Precast reinforced concrete frame structure components are installed
1 scope
The technology standard is applicable to general industrial and civil buildings multi-layer framework precast beam, column, slab concrete components are installed.
2 construction preparation
2.1 material and main equipments:
2.1.1 artifacts: precast reinforced concrete beam, column, and other components, shall have the factory certificate. Component specification, type, position and quantity, the appearance quality of embedded object, etc., shall comply with the design requirements and the prefabricated concrete component quality inspection evaluation standard "(GBJ321-90).
2.1.2 steel bar and steel: specification, shape should conform to the requirements of the drawings, and shall have the steel factory certificate.
2.1.3 cement: appropriate USES 425, 525 ordinary Portland cement. Columns caulked appropriate USES 525 expansive cement or not less than 525 ordinary Portland cement. Unfavorable use or pozzolana cement slag cement.
2.1.4 stones: particle size 5 ~ 32 mm. , silt content is not more than 2%.
2.1.5 sand, medium sand and coarse sand and silt content is not more than 5%.
2.1.6 electrode: according to the design requirements and the relevant provisions of the welding current range to choose. Neatly packaged, stainless, not should have product certificate and directions for use.
2.1.7 template: according to the construction requirements and specifications needed for preparing is complete, the brush good mold release agent. 100 mm * 100 mm, 100 mm x 50 mm square. 50 mm thick planks.
2.1.8 main machines: hoisting machinery, electric welding machine and related equipment, electrode drying box, wire rope, snap ring, flower basket corrector, lock collar, slip line, pillar support, board hook, theodolite, level, box staff, by foot plate, iron pole, jack, chain hoist, crowbar. Steel rule, etc.
2.2 operation conditions:
2.2.1: familiar with drawings for the design drawings, especially the structure construction drawing, component processing, node structure details, atlas, should carry on the comprehensive understanding of and familiar with. Conscientiously grasp component model, quantity, weight, node approach, the key points of construction operation, safety in production technology, the work high above the relevant provisions and the relationship between various parts, etc.
2.2.2 preparation of lifting scheme, according to the structure of the structural characteristics and construction technology requirements, combined with the actual conditions, making structure hoisting plan carefully. And the construction personnel safety, quality, technical disclosure.
2.2.3 preview main components: according to the structure construction drawing and processing components list, check to artifacts in type, quantity, specification, the strength of concrete, reserve embedded iron pieces, steel dowel location, the number is in line with the design drawings, ever component factory certificate.
2.2.4 flare line: the embedded parts and exposed main reinforcement cement slurry and rust on sundry clean governance. On the artifacts play axis (middle), namely the positioning line installation, indicate the direction, number axis and elevation lines. Pillars shall be three axis of the play. First posts except play axis, but also on three sides with + / - 0.00 mm is horizontal. Good cross the center line of embedded object. The ends of the beam axis play, using axis control installation location.
2.2.5 control floor installation elevation: component link anchor structure parts are completed, put a floor column grid axis line and elevation control line, the good post joint parts of the composite layer from top to bottom, embedded and leveling positioning plate and calibration the elevation. Floor column grid axis, such as clear and accurate.
2.2.6, adjust the upper part of the composite beam exposed steel welding at the ends of the main reinforcement asked directly buried, check the connection parts according to design requirements of main reinforcement length, position. Under the condition of without affecting the normal installation, the flower basket fastened the upper beam of the main steel beam, column head positioning embedded parts can also be welded on the composite beam of steel, but must ensure that its elevation, position accurately.
2.2.7 selected hoisting machinery according to the construction organization design approach, and conform to the safety in production of appraisal of classics commissioning procedures, ready to lifting appliances, before hoisting.
2.2.8 erection of scaffolding, safety protection, in accordance with the provisions of the construction organization design on the lifting job set-up lifting scaffolding and operation platform, and safety protection facilities. And by the relevant personnel to check and acceptance, identification, conform to the safe production regulations, before formal operation. No safety and security measures, work may be undertaken.
2.2.9 to the floor of beams and columns, such as plate component according to the plane position nearby flat. To prevent pillars in reverse when lifting, small head lifting touches the ground cracks or bend the main reinforcement, can adopt safe leg, or set up in the main reinforcement at the end of the place mat wood, to prevent the main reinforcement for lifting bending deformation.
2.2.10 welder should have operation certificate and code, the official shi before welding welding test must be conducted to adjust welding parameters, provide simulation welding parts, after the test pass, accurate operation.
3 operation process
3.1 process:
The column hoisting (correction - positioning and welding) - girder hoisting (correction - main rebar welding) - - > beam-column joint core processing
Shear wall construction - plate installation
3.2 column hoisting:
3.2.1 structure for hoisting, lifting scheme prescribed order generally move forward along the vertical axis direction, step by step a segmented flow operation, each floor from the beginning of the end, to reduce the repeated work, when a horizontal axis line, after the completion of the pillars of the hoisting hanging under the pillars of a horizontal axis line again.
3.2.2 cleanup post installation site of sundry, will loose concrete and embedded steel plate higher positioning dung was removed, check the pillar axis, the position of the locating plate, elevation and anchoring meets the design requirements.
3.2.3 in hoisting pillars and advocate muscle to check out, according to the length will be cut off excess part of design, to ensure the positioning small stigma smoothly is located on the pillars of joint positioning plate. Will lower to straighten out the main rebar, straighten, guarantee with lower columns reinforced lap close leaning close, easy to weld.
3.2.4 lifting pillars: lifting point pillar position and number of lifting point is determined by the column length, cross section shape, the general selection is buckle tie, click on the column from the top of up to 600 mm card good special column hoop, lock the card at the bottom of the column hoop ring steel wire rope, lifting machinery of clasps rope with a snap ring area using stuck on the card, the wire should be lifting point directly above. Slowly lifting, wait for after the rope tight stop rising and timely check automatically snap ring and reliable, to prevent tripping on their own, to control the lifting in place when not back and forth, at the bottom of the pillar slip line hang up, check each connection, right rear can lifting.
3.2.5 pillars in place: when the pillar lift from 500 mm to stop, remove the protective pillar of main reinforcement stow-wood and leg, clean up the stigma of dirt, and then the signalman command, lift the column to the floor is in place. When in place, slow down to the installation position, stop, check the number of pillars, adjust the azimuth, controlled by two people, small stigma all-round anastomosis of positioning is correct, can land on installation location. Pillars checkmark to check the direction of the shear wall plug iron (steel), directional table, then hang around in turn buckle, suspension rope, adding temporary fixed support, to ensure safety.
3.2.6 correction and positioning:
3.2.6.1 pillars verticality calibration: with ceiling plate, and on the two vertical directions in erection of theodolite, make the body elevation axis and installation position of the column grid axis alignment, vertically up and down. Correction axis when look for the good on the surface of the two axis, and then on the third axis, on the surface of the final make axis or center line on the surface of the three pillars on axis positioning. Has in place a good post, carefully use theodolite calibration axis position and verticality, confirmation is not beyond the deviation, may head positioning steel plate welding.
3.2.6.2 column (column) in the installation of correction and positioning: shall prevail, with the center line of the pillar bedding face in place after all. Respectively with two theodolite in adjacent cylinder axis, alignment scape axis, vertical deviation correction. Observing correction scape axis, to make the high throughout from bottom to top. When two transit from two directions after correction, check the other two on the surface of the axis, all supporting strong, can be small on stigma with positioning steel plate and steel plate welding fixed first, and then welding the main reinforcement, for a second correction.
3.2.6.3 side column, corner post installation, calibration and positioning: edge, Angle with installed only on the 2 ~ 3 square timber, from within the floor taut basket corrector. When installing Angle in addition to the three axes location after correction, but also for the fourth axis on the surface of the check to ensure that the lower pillar in the node does not produce contorted, dislocation and migration.
3.2.7 to take off the hook before the Lord must be reinforced and stigma, spot welding place, prevent due to support the rickety, taut turn buckle clashing with each other and pillars) tip over.
3.2.8 adjustment the main steel, welding: the collision in the process of hoisting steel bar, will advocate muscle straightening before welding, the straightening out, make up the main reinforcement position right, depend on each other tightly, easy to weld. When article for welding is used, should be the same as the level of main reinforcement steel bar; When lap welding is used, should meet the requirements of lap length, consists of two double sided weld. Welds when asked to use two electric welding machine, diagonal, symmetry, constant arc, arc extinguishing basic synchronization. Using the discontinuous welding to prevent uneven thermal effect leads to stress, produce too large, the deformation of the concrete and avoid burns the main reinforcement. Small head positioning plate all sides around the welding. After welding is introspected. Quality conform to the requirement of welding procedures, fill in construction records, indicate the welding symbol. Post advocate muscle after welding, for cooling, the weld shall be removed. At this time to review action: use a theodolite and line review column of verticality, controlled in the range of allowable deviation of less than, observed deviation, available chain for correction, hammer, pry the root must not be used as fierce hit, hard to pry, advocate muscle injury.
Beam hoisting 3.3:
3.3.1 lifting in place: according to the construction plan of the installation sequence and any relevant models, specifications of the beam pattern, the axis of the play ends (or line), straightening out on both ends of reinforced sanity. After hanging pillar in the studio, first crane girder crane beam, again points between buckles floor.
3.3.1.1 lifting: in accordance with the regulations of the drawings or the construction scheme is identified in the lifting point location, hook and rope lock. Pay attention to the wire Angle generally should not be less than 45 ° Angle. Such as using the rings, lifting rope must be tied up at the same time insurance. When using out the lifting, must use card ring card. Hang up after the hook line slowly ascend, taut hook line, 500 mm or so stop rising from the ground, carefully check the sling is firm, fastened on the safe side, before lifting in place. Lifting one or local pick on the edge of the beam, to seriously consider its center of gravity position, avoid eccentric, prevent tilt. Lifting point should be close to rings or beam end parts.
3.3.1.2 in place: to check again before lifting the stigma of fulcrum GangDian elevation, whether conform to the requirements of the installation location, in place when looking for a good axis positioning on stigma and the relationship between the beam axis, so that the beam right in place. The two ends of the beam pillar top application.
3.3.2 rainfall distribution on 10-12 calibration and main reinforcement beam welding, in place after the solid, elevation, pivot position of beam correction. Finishing beam reinforced with corresponding to the head of the main reinforcement after each other tight, easy to welding. In order to control the displacement of the beam should be made on both ends of the beam center line at the bottom of the aim point and the positioning line at the top of the pillars, if the error is not big, can use a crowbar slight touch of alignment; When the error is bigger, pry roots are not allowed to use hard to pry, otherwise it will affect the perpendicularity of the pillars of change. Beam should be to lift, slightly away from the pedestal, operators respectively from two balance, visual alignment axis, left hook to smooth, slowly sit down, and then make the bottom of the beam axis on the axis of the pillars. Liang Shen vertical deviation correction from both ends of thread object is, mutual deviation, again with a crowbar beam bottom pad, use iron mat smooth sealed, until both ends of the vertical deviation are controlled within the scope of the permit, the notice in the process of the whole correction, must at the same time use the theodolite observation posts, as vertical change. As a result of beam installation makes the vertical deviation beyond the allowable value of pillars, must be adjusted again. Elevation and pivot position correction, right when the beam topside is firm, can be welding, welding quality should comply with the requirements.
3.4 beam and column joint core processing:
3.4.1 track beam and column core practices to conform to the requirements of the design drawings and building aseismic structure atlas. By using welding closed hoop reinforcement, the entire area encryption stirrup spacing, diameter, number, 135 °, hook, straight section length, etc., shall meet the design requirements and construction norms. In the feng up part of the composite beam should be set 1 phi 12 position of the closed hoop, used to control the correct position of the pillar advocate muscle and joint.
3.4.2 edge, Angle, sealing needle node: lap anchorage length of beam and column the main steel and weld, must meet the requirements of design drawings and seismic code. Position of beam on the top edge Angle joint reinforced except with beam reinforcement under lap welding, reinforced with pillars embedded anchor reinforcement on the rest of the weld. Pillars anchoring reinforcement should be welded (diagonal Settings.
The strength of the concrete rule 3.4.3 node area level should be higher than that of column concrete strength grade 10 mpa. Column joint caulked with dry concrete (weight ratio 1:1:1 harsh pisolite concrete), appropriate USES pouring cement mixture, control the water cement ratio of 0.3, its strength than to concrete strength increased 10 mpa. Caulking seams to be removed before; With hemp rope, hemp sack filling full moisture; The two sides with template. Two people at the same time symmetry with eccentric chisel operation, and fill with the twist. Construction should be maintained 7 d, prevent shrinkage crack. In the upper structure before installation, should be pillars joint parts are completed.
Node area can also be mixed of UEA shrinkage-compensating concrete, the strength grade should be higher than that of column concrete strength grade 10 mpa, the mixture ratio and casting methods to design department agree.
3.5 plate installation (floor or roof panel) : can use hard frame mode branch or direct method is in place.
3.5.1 track of paddle board line of position: on the basis of design drawing board and board beam side seam line of position, mark plate model.
3.5.2 plate in place: the beam or the wall skin clean, check the elevation, the axis of the review. The required plate lifting in place. Related content can be found in the prestressed round orifice plate installation process standards.
Shear wall construction: 3.6 shall be on the floor of the beam, column, the board after the installation is complete, all with interspersed with vertical steel bar inside the hollow beam, and insert the embedded in the horizontal reinforcement and column iron (steel) welded. Joint position should comply with the norms of construction. According to the construction organization design requirements for a good template, pouring concrete vibratory compaction, strengthen the maintenance.
4 quality standards
4.1 ensure projects:
4.4.1 artifacts when lifting concrete strength, joint (joint) of the lower structure internal force under the concrete or mortar strength, must comply with the design requirements and norms. Check the component factory certificate and test report with condition maintenance test specimen.
4.1.2 component model, location, protection anchor must comply with the design requirements, and no deformation and damage phenomenon. Observe or feet quantity inspection and check the lifting record.
4.1.3 component joint (joint) concrete (mortar) must be accurate measurement, cast close-grained, serious maintenance, its strength must meet the design requirements or construction norms. 28 d block observation to inspection standard and inspection test report and the construction record.
4.2 the basic items:
2 beams, columns, plates in place anchorage: axis location, elevation, sit pulp and node structure practice, plate end plugging holes, plate end anchorage, plate width, should meet the design requirements.
4.2.2 joint welding components, should comply with the design requirements and norms. Main reinforcement and connected to the steel plate welding seam length, width, thickness, shall comply with the design requirements and construction norms. Weld surface smooth, uniform wave welding, no sag, flash, and burns, no cracks, porosity, slag inclusion and joint bite edge. Welding slag, coated and splash is clean.
4.3 allowable deviation projects, see table 4-39.
5 finished product protection
5.1 floor column grid axis to keep well versed in, clear, installation node elevation, please indicate need processing should have clearly marked, shall any daub, change and pollution.
5.2 installation of beam and column location up to guarantee the accuracy of the elevation, shall not be any move, touch attack and shift.
Precast frame member allowable deviation of installation and inspection method table 4-39
Will project allow deviation (mm) check method
1 the center line of the column to position the axis offset 5 'quantity check
2 the center line of the column from top to bottom interface position offset 3 feet, quantity check
3 5 m column 5 or less
Four column vertical degree > 5 m column 10 quantity check with theodolite or messenger wire and ruler
More than 5 > 10 m section column 1 ‰ column high and < 20
6 5 m + 0 or less, to 5 level or feet quantity check
7 > 5 m + 0, 8 -
8 axis displacement deviation of 5 feet, quantity check
9 layer + 0 level or feet high quantity check
10 rebounds to shelve length + 10 feet quantity check
Plaster 5 by feet and feeler check
Don't plaster 3
12 the centerline of axis positioning line 5 'quantity check
13 beam beam surface elevation + 0-5 quantity check with level or messenger wire and ruler
14 vertical deviation 3 quantity check with messenger wire and ruler
15 the stairs horizontal displacement and migration 10 feet quantity check
16 the balcony the + / - 5 level, feet high quantity check
5.3 main reinforcement node shall not be skewed, bending, clean up the rust and may not be so heavily in filthy process. Before concrete pouring node with phi 12 steel welded closed localization band, fixed pillars main reinforcement position. Node stirrup encryption area enclosed welding, the spacing comply with the design and the requirements of the seismic atlas, binding is firm.
5.4 has been installed in the beam, column, the board shall not be arbitrarily will remove, support and pull rod should be can be removed after welding of all the main steel cooling calibration facilities. When installing a beam, should observe the verticality change of pillars, produce deviation should be timely to prevent or correct.
5.5 components during transport and storage, bedding position should comply with the provisions of the chock, generally should be close to the rings, the thickness of the block should be higher than the rings, and skid into a straight line up and down. To prevent unreasonable for bedding, component damage. Stacking area should level off, solid, and may not be water. The underlying application 100 mm x 100 mm square timber or double scaffold board smooth bedding. Each pile shall be stipulated in the construction organization design pattern height packed neatly.
5.6 installation of various pipelines, shall not be arbitrarily pick carved artifacts. Construction shall not be arbitrarily cut steel or bent into a hard bending damage to the finished product.
6 should pay attention to quality problems
6.1 component defects: use error component model, specification. The strength of the component factory has yet to reach regulation, cause fracture or damage. In front of the transportation and installation, check the appearance quality of the components, strength of concrete. The right method of handling and transportation. Damaged or defect components without identification technology department, shall not be used.
Component displacement deviation 6.2: before installation components should indicate the type and use of the site, after review the feeding size for installation, prevent the pay-off component offset error. Different adjustment of measuring error of climate change. Operation is serious and responsible, careful calibration. The component location, elevation, verticality meets the requirements.
6.3 don't correspond to the upper and lower axis, in the wrong, impact component installation: construction steel, the upper positioning line should be from the bottom up, using theodolite perpendicular, determine the correct floor axis. Guarantee, between the lower axis perfectly.
Cast concrete imperfect: 6.4 node template is lax running pulp. Before pouring node template seam wall should be strict. Core steel bar is dense, casting should be vibrating in earnest. Concrete has good workability, appropriate slump. Template to be kept cleaning the mouth, clean up seriously, avoid the slag.
: 6.5 the main reinforcement displacement node location below post main reinforcement displacement, create difficulties to lap welding. Reason is the component production when not take measures to control the main reinforcement position; Component in the process of transportation and hoisting cause deformation of the main reinforcement. So the production should take measures to ensure Liang Zhuzhu reinforcement position correctly, avoid collisions when hoisting, straighten out before installation.
6.6 core structure does not conform to the requirements: because of the large core steel bar, so construction should be carefully at the picture, in accordance with the requirements of the node structure construction. Steel bar connection location accurate, overlapping each other tight, easy to weld. The number of stirrups should conform to the requirements of the drawings.
6.7 high floor: the main is to control the elevation is lax in hoisting process, raise the installation elevation. Should from the first beginning, putright plinth epithelial actual relative elevation, find the elevation of the column bottom leveling layer. Installing a floor pillars, to adjust the positioning plate level to control the elevation of floor, node positioning plate application level leveling, according to the actual situation of pillars, pillars set positioning plate negative deviation. Negative deviation in 3 ~ 5 mm advisable, can use steel plate adjustment.
Scape skewed 6.8: reason is bad welding method. Improvement idea is to beam and column joints, there are two or more than two solder joints, welding methods should be adopted to lose flow. Process of welding is not allowed to fierce pry bar, the main steel welding process using theodolite observation column, vertical deviation correcting in time when problems found.
6.9 displacement of pillars: only when in place in accordance with the small stigma on reticle in place, and not controlled the axis of the fust general; The main steel welding, thermal deformation effect produce distortion, lead to displacement of pillars.
6.10 post vertical super wide, scape: straight when installation, should be on both sides of the adjacent verticality calibration pendant with lines. Small stigma on the connecting plate after welding, reoccupy pillars corrector for secondary rectification. Symmetry is used in the main reinforcement, constant speed, intermittent welds. Reasonable welding sequence arrangement, plum point should be adopted from the framework of the whole stagger welding method, prevent due to the effect of uneven stress during welding, to avoid frame to produce different degree of deformation.
6.11 welding quality does not meet the requirements, should strictly abide by the welding procedures.
7 quality records
This technology standard should have the quality records
7.1 component factory certificate.
7.2 steel factory certificate.
7.3 steel mill certificate and mechanical properties of the second interview report.
7.4 electrode factory certificate.
7.5 welders working certificate.
7.6 the welding test report.
7.7 cement factory certification and retest report.
7.8 sand, stone test report.
7.9 structure lifting record record (preview).
7.10 concrete block strength of 28 d report.
7.11 component installation engineering quality inspection record separately.
1 scope
The technology standard is applicable to general industrial and civil buildings multi-layer framework precast beam, column, slab concrete components are installed.
2 construction preparation
2.1 material and main equipments:
2.1.1 artifacts: precast reinforced concrete beam, column, and other components, shall have the factory certificate. Component specification, type, position and quantity, the appearance quality of embedded object, etc., shall comply with the design requirements and the prefabricated concrete component quality inspection evaluation standard "(GBJ321-90).
2.1.2 steel bar and steel: specification, shape should conform to the requirements of the drawings, and shall have the steel factory certificate.
2.1.3 cement: appropriate USES 425, 525 ordinary Portland cement. Columns caulked appropriate USES 525 expansive cement or not less than 525 ordinary Portland cement. Unfavorable use or pozzolana cement slag cement.
2.1.4 stones: particle size 5 ~ 32 mm. , silt content is not more than 2%.
2.1.5 sand, medium sand and coarse sand and silt content is not more than 5%.
2.1.6 electrode: according to the design requirements and the relevant provisions of the welding current range to choose. Neatly packaged, stainless, not should have product certificate and directions for use.
2.1.7 template: according to the construction requirements and specifications needed for preparing is complete, the brush good mold release agent. 100 mm * 100 mm, 100 mm x 50 mm square. 50 mm thick planks.
2.1.8 main machines: hoisting machinery, electric welding machine and related equipment, electrode drying box, wire rope, snap ring, flower basket corrector, lock collar, slip line, pillar support, board hook, theodolite, level, box staff, by foot plate, iron pole, jack, chain hoist, crowbar. Steel rule, etc.
2.2 operation conditions:
2.2.1: familiar with drawings for the design drawings, especially the structure construction drawing, component processing, node structure details, atlas, should carry on the comprehensive understanding of and familiar with. Conscientiously grasp component model, quantity, weight, node approach, the key points of construction operation, safety in production technology, the work high above the relevant provisions and the relationship between various parts, etc.
2.2.2 preparation of lifting scheme, according to the structure of the structural characteristics and construction technology requirements, combined with the actual conditions, making structure hoisting plan carefully. And the construction personnel safety, quality, technical disclosure.
2.2.3 preview main components: according to the structure construction drawing and processing components list, check to artifacts in type, quantity, specification, the strength of concrete, reserve embedded iron pieces, steel dowel location, the number is in line with the design drawings, ever component factory certificate.
2.2.4 flare line: the embedded parts and exposed main reinforcement cement slurry and rust on sundry clean governance. On the artifacts play axis (middle), namely the positioning line installation, indicate the direction, number axis and elevation lines. Pillars shall be three axis of the play. First posts except play axis, but also on three sides with + / - 0.00 mm is horizontal. Good cross the center line of embedded object. The ends of the beam axis play, using axis control installation location.
2.2.5 control floor installation elevation: component link anchor structure parts are completed, put a floor column grid axis line and elevation control line, the good post joint parts of the composite layer from top to bottom, embedded and leveling positioning plate and calibration the elevation. Floor column grid axis, such as clear and accurate.
2.2.6, adjust the upper part of the composite beam exposed steel welding at the ends of the main reinforcement asked directly buried, check the connection parts according to design requirements of main reinforcement length, position. Under the condition of without affecting the normal installation, the flower basket fastened the upper beam of the main steel beam, column head positioning embedded parts can also be welded on the composite beam of steel, but must ensure that its elevation, position accurately.
2.2.7 selected hoisting machinery according to the construction organization design approach, and conform to the safety in production of appraisal of classics commissioning procedures, ready to lifting appliances, before hoisting.
2.2.8 erection of scaffolding, safety protection, in accordance with the provisions of the construction organization design on the lifting job set-up lifting scaffolding and operation platform, and safety protection facilities. And by the relevant personnel to check and acceptance, identification, conform to the safe production regulations, before formal operation. No safety and security measures, work may be undertaken.
2.2.9 to the floor of beams and columns, such as plate component according to the plane position nearby flat. To prevent pillars in reverse when lifting, small head lifting touches the ground cracks or bend the main reinforcement, can adopt safe leg, or set up in the main reinforcement at the end of the place mat wood, to prevent the main reinforcement for lifting bending deformation.
2.2.10 welder should have operation certificate and code, the official shi before welding welding test must be conducted to adjust welding parameters, provide simulation welding parts, after the test pass, accurate operation.
3 operation process
3.1 process:
The column hoisting (correction - positioning and welding) - girder hoisting (correction - main rebar welding) - - > beam-column joint core processing
Shear wall construction - plate installation
3.2 column hoisting:
3.2.1 structure for hoisting, lifting scheme prescribed order generally move forward along the vertical axis direction, step by step a segmented flow operation, each floor from the beginning of the end, to reduce the repeated work, when a horizontal axis line, after the completion of the pillars of the hoisting hanging under the pillars of a horizontal axis line again.
3.2.2 cleanup post installation site of sundry, will loose concrete and embedded steel plate higher positioning dung was removed, check the pillar axis, the position of the locating plate, elevation and anchoring meets the design requirements.
3.2.3 in hoisting pillars and advocate muscle to check out, according to the length will be cut off excess part of design, to ensure the positioning small stigma smoothly is located on the pillars of joint positioning plate. Will lower to straighten out the main rebar, straighten, guarantee with lower columns reinforced lap close leaning close, easy to weld.
3.2.4 lifting pillars: lifting point pillar position and number of lifting point is determined by the column length, cross section shape, the general selection is buckle tie, click on the column from the top of up to 600 mm card good special column hoop, lock the card at the bottom of the column hoop ring steel wire rope, lifting machinery of clasps rope with a snap ring area using stuck on the card, the wire should be lifting point directly above. Slowly lifting, wait for after the rope tight stop rising and timely check automatically snap ring and reliable, to prevent tripping on their own, to control the lifting in place when not back and forth, at the bottom of the pillar slip line hang up, check each connection, right rear can lifting.
3.2.5 pillars in place: when the pillar lift from 500 mm to stop, remove the protective pillar of main reinforcement stow-wood and leg, clean up the stigma of dirt, and then the signalman command, lift the column to the floor is in place. When in place, slow down to the installation position, stop, check the number of pillars, adjust the azimuth, controlled by two people, small stigma all-round anastomosis of positioning is correct, can land on installation location. Pillars checkmark to check the direction of the shear wall plug iron (steel), directional table, then hang around in turn buckle, suspension rope, adding temporary fixed support, to ensure safety.
3.2.6 correction and positioning:
3.2.6.1 pillars verticality calibration: with ceiling plate, and on the two vertical directions in erection of theodolite, make the body elevation axis and installation position of the column grid axis alignment, vertically up and down. Correction axis when look for the good on the surface of the two axis, and then on the third axis, on the surface of the final make axis or center line on the surface of the three pillars on axis positioning. Has in place a good post, carefully use theodolite calibration axis position and verticality, confirmation is not beyond the deviation, may head positioning steel plate welding.
3.2.6.2 column (column) in the installation of correction and positioning: shall prevail, with the center line of the pillar bedding face in place after all. Respectively with two theodolite in adjacent cylinder axis, alignment scape axis, vertical deviation correction. Observing correction scape axis, to make the high throughout from bottom to top. When two transit from two directions after correction, check the other two on the surface of the axis, all supporting strong, can be small on stigma with positioning steel plate and steel plate welding fixed first, and then welding the main reinforcement, for a second correction.
3.2.6.3 side column, corner post installation, calibration and positioning: edge, Angle with installed only on the 2 ~ 3 square timber, from within the floor taut basket corrector. When installing Angle in addition to the three axes location after correction, but also for the fourth axis on the surface of the check to ensure that the lower pillar in the node does not produce contorted, dislocation and migration.
3.2.7 to take off the hook before the Lord must be reinforced and stigma, spot welding place, prevent due to support the rickety, taut turn buckle clashing with each other and pillars) tip over.
3.2.8 adjustment the main steel, welding: the collision in the process of hoisting steel bar, will advocate muscle straightening before welding, the straightening out, make up the main reinforcement position right, depend on each other tightly, easy to weld. When article for welding is used, should be the same as the level of main reinforcement steel bar; When lap welding is used, should meet the requirements of lap length, consists of two double sided weld. Welds when asked to use two electric welding machine, diagonal, symmetry, constant arc, arc extinguishing basic synchronization. Using the discontinuous welding to prevent uneven thermal effect leads to stress, produce too large, the deformation of the concrete and avoid burns the main reinforcement. Small head positioning plate all sides around the welding. After welding is introspected. Quality conform to the requirement of welding procedures, fill in construction records, indicate the welding symbol. Post advocate muscle after welding, for cooling, the weld shall be removed. At this time to review action: use a theodolite and line review column of verticality, controlled in the range of allowable deviation of less than, observed deviation, available chain for correction, hammer, pry the root must not be used as fierce hit, hard to pry, advocate muscle injury.
Beam hoisting 3.3:
3.3.1 lifting in place: according to the construction plan of the installation sequence and any relevant models, specifications of the beam pattern, the axis of the play ends (or line), straightening out on both ends of reinforced sanity. After hanging pillar in the studio, first crane girder crane beam, again points between buckles floor.
3.3.1.1 lifting: in accordance with the regulations of the drawings or the construction scheme is identified in the lifting point location, hook and rope lock. Pay attention to the wire Angle generally should not be less than 45 ° Angle. Such as using the rings, lifting rope must be tied up at the same time insurance. When using out the lifting, must use card ring card. Hang up after the hook line slowly ascend, taut hook line, 500 mm or so stop rising from the ground, carefully check the sling is firm, fastened on the safe side, before lifting in place. Lifting one or local pick on the edge of the beam, to seriously consider its center of gravity position, avoid eccentric, prevent tilt. Lifting point should be close to rings or beam end parts.
3.3.1.2 in place: to check again before lifting the stigma of fulcrum GangDian elevation, whether conform to the requirements of the installation location, in place when looking for a good axis positioning on stigma and the relationship between the beam axis, so that the beam right in place. The two ends of the beam pillar top application.
3.3.2 rainfall distribution on 10-12 calibration and main reinforcement beam welding, in place after the solid, elevation, pivot position of beam correction. Finishing beam reinforced with corresponding to the head of the main reinforcement after each other tight, easy to welding. In order to control the displacement of the beam should be made on both ends of the beam center line at the bottom of the aim point and the positioning line at the top of the pillars, if the error is not big, can use a crowbar slight touch of alignment; When the error is bigger, pry roots are not allowed to use hard to pry, otherwise it will affect the perpendicularity of the pillars of change. Beam should be to lift, slightly away from the pedestal, operators respectively from two balance, visual alignment axis, left hook to smooth, slowly sit down, and then make the bottom of the beam axis on the axis of the pillars. Liang Shen vertical deviation correction from both ends of thread object is, mutual deviation, again with a crowbar beam bottom pad, use iron mat smooth sealed, until both ends of the vertical deviation are controlled within the scope of the permit, the notice in the process of the whole correction, must at the same time use the theodolite observation posts, as vertical change. As a result of beam installation makes the vertical deviation beyond the allowable value of pillars, must be adjusted again. Elevation and pivot position correction, right when the beam topside is firm, can be welding, welding quality should comply with the requirements.
3.4 beam and column joint core processing:
3.4.1 track beam and column core practices to conform to the requirements of the design drawings and building aseismic structure atlas. By using welding closed hoop reinforcement, the entire area encryption stirrup spacing, diameter, number, 135 °, hook, straight section length, etc., shall meet the design requirements and construction norms. In the feng up part of the composite beam should be set 1 phi 12 position of the closed hoop, used to control the correct position of the pillar advocate muscle and joint.
3.4.2 edge, Angle, sealing needle node: lap anchorage length of beam and column the main steel and weld, must meet the requirements of design drawings and seismic code. Position of beam on the top edge Angle joint reinforced except with beam reinforcement under lap welding, reinforced with pillars embedded anchor reinforcement on the rest of the weld. Pillars anchoring reinforcement should be welded (diagonal Settings.
The strength of the concrete rule 3.4.3 node area level should be higher than that of column concrete strength grade 10 mpa. Column joint caulked with dry concrete (weight ratio 1:1:1 harsh pisolite concrete), appropriate USES pouring cement mixture, control the water cement ratio of 0.3, its strength than to concrete strength increased 10 mpa. Caulking seams to be removed before; With hemp rope, hemp sack filling full moisture; The two sides with template. Two people at the same time symmetry with eccentric chisel operation, and fill with the twist. Construction should be maintained 7 d, prevent shrinkage crack. In the upper structure before installation, should be pillars joint parts are completed.
Node area can also be mixed of UEA shrinkage-compensating concrete, the strength grade should be higher than that of column concrete strength grade 10 mpa, the mixture ratio and casting methods to design department agree.
3.5 plate installation (floor or roof panel) : can use hard frame mode branch or direct method is in place.
3.5.1 track of paddle board line of position: on the basis of design drawing board and board beam side seam line of position, mark plate model.
3.5.2 plate in place: the beam or the wall skin clean, check the elevation, the axis of the review. The required plate lifting in place. Related content can be found in the prestressed round orifice plate installation process standards.
Shear wall construction: 3.6 shall be on the floor of the beam, column, the board after the installation is complete, all with interspersed with vertical steel bar inside the hollow beam, and insert the embedded in the horizontal reinforcement and column iron (steel) welded. Joint position should comply with the norms of construction. According to the construction organization design requirements for a good template, pouring concrete vibratory compaction, strengthen the maintenance.
4 quality standards
4.1 ensure projects:
4.4.1 artifacts when lifting concrete strength, joint (joint) of the lower structure internal force under the concrete or mortar strength, must comply with the design requirements and norms. Check the component factory certificate and test report with condition maintenance test specimen.
4.1.2 component model, location, protection anchor must comply with the design requirements, and no deformation and damage phenomenon. Observe or feet quantity inspection and check the lifting record.
4.1.3 component joint (joint) concrete (mortar) must be accurate measurement, cast close-grained, serious maintenance, its strength must meet the design requirements or construction norms. 28 d block observation to inspection standard and inspection test report and the construction record.
4.2 the basic items:
2 beams, columns, plates in place anchorage: axis location, elevation, sit pulp and node structure practice, plate end plugging holes, plate end anchorage, plate width, should meet the design requirements.
4.2.2 joint welding components, should comply with the design requirements and norms. Main reinforcement and connected to the steel plate welding seam length, width, thickness, shall comply with the design requirements and construction norms. Weld surface smooth, uniform wave welding, no sag, flash, and burns, no cracks, porosity, slag inclusion and joint bite edge. Welding slag, coated and splash is clean.
4.3 allowable deviation projects, see table 4-39.
5 finished product protection
5.1 floor column grid axis to keep well versed in, clear, installation node elevation, please indicate need processing should have clearly marked, shall any daub, change and pollution.
5.2 installation of beam and column location up to guarantee the accuracy of the elevation, shall not be any move, touch attack and shift.
Precast frame member allowable deviation of installation and inspection method table 4-39
Will project allow deviation (mm) check method
1 the center line of the column to position the axis offset 5 'quantity check
2 the center line of the column from top to bottom interface position offset 3 feet, quantity check
3 5 m column 5 or less
Four column vertical degree > 5 m column 10 quantity check with theodolite or messenger wire and ruler
More than 5 > 10 m section column 1 ‰ column high and < 20
6 5 m + 0 or less, to 5 level or feet quantity check
7 > 5 m + 0, 8 -
8 axis displacement deviation of 5 feet, quantity check
9 layer + 0 level or feet high quantity check
10 rebounds to shelve length + 10 feet quantity check
Plaster 5 by feet and feeler check
Don't plaster 3
12 the centerline of axis positioning line 5 'quantity check
13 beam beam surface elevation + 0-5 quantity check with level or messenger wire and ruler
14 vertical deviation 3 quantity check with messenger wire and ruler
15 the stairs horizontal displacement and migration 10 feet quantity check
16 the balcony the + / - 5 level, feet high quantity check
5.3 main reinforcement node shall not be skewed, bending, clean up the rust and may not be so heavily in filthy process. Before concrete pouring node with phi 12 steel welded closed localization band, fixed pillars main reinforcement position. Node stirrup encryption area enclosed welding, the spacing comply with the design and the requirements of the seismic atlas, binding is firm.
5.4 has been installed in the beam, column, the board shall not be arbitrarily will remove, support and pull rod should be can be removed after welding of all the main steel cooling calibration facilities. When installing a beam, should observe the verticality change of pillars, produce deviation should be timely to prevent or correct.
5.5 components during transport and storage, bedding position should comply with the provisions of the chock, generally should be close to the rings, the thickness of the block should be higher than the rings, and skid into a straight line up and down. To prevent unreasonable for bedding, component damage. Stacking area should level off, solid, and may not be water. The underlying application 100 mm x 100 mm square timber or double scaffold board smooth bedding. Each pile shall be stipulated in the construction organization design pattern height packed neatly.
5.6 installation of various pipelines, shall not be arbitrarily pick carved artifacts. Construction shall not be arbitrarily cut steel or bent into a hard bending damage to the finished product.
6 should pay attention to quality problems
6.1 component defects: use error component model, specification. The strength of the component factory has yet to reach regulation, cause fracture or damage. In front of the transportation and installation, check the appearance quality of the components, strength of concrete. The right method of handling and transportation. Damaged or defect components without identification technology department, shall not be used.
Component displacement deviation 6.2: before installation components should indicate the type and use of the site, after review the feeding size for installation, prevent the pay-off component offset error. Different adjustment of measuring error of climate change. Operation is serious and responsible, careful calibration. The component location, elevation, verticality meets the requirements.
6.3 don't correspond to the upper and lower axis, in the wrong, impact component installation: construction steel, the upper positioning line should be from the bottom up, using theodolite perpendicular, determine the correct floor axis. Guarantee, between the lower axis perfectly.
Cast concrete imperfect: 6.4 node template is lax running pulp. Before pouring node template seam wall should be strict. Core steel bar is dense, casting should be vibrating in earnest. Concrete has good workability, appropriate slump. Template to be kept cleaning the mouth, clean up seriously, avoid the slag.
: 6.5 the main reinforcement displacement node location below post main reinforcement displacement, create difficulties to lap welding. Reason is the component production when not take measures to control the main reinforcement position; Component in the process of transportation and hoisting cause deformation of the main reinforcement. So the production should take measures to ensure Liang Zhuzhu reinforcement position correctly, avoid collisions when hoisting, straighten out before installation.
6.6 core structure does not conform to the requirements: because of the large core steel bar, so construction should be carefully at the picture, in accordance with the requirements of the node structure construction. Steel bar connection location accurate, overlapping each other tight, easy to weld. The number of stirrups should conform to the requirements of the drawings.
6.7 high floor: the main is to control the elevation is lax in hoisting process, raise the installation elevation. Should from the first beginning, putright plinth epithelial actual relative elevation, find the elevation of the column bottom leveling layer. Installing a floor pillars, to adjust the positioning plate level to control the elevation of floor, node positioning plate application level leveling, according to the actual situation of pillars, pillars set positioning plate negative deviation. Negative deviation in 3 ~ 5 mm advisable, can use steel plate adjustment.
Scape skewed 6.8: reason is bad welding method. Improvement idea is to beam and column joints, there are two or more than two solder joints, welding methods should be adopted to lose flow. Process of welding is not allowed to fierce pry bar, the main steel welding process using theodolite observation column, vertical deviation correcting in time when problems found.
6.9 displacement of pillars: only when in place in accordance with the small stigma on reticle in place, and not controlled the axis of the fust general; The main steel welding, thermal deformation effect produce distortion, lead to displacement of pillars.
6.10 post vertical super wide, scape: straight when installation, should be on both sides of the adjacent verticality calibration pendant with lines. Small stigma on the connecting plate after welding, reoccupy pillars corrector for secondary rectification. Symmetry is used in the main reinforcement, constant speed, intermittent welds. Reasonable welding sequence arrangement, plum point should be adopted from the framework of the whole stagger welding method, prevent due to the effect of uneven stress during welding, to avoid frame to produce different degree of deformation.
6.11 welding quality does not meet the requirements, should strictly abide by the welding procedures.
7 quality records
This technology standard should have the quality records
7.1 component factory certificate.
7.2 steel factory certificate.
7.3 steel mill certificate and mechanical properties of the second interview report.
7.4 electrode factory certificate.
7.5 welders working certificate.
7.6 the welding test report.
7.7 cement factory certification and retest report.
7.8 sand, stone test report.
7.9 structure lifting record record (preview).
7.10 concrete block strength of 28 d report.
7.11 component installation engineering quality inspection record separately.
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