CN110259090A - A kind of construction method of novel pull-up builder's jack - Google Patents

Abstract

The invention discloses a construction method of a novel pull-up cantilevered scaffold, which comprises the following steps: (1) pre-embedding in the floor; (2) anti-slip vertical poles; (3) installing I-beams; (4) erecting scaffolds; (5) Acceptance and monitoring; (6) Remove scaffolding. Compared with the traditional cantilevering method, the pull-up cantilevered scaffolding of the present invention has the characteristics of short construction period, saving steel materials, high safety factor, good anti-seepage of outer walls, and the like. The pull-up cantilevered scaffolding successfully applied in construction can not only improve the safety performance of construction, but also speed up the turnover of materials, thereby reducing construction costs, reducing safety risks, and achieving objective economic benefits.

Description

A new construction method of pull-up cantilevered scaffolding

technical field

The invention belongs to the field of building construction, and in particular relates to a construction method of a novel pull-up cantilevered scaffold.

Background technique

In recent years, with the rapid development of my country's economy, my country's construction industry has made great progress, and the number and scale of various construction projects in cities have increased significantly. In the process of engineering construction, the construction of external scaffolding is an extremely important link, and its construction technology directly affects the progress, safety and cost of the project. Therefore, construction enterprises should pay attention to the research on external scaffolding construction technology, continue to optimize design, develop and innovate on the existing basis, and use better external frame structures to promote the development of the construction industry.

Contents of the invention

Purpose of the invention: In order to solve the deficiencies of the prior art, the present invention provides a construction method of a new pull-up cantilevered scaffold.

Technical solution: A construction method for a new type of pull-up cantilevered scaffolding, including the following steps:

(1) Embedded in this layer

Before the outer formwork of the cantilevered floor beams and columns is molded, the position of each I-beam is determined and marked, and then the master worker is arranged to weld the pre-prepared 300mm diameter galvanized pipe to the beams and columns. . 2 at each place, used as the fixing bolt hole of the I-beam, leaving a hole in the lighting well with walls on both sides, the I-beam can be directly penetrated, no need to set the tie rod;

(2) Pole anti-skid

After pouring the concrete of the cantilever layer, remove the formwork, open the galvanized pipe, and the I-beam should have anti-slip measures for fixing the vertical pole;

(3) Install I-beam

When installing the I-beam, pay attention that the upper surface of the I-beam should be on the same level, except that the I-beam should be parallel at the corner, keep both ends horizontal, and the fixing bolts should be tightened;

(4) Set up scaffolding

Set up the first step to control the verticality of the vertical pole and the level of the horizontal pole. Weld a galvanized pipe with a diameter of 30mm at the corresponding position on the upper layer. Pay attention to the position of the upper galvanized pipe to avoid the vertical pole; After the layer pouring is completed and the formwork is removed, the cantilevered tie rods and wall parts are installed in time, and the scaffolding is normally erected and the wall parts, scissors braces, and hanging nets are set up;

The quality control measures for erecting the scaffolding are as follows: use a vertical ruler and a tape measure to control the verticality of the vertical pole and the level of the horizontal pole in the first step of erecting the scaffold body, and the galvanized pipe with a diameter of 30mm welded at the corresponding position on the upper layer, and the same as the lower layer. Method to control the elevation, pay attention to the position of the upper galvanized pipe should avoid the vertical pole, the position can be tested with a wire pipe with the same length as the diagonal rod, and the accuracy of the position, quantity and elevation should be checked after installation;

The outer poles of the scaffolding in the main building are all single poles, and the top of the outer poles on the top floor is 1.8m higher than the structural railings. Except for the top step of the top floor, the joints of the pole joints must be connected by butt fasteners. The rods are connected by right-angle fasteners; the joints are arranged in a staggered manner, and the joints of two adjacent columns are avoided to appear in the same span, and they are staggered by at least 50cm in the height direction; the distance between the center of each joint and the main node is not greater than 1/3 of the step distance; When the pole is lapped at the top, the lap length must not be less than 1m, and it must be fixed by three rotating fasteners at equal intervals, and the distance from the edge of the end fastener cover plate to the end of the lapped longitudinal horizontal pole is not less than 100mm;

The large horizontal bar is placed on the small horizontal bar, and the inner side of the vertical bar is fastened with the vertical bar with right-angle fasteners. The large horizontal bar is connected with butt fasteners, and its joints are arranged in a staggered manner, not in the same span; adjacent joints are horizontal The distance is not less than 50cm, the distance between each joint and the column is not more than 1/3 of the longitudinal distance, and the vertical and horizontal local height difference of the large horizontal bar in the same step frame is not more than 5cm;

A small horizontal bar must be installed at the intersection of each vertical bar and the large horizontal bar, and fastened under the large horizontal bar with right-angle fasteners. The axis of the bar should not deviate from the main node by more than 15cm; The distance is the same, and according to the needs of scaffolding on the working floor, a small crossbar is set at an equal distance between the two columns, and the maximum distance is no more than 75cm; The inner row of large horizontal bars is 15cm away from the outer edge of the structure; the small horizontal bars on the upper and lower floors are arranged staggered at the vertical bars, and the adjacent small horizontal bars on the same floor are arranged opposite to each other at the vertical bars;

The vertical sweeping rod is fixed on the column 20cm above the base with right-angle fasteners, and the horizontal sweeping rod is fixed on the column immediately below the vertical sweeping rod with right-angle fasteners;

The combination of scissors braces and horizontal diagonal braces is adopted, and they are erected synchronously with the columns, vertical and horizontal horizontal bars, and the scissors braces are arranged continuously along the height of the frame. The included angle between the braces and the ground should be controlled between 45° and 60°; the intersection points of the scissors braces should be on the same straight line, and they should be arranged continuously along the height of the frame. The other one is fastened on the protruding end of the small horizontal bar, and the two ends are respectively fixed with rotating fasteners, and 2 to 4 buckle nodes are added in the middle, and the distance between all fixed points and the main node is not more than 15cm, and the bottom end The bottom of the scissors stay should extend to the backing plate;

In addition to setting horizontal braces at each corner, set one every 6 spans in the middle. The horizontal diagonal braces are arranged continuously in a zigzag shape from the bottom to the top layer in the same section. The diagonal rods are made of uniform length rods, which are fixed on the extending ends of the intersecting vertical rods or horizontal horizontal rods with rotating fasteners. After the upper concrete reaches the strength, remove the formwork, first remove the parts that need to install the diagonal stays, and then install the diagonal stays immediately;

The scaffolding on the working floor is made of steel fence, 1m in length and 0.8m in width. The steel fence scaffolding should be laid according to the direction of its main steel bar perpendicular to the longitudinal horizontal bar, and it should be butted and tiled. The four corners should be fixed with No. 16 galvanized iron wire. On the longitudinal horizontal bar, the scaffolding boards of the working layer should be fully paved and paved stably; the scaffolding boards should be laid on the part of the construction operation layer close to the wall, and the scaffolding boards should not be more than 15cm away from the wall. Stretch out the shelving point horizontally by 10-20cm, and should overlap and shelve, and use lead wire to tie the scaffolding board and the shelving point firmly at the place where there is no overlap;

The wall parts are rigidly connected, with a vertical spacing of 3.60m and a horizontal spacing of 3m. The wall connecting piece is connected with the small horizontal bar with pre-embedded galvanized steel flat iron 50mm*5mm, and the connection with the scaffolding adopts right-angle fasteners; the wall connecting piece is as close as possible to the main node, and the deviation from the main node is not more than 300mm;

The tethers are evenly distributed along the edge of the net; the distance between two adjacent tethers is not greater than 0.75m; the length is not less than 0.8m; Form a double pivot. The poles must be firmly supported on the wall or on the floor, and the distance between them should not be greater than 4m. The angle between the poles and the ground should be 45°. Each pole should be equipped with a pull rope, and the upper end of each pole should be equipped with a horizontal connecting rod; The outer opening of the net should be fastened to the large horizontal bar by the side rope, the outer opening should be higher than the inner opening by more than 600mm, the inner opening should be fastened to the railing or building set in the window, and the inner opening of the net should not be more than 150mm away from the wall ; The net and the net should be firmly connected without leaving any gaps. The corners of the net must be firmly erected and tied tightly; it is strictly forbidden to install vertical poles or horizontal poles under the flat net; any debris falling on the safety net should be disposed of in time; the building height is greater than 50m, and a double-layer first-floor flat with a distance of 1.3-1.8m should be installed. Net, the bottom net is 20-20.5m away from the ground, and the extension width from the outer wall is not less than 6m;

For the scaffolding, a vertical pole is added to the inner and outer vertical poles on both sides of the door opening and the entrance and exit, and it is 2 steps higher than the opening. The intersections of the oblique rods and the main nodes are fixed with rotating fasteners; two horizontal supports are added above the opening, and the ends of the oblique web rods should be extended to ensure the integrity of the suspended parts of the columns; two oblique webs are added on both sides of the door opening Rod, and fixed on the protruding end of the small horizontal bar intersected with the rotating fastener, the distance from the centerline of the rotating fastener to the main node is within 15cm; when the diagonal rod spans two steps in one span, A small cross bar should be added at the intersecting large cross bar, and the diagonal web bar should be fixed on its extended end; the diagonal web bar should be a long bar, and the length should be connected with butt fasteners;

The lightning rod is used as a lightning rod on the top of the scaffolding pole. It is made of φ12 galvanized round steel, 1.5 meters long, and the resistance is less than 4 ohms. It is welded to the top of the scaffolding. The length of the double-sided welding is 720. All the uppermost horizontal bars of the scaffolding are connected to form a lightning protection net. , The erected scaffolding shall be sprayed with corresponding color paint as required;

(5) Acceptance and monitoring

After the scaffolding is erected on each floor, it is necessary to inspect and accept the frame body, check the erection of standpipes and horizontal pipes, the arrangement of scissors braces, and wall parts, and check the safety protection, rust prevention, and lightning protection facilities. It is safe and stable, meets the requirements of construction and use, and avoids the occurrence of settlement and collapse accidents exceeding the specification requirements. It is necessary to carry out effective settlement observation of the frame body, and timely adjust and reinforce it;

(6) Remove the scaffolding

Scaffolding and dismantling personnel should be removed in order, and even the wall parts should be removed after all other detachable rods are removed.

As an optimization: the quality control measures for the lower scaffolding are as follows: calculate the length required for erecting the poles at the lower part in advance, so as to avoid the poles being too long; According to the elevation on the pole, the height of the elevation should be the bottom elevation of the I-beam. The junction of the uppermost horizontal bar and the vertical bar can be reinforced with double fasteners to prevent the longitudinal horizontal bar from sliding down after the I-beam is placed.

As an optimization: the above-mentioned pre-embedded quality control measures for this layer are as follows: pre-embedded galvanized casings for this layer, in strict accordance with the requirements of the technical disclosure, carry out accurate construction and laying out, mark with paint, and then use a 20 cm long The 8mm diameter steel bar first welds the two casings, and then seals the two ends of the casing with a sealing tape to prevent the concrete from blocking the casing during the pouring process. Note that the external beams, columns, and slab walls should be closed after the reinforcement panels are tied. Before molding, use a tape measure to measure the elevation of the casing at each part where the I-beam is installed. The welder will weld the casing firmly according to the position and elevation. After all the casings are welded, check the location, quantity, and elevation of the casing again. Whether it is accurate, the carpenter can be notified to close the mold after confirming that it is correct.

As an optimization: before installing the I-beam, weld a steel bar with a diameter of 20mm at a distance of 100mm from the end of the I-beam and at the inner vertical pole. The length of 100 is used to fix the pole. The distance between the two steel bars should be Measure with a tape measure, weld the standpipe on the longitudinal axis of the I-beam to ensure the uniform force of the I-beam, the welded steel bar should be perpendicular to the upper surface of the I-beam, and finally do anti-rust treatment on the welded part.

As an optimization: the quality control measures for installing the I-beam are as follows: place one end of the I-beam on the longitudinal horizontal bar of the bottom scaffold, align the other end with the position of the embedded casing, connect the bolts to the I-beam, and People work together to use a ruler to ensure the level and torsion of both ends of the I-beam, and tighten it with a special wrench. After each group is tightened, retest with a wrench.

As an optimization: the control measures for the acceptance process are as follows: after the scaffolding is erected, check and accept the scaffolding, and the acceptance shall be jointly carried out by the project leader, the deputy person in charge of safety, and the foreman of the scaffolding; the scaffolding shall be checked and accepted in stages ;Each floor should be checked and accepted and the acceptance card should be hanged; in case of five or six strong winds and heavy rains, it must be checked and accepted; it must be checked and accepted after it has been out of use for more than one month; a written record of acceptance must be signed by all parties.

As an optimization: the control measures for the monitoring process are as follows: focus on monitoring the settlement bending of the I-steel support of the cantilever frame and the horizontal displacement of the frame body. The monitoring plan is to arrange 10 monitoring points for each building, with a distance of about 15m. 1 inspection point, one point must be set at each end corner;

The monitoring zero point must be set according to the outer frame monitoring plan before the frame is erected, and special surveyors are arranged to protect and monitor the monitoring points. During the loading process, pay attention to and record the sinking data at any time according to the number of layers; when there is a sudden change in the sinking trend, Monitoring should be strengthened, and if necessary, the project technical director and frame designer should be notified, and the loading should be stopped. After analyzing the cause of the sinking, effective strengthening measures should be taken before loading can be resumed;

Monitoring frequency: start monitoring when the first cantilever section is erected to the height of the cantilevered top, and then monitor twice a month during the construction process. When it is found that the monitoring deformation value is large and close to the warning value, the monitoring frequency should be increased .

As an optimization: the control measures for the demolition of scaffolding are as follows: the demolition operation should be carried out according to the determined procedure: safety net→foot guard and scaffold board→protective railing→scissor brace→diagonal brace→small crossbar→large crossbar→ Vertical poles; it is not allowed to dismantle the façade separately or at the same time in two steps up and down, so that one step can be cleared, and one pole can be cleared;

When dismantling the pole, first hold the pole and then disassemble the last two fasteners. When dismantling the large horizontal bar, diagonal brace, and scissors brace, first remove the middle fastener, then hold the middle, and then unfasten the end fasteners , all connecting wall rods must be lowered synchronously with the removal of the scaffolding. It is strictly forbidden to remove the entire layer or several layers of the connecting wall parts before dismantling the scaffolding. The height difference of segmented removal should not exceed two steps. Reinforcement of wall parts; the stability of the frame body will not be damaged after removal. If the attached wall poles are removed, temporary supports should be added to prevent deformation. When removing each standard section, instability should be prevented; when the scaffolding is removed to the last When the height of the long steel pipe is adjusted, temporary throwing braces should be erected at appropriate positions for reinforcement, and then the wall parts should be removed;

During the dismantling process, all loosely connected rods and accessories should be dismantled and transported away in time to avoid mishandling and leaning; It is not allowed to attach fasteners to the rods or send two rods connected to the ground; all scaffolding boards should be from the outside to the inside. Carry it upright to prevent scaffolding, garbage and other sundries from falling from a high place and hurt people; the dismantled spare parts should be put into the container and hung down with a hanging basket; the dismantled steel pipes should be tied firmly and lifted from two points throw;

When all the dismantled rods are transported to the ground, they shall be cleaned, inspected, repaired and maintained in time, and then piled up at any time according to specifications and varieties for storage. Stop dismantling scaffolding construction when the wind is above level six.

Beneficial effects: the cantilevered scaffolding of the present invention solves the problem of too high erection height of the scaffolding, and is also beneficial to the waterproof construction of the roof of the surrounding garages, road paving and progress control of supporting projects.

With the pull-up external scaffolding scheme, the 12-story steel pipes in the lower part can be removed after the construction of the external wall is completed, which reduces the steel pipe rental fee for the project department.

Except for the reserved holes on the outer walls at the corners, the other outer walls only have reserved holes for bolts, which greatly reduces the processing time and cost of the reserved openings on the outer walls, and reduces the probability of water seepage on the outer walls of the overhanging layer. The pull-up type shortens the length of the I-beam and saves steel. It is fixed with bolts, no I-beam is placed on the floor, and the construction of the secondary structure of the overhanging floor and the pouring of the floor are not affected by the exposed I-beam.

Compared with the scaffolding on the ground, the cantilever scaffolding solves the problem of insufficient space around the building, and does not need to consider the hardening of the erection site.

Compared with the traditional cantilevering method, the pull-up cantilevered scaffolding of the present invention has the characteristics of short construction period, saving steel materials, high safety factor, good anti-seepage of outer walls, and the like. The pull-up cantilevered scaffolding successfully applied in construction can not only improve the safety performance of construction, but also speed up the turnover of materials, thereby reducing construction costs, reducing safety risks, and achieving objective economic benefits.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention, so that those skilled in the art can better understand the advantages and features of the present invention, so as to define the protection scope of the present invention more clearly. The embodiments described in the present invention are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without creative work For example, all belong to the protection scope of the present invention.

Example

The present invention has carried out detailed analysis and research on the quality control of the raw materials of the pull-up scaffold, the detailed treatment of the lower-fall scaffold, the pre-embedding of the casing, the installation of the I-beam, the erection of the scaffold body, acceptance, and dismantling. In summing up the practice of nodes in the construction process.

1. Overview of the embodiment

1.1 Construction preparation

The construction personnel are in place and work with certificates; 16 I-beams, flower baskets, 20 tie rods, 20 bolts and other materials that meet the national standard enter the site; technology and safety measures are in place, and the site is ready for installation.

2. Key points of construction technology

2.1 Materials

Material quality is the foundation of project quality and the key to ensure project construction quality.

2.2 Lower scaffolding

Control the height of the floor stand pole at the bottom of the cantilevered scaffolding on the first floor and the height of the horizontal pole at the top.

2.3 Embedded in this layer

Before the outer formwork of the cantilevered floor beams and columns are closed, the construction set-out line determines the position of each I-beam and makes a mark. Then arrange the master workers to weld the pre-prepared galvanized pipes with a diameter of 300mm to the beams and columns. 2 at each place, used as fixing bolt holes for I-beams. Holes are left in the lighting well with walls on both sides, and the I-beam can be directly penetrated. There is no need to set up the tie rods.

2.4 pole anti-slip

After pouring the overhanging concrete, remove the formwork. Open the galvanized pipe, and the I-beam should have anti-skid measures for fixing the pole.

2.5 Install I-beam

When installing the I-beam, pay attention that the upper surface of the I-beam should be on the same level, except that the I-beam at the corner should be parallel, and the two ends should be kept horizontal. The fixing bolts should be tightened.

2.6 Set up scaffolding

Set up the first step to control the verticality of the vertical pole and the level of the horizontal pole. Weld a galvanized pipe with a diameter of 30mm at the corresponding position on the upper layer. Note that the position of the galvanized pipe on the upper layer should avoid the vertical pole. After the upper layer is poured and the formwork is removed, the cantilevered tie rods and wall parts should be installed in time. The scaffolding is erected normally and the wall parts, scissors braces, nets, etc. are set up.

2.7 Acceptance and monitoring

After the scaffolding is erected on each floor, it is necessary to inspect and accept the frame body, check the erection of standpipes and horizontal pipes, the arrangement of scissors braces, and wall parts, and check safety protection, rust prevention, and lightning protection facilities. In order to ensure the safety and stability of the frame, meet the requirements of construction and use, and avoid the occurrence of settlement and collapse accidents that exceed the specifications, it is necessary to observe the effective settlement of the frame and adjust and reinforce it in time.

2.8 Removal of scaffolding

Scaffold erection and dismantling personnel must be professional scaffolders who have passed the examination and hold a certificate to work. The dismantling should be dismantled in order, especially the connecting wall parts should be dismantled after all other detachable rods are dismantled.

3. Construction quality control measures

3.1 Material quality control measures

Scientific control of materials. It is necessary to start from the source and do a good job in material quality assurance. First of all, in the material purchase and supply contract, it is agreed to adopt the material quality certificate system, and the agreed unqualified materials will be cleared out within a time limit and economic penalties will be imposed. Secondly, hire honest, upright, dedicated, dedicated, mission-oriented and responsible personnel to be responsible for material procurement. Formulate strict engineering material procurement and inspection procedures, strengthen material inspection and acceptance, and strictly control the quality of materials.

3.2 Quality control measures for lower scaffolding

Calculate in advance the length needed to erect the poles in the lower part so that the poles are not too long. When erecting the uppermost vertical horizontal pole, first use a spirit level to photograph the elevation on the vertical poles with a spacing of no more than 10 meters. The height of this level should be the bottom level of the I-beam. The junction of the uppermost horizontal bar and the vertical bar can be reinforced with double fasteners to prevent the longitudinal horizontal bar from sliding down after the I-beam is placed.

3.3 Pre-embedded quality control measures in this layer

The pre-embedded galvanized casing on this layer shall be accurately laid out by the construction technicians of the project department in strict accordance with the requirements of the technical disclosure, and marked with paint. Then use 20 centimeters of long diameter 8mm steel bars to weld the two casings earlier. Then seal both ends of the casing with sealing tape to prevent concrete from blocking the casing during pouring. Note that after the outer beams, columns, and slab walls are tied, use a tape measure to measure the elevation of the casing at each position where the I-beam is installed before closing the outer mold. The welder will weld the casing firmly according to the position and elevation, etc. After all the casings are welded, check again whether the location, quantity and elevation of the casings are accurate. Only after confirming that it is correct can the carpenter be notified to close the mold.

3.4 Pole anti-skid quality control measures

Before installing the I-beam, weld a steel bar with a diameter of 20mm at a distance of 100mm from the end of the I-beam and at the inner vertical pole, and the length is 100mm for fixing the vertical pole. Pay attention to the firmness of the welding. The distance between the two steel bars should be measured with a tape measure, and the standpipe should be welded on the longitudinal axis of the I-beam to ensure the uniform force of the I-beam. The welded reinforcement should be guaranteed to be perpendicular to the upper surface of the I-beam. Finally, do anti-rust treatment on the welding part.

3.5 Quality control measures for installing I-beams

Place one end of the I-beam on the longitudinal horizontal bar of the bottom scaffold, align the other end with the position of the embedded casing, connect the bolts to the I-beam, and use a ruler to ensure the level of the two ends of the I-beam and torsion . And tighten it with a special wrench. After each group is tightened, retest with a wrench.

3.6 Quality control measures for scaffold erection

To set up the first step, use a vertical ruler and tape measure to control the verticality of the vertical pole and the level of the horizontal pole. The galvanized pipe with a diameter of 30mm welded at the corresponding position on the upper layer controls the elevation in the same way as the lower layer. Note that the position of the galvanized pipe on the upper layer should avoid the vertical pole. After the installation is completed, the accuracy of the position, quantity and elevation should be checked.

The outer poles of the main building scaffolding are all single poles, and the top of the outer poles on the top floor is 1.8m higher than the structural railings. Except for the top step of the top floor, the joints of the vertical pole joints must be connected by butt fasteners, and the vertical poles and large horizontal poles shall be connected by right-angle fasteners. The joints are arranged in a staggered manner, and two adjacent column joints are avoided to appear in the synchronous span, and they are staggered at least 50cm in the height direction; the distance between the center of each joint and the main node is not greater than 1/3 of the step distance. When the vertical pole is lapped at the top, the lap length must not be less than 1m, and it must be fixed by three rotating fasteners at equal intervals. The distance from the edge of the end fastener cover plate to the lapped longitudinal horizontal pole end is not less than 100mm.

The large crossbar is placed on the small crossbar, and the inner side of the vertical pole is fastened with the vertical pole with a right-angle fastener. The large horizontal bar is connected by butt fasteners, and its joints are arranged in a staggered manner, not in the same span; the horizontal distance between adjacent joints is not less than 50cm, and the distance between each joint and the column is not greater than 1/3 of the longitudinal distance (this project is not greater than 50cm), The vertical horizontal local height difference of the large crossbar in the same step frame shall not exceed 5cm.

A small horizontal bar must be installed at the intersection (main node) of each vertical bar and a large horizontal bar, and fastened under the large horizontal bar with right-angle fasteners. The axis of the bar should not deviate from the main node by more than 15cm. The spacing between the small horizontal bars is the same as the longitudinal distance of the vertical bars, and according to the needs of erecting the scaffolding boards on the working floor, a small horizontal bar is set at an equal distance between the two columns, and the maximum spacing does not exceed 75cm. The distance between the small horizontal bars extending out from the edge of the large horizontal bars in the outer row is not less than 10cm, and the distance from the large horizontal bars in the inner row is 15cm from the outer edge of the structure. The small horizontal bars on the upper and lower floors are arranged staggered at the vertical poles, and the adjacent small horizontal bars on the same floor are arranged opposite to each other at the vertical poles.

The vertical sweeping rod is fixed on the column 20cm above the base with right-angle fasteners, and the horizontal sweeping rod is fixed on the column immediately below the vertical sweeping rod with right-angle fasteners.

This project adopts the combination of scissors bracing and horizontal diagonal bracing, which are erected synchronously with the columns, vertical and horizontal horizontal bars, and are arranged continuously along the height of the frame with scissors bracing of uniform length. The width of each scissors bracing shall not be less than 4 spans, and shall not be less than 6m , The angle between the scissors brace and the ground should be controlled between 45° and 60°. The intersecting points of the scissors' diagonal bars should be on the same straight line and arranged continuously along the height of the frame. One of the scissors' diagonal bars is buckled on the vertical bar, and the other is buckled on the protruding end of the small horizontal bar. Fix them with rotating fasteners respectively, and add 2 to 4 buckle nodes in the middle. All fixed points are no more than 15cm away from the main node. The bottom of the lowermost scissors support should extend to the backing plate.

In this project, in addition to setting horizontal diagonal braces at each corner, one is set every 6 spans in the middle. The horizontal diagonal braces are arranged continuously in a zigzag shape from the bottom to the top layer in the same section. The diagonal rods are made of uniform length rods, which are fixed on the extending ends of the intersecting vertical rods or horizontal horizontal rods with rotating fasteners. After the upper concrete reaches the strength, remove the formwork, first remove the part where the diagonal tie rods need to be installed, and then install the diagonal stay rods immediately.

Scaffold boards on the working floor are made of steel fence sheets (length 1m×width 0.8m). The steel fence scaffold boards should be laid according to the direction of the main steel bar perpendicular to the longitudinal horizontal bar, and should be butted and tiled. The four corners should be fixed with No. 16 galvanized iron wire On the longitudinal horizontal poles, the scaffolding boards of the working layer shall be fully paved and firmly paved. Scaffold boards should be laid on the part of the construction operation layer close to the wall. The distance between the scaffold boards and the wall should not be greater than 15cm. Use lead wire to fasten the scaffolding to the resting point.

The wall parts are rigidly connected, with a vertical spacing of 3.60m and a horizontal spacing of 3m. The wall parts are connected with the small horizontal bar with pre-embedded galvanized steel flat iron 50mm*5mm, and the connection with the scaffolding adopts right-angle fasteners. The wall connecting parts shall be as close as possible to the main node, and the deviation from the main node shall not be greater than 300mm.

The tethers are evenly distributed along the edge of the net; the distance between two adjacent tethers is not greater than 0.75m; the length is not less than 0.8m; Form a double pivot. The poles must be firmly supported on the wall or on the floor, and the distance between them should not be greater than 4m. The angle between the poles and the ground should be 45°. Each pole should be equipped with a pull rope, and the upper end of each pole should be equipped with a horizontal connecting rod; The outer opening of the net should be fastened to the large horizontal bar by the side rope, the outer opening should be higher than the inner opening by more than 600mm, the inner opening should be fastened to the railing or building set in the window, and the inner opening of the net should not be more than 150mm away from the wall ; The net and the net should be firmly connected without leaving any gaps. The corners of the net must be set up firmly and tied tightly; it is strictly forbidden to set up poles or horizontal bars under the flat net; any debris falling on the safety net should be disposed of in time. The building height of this project is greater than 50m, and a double-layer first-floor flat screen with a distance of 1.3-1.8m should be installed.

For the scaffolding, a vertical pole is added to the inner and outer vertical poles on both sides of the door opening and the entrance and exit, and it is 2 steps higher than the opening. The intersections of the oblique rods and each main node are fixed with rotating fasteners. Two horizontal supports are added above the opening, and the end of the diagonal rod should be extended to ensure the integrity of the suspended part of the column. Add two diagonal rods on both sides of the doorway, and fix them on the protruding end of the small cross bar that intersects with the rotating fastener. The distance from the centerline of the rotating fastener to the main node is within 15cm. When the diagonal rod spans two steps in one span, a small horizontal rod should be added at the intersecting large horizontal rod to fix the diagonal rod on its extended end. The oblique web rod adopts the long rod, and the extension adopts the butt fastener.

The lightning rod is used as a lightning rod on the top of the scaffolding pole, using φ12 galvanized round steel, 1.5 meters long, and the required resistance is less than 4 ohms. Welded with the top of the scaffolding, the length of double-sided welding is 720. Connect all the large horizontal bars on the uppermost layer of the scaffold to form a lightning protection net. The erected scaffolding shall be sprayed with corresponding color paint as required.

3.7 Scaffold acceptance and monitoring process control measures

3.7.1 Acceptance process control measures

After the scaffolding is erected, check and accept the scaffold. The acceptance shall be jointly carried out by the project leader, the deputy person in charge of safety, and the scaffold foreman. Scaffolding should be checked and accepted in stages; each floor should be checked and accepted and the acceptance card should be hanged; in case of strong winds and heavy rains of level 5 or 6, acceptance should be carried out; acceptance should be carried out if it has been stopped for more than one month; written records should be formed for acceptance. Signed by all parties.

3.7.2 Monitoring process control measures

Focus on monitoring the settlement bending of the I-beam support of the cantilever frame and the horizontal displacement of the frame body. In the monitoring plan, 10 monitoring points are arranged for each building, and one inspection point is set at a distance of about 15m, and one point must be set at each end corner.

The monitoring zero point must be set according to the outer frame monitoring plan before the frame is erected, and special surveyors are arranged to protect and monitor the monitoring points. During the loading process, pay attention to and record the sinking data according to the number of layers. When there is a sudden trend of subsidence, monitoring should be strengthened, and if necessary, the project technical director and frame designer should be notified, and loading should be stopped. After analyzing the cause of subsidence, effective strengthening measures should be taken before reloading.

Monitoring frequency: start monitoring when the first cantilever section is erected to the height of the cantilevered top, and then monitor twice a month during the construction process. When it is found that the monitoring deformation value is large and close to the warning value, the monitoring frequency should be increased .

3.8 Control measures for the removal of scaffolding

Before the scaffold is dismantled, it is necessary to comprehensively check whether the fastener connection and support system of the scaffold meet the structural requirements. According to the inspection results, the demolition sequence and measures in this design should be supplemented and improved. It can only be implemented after being reviewed by the project department and approved by the company. The person in charge of the shelf project will conduct a safety inspection before dismantling and make a technical disclosure. When dismantling the frame and leaving get off work every day, hidden danger parts should not be left. When dismantling the scaffolding, it is strictly forbidden to collide with the power line near the scaffolding to prevent electric shock accidents. The dismantling operation should be carried out according to the determined procedure: safety net→foot guard and scaffolding board→protective railing→scissor brace→diagonal brace→small crossbar→large crossbar→vertical pole. It is not allowed to dismantle the facade separately or dismantle it in two steps up and down at the same time, so that one step can be cleared and one pole can be cleared.

When removing the pole, hold the pole first and then disassemble the last two fasteners. When removing large crossbars, diagonal braces, and scissors braces, the middle fasteners should be removed first, then the middle fasteners should be supported, and then the end fasteners should be unfastened. All connecting wall poles must be lowered synchronously with the removal of the scaffolding. It is strictly forbidden to remove the entire layer or several layers of the connecting wall parts before removing the scaffolding. The height difference of segmented removal should not exceed two steps. parts reinforcement. The stability of the frame body will not be damaged after dismantling. For example, before the wall-attached pole is removed, temporary supports should be added to prevent deformation. When removing each standard section, instability should be prevented. When the scaffolding is dismantled to the height of the last long steel pipe in the lower part, temporary throwing braces should be erected at appropriate positions for reinforcement, and then the wall parts should be removed.

During the dismantling process, all loosely connected rods and accessories should be dismantled and transported away in time to avoid misuse and leaning. It is strictly forbidden to throw the dismantled rods and accessories downwards, and they should be hoisted to the ground. At the same time, coordination should be done. It is forbidden for one person to carry out dangerous operations such as dismantling heavy rods. All rods and fasteners are separated when they are removed, and it is not allowed to attach fasteners to the rods or send the two rods to the ground. All scaffolding boards should be carried upright from the outside to the inside to prevent scaffolding boards, garbage and other debris from falling from a high place and hurting people. The dismantled spare parts should be put into the container and hung down with a hanging basket; the dismantled steel pipes should be bound firmly and lifted at two points, and throwing from high altitude is strictly prohibited.

When all the dismantled rods are transported to the ground, they shall be cleaned, inspected, repaired and maintained in time, and then piled up at any time according to specifications and varieties for storage. Stop dismantling scaffolding construction when the wind is above level six (including level six). 4. Problems solved in actual construction

The cantilevered scaffolding solves the problem of too high scaffolding height, and is also conducive to the waterproof construction of the roof of the surrounding garages, road paving and progress control of supporting projects.

With the pull-up external scaffolding scheme, the 12-story steel pipes in the lower part can be removed after the construction of the external wall is completed, which reduces the steel pipe rental fee for the project department.

Except for the reserved holes on the outer walls at the corners, the other outer walls only have reserved holes for bolts, which greatly reduces the processing time and cost of the reserved openings on the outer walls, and reduces the probability of water seepage on the outer walls of the overhanging layer. The pull-up type shortens the length of the I-beam and saves steel. It is fixed with bolts, no I-beam is placed on the floor, and the construction of the secondary structure of the overhanging floor and the pouring of the floor are not affected by the exposed I-beam.

Compared with the scaffolding on the ground, the cantilever scaffolding solves the problem of insufficient space around the building, and does not need to consider the hardening of the erection site.

Compared with the traditional cantilevering method, the pull-up cantilevered scaffolding of the present invention has the characteristics of short construction period, saving steel materials, high safety factor, good anti-seepage of outer walls, and the like. The pull-up cantilevered scaffolding successfully applied in construction can not only improve the safety performance of construction, but also speed up the turnover of materials, thereby reducing construction costs, reducing safety risks, and achieving objective economic benefits.

Claims (8)

1. a kind of construction method of novel pull-up builder's jack, characterized by the following steps:

(1) this layer it is pre-buried

Before overhang layer beam, the molding of column position outboard template, the construction line-putting determines the position of each I-steel, and does easy to remember Number, then master worker is arranged to weld preprepared diameter 300mm galvanized pipe and beam column.2, every place, is used as I-steel There is the light shaft box out of wall on fixing bolt hole, two sides, and I-steel is formed directly into, no setting is required pull rod；

(2) upright bar is anti-skidding

After pouring overhanging layer concrete, form removal gets through galvanized pipe, should there is the non-skid feature of fixed upright bar on I-steel；

(3) I-steel is installed

Installation I-steel notices that the upper surface of I-steel should be in same level, and except corner I-steel should be parallel, both ends are protected Water holding is flat, and fixing bolt should be tightened；

(4) scaffold is set up

The verticality that first step frame body controls upright bar is set up, the level of horizon bar welds one directly upper one layer corresponding position The galvanized pipe of diameter 30mm notices that upright bar is avoided in the position of upper layer galvanized pipe；After having poured demoulding to upper one layer, installation is outstanding in time The pull rod and wall-connecting piece chosen, scaffold are normally set up and are arranged wall-connecting piece, bridging, choose net；

Described to set up scaffold quality control method as follows: setting up first step frame body miter square, tape measure controls hanging down for upright bar The level of straight degree, horizon bar, the galvanized pipe for the diameter 30mm that upper one layer corresponding position is welded, with underlying method elevation control, Notice that the position of upper layer galvanized pipe should avoid upright bar, position is available to be tested with the comparable conduit of oblique pull pole length, is installed Position, quantity, the accuracy of absolute altitude should be checked after finishing；

Main building scaffold outer vertical rod is all using single upright bar, and rod end is higher by structure railing 1.8m, upright bar connector on the outside of top layer In addition to the step of top layer top, remaining each layer is respectively walked connector and must be connected using sleeve couple, and upright bar and leger are connected using right-angle coupler It connects；Connector interlaced arrangement, two adjacent columns connectors, which avoid the occurrence of, to be synchronized with across interior, and is at least staggered in short transverse 50cm；Distance of each connector center away from host node is not more than the 1/3 of step pitch；When top overlaps, the lap of splice must not be small for upright bar In 1m, it is necessary to which equidistant 3 rotary buckles are fixed, and the distance of end fastener side edge thereof to overlap joint longitudinal horizontal rod rod end is not small In 100mm；

Leger is placed on small cross bar, the inside of upright bar, is fastened with right-angle coupler and upright bar, and leger is connected using sleeve couple It connects, connector interlaced arrangement is not being synchronized with across interior；Adjacent connector horizontal distance is not less than 50cm, and each connector is away from column distance No more than the 1/3 of advance, leger vertical equity part height difference in same step frame is no more than 5cm；

Each upright bar and leger intersection all must be provided with a small cross bar, and using right-angle coupler fastening under leger, The rod axis deviates host node and is not greater than 15cm；Small cross bar spacing is identical as upright bar advance, and is taken according to work layer scaffold board If needs, be equidistantly positioned 1 small cross bar between two columns, maximum spacing is no more than 75cm；It is big that small cross bar stretches out outlet Rail edge distance is not less than 10cm, and leger distance structure outer edge 15cm is arranged in stretching；The small cross bar of upper and lower level is at upright bar It is staggeredly arranged, the adjacent small cross bar of same layer is arranged in opposite directions at upright bar；

Bar of longitudinally sweeping the floor is fixed on the column apart from the upward 20cm of pedestal using right-angle coupler, and bar of laterally sweeping the floor is then with right angle button Part is fixed on the column below longitudinal bar of sweeping the floor；

Using bridging in such a way that lateral diagonal brace combines, with column, vertically and horizontally horizon bar is synchronized and is set up, with long bridging of uniting Along the high continuous arrangement of frame, per pass bridging width cannot be less than 4 across, and no less than 6m, the angle of bridging brace and ground It should control between 45 °~60 °；Bridging brace crosspoint should be on same straight line, and along the high continuous arrangement of frame, scissors A piece brace of support is buckled in upright bar, and another is buckled on the end that small cross bar stretches out, and both ends are fixed with rotary buckle respectively, Increase by 2~4 button nodes among it, all fixed points are not more than 15cm, the bottom of the lowermost bridging away from host node distance It reaches at backing plate；

Except in addition to lateral diagonal brace is arranged in each corner, centre is every 6 across one of setting.Lateral diagonal brace is in same internode, the bottom of by To top layer in continuous arrangement in a zigzag, brace is fixed on intersecting therewith upright bar or cross using rotary buckle using system long pole To on the extension end of horizon bar.After upper layer concrete reaches intensity, demoulding is carried out, first removes the portion for needing to install brace Position carries out the installation of brace immediately after；

Work layer scaffold board uses steel basketry piece, long 1m × wide 0.8m, and steel basketry scaffold board should be transversely to the machine direction level by its main reinforcement Bar direction is laid with, and using docking tiling, four angles are fixed in longitudinal horizontal rod using No. 16 galvanized wires, work layer steel Basketry scaffold board should be paved with, spread surely；Constructing operation layer should be laid with scaffold board by metope position, and scaffold board is not greater than from metope 15cm, scaffold board is along long to laying, and end, which should be stretched out, shelves the stupefied 10~20cm of a cross, and should be overlapped and shelve, without overlapping Scaffold board is a little tied with shelving using galvanized wire；

Wall-connecting piece is using rigid connection, vertical interval 3.60m, horizontal space 3m.The pre-buried zinc-plated rigid band iron of wall-connecting piece 50mm*5mm is connect with small cross bar, and the connection with scaffold uses right-angle coupler；Wall-connecting piece deviates master as close as possible to host node Node is not more than 300mm；

Tether is uniformly distributed along selvage；Adjacent two tethers spacing is not more than 0.75m；Length is not less than 0.8m；When muscle rope, tether close One in use, tether portion must lengthen, and fasten with side rope, at least form double pivots.Strut must prop up on wall or floor Jail, its spacing are not greater than 4m, and strut and ground angle are preferably 45 °, and every strut should set drawstring together, and each strut upper end should be set Waling stripe；The outside of safety net mouthful should be tied by side rope and leger, and collar extension should be higher by internal orifice 600mm or more, and internal orifice should be with The railing or building being arranged in window tie, and the internal orifice of net is not greater than 150mm from metope；Net should be connected firmly with net, no It must interspace.The rotation angle position of net must take jail, tighten；Forbid that upright bar or cross bar is arranged under plain net；Safety net has fallen sundries and has answered Processing in time；Building height is greater than 50m, the double-deck first floor plain net at a distance of 1.3-1.8m should be arranged, underlying network is away from ground 20- 20.5m, the stretching width away from exterior wall are no less than 6m；

Scaffold adds a upright bar respectively inside and outside row's upright bar of door opening, entrance two sides, and is higher than 2 step of hole, stands Bar is connected each other with short tube diagonal brace, increases a brace, brace and each host node intersection turn buckle at the hanging upright bar in top Part is fixed；Twice cross-brace is added above hole, the end of diagonal web member should be stretched out, to guarantee globality that column is vacantly located； Door opening two sides increase separately two diagonal web members, and are fixed on the extension end of intersecting therewith small cross bar with rotary buckle, rotation Fastener center line to host node distance within 15cm；When diagonal web member one across it is interior across two step pitches when, should be in intersection A small cross bar is added at leger, and diagonal web member is fixed on its extension end；Diagonal web member use system long pole, spreading use pair Clasp；

Lightning rod makees lightning rod on scaffold upright rod top, 1.5 meters long using 12 galvanized steel bar of φ, resistance less than 4 ohm, with Scaffold top layer leger is all turned on by the welding of scaffold top, two-sided welding length 720, is formed lightning conduction, is set up Scaffold spray the paint of corresponding color as requested；

(5) it checks and accepts and monitors

After scaffold is set up and finished at every layer, frame body is checked and checked and accepted, check standpipe, the setting up of transverse tube, scissors It supports, the arrangement of wall-connecting piece, checks security protection, antirust, lightening protection installation, for the safety and firmness for guaranteeing frame body, meet construction usage Occur it is required that avoiding occurring sedimentation and cave-in accident beyond code requirement, effective settlement observation must be carried out to frame body, in time into Row adjustment is reinforced；

(6) scaffold is removed

Scaffold is taken the personnel of tearing open and should be removed in sequence, and wall-connecting piece should can just be torn open after all other removable rod piece is all removed It removes.

2. the construction method of novel pull-up builder's jack according to claim 1, it is characterised in that: the lower part Scaffold quality control method is as follows: length needed for upright bar is set up in lower part is calculated in advance, in case upright bar is too long, and it is most upper setting up When layer longitudinal horizontal rod, upper absolute altitude is first shone in upright bar of the spacing no more than 10 meters with level meter, the height of the absolute altitude should be work The available double fasteners of the elevation of bottom of word steel, top layer's horizon bar and upright bar intersection are reinforced, to prevent longitudinal after placing I-steel Horizon bar glides.

3. the construction method of novel pull-up builder's jack according to claim 1, it is characterised in that: this described layer Pre-buried quality control method is as follows: this layer of pre-buried zinc-plated casing, in strict accordance with the requirement confided a technological secret, carries out accurately construction and puts Line is marked with paint, is then first welded two casings with 20 centimeters long of diameter 8mm reinforcing bar, then with sealing tape by casing Both ends are shut, and block casing to prevent concrete in casting process, pay attention to closing outer after perimeter beams, column, board wall reinforced slab are pricked The absolute altitude of casing is measured at the position of each installation I-steel with tape measure before mould, and electric welder is according to position and absolute altitude by Socket welding Connect and securely wait that the welding of all casings finishes and then whether the secondary position for checking casing, quantity, absolute altitude accurate, confirm it is errorless after Carpenter could be notified to mold.

4. the construction method of novel pull-up builder's jack according to claim 1, it is characterised in that: in installation I-shaped Before steel, first in the reinforcing bar for the diameter 20mm that burn-ons at the 100mm of I-steel end and at interior survey upright bar, long 100 for fixing Upright bar is used, and standpipe is welded in the longitudinal central axis line of I-steel by the distance tape measure of two reinforcing bars, guarantees I-steel Uniform stressed, the reinforcing bar of welding should ensure that the upper surface perpendicular to I-steel, finally does antirust treatment in welding position.

5. the construction method of novel pull-up builder's jack according to claim 1, it is characterised in that: the installation I-steel quality control method is as follows: I-steel one end being placed in the scaffold longitudinal horizontal rod of bottom, other end alignment is pre-buried Bolt is connect by the position where casing with I-steel, the level and torsion that more people pull together with guiding ruler guarantee I-steel both ends, and It is tightened, every group of fastening and then is reviewed with spanner with special spanner.

6. the construction method of novel pull-up builder's jack according to claim 1, it is characterised in that: the examination Process control measures are as follows: after scaffold building, shelf is checked and is checked and accepted, when examination by project leader, Safe secondary responsible person, shelf section chief etc. carry out jointly；Scaffold should carry out an acceptance inspection stage by stage；Often setting up one layer of object for appreciation will carry out an acceptance inspection And hang acceptance(check) board；It to carry out an acceptance inspection after meeting five, six grades of strong wind and heavy rain；Deactivating will carry out an acceptance inspection more than one month； Examination forms clerking, signs and confirms through each side.

7. the construction method of novel pull-up builder's jack according to claim 1, it is characterised in that: the monitoring Process control measures are as follows: the horizontal displacement for settling flexing and frame body to the I-shaped bracing members of suspension scaffold carries out emphasis monitoring, prison Survey scheme arranges 10 monitoring points by every building, and 1 checkpoint is arranged in about 15m spacing, and each vertex angle part must be provided with a point；

Monitoring zero point must be set according to outrigger monitoring scheme before frame body is set up, and surveyor special messenger is arranged to be responsible for protecting Monitoring point simultaneously monitors, and pays attention in loading procedure by the number of plies at any time and records sinking data；When sinking has mutation trend, Ying Jiaqiang Monitoring notifies Project Technical responsible person and frame body designer when necessary, and stops loading, and after analyzing sunken plaza, has taken It can be reloaded after effect strengthening measure；

Monitoring frequency: when first overhang section set up to this top mark that breaks it is high when start to monitor, it is every in later work progress Month monitored twice, when discovery Deformation Monitoring numerical value it is larger close to early warning value when, Ying Jia great monitoring frequency.

8. the construction method of novel pull-up builder's jack according to claim 1, it is characterised in that: the dismounting The control measure of scaffold are as follows: removing operation should be removed by determining program: safety net → foot guard plate and scaffold board → Guard rail → bridging → hound → small cross bar → leger → upright bar；Inaccurate discrete faces remove or upper and lower two step simultaneously It removes, accomplishes that a step one is clear, a bar one is clear；

It when tearing upright bar open, first to embrace upright bar and dismantle most latter two fastener again, when removing leger, diagonal brace, bridging, should first tear open Between fastener, then hold centre, then solve end fastener, all wall connecting rods must remove synchronous decline with scaffold, first will forbid Scaffold is torn open again after wall-connecting piece flood or several layers of dismounting, and height difference is removed in segmentation should not exceed two steps, as height difference is greater than two steps, Ying Zeng If wall-connecting piece is reinforced；The stability for removing back frame body is not destroyed, and before being removed such as wall attaching rod, Ying Jiashe temporary support prevents from becoming Shape when removing each standard knot, should prevent unstability；It, should be first suitable when scaffold is torn open to the height of last root long steel pipe of lower part Interim throw is taken when position and supports reinforcing, removes wall-connecting piece afterwards；

In demolishing process, all bars for unclamping connection, accessory should be removed in time and be transported, and avoided accidentally helping, accidentally be leaned on；The bar of dismounting is matched Part forbids downward throwing, should be hung to ground, while carrying out matching coordinative work, one is forbidden to carry out removing the danger such as heavier rod piece Property operation；All rod pieces and fastener are separated when removing, and are not allowed to adhere to fastener on rod piece or two bars are ined succession and sent to ground；It is all Scaffold board, should be carried from outer erect inwards, to prevent the sundries such as scaffold board, rubbish from hurting sb.'s feelings from high falling；Zero removed matches Part will be packed into container, be hung down with hanging basket；It is firm that the steel pipe removed will be bound, and two point lifting is forbidden from high-altitude throwing；

After rod piece under removing all is transported to ground, cleaning in time, inspection, trimming and maintenance, then at any time by specification, kind Pile up storage in heaps.Stop removing scaffold construction when more than strong breeze.