150mm multiplied by 150mm, the reinforcing mesh is fixed by 22 reinforcing steel bars, and the lap joint length is more than 35 d.

(4) C20 concrete is sprayed, during spraying operation, the air volume of an air compressor is not less than 9m3/min, the air pressure is 0.2-0.5 Mpa, the water pressure of a spray head is not less than 0.15Mpa, the spraying distance is controlled to be 0.6-1.0 m, the initial setting time and the final setting time of the concrete are controlled to be 10-20 min through an external accelerator, and the spraying thickness is larger than or equal to 50 mm.

(5) Troweling and calendering with 1:2.5 cement mortar (to meet the requirement of waterproof external-protection internal-pasting base layer)

(6) And (5) maintenance: and performing standard maintenance according to the standard requirement, and covering with plastic cloth and a straw curtain after spraying.

(7) After the previous section of sprayed concrete construction is finished, next section of concrete dismantling construction can be carried out, the height of each section cannot exceed 2 meters until the whole slope surface is completely sprayed again.

Claims (1)

1. A construction method for restoring a protection slope of an upper cover supporting pile falling in a protected area is characterized by comprising the following steps: comprises that

Step 1, mounting the tripod

Welding bolts to reserved steel bar back bars at intervals of 2.1m, then installing tripods, wherein the installation distance of the tripods is 2.1m, the installation height is 6.8m, the distance of templates is reserved before installation, and the tripods are used for template reinforcement after the support piles are repaired;

step 2, setting up an operation frame

Setting parameters, setting the height to the crack of a slope protection surface layer, wherein the vertical rods adopt single vertical rods, the distance between the vertical rods and a support pile is 0.3m, the longitudinal and transverse row distances are 1.5m, 1.5m and 0.9m respectively, the transverse row distances are 1.5m, the step distance is 1.5m, horizontal and vertical shear braces are arranged, and an inclined throwing brace is arranged on the north side;

step 2.1, erecting floor sweeping rods and vertical rods

Firstly, placing a longitudinal sweeping rod, wherein the height of the longitudinal sweeping rod from the bottom surface of the foundation is 200mm, and then, fastening the longitudinal sweeping rod with a vertical rod and then building a transverse sweeping rod;

after the vertical rods are erected, the large sweeping cross rod and the small sweeping cross rod can be arranged to form a stable frame;

when the vertical rod foundations are not at the same height, the longitudinal floor sweeping rod at the high position needs to be extended to the low position for two spans to be fixed with the vertical rod, the height difference is not more than 1m, and the distance from the axis of the vertical rod above the side slope to the side slope is not less than 500 mm;

the vertical deviation of the vertical rod is controlled to be not more than 1/400 of the height of the vertical rod;

when the vertical rod foundations are not at the same height, the vertical sweeping rod at a high position needs to be extended to a lower position and fixed with the vertical rod, the height difference is not more than 1m, and the distance from the axis of the vertical rod above the side slope to the side slope is not less than 500 mm;

step 2.2, extension of the vertical rod

When the vertical rods are in butt joint for long, the butt joint fasteners of the vertical rods are arranged in a staggered mode, the joints of two adjacent vertical rods are not arranged in a synchronous mode, and the staggered distance of two separated joints separating one vertical rod in the synchronous mode in the height direction is not smaller than 500mm (namely b is larger than or equal to 500 mm); the distance from the center of each joint to the main node is not more than 1/3 (i.e. h/3) with step distance, and the distance from the edge of the cover plate of the end fastener to the end of the lapping longitudinal horizontal rod is not less than 100 mm;

step 2.3, guard rail

From the second step, an outer protective railing must be arranged at the height of 0.6m and 1.2m respectively, and the scaffold railing must be always higher than the working layer by more than 1.2 m. The end of the scaffold is provided with a railing end socket;

step 3, surface layer repairing: after preliminary fixing, repairing the surface layer of the original subway upper cover supporting pile to ensure the concrete strength of the original subway upper cover supporting pile;

3.1, removing by adopting a manual electric pick, performing chiseling from top to bottom, wherein the chiseling height is not more than 2m each time, and performing net hanging and spraying repairing on the chiseled side slope in time;

step 3.2, trimming the slope surface before hanging the mesh, leveling all uneven places, ensuring that the reinforcing mesh is positioned on the same plane, and ensuring that the thickness of sprayed concrete is consistent;

step 3.3, hanging a reinforcing mesh, wherein the reinforcing mesh is made of a reinforcing mesh with the diameter of phi 6@150mm multiplied by 150mm, and a reinforcing steel bar with the diameter of phi 22 is fixed, and the lap joint length is more than 35 d;

3.4, spraying C20 concrete, wherein during spraying operation, the air quantity of an air compressor is not less than 9m3/min, the air pressure is 0.2-0.5 Mpa, the water pressure of a spray head is not less than 0.15Mpa, the spraying distance is controlled to be 0.6-1.0 m, the initial setting time and the final setting time of the concrete are controlled to be 10-20 min through an external accelerator, and the spraying thickness is more than or equal to 50 mm;

step 3.5, troweling and calendaring by using cement mortar in a ratio of 1: 2.5;

step 3.6, maintenance: standard maintenance is carried out according to the standard requirement, and after the spraying is finished, plastic cloth and a straw curtain are used for covering;

and 3.7, after the previous section of sprayed concrete construction is finished, next section of concrete dismantling construction can be carried out, and the height of each section cannot exceed 2 meters until the whole slope surface is completely sprayed again.

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