Frame structure forming combined steel formwork

This technical disclosure is applicable to the installation and removal of steel formwork of cast-in-place frame shear wall structure in industrial and civil buildings.

1. Material and equipment requirements

(1) shaped steel formwork: the length is 600, 750, 900, 1200, 1500mm, and the width is 100, 150, 200, 250, 300mm.

(2) Angle die of section steel: Yin-Yang angle die and connecting angle die.

(3) Connectors: U-shaped clips, L-shaped bolts, type 3 fasteners, disc fasteners, opposite bolts and fastening bolts.

(4) Fixture: column hoop, special-shaped hollow steel stare blankly, steel pipe strut, steel diagonal brace, steel truss, beam bracket, wood, etc.

(5) Steel formwork and fittings shall meet the quality standards after repair.

(6) Isolation agent: mainly used waste engine oil.

2. Main machines and tools

Axe, saw, wrench, drilling electric drill, wire hammer, ruler board, square ruler, molten iron level, crowbar, etc.

3. Fuck oak parts

(1) formwork design: according to the structural type and characteristics of this project and the site construction conditions, determine the formwork plane layout, the specifications, quantity and arrangement size of longitudinal and transverse keels, the type and spacing of column hoops, the beam-slab support spacing, the formwork assembly form (on-site assembly or prefabricated assembly) and the detailed structure of connecting nodes. Check the strength, rigidity and stability of formwork and support. Draw a complete set of template design drawings (template plan, block drawing, assembly drawing, node detail drawing, part processing drawing). When designing templates, the number of templates should be divided according to the flow section, and a comprehensive study should be made to determine the reasonable number of templates.

(2) Precast assembly:

1) The assembly site shall be tamped and leveled, and an assembly operation platform shall be set if possible.

2) Assemble according to the template design. Each hole of two adjacent plates is clamped with a U-shaped clamp, and the keel is clamped with the rib hole on the edge of the plate with a hook bolt.

3) When assembling the column and shear wall formwork, the cleaning port or grouting port shall be reserved.

(3) After the template is assembled, it shall be numbered, coated with release agent and stacked in different specifications.

(4) Put away the axis, template sideline and level control elevation. The bottom of the template should be leveled with cement mortar. Check and correct whether the ground anchor of the column is embedded.

(5) Column and wall reinforcement assembling is completed, water and electricity pipelines and embedded parts have been installed, reinforcement protection pads have been tied, and hidden inspection procedures have been completed.

4. Operation process

(1) column formwork installation:

Process flow:

Elastic column positioning line → positioning pier screeding → column template installation → column hoop installation → tie rod or brace installation → preview.

1) Apply cement mortar screed-coat according to the elevation, locate pier column according to the position line, and ensure the accuracy of column axis and elevation, or according to the pay-off position, weld the pillar on the main reinforcement at the four sides of the column 5 ~ 8 cm from the ground, and resist the template from all sides to prevent displacement.

2) Installation of column formwork: arrange columns in rows, install columns at both ends first, and then pull wires to correct the middle column after correction and fixation. According to the size of the column, the formwork will be pre-assembled into a piece (one side will use corner formwork), or both sides of a piece will be tied in place with lead wires and temporarily fixed with the main reinforcement, and the two sides of the formwork will be connected with U-shaped cards, and then the other two sides of the formwork will be installed after installation.

3) Install column hoop; Column hoop can be made of angle steel and steel pipe. When using wooden formwork, steel hoop can be made of bolts and square wood. When designing formwork, column hoop should be determined according to formwork size and lateral pressure.

4) Install the tie rod or brace of the formwork. Each side of the formwork is provided with two tie rods, which are fixed on the reinforcing ring embedded in the floor in advance, controlled by theodolite, and adjusted by flower basket bolts to correct the verticality of the formwork. The angle between the tie rod and the ground should be 45 degrees, and the distance between the embedded steel ring and the column should be 3/4 column height.

5) Clean the mold, close the cleaning port, and carry out mold pre-inspection.

(2) Shear wall formwork installation:

Elastic line → Anmenkong template → Anbian template → Anbian template → adjustment and fixation → preview.

1) Install the door formwork and embedded parts or wooden bricks according to the position line.

2) Put the pre-assembled side formwork in place according to the position line, and then install tie rods or diagonal braces, plastic sleeves and wall bolts. The specifications and spacing of wall bolts should be clearly specified in the formwork design.

3) Clean up the wall debris, install the formwork on the other side, adjust the diagonal brace (tie rod) to make the formwork vertical, and then tighten the wall bolts.

4) After the template installation, check whether the fasteners and bolts are fastened, whether the template flat-fell seam and the lower mouth are tight, and complete the pre-inspection procedures.

(3) Beam formwork installation:

Elastic line → supporting column → adjusting elevation → installing beam bottom formwork → binding beam reinforcement → installing side formwork → doing preview.

1) Column pops up axis and horizontal line on concrete after form removal.

2) Before installing the beam steel column (such as the bottom ground must be compacted), the column should be padded with long scaffolding. Generally, single row is used for beams and columns, and double or multiple rows can be used when the beam section is large. The spacing of columns shall be specified by the template design. In general, the spacing should be 60 ~ 100 cm. Column pad 10× 10 cm square timber, column plus shear brace and horizontal tie rod. Set one 50 cm above the ground, and set one every 2 meters above.

3) Adjust the elevation of the column according to the design elevation, then install the beam bottom plate, and stay straight. The bottom plate of the beam should be arched. When the beam span is equal to or greater than 4m, the bottom plate of the beam should arch according to the design requirements. If there is no requirement in the design, the springing height should be11000 ~ 3/1000.

4) Tie beam reinforcement, conduct concealed inspection after passing the inspection, remove sundries, install side formwork, and connect the side formwork with bottom plate with U-shaped card.

5) Use beam bracket or tripod to support and fix beam side formwork. Keel spacing should be stipulated by the template design, generally 75cm, and the top of the beam template should be fixed with a fixing clip. When the height of the beam exceeds 60 cm, increase the beam bolts for reinforcement.

6) After installation, correct the centerline, elevation and section size of the beam. Clean up the sundries in the beam formwork, and conduct pre-inspection after passing the inspection.

(4) Floor formwork installation:

Ground compaction → supporting column → installing size keel → paving formwork → correcting elevation → adding vertical horizontal tie rod → doing preview.

1) The bottom ground should be compacted and padded with long scaffolding, and the floor ground should also be padded with long scaffolding before being erected. Multi-layer support formwork, columns should be vertical, and the upper and lower columns should be on the same vertical center line.

2) Starting from one side of the side span, install the first row of keels and columns, temporarily fix them on the beam, and then gradually install the second row of keels and columns. The spacing between the column and the keel should be designed according to the template design specification. Generally, the column spacing is 80 ~ 120cm, the large keel spacing is 60 ~ 120cm, and the small keel spacing is 40 ~ 60cm.

3) Adjust the height of the column and level the large keel.

4) Paving and molding of composite steel formwork blocks: paving can be started from one side, the side ribs between every two plates are connected by U-shaped cards, and every two blocks on each side of the U-shaped cards are connected by at least two ways. The clamping direction of each U-shaped card should be opposite, not the same direction. Large-scale shaped composite steel formwork blocks should be used for large-area floor slabs, and narrow-size formwork or wooden boards can be used instead of flat-fell joints, but all flat-fell joints should be tight.

5) After the platform plate is paved, measure the template elevation with a level gauge, and after correction, level it with a guiding rule.

6) After bidding in colleges and universities, horizontal tie rods should be added between columns. According to the height of the column, determine the number of horizontal tie rods. Under normal circumstances, it is 20 ~ 30 cm from the ground, and every 1.6 m in the vertical and horizontal direction should be checked frequently to ensure integrity and firmness.

7) Clean up the sundries in the template and make a preview.

(5) template removal:

Wall, column and beam formwork shall be removed as a whole first, so as to facilitate the overall transfer and repeat the overall installation.

1) Dismantling of column formwork: firstly, dismantle the column diagonal tie rod or support, then dismantle the column hoop, then dismantle the U-shaped clamp connecting the formwork of each column, and then gently pry the formwork with a crowbar to separate the formwork from the concrete.

2) Dismantling the wall formwork: firstly, remove the wall bolts and other accessories, then remove the diagonal tie rod or brace, and gently pry the formwork away from the wall with a crowbar or lift it away.

3) Plate and beam formwork removal:

Dismantle the beam side formwork first, and then dismantle the floor formwork. Dismantle the horizontal tie rod first, and then dismantle the columns, leaving 1 ~ 2 columns for each keel.

B. The operator stands in the gap of demolition, and removes the remaining pillars nearby, so that the keel can fall freely.

C. Hook the formwork with a hook, and after the formwork of this section is completely demoulded, it will be transported out and piled up in a centralized way.

When the D floor is high and the formwork adopts double-layer bent, the upper bent shall be removed first, so that the keel and formwork will fall on the bottom bent, and then the bottom bent shall be removed after all the upper steel formwork is shipped out.

E, if there are any through-wall bolts, dismantle the through-wall bolts and beam supports first, and then dismantle the beam bottom die.

F column template dismantled concrete strength should be able to ensure that its surface and stare blankly Angle is not damaged by dismantling the template, can be removed. When the wall formwork is removed, the concrete strength must exceed 1MPa before it can be removed. When there is no regulation on the template strength of plate and beam, it shall comply with the provisions of construction specifications.

4) Dismantle the formwork, clear the adhesion in time, brush the release agent, and collect and manage the dismantled fasteners in time.

5. Quality standards

(1) guarantee project

Formwork and its supports must have sufficient strength, rigidity and stability; Its supporting part should have sufficient supporting area. If it is installed on foundation soil, the foundation soil must be solid and have drainage measures. Frost heave soil must be protected from freezing and thawing.

(2) Basic projects

The width of formwork joints shall not be greater than1.5mm. The formwork surface shall be cleaned and measures shall be taken to prevent adhesion. The cumulative area of the wall and board with mucilage and template with missing isolation agent shall not exceed 65,438+0,000 square centimeters; Columns and beams should not exceed 400 square centimeters.

(3) Allowable deviation items: See Table 2-37.

Table 2-37 Allowable deviation of template installation and embedded parts and reserved holes

Inspection method of allowable deviation (mm) of the project

Single and multi-storey high-rise frames

Check the axial displacement of columns, walls and beams by 5 3 feet.

Elevation +5+2

-5 Check with a spirit level or a stay wire and a ruler.

Section size of wall, column and beam +4

-5 +2

-5-foot inspection

The verticality of each layer is 3/3, which shall be checked with 2m support plate.

Check the surface height difference between two adjacent plates with a ruler and a ruler.

Check the surface flatness with 2m guide rule and wedge feeler gauge.

The center line displacement of embedded steel plate, embedded pipe and reserved hole is 3/3.

embedded

Displacement of bolt center line 2 2 Check cable and ruler

Exposure length+10

-0 + 10

-0

The displacement of the center line of the reserved hole is 10.

Internal dimension of section+10

-0 -0

6. Finished product protection

(1) When lifting the formwork, handle it with care. No collision is allowed to prevent the formwork from deforming.

(2) Don't pry with a sledgehammer or crowbar when ripping, so as not to damage the concrete surface and stare blankly angle.

(3) If the removed steel formwork is found to be abnormal or the rib is damaged and deformed, it should be repaired in time.

(4) Steel moulds should be well managed, stacked in different specifications and coated with antirust agent in time.

7. Quality problems that should be paid attention to.

The problems of (1) column formwork are: inaccurate section size, too large concrete protective layer and twisted column body. Matters needing attention are as follows: before formwork support, play the position line according to the figure, correct the position of reinforcement, and make a small square template for the front column of the column to ensure the accurate position of the bottom. According to the column section size and height, the column hoop size and spacing are designed, and supports and pull rods are arranged at the four corners of the column.

(2) The beam-slab formwork is prone to problems: the beam body is not straight, the bottom of the beam is uneven, the side of the beam is bulging, the size of the upper mouth of the beam is increased, and the middle part of the plate is skewed. Precautionary measures are as follows: the size and spacing of keel and pillar should be determined in the design of beam-slab formwork, so that the formwork support system has enough strength and rigidity to prevent the formwork from being deformed when pouring concrete. The bottom of the formwork column should be supported on a solid ground, padded with long scaffolding to prevent the column from sinking, and the beam slab formwork should be arched according to the design requirements to prevent excessive deflection. The upper mouth of beam formwork shall be locked by tie rod to prevent deformation of upper mouth.

(3) The common problems of wall formwork are: inconsistent thickness of wall concrete, inaccurate cross-section size, lax splicing and oversize joints, resulting in slurry leakage. Template should be based on the height and thickness of the wall through the design to determine the size and spacing of longitudinal and transverse keel, wall support method, the form of corner template. Rachel should be set at the top of the template to prevent the top size from being too large.