First, the construction preparation
1. Technical preparation
(1)) Be familiar with and check the technical data such as construction drawings, structural drawings, specifications and atlas.
(2) Conduct safety technical disclosure to the team according to the drawings and operating process standards, and specify the installation sequence of steel binding:
L) steel sample, processing; 2) Acceptance of reinforcement; 3) steel binding tools; 4) Operating points of steel bar binding; 5) Prevention and treatment of common quality defects in steel bar binding.
2. Material preparation
(1) Formed steel bar: It must conform to the specifications, size, shape and quantity of the ingredient list, and shall conform to the specifications.
(2) Steel wire: galvanized steel wire can be used. The cutting length of steel wire should meet the use requirements.
(3) Cushion block: Fine stone concrete with the same strength as the structure, 50mm square and the same thickness as the protective layer. No.20 ~ No.22 fire wires are reserved in the cushion block, or plastic clips, lacing bars and support rods are used.
3. Preparation of main machines and tools
Steel hook, crowbar, wrench, binding frame, wire brush, trolley, chalk, ruler, etc.
4. Fuck oak parts
(1) After the reinforcement comes into play, check whether there is a factory certificate and a second-round exam report, and pile it with stow-wood according to the location specified in the construction layout, specifications, use parts and numbers.
(2) Do a good job of copying and setting out, play the horizontal elevation lines, and cover the walls, columns and beams with dimension line.
(3) According to the played skin dimension line, check the position, quantity and length of the lower reserved lap reinforcement. If it does not meet the requirements, it should be handled. Before binding, straighten out the overlapping ribs stretched out from the lower layer, and clean up the dirt such as rust and cement mortar.
(4) According to the elevation, check whether the elevation of the concrete surface (column top and wall top) where the lower layer extends out of the overlapping reinforcement meets the requirements of the drawings. If there is any looseness or falsehood, it should be removed and cleaned up.
Second, the quality points
1. Key quality requirements
(1) Before steel bar binding, check whether there is corrosion, and transport it to the binding site after rust removal.
(2) Be familiar with the drawings, and check whether the specifications, shapes and quantities of processed steel bars are correct according to the design requirements.
(3) Do a good job of copying and laying out, and check the position, quantity and length of the reserved lap steel bars at the lower level according to the played skin lines. Before binding, straighten out the overlapping ribs stretched out from the lower layer, and clean up the dirt such as rust and cement mortar.
2. Key requirements of occupational health and safety
(1) When binding steel bars, it is required to wear and use personal protective equipment correctly. Especially for aerial work, you should fasten your seat belt and wear a safety helmet.
(2) When working high above the ground, hand-held tools such as steel bar hooks, crowbars and wrenches should be prevented from being lost and hurting people.
(3) Carefully check the safety, reliability and applicability of high stools, scaffolding and scaffolding.
Third, the construction technology
1. Foundation raft reinforcement
1. Tie the steel mesh at the lower part of the bottom plate
1) According to the reinforced position line played in the waterproof protective layer, the longitudinal reinforcement of the lower mesh shall be laid first, and the reinforced joints shall be welded or mechanically connected as far as possible. It is required that the joints shall be staggered by 50% within the same section, and the same reinforced bar shall not have two joints within 35d or 500mm.
2) After laying short-direction steel bars on the lower mesh, the steel bar joints shall be welded or mechanically connected as far as possible, and the joints in the same section shall be staggered by 5 o%, and the joints of the same steel bar shall be reduced as much as possible.
3) Prevention of common quality defects: Due to the complex construction requirements of floor reinforcement, it is necessary to pay attention to the staggered binding joints and welded joints of reinforcement as required.
4) Binding reinforcement: local reinforcement shall be bound in turn according to the drawing design.
2, binding ground beam reinforcement
1) chalk out the stirrup spacing on the lower horizontal main reinforcement of the flat beam. Stirrup and main reinforcement should be vertical, the intersection of stirrup corner and main reinforcement should be bound, and the intersection of main reinforcement and non-corner part of stirrup should be staggered and bound into plum blossom shape. Stirrup joints, that is, where hooks overlap, are staggered and bound along the horizontal steel bars of the beam.
2) After the ground beam is pre-tied on the trough, it will be directly hoisted in place by tower crane according to the beam line that has been drawn. Binding with bottom plate reinforcement is firm.
3. Tie the steel mesh on the upper part of the bottom plate
1) laying the upper iron horse stool: the horse stool is welded with the remaining short materials, and the horse stool is placed in a short direction with a distance of1.2 ~1.5m. ..
2) Tie the upper mesh to reduce the iron: firstly, tie the erection upright post on the horse stool, draw the position line of steel bar on the erection upright post, and place the upper mesh in turn to reduce the iron according to the drawing requirements. Steel joints shall be welded or mechanically connected as far as possible. Joints in the same section shall be staggered by 50%, and joints in the same steel bar shall be reduced as much as possible.
3) Tie the upper mesh and tie it: according to the position lines of steel bars drawn on the upper and lower irons, place the upper steel bars in turn, and the joints of steel bars shall be welded or mechanically connected as far as possible. The joints in the same section shall be staggered by 50%, and the joints of the same steel bar shall be reduced as much as possible.
4) Binding embedded column and wall steel dowel: According to the laid column and wall position line, bind embedded column and wall steel dowel in place and fix them with floor steel bar by spot welding. The seams are required to be staggered by 50%. If there is no design requirement, the length of the board surface shall be removed ≥45d, two stirrups shall be bound by concealed columns, and a horizontal bar shall be bound by the wall.
5) Cushion protection layer: the protection layer under the bottom plate of the cushion block is 35mm, the main reinforcement protection layer of the beam and column is 25mm, the water surface of the external wall is 35mm, and the inner and inner walls of the external wall are 15mm. Protective layer pad spacing is 600mm, plum blossom layout.
6) finished product protection: when binding steel bars, the steel bars cannot directly contact the external wall brick mold, so pay attention to protection and waterproofing. Before steel binding, the waterproof in the guide wall must be protected by slurry throwing, and the waterproof linoleum on the upper part of the guide wall is covered with red machine bricks to prevent the waterproof coiled material from being damaged during steel bar construction.
2. Tie up the post reinforcement
(1) Flowchart:
Set of column stirrups → lap binding vertical stress reinforcement → stirrup binding.
(2) Column stirrups: Calculate the number of stirrups for each column according to the spacing required by the drawings. First, put the stirrups on the overlapping bars protruding from the lower layer, and then tie the column bars. Within the lap length, there should be no less than three buckles, and the buckles should face the center of the column. When the main reinforcement of the column is overlapped with round steel, the corner hook should be 45o with the formwork, and the middle steel hook should be 90o with the formwork.
(3) Lap-binding vertical reinforced bar: After the main reinforcement of column is installed, the lap length and joint area percentage of binding joint should meet the design requirements. If there is no requirement in the design, it shall comply with the provisions in Appendix 1- 1 of this standard.
(4) Stirrup binding:
Draw the stirrup spacing line: draw the stirrup spacing line with chalk on the vertical bar of the column that has been erected.
(5) column stirrup binding:
L) Move the set stirrup upward according to the stirrup position line, tie it from top to bottom, and tie it with buckles.
2) Stirrup and main reinforcement should be vertical, the intersection of stirrup corner and main reinforcement should be bound, and the intersection of main reinforcement and non-corner part of stirrup should be bound into plum blossom.
3) Hooks of stirrups meet the vertical steel bars along the column, which are staggered and bound firmly.
4) In areas with seismic requirements, the stirrup end of the column should be bent into 135o, and the length of the straight part should not be less than 10d(d is the stirrup diameter). When 900 lap joints are used for stirrups, the lap joints shall be welded, and the length of single-sided welded joints shall not be less than 10d.
5) Stirrup spacing at column foot, column top and beam-column junction shall be encrypted according to design requirements. The stirrups at the upper and lower ends of the column should be encrypted, and the length and spacing of stirrups in the encrypted area should meet the requirements of design drawings. If the design requires stirrups to be provided with lacing bars, the lacing bars should be hooked on the stirrups.
6) The protective layer thickness of column rebar should meet the specification requirements. The protective layer thickness of main rebar is 25mm, and the pad should be tied on the protective layer of column vertical rebar, with the spacing of 1000mm (or plastic Kaka is used on the lateral vertical rebar) to ensure the accuracy of the protective layer thickness of main rebar. When the column section size changes, the column should be bent in the plate, and the bending size should meet the design requirements.
3. Rachel shear wall reinforcement
(1) Flowchart:
Binding embedded column reinforcement → binding embedded beam reinforcement → main reinforcement of vertical shear wall → binding horizontal stress reinforcement.
(2) Erect 2-4 main bars: tie the main bars with overlapping bars protruding from the lower layer, draw horizontal bar grading marks on the main bars, tie two horizontal bars at the lower part and chest level for positioning, draw the main bar grading marks on the horizontal bars, then tie the remaining main bars, and finally tie the remaining horizontal bars. Transverse reinforcement should meet the design requirements, either inside or outside the main reinforcement.
(3) Three horizontal bars shall be bound at the lap joint between the main reinforcement and the extended lap joint reinforcement, and the lap length and position shall meet the design requirements. When there is no requirement in the design, it shall conform to the specifications and standards.
(4) Shear wall reinforcement shall be bound point by point, the vertical and horizontal spacing of double-row reinforcement shall not be greater than 600mm, and the reinforcement sheath shall be bound with cushion blocks or plastic cards (ladder reinforcement can also be used to ensure the thickness of reinforcement protective layer).
(5) At the joint of shear wall and frame column, the horizontal bar of shear wall should be anchored in the frame column, and its anchoring length should meet the design requirements. For example, when pouring column concrete first, and then binding shear wall steel bars, connecting steel bars should be reserved in the column or iron pieces should be embedded in the column as the connection when disassembling the column and tied to the wall steel bars. Its reserved length should comply with the provisions of the design or specification.
(6) The anchorage length of horizontal reinforcement of shear wall at both ends, corners, cross joints, coupling beams and the reinforcement around the hole should meet the design seismic requirements.
(7) After clamping, the protruding main reinforcement shall be trimmed, and a transverse reinforcement shall be tied at the lap joint for positioning. When pouring concrete, there should be a special person to take care of it, and then it should be trimmed again to ensure the accurate position of the steel bar.
4. Beam steel binding
(1) Flowchart:
Draw the position line of beam stirrups → put stirrups → pass through the reinforced beam → tie stirrups.
(2) Draw the stirrup spacing on the beam side formwork and place the stirrup.
(3) First, pass through the longitudinal stressed steel bars and bent steel bars at the lower part of the main girder, and separate the stirrups one by one according to the drawn spacing; Wear the longitudinal stressed steel bars and bent steel bars at the lower part of the secondary beam, and set stirrups; Put the scissors of primary and secondary beams; Tie up the installation stud and stirrup at regular intervals; Adjust the spacing of stirrups to meet the design requirements, tie vertical bars, then tie main bars, and coordinate primary and secondary beams at the same time.
(4) The upper longitudinal reinforcement of the frame beam should run through the middle node, and the anchorage length of the lower longitudinal reinforcement of the beam extending into the middle node and the length beyond the center line should meet the design requirements. The anchorage length of longitudinal reinforcement in end nodes of frame beams should also meet the design requirements.
(5) Tie the stirrups of the upper longitudinal bars of the beam with the method of set buckle.
(6) Stirrup hooks at the lap joint in the beam shall be staggered and bound. The stirrup hook is 135o, and the length of the straight part is 10d. If the closed hoop is made, the length of one-sided weld is 5d.
(7) The first stirrup at the beam end should be set 50mm away from the edge of column node. The stirrup at the joint of beam end and column should be encrypted, and its spacing and encryption zone length should meet the design requirements.
(8) Place cushion blocks (or plastic cards) under the stressed steel bars of the main beam and the secondary beam to ensure the thickness of the protective layer. When the stressed steel bars are in double rows, short steel bars can be placed between the two layers of steel bars, and the row spacing of steel bars should meet the design requirements.
(9) Lapping of beam reinforcement: When the diameter of the stressed reinforcement of the beam is equal to or greater than 22mm, welded joints shall be adopted; When it is less than 22mm, a binding joint can be adopted, and the lap length should comply with the regulations. The distance between the end of the lap length and the bend of the steel bar should not be less than 10 times the diameter of the steel bar. The joint should not be located at the maximum bending moment of the member. In the tension zone, the end of the binding joint of FPB235 steel bar should be hooked (HRB335 steel bar can't be hooked), and the lap joint should be fastened at the center and both ends. The positions of the joints should be staggered. When binding lap joints are used, the cross-sectional area of reinforced bar with joints accounts for the percentage of the total cross-sectional area of reinforced bar in any area with specified lap length, and the tensile area is not more than 50%.
5. Steel plate binding
(1) Flowchart:
Draw the position line of main reinforcement and distribution reinforcement on the template → put the main reinforcement first and then the distribution reinforcement → tie the plate reinforcement → pad the protective layer of reinforcement or limit card.
(2) Clean up the sundries on the template, and draw the spacing between the main reinforcement and the distribution reinforcement on the template with chalk.
(3) spacing as planned, put the main reinforcement first, and then put the distribution reinforcement. Embedded parts, electrical conduits and reserved holes shall be installed in time.
(4) When the cast-in-place slab has a slab beam, the slab beam reinforcement shall be bound first, and then the slab reinforcement shall be placed.
(5) When binding plate reinforcement, straight buckle or splayed buckle is generally adopted. Except for the intersection of two peripheral steel bars, other points can be bound alternately (the intersection of two-way slabs should be bound completely). If the floor is a double-layer reinforced bar, a reinforced horse stool should be added between the two layers of reinforced bars to ensure the position of the upper reinforcement. Each intersection of negative moment reinforcement shall be bound.
(6) The mortar pad is placed under the steel bar with the spacing of 1.5m, and the thickness of the pad is equal to the thickness of the protective layer, which should meet the design requirements. If there is no requirement in the design, the thickness of the slab should be 15 mm, and the requirements for the lap length and lap position of reinforcement are the same as those of the above beams.
6. Stair steel binding
(1) Flowchart:
Clean the template → draw lines on the template → tie the reinforced bar under the plate → tie the reinforced bar with negative bending distance.
(2) Draw the position lines of main reinforcement and distribution reinforcement on the stair board.
(3) According to the direction of main reinforcement and distribution reinforcement in the design drawings, tie the main reinforcement first and then the distribution reinforcement, and tie each intersection. If there is a stair beam, tie the beam first, and then tie the slab reinforcement. Plate reinforcement should be anchored in the beam.
(4) After the bottom plate steel bar binding is completed, after the step template is hoisted, the step steel bar is bound. The number and location of main reinforcement joints shall comply with the design and construction quality acceptance specifications.
Fourth, quality standards.
1, master project
(1) The variety and quality of reinforcement must meet the design requirements and relevant standards.
(2) the steel surface must be clean. After derusting, it is forbidden to use the reinforcement with granular or flaky old rust and pockmarks according to the original specifications. Steel surface should be kept clean.
(3) The specification, shape, size, quantity, anchorage length and joint position of reinforcement must meet the design requirements and construction specifications.
(4) The results of mechanical properties of welded or mechanically connected joints of steel bars must conform to the special provisions for acceptance of welded and mechanically connected steel bars.
2. General items
(1) The number of missing buttons and loose buttons shall not exceed 10% of the number of tied buttons, and shall not be concentrated.
(2) The hook is oriented correctly, the binding joint conforms to the provisions of the construction specification, and the lap length is not less than the specified value.
(3) The spacing of stirrups should meet the design requirements. When the seismic requirements are met, the hook angle is 1350, and the straight line length of the hook is 10d.
(4) When binding reinforcement, it is forbidden to touch the embedded parts and the template of the hole.
(5) The allowable deviation items conform to the specifications.
3, finished product protection
(1) After the column reinforcement is bound, it is not allowed to be trampled.
(2) After the bent steel bar of the floor is tied with the negative bending moment steel bar, it is not allowed to walk on it. When pouring concrete, assign a steel reinforcement worker to repair it, so as to ensure the correctness of the negative bending moment steel bar position.
(3) Don't pollute the steel bar when applying isolation agent on the inner surface of the steel formwork. ()
(4) When installing electric conduits, heating pipes or other facilities, steel bars shall not be cut and moved at will.
Verb (abbreviation of verb) Safety and environmental protection measures
(1). Strengthen environmental awareness education for operators. The transportation, loading and unloading and processing of steel bars should prevent unnecessary noise to maximize.
Minimize construction noise pollution.
(2) The lifting points of steel bars shall be selected and firmly bound to prevent falling.
(3) After work, waste steel bar heads shall be collected and cleaned in time to keep the site clean.