I. Construction Preparation
Materials
1) Reinforcing Steel φ is Grade 1 steel, φ is Grade 2 steel, φ is Grade 3 steel. Various specifications,
various levels of rebar. There must be product certification, factory inspection report, field re-inspection report.
2) The wire used for rebar binding is 20#~22# galvanized iron wire.
3) The protective layer mat is made of 1:2 cement mortar 50*50mm square, and its strength should meet the requirements.
2. Mechanical preparation
Steel cold-drawing machine, straightening machine, cutting machine, bending machine, bending machine, spot welding machine, butt welding machine, arc welding machine and the corresponding lifting equipment.
Operating conditions
1) First familiarize yourself with the relevant drawings to determine the order of installation and tying.
2) all kinds of equipment in the operation and maintenance intact, to ensure normal operation and comply with safety regulations.
3) steel processing and production before, should be based on the project construction drawings and related design changes in accordance with the specification of different
components to make the ingredient list < steel specifications, shape, size, quantity >. Calculate the amount of rebar, as the basis for steel processing.
II. Operation process
1. The surface of the steel bar should be clean, and the adhering oil, soil, floating rust must be cleaned up before use. With granular or flaky old rust after descaling still have pockmarked steel bar is prohibited from use in accordance with the original provisions.
2. Before the formal processing of rebar, the subcontractor needs to report to the general contractor the rebar ingredient list, and can only be processed after the approval of the general contractor.
3. Steel cutting should be based on the number, diameter, length, size and quantity of steel. Long and short collocation, first cut off the long material and then cut off the short material, minimize and shorten the short head of the rebar, in order to reduce the loss of steel. No rebar head of more than 1m is allowed.
4. The bending diameter of the middle part of the steel bend up at the bend is not less than 5 times the diameter of the steel bar, the end of the hoop bar should be made of the bending hook, the bending diameter of the bending hook should be larger than the diameter of the stressed steel bar and not less than 2.5 times the diameter of the hoop bar; the length of the straight part of the bending hook should not be less than 10 times the diameter of the hoop bar for the seismic requirements, and the bending angle of the bending hook should be 135 degrees.
5. Allowable deviation of steel processing. (Note: processed according to the negative deviation)
Item Allowable deviation (㎜)
The net size of the full length of the force reinforcement along the length direction ±10
The bending position of the bent reinforcement ±20
The net size of the hoop reinforcement inside ±5
6. Reinforcing bar wire processing
①Process
Technical process
The steel reinforcement end surface flatten head → stripping rib rolling Threading → head quality inspection → cap protection → head quality sampling → stored for use
② operation points
The rebar end face flat head: the use of wheel cutting machine flat head (strictly prohibit gas cutting), to ensure that the end face of the rebar and the parent material axis direction perpendicular.
Stripping and rolling thread: use the steel stripping and rolling straight threading machine to process the end of the steel bar to be connected into a thread.
Tap quality inspection: quality inspection of the processed tap.
Flattening of reinforcement bar end: adopt wheel cutting machine to flatten the end (gas cutting is strictly prohibited) to ensure that the end face of the reinforcement bar is perpendicular to the direction of the axis of the parent material.
Stripping and rolling thread: use the steel stripping and rolling straight threading machine to process the end of the steel bar to be connected into a thread.
Protection with cap: use special plastic protection cap for rebar thread to prevent the thread from being bumped or contaminated by dirt.
Sampling of wire head quality: the project quality department will carry out sampling inspection on the self-inspection qualified wire head.
Storage for use: according to the specifications of the type of machine for classification and yardage.
7. beam and plate reinforcement binding and installation
Beam reinforcement binding: when the height of the beam is small, the beam reinforcement overhead in the top of the beam binding, and then drop; when the height of the beam is large, the beam reinforcement is suitable for the beam bottom mold directly binding, and its two sides or one side of the template after the installation.
Slab reinforcement binding: clean up the template → template on the drawing line → binding plate under the force tendons → binding negative moment reinforcement.
The protective layer of the floor is a net protective layer, and the stress reinforcement is underneath and the distribution reinforcement is on top.
1) The scaffolding for tying beam reinforcement is the same as the scaffolding for tying wall reinforcement.
2) The upper bending hook of beam and plate reinforcement is facing down, and the lower bending hook is over the top. At the intersection of slab, secondary beam and main beam, the slab reinforcement is at the top, secondary beam reinforcement is at the middle level, and main beam reinforcement is at the bottom. The same hoop joints are staggered on the two longitudinal stiffeners. When the longitudinal stress tendons are multi-layer, short steel pads are used between layers to ensure their spacing.
3) beam longitudinal force reinforcement: face bar net distance ≥ 30mm or 1.5d (d is the largest diameter in the bar), bottom bar net distance ≥ 25mm or d; lower longitudinal reinforcement configuration ≥ two layers, the horizontal distance of the steel bar is doubled than the distance of the following two layers.
4) The lower reinforcement of the beam is not connected within 1/3 of the span, and the upper reinforcement is not connected within 1/3 of the support.
5) Reinforcing bars in the slab are configured from 50mm from the edge of the wall or beam.
6) Lower reinforcement of slab is not lapped or connected within 1/3 of span and upper reinforcement is not connected within 1/3 of support.
7) Hoop reinforcement: 50mm from the wall or beam edge configuration, hoop spacing and number of details see the construction drawings.
8) reinforcement binding and installation should also meet the drawings, the relevant specification requirements.
9) in the floor has been supported on the base plate template, according to the design drawings of the specifications of the spacing on the position of the rebar line, and before the line will be cleaned up the grass-roots level, will be cleaned up on the reinforcing steel attachments, rebar tying requirements for the first tying of the main reinforcement, and then tied after the distribution of tendons, each intersection must be tied, do not allow leakage and lack of tying.
10) After the bottom bar is tied, tie the bench, and before the bench and the negative moment tendon is tied, pad the protective layer and then tie the surface bar.
11) When pouring concrete, avoid touching the reinforcement and make sure that the reinforcement is spaced to ensure that the section size is correct.
8. Staircase reinforcement binding
Clean up the grass-roots level → laying the base reinforcement → padding protective layer placing the bench → tying the surface reinforcement and negative moment tendons → report to the inspection → the next process of construction.
9. Straight thread mechanical connection
1) process
steel in place → unscrewing the protective cap of the steel bar → joint tightening → marking → construction inspection
2) operation
① steel bar in place: the head of the inspection of the steel bar (wire fastening is clean and undamaged) to the place where the connection is to be made. ② joint tightening: joint connection with a torque wrench for construction. Tighten the two reinforcing bars in the middle of the sleeve, and the tightening torque of the joint should be in accordance with the provisions of the table. The precision of torque wrench is ±5%.
Rebar diameter (mm) 25
Tightening torque (N-m) 250
③ Marking: The tightened rolled straight-threaded joints should be marked to distinguish them from the untightened joints. The length of the exposed wire buckle on one side is not more than two buckles.
4 Construction inspection: the quality inspection of the joints after construction.
10. Column reinforcement
Set up column reinforcement support scaffolding → set of column bars → connect and tie the vertical force tendons → draw the hoop spacing line → tie the hoops
① Set up column reinforcement support scaffolding: column reinforcement support frame scaffolding steel pipe, the operating surface around the paving of the springboard, and hang the safety net.
② set column hoop: according to the drawings required spacing, calculate the number of hoops for each column, the first set of hoops in the lower level of the outstretched steel, and then tie the positioning steel, standing column reinforcement. ③ Mechanical connection of vertical stress tendons: after the column reinforcement is erected, the mechanical connection joints, sleeve size should be in accordance with the design and relevant specification requirements.
④ Drawing hoop spacing line: on the vertical reinforcement of the column erected, draw the hoop spacing line with chalk according to the requirements of the drawings.
⑤ Column hoop binding, connection: hoop joints (bend superposition) should be staggered in the four corners of the longitudinal reinforcement, column corner reinforcement and hoop with double buckle staggered binding, binding buckle should be made between each other in a figure of eight.
The hoop bar and the main bar should be perpendicular.
6 The vertical reinforcement of the lower column is exposed to the floor, and it is fixed by the column hoop.
⑦ When there is a change in column section, the exposed part of the lower column reinforcement is contracted accurately before tying the upper beam.
⑧ column header reinforcement processing see 03G101 and structural design of the general instructions.
9 column protective layer thickness should be consistent with the design and specification requirements.
11. Column positioning bars
Column positioning bars are set up in two ways, the first one is set at 50mm above the top of the lower concrete column, and the second one is set at 50mm from the top of the column. After tying is completed, the first locating bar is not taken out, and the second locating bar can be recycled after cleaning.
14. Reinforcing steel protective layer
1) The thickness of the protective layer of the concrete base plate is equal to the thickness of the protective layer, and it is placed in the shape of plum blossom every 0.8m.
2) column concrete protective layer stuck in the column corners of the outer skin of the vertical bars, set every 0.8m interval.
3) beam concrete protective layer every interval of 0.8m set up one, each set of 6 pieces (including both sides).
4) slab concrete protective layer pad thickness is equal to the thickness of the protective layer, every 0.8m plum blossom-shaped placement.
5) plate reinforcement support, horse stool placed between the two layers of steel mesh.
Safety measures
1. Construction personnel must be technically trained, and hold the induction operation.
2. Wire head processing should be water-soluble cutting fluid, it is strictly prohibited to use machine oil cutting or processing without cutting fluid.
3. Equipment must be connected to the ground, equipment power supply must have leakage protection device, equipment maintenance must be specialized personnel, not private maintenance.
4. All operations and related equipment must be in line with the appropriate safety norms, regulations, standards. 5. Machinery installation must be solid and stable, to maintain the level of placement, welding machinery must be placed in the rain
and well-ventilated places, welding site is not allowed to pile up flammable and explosive materials.
6. Construction machinery must be set up to protect the device, each machine must be a machine a gate and set leakage protection switch.
7. The workplace to keep the road clear, dangerous parts must be set up obvious signs, the operator must be familiar with the performance of machinery and operating procedures.
8. Carrying rebar, pay attention to the front and rear direction there is no danger of collision or hooked material, pay attention to the feet, to prevent the probe of the head of the rebar mixing down or stabbing, especially to avoid hanging around and up and down the direction of the wire, manual handling of rebar, unloading to pay attention to the safety.
9. In the rebar forest place, thunderstorms are not allowed to operate and stand people.
10. In the high-altitude tying or welding operation must have operating frame, operating frame must be laid on the springboard, tied to the protective railing and skirting board. When it is difficult to set up a protective frame operators must hang a good safety belt.
11. The team leader of the team's work area is responsible for the civilization of the site. Adhere to who builds, who cleans up, to do the work of the site clear, must be cleaned up before the end of the day.
12. Small tools, appliances shall not be littered, after use in a timely manner to the warehouse for safekeeping. Receiving personnel to clean up the welding slag in a timely manner.
13. The welding slag will be cleaned up in a timely manner.
14. Steel will be placed on the scaffolding, edge, hole, the use of leftover steel to timely clear
management, lifting away, binding wire is not littered. 15. All types of steel semi-finished products stacked neatly.