1 scope
The technology standard is applicable to industrial and civil building pile foundation apron piece.
2 construction preparation
2.1 material and main equipments:
2.1.1 cement: appropriate USES 325 ~ 425 slag Portland cement and ordinary Portland cement.
2.1.2 sand, medium sand and coarse sand and silt content is not more than 5%. Water: tap water or clean water does not contain harmful substances.
2.1.3 stones, pebbles or gravel, particle size of 5 ~ 32 mm, silt content is not more than 2%.
2.1.4 reinforced: reinforced level, diameter must comply with the design requirements, has the certificate of the factory and retest report, surface rust and oil free.
2.1.5 block: in 1, 3 cement mortar buried 22 large burn silk prefabricated into or use the plastic pad in advance.
2.1.6 HuoShaoSi: specifications 18 ~ 20 wire burning.
2.1.7 additive and admixture, according to the requirements of the construction determined by experiment.
2.1.8 main machine
2.1.8.1 concrete: should be equipped with the scale, concrete mixer, internal vibrator, pointed shovel ping, rubber tube, carts, wood float and iron plate, etc.
2.1.8.2 tie bar: should be equipped with steel hooks, spanner, small crowbar, pole HuoShaoSi (cut off), hook machine, folding rule of wood and the composite steel template, etc.
2.2 operation conditions:
2.2.1 pile foundation construction has been completed, and dig the soil, according to the requirements of design and acceptance record through with pile foundation construction.
2.2.2 repairing concrete pile head: loose concrete pile head carved out entirely, such as pile top is lower than the design elevation, must use high concrete, at the same level is reached more than 50% of the strength of pile, and then embedded in the apron piece stuck between pile top part of the hair, rinse. Such as pile top is higher than the design elevation, carved chisel in advance, make the cap into the depth of the apron piece fully comply with the design requirements.
2.2.3 cap into the apron piece of steel bar should comply with the design requirements, generally not less than 30 d, reinforcement length is not enough, must be paid to the extension.
2.2.4 for frost heaving soil area, should be done according to the design requirements for apron piece winterizing expansion treatment measures.
2.2.5 trough bottom XuTu, debris and garbage removal should be clean.
3 operation process
3.1 process:
Check the semi-finished products - steel binding - embedded pipeline steel and ironwork to tie up mortar pad
3.1.1 reinforcement assembling process:
Assembled steel template scheme determined to assemble steel template, the template preview
3.1.3 concrete pouring process:
Mixing concrete and pouring and vibrating and curing
3.2 steel binding:
Check the rebar semi-finished products: 3.2.1 should be checked according to the design drawing first processing of semi-finished steel, to its specifications, shapes, types, varieties tested, and stacking.
3.2.2 steel binding: rebar shall be binding in sequence, under normal circumstances, the first long axis after the short axis, from one end to the other end. Operation according to the requirements of drawing scribing and iron, wear a collar and tie, the final shape.
3.2.3 embedded pipeline and ironwork: the reserved hole position should be correct, pile into the apron piece of steel, apron piece of pillar, wall on the iron, all should tie up according to the drawing, tied firmly (cross) should be adopted or welded, the elevation, position and lap anchorage length dimension should be accurate, shall not be omitted or displacement.
3.2.4 reinforced location of lap joint should be correct. Its joints staggered, feng in across the iron ruler under the quantity in the bearing; Each within the scope of the length of the lap joint, lap steel area should not be more than the steel with a total area of about a quarter of the length range. All mechanical reinforcement and stirrup junction are all the tie, can not jump buckle.
3.2.5 binding mortar pad: at the bottom of the reinforced mortar pad, under the general thickness of not less than 50 mm, interval of 1 m, the block of side shall be the rebar tie, should not be missed.
3.3 installation template:
3.3.1 determine assembly steel formwork plan: should first make a apron piece assembly scheme of steel template, and the calculate and determine the bolt diameter, length, position and vertical and horizontal keels, spacing and size of connecting rod point, in case of steel template does not conform to the module, it can be another template seams.
Installed 3.3.2 rainfall distribution on 10-12 steel template, combination steel template, combination steel template template, Yin and Yang Angle by the plane template together. The vertical and horizontal side stitching with u-shaped card, bolt and other parts, requirements are complete and firm, not loose, not omission.
3.3.3 template preview: template after installation, section size, elevation, to preview of bolt, connecting rod support, and so on, all should comply with the requirements of design drawings and quality standard.
Concrete pouring 3.4:
3.4.1 track mixing: according to the mixture ratio weigh out the weight of the each plate of cement, sand, stone and the dosage of admixture. Operation to each car weighing, pour the stones and then pour cement, after down, sand and water mixing. Admixture in general to join with the water. The first set stirring to enforce the rules of the open quotation approval.
3.4.2 casting, pile head and the bottom of the channel and help mold (block) should be water wetting. Apron piece casting concrete, in order to concrete directly into the mold Such as rejection if more than the initial setting time, should be handled in accordance with the requirements of construction joints. If use tower crane lifting bucket directly discharge into the mold, the hoisting bucket discharging mouth with 30 ~ 40 cm high from operation side, and shall not be a dump.
Rule 3.4.3 vibrating: should be along the order of the apron piece casting direction, the oblique vibrating method, vibration rods around 30 ° with the horizontal plane Angle. Rod head towards the direction, the plunger distance with 50 cm advisable, to prevent leakage. The vibrating time will be subject to the air bubbles pumping concrete surface. Concrete surface increases with the increasing of vibration should be according to the elevation lines, flat with wood float rub.
3.4.4 leave meet if: vertical and horizontal join and leave if cap should not be commonly. Leave if should be within the scope of a third in the middle of the two adjacent pile, jilt rub place should advance with the template is good, retained if straight. Continue to construction, if concrete application first wetting and pouring water slurry, the old and new concrete joint is good; Then using the original strength grade of concrete pouring.
3.4.5 maintenance: after concrete pouring, 12 h should be covered under the condition of the water conservation, watering frequency it is advisable to keep the concrete moist, maintenance time is not less than seven days and nights.
3.5 winter construction:
The appropriate 3.5.1 track of reinforcing steel welding in indoor. Outside, when welding the lowest temperature should not be less than 20 ℃, and shall have the snow wind prevention measures. After welding joint are strictly prohibited immediately touched snow and ice.
3.5.2 mixing concrete, may not with ice and snow and ice in the aggregate, mixing time shall be 50% longer than normal.
3.5.3 foundation soil should be heat preservation, shall not be cold.
3.5.4 of concrete curing should be executed according to winter plan. Concrete block should increase in two groups, and structure with the condition maintenance.
4 quality standards
4.1 steel component project:
4.4.1 guarantee project:
4.1.1.1 steel varieties, quality, welding rod, flux of the brand, performance must comply with the design requirements and the provisions of the relevant standards. Imports of steel chemical composition inspection must be conducted before welding and welding test, comply with the relevant provisions of the rear can welding.
4.1.1.2 reinforced surface must be clean. With granule or flake old rust after cleaning the remains pitting reinforcement, it is strictly prohibited to use as stipulated.
4.1.1.3 reinforced specifications, shape, size, number, spacing and anchorage length, joint setting, must comply with the design requirements and norms.
4.1.1.4 welding joint, the mechanical properties of welding products must comply with the special provisions of rebar welding and acceptance.
4.1.2 basic items:
4.1.2.1 banding steel button missing, string quantity does not exceed 10% of the total, and should not be concentrated.
4.1.2.2 hook orientation should be correct. Binding joint should comply with the construction norms, lap length is not less than the specified value.
4.1.2.3 made of grade Ⅰ reinforcement stirrup, the number of comply with the design requirements, the Angle of the hook peace straight length should comply with the norms of construction.
4.1.2.4 butt joint without the transverse crack and burn, welding package. Bending joint is not greater than 4 °, reinforcement joint axis displacement shall not be greater than 0.1 d, and not greater than 2 mm.
4.1.2.5 arc welding joint weld surface level off, without cave, flash, no cracks, porosity, slag and joint bite edge. Article shall bind the longitudinal displacement along the center line of the joint shall not be greater than 0.5 d, and not more than 3 mm; Displacement of the axis of the reinforced joint is not greater than 0.1 d, and no more than 3 mm; Weld thickness is not less than 0.05 d; Weld width is not less than 0.1 d; Weld length of not less than 0.5 d; Bending joint is not greater than 4 °.
4.1.3 allowable deviation, see table 2-10.
4.2 the template component project:
2 ensure projects:
4.2.1.1 template and its bracket must have sufficient strength, stiffness and stability, the support of supporting part have enough bearing area.
4.2.1.2 templates installed on the base of soil, the soil must be solid and drainage measures.
4.2.2 basic items:
4.2.2.1 seams template juncture of maximum width should not be greater than 1.5 mm.
4.2.2.2 template and concrete contact surface should be clean, and take measures to prevent caking. Mucilage and leakage isolation agent area is not greater than 1000 cm2.
Holdings allow deviation, see table 2-11.
Pile caps of reinforced installation and embedded parts position deviation table allowed 2-10
Will project allowable deviation check method (mm)
1 frame width and height of the plus or minus 5 'quantity check
2 the length of the skeleton plus or minus 10 feet quantity check
Welded tubing plus or minus 10 feet for three gears
To + 20 take its maximum
Distance between plus or minus 10 feet at both ends, all in the middle
From + 5 to maximize its number one
5 the starting point of reinforced bending displacement quantity of 20 feet
Displacement of the center line of the five
Level elevation difference + 3 to 0
7 reinforced protective layer based plus or minus 10 feet quantity check
Pile caps template installation and allowable deviation of embedded object in table 2 to 11
Will project allowable deviation (mm) test method
1 5 foot axis displacement quantity check
2 the high plus or minus 5 level or pull inspection
3 section size plus or minus 10 feet quantity check
4 two adjacent plate surface height 2 quantity check with ruler and ruler
5 the surface roughness in 2 m by feet and feeler check
6 embedded steel axis displacement quantity check 3 arrows and ruler
The reserved hole centerline 7 embedded pipe displacement quantity check 3 arrows and ruler
Displacement of the center line of the 2
The leakage length + 10 0
Displacement of the center line of the ten
Section internal size + 10 0
4.3 concrete subentry project:
This will ensure projects:
4.3.1.1 concrete used in cement, water, aggregate, admixtures such as must comply with the provisions of the construction specification and relevant standards.
4.3.1.2 the mixing proportion of concrete, metering, mixing, maintenance and construction joint treatment of raw materials must conform to the norms of construction.
4.3.1.3 assess the strength of the concrete block, according to the concrete strength inspection criteria (GBJ107-87), the provisions of the sampling, production, maintenance and test, its strength must conform to the norms of construction.
4.3.1.4 to design the structure of the cracks are not allowed to have, it is forbidden to crack; Design allows the structure of the cracks, the crack width must comply with the design requirements.
4.3.2 basic items:
4.3.2.1 concrete should be vibrating close-grained, cellular area is not more than 200 cm2, accumulative total is not more than 400 cm2, no holes.
4.3.2.2 a main reinforcement shall not have any leakage.
4.3.2.3 without gap slag layer.
4.3.3 allowable deviation, see table 2-12.
Pile caps concrete engineering allows 2-12 gauge
Will project allowable deviation (mm) test method
1 10 feet axis displacement quantity check
2 high standard plus or minus 10 with level or stay 'quantity check
3 + 15, section size - 10 feet quantity check
4 surface roughness 8 in 2 m by feet and feeler check
5 embedded steel inspecting centerline offset amount 10 feet
6 embedded bolt inspecting centerline offset amount of 5 ft
7 reserve tube, the reserved hole centerline offset 5 'quantity check
8 the reserved hole centerline offset 15 feet quantity check
5 finished product protection
5.1 installation template and pouring concrete, should pay attention to protect steel, not climbing on steel.
5.2 reinforced concrete cover thickness is generally not less than 50 mm. The reinforced block shall not be missed.
5.3 winter construction should be covering insulation materials, prevent concrete seas.
5.4 to avoid dismantle pry, hard to hit, in order to avoid the damage of concrete and steel template.
6 should pay attention to quality problems
Honeycomb, 6.1: as the template stitching is lax, concrete slurry leakage cause cellular; Vibrating not according to the process operation, causing the vibration is not dense and exposure.
6.2 lack of edge, Angle, mix proportion, mixing uneven or early to dismantle, maintenance is not enough, will cause concrete edge damage.
Deviation is too big: 6.3 template support, clip, tie spacing is too large, or not strong; Too high or vibrating concrete pouring time is too long, can cause concrete bulging belly, wrong Taiwan, defects such as tilt.
6.4 in iron steel bar displacement: iron fixed weak, vibrating rod or tower crane steel hopper collision, the steel bar displacement.
6.5 for the earthquake fortification zones, when apron piece adopt the die casting, apron piece side should be in accordance with the requirements of design and backfill soil compaction.
7 quality records
This technology standard should have the following quality records
7.1 cement factory certificate and the reinspection do not coincide.
7.2 steel factory certificate or certificate of approval, acceptance certificate and steel tineke.
7.3 steel concealed acceptance records.
7.4 template elevation, the size of the preview.
7.5 steel welded joint tensile test report.
7.6 structure with concrete should try apps and mix notice issued by the laboratory.
7.7 concrete block 28 d standard compressive strength test report. Commercial concrete shall have the factory certificate.
The technology standard is applicable to industrial and civil building pile foundation apron piece.
2 construction preparation
2.1 material and main equipments:
2.1.1 cement: appropriate USES 325 ~ 425 slag Portland cement and ordinary Portland cement.
2.1.2 sand, medium sand and coarse sand and silt content is not more than 5%. Water: tap water or clean water does not contain harmful substances.
2.1.3 stones, pebbles or gravel, particle size of 5 ~ 32 mm, silt content is not more than 2%.
2.1.4 reinforced: reinforced level, diameter must comply with the design requirements, has the certificate of the factory and retest report, surface rust and oil free.
2.1.5 block: in 1, 3 cement mortar buried 22 large burn silk prefabricated into or use the plastic pad in advance.
2.1.6 HuoShaoSi: specifications 18 ~ 20 wire burning.
2.1.7 additive and admixture, according to the requirements of the construction determined by experiment.
2.1.8 main machine
2.1.8.1 concrete: should be equipped with the scale, concrete mixer, internal vibrator, pointed shovel ping, rubber tube, carts, wood float and iron plate, etc.
2.1.8.2 tie bar: should be equipped with steel hooks, spanner, small crowbar, pole HuoShaoSi (cut off), hook machine, folding rule of wood and the composite steel template, etc.
2.2 operation conditions:
2.2.1 pile foundation construction has been completed, and dig the soil, according to the requirements of design and acceptance record through with pile foundation construction.
2.2.2 repairing concrete pile head: loose concrete pile head carved out entirely, such as pile top is lower than the design elevation, must use high concrete, at the same level is reached more than 50% of the strength of pile, and then embedded in the apron piece stuck between pile top part of the hair, rinse. Such as pile top is higher than the design elevation, carved chisel in advance, make the cap into the depth of the apron piece fully comply with the design requirements.
2.2.3 cap into the apron piece of steel bar should comply with the design requirements, generally not less than 30 d, reinforcement length is not enough, must be paid to the extension.
2.2.4 for frost heaving soil area, should be done according to the design requirements for apron piece winterizing expansion treatment measures.
2.2.5 trough bottom XuTu, debris and garbage removal should be clean.
3 operation process
3.1 process:
Check the semi-finished products - steel binding - embedded pipeline steel and ironwork to tie up mortar pad
3.1.1 reinforcement assembling process:
Assembled steel template scheme determined to assemble steel template, the template preview
3.1.3 concrete pouring process:
Mixing concrete and pouring and vibrating and curing
3.2 steel binding:
Check the rebar semi-finished products: 3.2.1 should be checked according to the design drawing first processing of semi-finished steel, to its specifications, shapes, types, varieties tested, and stacking.
3.2.2 steel binding: rebar shall be binding in sequence, under normal circumstances, the first long axis after the short axis, from one end to the other end. Operation according to the requirements of drawing scribing and iron, wear a collar and tie, the final shape.
3.2.3 embedded pipeline and ironwork: the reserved hole position should be correct, pile into the apron piece of steel, apron piece of pillar, wall on the iron, all should tie up according to the drawing, tied firmly (cross) should be adopted or welded, the elevation, position and lap anchorage length dimension should be accurate, shall not be omitted or displacement.
3.2.4 reinforced location of lap joint should be correct. Its joints staggered, feng in across the iron ruler under the quantity in the bearing; Each within the scope of the length of the lap joint, lap steel area should not be more than the steel with a total area of about a quarter of the length range. All mechanical reinforcement and stirrup junction are all the tie, can not jump buckle.
3.2.5 binding mortar pad: at the bottom of the reinforced mortar pad, under the general thickness of not less than 50 mm, interval of 1 m, the block of side shall be the rebar tie, should not be missed.
3.3 installation template:
3.3.1 determine assembly steel formwork plan: should first make a apron piece assembly scheme of steel template, and the calculate and determine the bolt diameter, length, position and vertical and horizontal keels, spacing and size of connecting rod point, in case of steel template does not conform to the module, it can be another template seams.
Installed 3.3.2 rainfall distribution on 10-12 steel template, combination steel template, combination steel template template, Yin and Yang Angle by the plane template together. The vertical and horizontal side stitching with u-shaped card, bolt and other parts, requirements are complete and firm, not loose, not omission.
3.3.3 template preview: template after installation, section size, elevation, to preview of bolt, connecting rod support, and so on, all should comply with the requirements of design drawings and quality standard.
Concrete pouring 3.4:
3.4.1 track mixing: according to the mixture ratio weigh out the weight of the each plate of cement, sand, stone and the dosage of admixture. Operation to each car weighing, pour the stones and then pour cement, after down, sand and water mixing. Admixture in general to join with the water. The first set stirring to enforce the rules of the open quotation approval.
3.4.2 casting, pile head and the bottom of the channel and help mold (block) should be water wetting. Apron piece casting concrete, in order to concrete directly into the mold Such as rejection if more than the initial setting time, should be handled in accordance with the requirements of construction joints. If use tower crane lifting bucket directly discharge into the mold, the hoisting bucket discharging mouth with 30 ~ 40 cm high from operation side, and shall not be a dump.
Rule 3.4.3 vibrating: should be along the order of the apron piece casting direction, the oblique vibrating method, vibration rods around 30 ° with the horizontal plane Angle. Rod head towards the direction, the plunger distance with 50 cm advisable, to prevent leakage. The vibrating time will be subject to the air bubbles pumping concrete surface. Concrete surface increases with the increasing of vibration should be according to the elevation lines, flat with wood float rub.
3.4.4 leave meet if: vertical and horizontal join and leave if cap should not be commonly. Leave if should be within the scope of a third in the middle of the two adjacent pile, jilt rub place should advance with the template is good, retained if straight. Continue to construction, if concrete application first wetting and pouring water slurry, the old and new concrete joint is good; Then using the original strength grade of concrete pouring.
3.4.5 maintenance: after concrete pouring, 12 h should be covered under the condition of the water conservation, watering frequency it is advisable to keep the concrete moist, maintenance time is not less than seven days and nights.
3.5 winter construction:
The appropriate 3.5.1 track of reinforcing steel welding in indoor. Outside, when welding the lowest temperature should not be less than 20 ℃, and shall have the snow wind prevention measures. After welding joint are strictly prohibited immediately touched snow and ice.
3.5.2 mixing concrete, may not with ice and snow and ice in the aggregate, mixing time shall be 50% longer than normal.
3.5.3 foundation soil should be heat preservation, shall not be cold.
3.5.4 of concrete curing should be executed according to winter plan. Concrete block should increase in two groups, and structure with the condition maintenance.
4 quality standards
4.1 steel component project:
4.4.1 guarantee project:
4.1.1.1 steel varieties, quality, welding rod, flux of the brand, performance must comply with the design requirements and the provisions of the relevant standards. Imports of steel chemical composition inspection must be conducted before welding and welding test, comply with the relevant provisions of the rear can welding.
4.1.1.2 reinforced surface must be clean. With granule or flake old rust after cleaning the remains pitting reinforcement, it is strictly prohibited to use as stipulated.
4.1.1.3 reinforced specifications, shape, size, number, spacing and anchorage length, joint setting, must comply with the design requirements and norms.
4.1.1.4 welding joint, the mechanical properties of welding products must comply with the special provisions of rebar welding and acceptance.
4.1.2 basic items:
4.1.2.1 banding steel button missing, string quantity does not exceed 10% of the total, and should not be concentrated.
4.1.2.2 hook orientation should be correct. Binding joint should comply with the construction norms, lap length is not less than the specified value.
4.1.2.3 made of grade Ⅰ reinforcement stirrup, the number of comply with the design requirements, the Angle of the hook peace straight length should comply with the norms of construction.
4.1.2.4 butt joint without the transverse crack and burn, welding package. Bending joint is not greater than 4 °, reinforcement joint axis displacement shall not be greater than 0.1 d, and not greater than 2 mm.
4.1.2.5 arc welding joint weld surface level off, without cave, flash, no cracks, porosity, slag and joint bite edge. Article shall bind the longitudinal displacement along the center line of the joint shall not be greater than 0.5 d, and not more than 3 mm; Displacement of the axis of the reinforced joint is not greater than 0.1 d, and no more than 3 mm; Weld thickness is not less than 0.05 d; Weld width is not less than 0.1 d; Weld length of not less than 0.5 d; Bending joint is not greater than 4 °.
4.1.3 allowable deviation, see table 2-10.
4.2 the template component project:
2 ensure projects:
4.2.1.1 template and its bracket must have sufficient strength, stiffness and stability, the support of supporting part have enough bearing area.
4.2.1.2 templates installed on the base of soil, the soil must be solid and drainage measures.
4.2.2 basic items:
4.2.2.1 seams template juncture of maximum width should not be greater than 1.5 mm.
4.2.2.2 template and concrete contact surface should be clean, and take measures to prevent caking. Mucilage and leakage isolation agent area is not greater than 1000 cm2.
Holdings allow deviation, see table 2-11.
Pile caps of reinforced installation and embedded parts position deviation table allowed 2-10
Will project allowable deviation check method (mm)
1 frame width and height of the plus or minus 5 'quantity check
2 the length of the skeleton plus or minus 10 feet quantity check
Welded tubing plus or minus 10 feet for three gears
To + 20 take its maximum
Distance between plus or minus 10 feet at both ends, all in the middle
From + 5 to maximize its number one
5 the starting point of reinforced bending displacement quantity of 20 feet
Displacement of the center line of the five
Level elevation difference + 3 to 0
7 reinforced protective layer based plus or minus 10 feet quantity check
Pile caps template installation and allowable deviation of embedded object in table 2 to 11
Will project allowable deviation (mm) test method
1 5 foot axis displacement quantity check
2 the high plus or minus 5 level or pull inspection
3 section size plus or minus 10 feet quantity check
4 two adjacent plate surface height 2 quantity check with ruler and ruler
5 the surface roughness in 2 m by feet and feeler check
6 embedded steel axis displacement quantity check 3 arrows and ruler
The reserved hole centerline 7 embedded pipe displacement quantity check 3 arrows and ruler
Displacement of the center line of the 2
The leakage length + 10 0
Displacement of the center line of the ten
Section internal size + 10 0
4.3 concrete subentry project:
This will ensure projects:
4.3.1.1 concrete used in cement, water, aggregate, admixtures such as must comply with the provisions of the construction specification and relevant standards.
4.3.1.2 the mixing proportion of concrete, metering, mixing, maintenance and construction joint treatment of raw materials must conform to the norms of construction.
4.3.1.3 assess the strength of the concrete block, according to the concrete strength inspection criteria (GBJ107-87), the provisions of the sampling, production, maintenance and test, its strength must conform to the norms of construction.
4.3.1.4 to design the structure of the cracks are not allowed to have, it is forbidden to crack; Design allows the structure of the cracks, the crack width must comply with the design requirements.
4.3.2 basic items:
4.3.2.1 concrete should be vibrating close-grained, cellular area is not more than 200 cm2, accumulative total is not more than 400 cm2, no holes.
4.3.2.2 a main reinforcement shall not have any leakage.
4.3.2.3 without gap slag layer.
4.3.3 allowable deviation, see table 2-12.
Pile caps concrete engineering allows 2-12 gauge
Will project allowable deviation (mm) test method
1 10 feet axis displacement quantity check
2 high standard plus or minus 10 with level or stay 'quantity check
3 + 15, section size - 10 feet quantity check
4 surface roughness 8 in 2 m by feet and feeler check
5 embedded steel inspecting centerline offset amount 10 feet
6 embedded bolt inspecting centerline offset amount of 5 ft
7 reserve tube, the reserved hole centerline offset 5 'quantity check
8 the reserved hole centerline offset 15 feet quantity check
5 finished product protection
5.1 installation template and pouring concrete, should pay attention to protect steel, not climbing on steel.
5.2 reinforced concrete cover thickness is generally not less than 50 mm. The reinforced block shall not be missed.
5.3 winter construction should be covering insulation materials, prevent concrete seas.
5.4 to avoid dismantle pry, hard to hit, in order to avoid the damage of concrete and steel template.
6 should pay attention to quality problems
Honeycomb, 6.1: as the template stitching is lax, concrete slurry leakage cause cellular; Vibrating not according to the process operation, causing the vibration is not dense and exposure.
6.2 lack of edge, Angle, mix proportion, mixing uneven or early to dismantle, maintenance is not enough, will cause concrete edge damage.
Deviation is too big: 6.3 template support, clip, tie spacing is too large, or not strong; Too high or vibrating concrete pouring time is too long, can cause concrete bulging belly, wrong Taiwan, defects such as tilt.
6.4 in iron steel bar displacement: iron fixed weak, vibrating rod or tower crane steel hopper collision, the steel bar displacement.
6.5 for the earthquake fortification zones, when apron piece adopt the die casting, apron piece side should be in accordance with the requirements of design and backfill soil compaction.
7 quality records
This technology standard should have the following quality records
7.1 cement factory certificate and the reinspection do not coincide.
7.2 steel factory certificate or certificate of approval, acceptance certificate and steel tineke.
7.3 steel concealed acceptance records.
7.4 template elevation, the size of the preview.
7.5 steel welded joint tensile test report.
7.6 structure with concrete should try apps and mix notice issued by the laboratory.
7.7 concrete block 28 d standard compressive strength test report. Commercial concrete shall have the factory certificate.
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