1 scope
The technology standard is applicable to industrial and civil construction in the concrete foundation.
2 construction preparation
2.1 material and main equipments:
2.1.1 cement: appropriate USES 325 ~ 425 Portland cement, slag Portland cement and ordinary Portland cement.
2.1.2 sand, medium sand and coarse sand and silt content is not more than 5%.
2.1.3 stones, pebbles or gravel, particle size of 5 ~ 32 mm, silt content is not more than 2%, and no clutter.
2.1.4 water: tap water or clean water does not contain harmful substances.
2.1.5 additive and admixture, the varieties and dosage, should be determined by test according to need.
2.1.6 main machine, mixer, the scale, carts or skip (flat head and tip), a spade, vibrator (plug-in peace plate), scraping bars, wood trowel, rubber tubes, string or chute, etc.
2.2 operation conditions:
2.2.1 base size, basal elevation axes and geology are checked, and should be completed implicit inspection procedures.
2.2.2 installation template has been checked, comply with the design requirements, through engineering.
2.2.3 in tank, walls or template help make concrete flat logo, large casting based on the nail at intervals of about 3 m level.
2.2.4 buried in the cushion layer premaking parts, electrical and other pipeline have been installed, and through the acceptance.
2.2.5 checking concrete mixture ratio, and check the background the scale, technical clarificaiton. Ready to concrete test mode.
3 operation process
3.1 process:
Cleaning up inside the bottom of the channel or template to concrete mix, concrete pouring to concrete vibratory, concrete curing
3.2 clean: remove mud and debris on the foundation and foundation soil, and shall have the waterproof and drainage measures. For dry soil applied water wetting, there shall not be surface water. Within the mold plate remove rubbish, soil and other sundry, water wettability and wooden template, blocking plate seams and holes.
3.3 concrete mixing: background to charge: according to the concrete mixture ratio per plate feeding sequence for stones to cement, sand (admixture) and water (additive). Strict control of water, stir evenly, the shortest time not less than 90 s.
3.4 the pouring of concrete
3.4.1 track of concrete pouring the concrete surface height of the feed opening distance shall not be more than 2 m. Such as free pour down more than 2 m, should use string barrels or chute.
3.4.2 the pouring of concrete should be layered continuous, general layer thickness for the vibrator 1.25 times the length of the part, the biggest is not more than 50 cm.
Rule 3.4.3 inserted with internal vibrator should fast slow, pull plug point should be evenly arranged, point by point, order, shall not be omitted, vibrating compaction. Mobile spacing is not greater than 1.5 times of vibrating rod action radius. Should be inserted into the lower vibration on a layer of 5 cm, to clear the joint between the two layers. Flat vibrator mobile spacing, should ensure the edge of the vibrator plate cover is vibrating.
3.4.4 concrete can't continuous casting, generally more than 2 h, should be in accordance with the construction joint treatment.
3.4.5 pouring concrete, often should observe template, stents, and obligate hole and embedded parts for walking around. When found deformation, displacement, should immediately stop pouring, and handle in time, to continue pouring.
3.4.6 concrete vibratory compaction, wood float rub flat surface application.
3.4.7 of concrete curing: after the concrete pouring, should cover within 12 h and watering, watering frequency should be able to maintain enough concrete wetting state. Curing period is generally not less than seven days and nights.
3.4.8 rain, winter construction, open casting concrete should prepare the seasonal construction plan, take effective measures to ensure the quality of the concrete.
4 quality standards
4.1 ensure projects:
4.4.1 concrete used in cement, water, aggregate, admixtures must comply with the provisions of the construction specification and relevant standards.
4.1.2 the mixing proportion of concrete, metering, mixing of raw materials and maintenance and construction joint treatment, must comply with the norms of construction.
4.1.3 assess the strength of the concrete block, must according to the concrete strength inspection criteria (GBJ107-87), the provisions of the sampling, production, maintenance and test. Its strength must conform to the construction of the norms.
4.1.4 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.
4.2 infrastructure projects:
2 should concrete vibrating close-grained, cellular area is not more than 200 cm2, accumulative total is not more than 400 cm2, no holes.
4.2.2 without gap slag layer.
4.3 allowable deviation projects, see table 2-14.
Plain concrete foundation to allow deviation table 2-14
Will project allowable deviation (mm) test method
1 label high plus or minus 10 level or stay 'quantity check
Surface roughness 8 in 2 m by 2 feet and wedge feeler check
3 basic axis displacement 15 with theodolite or stay 'quantity check
Four basic section size + 15-10 feet quantity check
5 ft 5 reserved hole centerline displacement quantity check
5 finished product protection
5.1 in concrete strength can guarantee its surface and edges and not damaged by dismantling templates, template can dismantle the side.
5.2 in the pouring of concrete strength is 5.2 MPa, can on the passers-by and the upper part of the construction.
5.3 in the construction, should protect the warm who, electrical drainage tubes and reserved hole, avoid collision.
5.4 basis should be placed according to design requirements reserved holes or bolt and embedded parts, in order to avoid the chisel concrete.
5.5 winter construction of concrete surface should be covered insulation materials, prevent concrete seas.
6 should pay attention to quality problems
6.1 concrete close-grained, not have honeycomb pitting surface, mainly owing to the bad vibration is not allowed, leakage, mixture of vibration or template to causes such as crack in plasma.
Inaccurate surface uneven, elevation, size: 6.2 because of the level mark line or peg, operation is not seriously leveling, or template support causes such as not firm.
6.3 gap slag: concrete construction joints is bad, have stuff. Is mainly caused by careful cleaning.
6.4 irregular cracks: base is too long and contraction, lower concrete combining with bad, maintenance is not enough, or early to dismantle.
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 template elevation, the axis, the size of the preview.
7.3 structure with concrete should try apps and mix notice issued by the laboratory.
7.4 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 construction in the concrete foundation.
2 construction preparation
2.1 material and main equipments:
2.1.1 cement: appropriate USES 325 ~ 425 Portland cement, slag Portland cement and ordinary Portland cement.
2.1.2 sand, medium sand and coarse sand and silt content is not more than 5%.
2.1.3 stones, pebbles or gravel, particle size of 5 ~ 32 mm, silt content is not more than 2%, and no clutter.
2.1.4 water: tap water or clean water does not contain harmful substances.
2.1.5 additive and admixture, the varieties and dosage, should be determined by test according to need.
2.1.6 main machine, mixer, the scale, carts or skip (flat head and tip), a spade, vibrator (plug-in peace plate), scraping bars, wood trowel, rubber tubes, string or chute, etc.
2.2 operation conditions:
2.2.1 base size, basal elevation axes and geology are checked, and should be completed implicit inspection procedures.
2.2.2 installation template has been checked, comply with the design requirements, through engineering.
2.2.3 in tank, walls or template help make concrete flat logo, large casting based on the nail at intervals of about 3 m level.
2.2.4 buried in the cushion layer premaking parts, electrical and other pipeline have been installed, and through the acceptance.
2.2.5 checking concrete mixture ratio, and check the background the scale, technical clarificaiton. Ready to concrete test mode.
3 operation process
3.1 process:
Cleaning up inside the bottom of the channel or template to concrete mix, concrete pouring to concrete vibratory, concrete curing
3.2 clean: remove mud and debris on the foundation and foundation soil, and shall have the waterproof and drainage measures. For dry soil applied water wetting, there shall not be surface water. Within the mold plate remove rubbish, soil and other sundry, water wettability and wooden template, blocking plate seams and holes.
3.3 concrete mixing: background to charge: according to the concrete mixture ratio per plate feeding sequence for stones to cement, sand (admixture) and water (additive). Strict control of water, stir evenly, the shortest time not less than 90 s.
3.4 the pouring of concrete
3.4.1 track of concrete pouring the concrete surface height of the feed opening distance shall not be more than 2 m. Such as free pour down more than 2 m, should use string barrels or chute.
3.4.2 the pouring of concrete should be layered continuous, general layer thickness for the vibrator 1.25 times the length of the part, the biggest is not more than 50 cm.
Rule 3.4.3 inserted with internal vibrator should fast slow, pull plug point should be evenly arranged, point by point, order, shall not be omitted, vibrating compaction. Mobile spacing is not greater than 1.5 times of vibrating rod action radius. Should be inserted into the lower vibration on a layer of 5 cm, to clear the joint between the two layers. Flat vibrator mobile spacing, should ensure the edge of the vibrator plate cover is vibrating.
3.4.4 concrete can't continuous casting, generally more than 2 h, should be in accordance with the construction joint treatment.
3.4.5 pouring concrete, often should observe template, stents, and obligate hole and embedded parts for walking around. When found deformation, displacement, should immediately stop pouring, and handle in time, to continue pouring.
3.4.6 concrete vibratory compaction, wood float rub flat surface application.
3.4.7 of concrete curing: after the concrete pouring, should cover within 12 h and watering, watering frequency should be able to maintain enough concrete wetting state. Curing period is generally not less than seven days and nights.
3.4.8 rain, winter construction, open casting concrete should prepare the seasonal construction plan, take effective measures to ensure the quality of the concrete.
4 quality standards
4.1 ensure projects:
4.4.1 concrete used in cement, water, aggregate, admixtures must comply with the provisions of the construction specification and relevant standards.
4.1.2 the mixing proportion of concrete, metering, mixing of raw materials and maintenance and construction joint treatment, must comply with the norms of construction.
4.1.3 assess the strength of the concrete block, must according to the concrete strength inspection criteria (GBJ107-87), the provisions of the sampling, production, maintenance and test. Its strength must conform to the construction of the norms.
4.1.4 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.
4.2 infrastructure projects:
2 should concrete vibrating close-grained, cellular area is not more than 200 cm2, accumulative total is not more than 400 cm2, no holes.
4.2.2 without gap slag layer.
4.3 allowable deviation projects, see table 2-14.
Plain concrete foundation to allow deviation table 2-14
Will project allowable deviation (mm) test method
1 label high plus or minus 10 level or stay 'quantity check
Surface roughness 8 in 2 m by 2 feet and wedge feeler check
3 basic axis displacement 15 with theodolite or stay 'quantity check
Four basic section size + 15-10 feet quantity check
5 ft 5 reserved hole centerline displacement quantity check
5 finished product protection
5.1 in concrete strength can guarantee its surface and edges and not damaged by dismantling templates, template can dismantle the side.
5.2 in the pouring of concrete strength is 5.2 MPa, can on the passers-by and the upper part of the construction.
5.3 in the construction, should protect the warm who, electrical drainage tubes and reserved hole, avoid collision.
5.4 basis should be placed according to design requirements reserved holes or bolt and embedded parts, in order to avoid the chisel concrete.
5.5 winter construction of concrete surface should be covered insulation materials, prevent concrete seas.
6 should pay attention to quality problems
6.1 concrete close-grained, not have honeycomb pitting surface, mainly owing to the bad vibration is not allowed, leakage, mixture of vibration or template to causes such as crack in plasma.
Inaccurate surface uneven, elevation, size: 6.2 because of the level mark line or peg, operation is not seriously leveling, or template support causes such as not firm.
6.3 gap slag: concrete construction joints is bad, have stuff. Is mainly caused by careful cleaning.
6.4 irregular cracks: base is too long and contraction, lower concrete combining with bad, maintenance is not enough, or early to dismantle.
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 template elevation, the axis, the size of the preview.
7.3 structure with concrete should try apps and mix notice issued by the laboratory.
7.4 concrete block 28 d standard compressive strength test report. Commercial concrete shall have the factory certificate.
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