1. Provisions on sampling of cement witnesses
According to the standard:
"General Portland Cement" (National Standard No. 1 Amendment Order) GB 175-2007/XG1-2009 (implemented on September 01, 2009, currently valid);
The naming, definition and terminology of cement GB/T 4131-2014 (implemented on 2015.02.01, currently in force);
Cement sampling method GB12573-2008 (implemented on August 1, 2008, currently valid)
1． Cement sampling and sending rules
1) First of all, it is necessary to know whether the production plant of the purchased cement has a product production license.
2) Cement commissioned inspection samples must be sampled by each factory cement number as a sampling unit, and there must be no mixed sampling of more than two factory numbers.
3) Cement specimens must be collected in equal amounts at different parts of the same number, the sampling point is at least 20 points or more, and after mixing evenly, it is packaged in a moisture-proof container, and the weight is not less than 12kg.
4) The entrusting unit must fill in the inspection commission form one by one, such as the name of the cement production plant, trademark, cement variety, strength grade, factory number or factory date, project name, a full set of physical inspection items, etc. Cement used for decoration should be tested for stability.
5) Cement delivery date of more than three months should be re-inspected before it is used.
6) Imported cement shall be carried out in accordance with the above requirements.
2． Cement sampling regulations
1) Before leaving the factory, the cement is numbered and sampled according to the same variety and strength grade. Bagged cement and bulk cement should be numbered and sampled separately. Each number is a sampling unit. The cement factory number is specified according to the annual production capacity:
A, 200 × 104t or more, not more than 4000t for a number;
B, 120× 104t ~ 200× 104t, not more than 2400t for a number;
C, 60× 104t ~ 120× 104t, not more than 1000t for a number;
D, 30× 104t ~ 60× 104t, not more than 600t for a number;
E, 10× 104t ~ 30× 104t, not more than 400t for a number;
F, 10× 104t or less, not more than 200t for a number.
When the capacity of bulk cement transport exceeds the factory number of tons specified by the plant, the number of the number is allowed to exceed the number of tons specified for sampling.
2) When there is doubt about the quality of cement in use or the cement leaves the factory for more than three months (fast hard Portland cement for more than one month), it should be re-inspected and used according to the re-inspection results.
Note: Cement sampling needs to be attached with the corresponding cement factory certificate
2. Sampling regulations for sand and stone
Construction pebbles, gravel GB/T 14685-2011 (2012.02.01 implementation, currently valid);
Construction sand GB/T 14684-2011 (implemented on 2012.02.01, currently valid)
1) If the sand and stone are transported by large tools, 400m3 or 600t is used as an acceptance batch. Transported with small tools, 200 m3 or 300 t for a acceptance batch. Less than the above number can be a batch of arguments. When the sand and gravel quality is relatively stable and the feed volume is large, 1000t can be used as an acceptance batch.
2) When sampling in the pile, the sampling site should be evenly distributed. The surface layer of the sample site is removed before sampling. Then, for the sand, 8 parts of the sand are extracted from each part to form a set of samples. For the stones, 15 parts of roughly equal parts were extracted from each part (taken from five different parts evenly distributed at the top, middle and bottom of the pile) to form a set of samples. (Stone: 100Kg, Sand: 50Kg)
3) If the inspection is unqualified, it should be re-sampled. For nonconformances, double re-inspection. If there is still a specimen that cannot meet the requirements of the standard, it should be treated as a non-conforming product.
3. Basic backfill sampling regulations
Geotechnical test method standard (2007 edition) GB/T 50123-1999 (2007 edition) (implemented on October 1, 1999, currently valid);
Highway Engineering Quality Inspection and Evaluation Standards Vol.1 Civil Engineering JTG F80/1-2004 (implemented on January 1, 2005, currently in force)
Construction Note: Highway Engineering Quality Inspection and Evaluation Standards Vol. 1 Civil Engineering JTG F80/1-2017, to be implemented on May 1, 2018.
1． Before backfilling, the backfill material should be taken on the spot for a solid test, and the soil sample taken should be representative. (Clay: 30kg; gravel and graded sandstone: 50kg)
2． The amount of density sampled should meet the following requirements.
A. Site leveling: each floor takes 1 group of 100m2~400m2;
B. Separate foundation pit: 20 m2 ~ 50 m2 to take a group, and not less than 1 group;
C. Indoor backfilling: ditch and foundation, each layer 20 m2 ~ 50 m2 to take a group;
D. Take 1 group of other 50 m2~200 m2.
Fourth, the provisions on sampling of steel raw materials
Carbon structural steel GB/T 700-2006 (implemented on 2007.02.01, currently valid);
Mild steel hot-rolled disc strip GB/T701-2008 (implemented on April 1, 2009, currently valid);
Steel for reinforced concrete (Part 1) Hot-rolled light round rebar National Standard No. 1 Modified Single GB 1499.1-2008/XG1-2012 (implemented on 2013.01.01, currently in force);
Steel for reinforced concrete (Part 2) Hot-rolled ribbed steel reinforcement (National Standard No. 1 Amendment Order) GB1499.2-2007/XG1-2009 (implemented on 2009.09.01, currently valid)
Steel for reinforced concrete (Part 1) Hot-rolled light round steel reinforcement National Standard No. 1 modified single GB 1499.1-2008/XG1-2017, which will be implemented on September 1, 2018.
Steel for reinforced concrete (Part 2) hot-rolled ribbed steel bar GB 1499.2-2018 will be implemented on November 1, 2018.
Raw material sampling rules:
1) Hot-rolled glossy round steel and residual heat treatment rebar are composed of steel bars of the same grade, the same furnace tank number, the same specification and the same delivery state with a weight of not more than 60t.
2) Hot-rolled ribbed steel bars and low-carbon steel hot-rolled disc strips are composed of the same grade, the same furnace tank number and the same specification of steel bars with a weight of not more than 60t.
3) Each batch of carbon structural steel is composed of the same grade, the same furnace and tank number, the same grade, the same variety, the same size, and the same delivery state of the steel bar weighing no more than 60t.
4) Each batch of cold-rolled ribbed steel bars is composed of steel bars of the same grade, the same shape, the same specifications, the same production process and the same delivery state, and each batch is not more than 60t.
5) Section steel should be inspected and accepted according to the batch, and the weight of each batch shall not be greater than 60t. Each batch should consist of the same grade, the same furnace and tank number, the same grade, the same variety, the same size, and the same delivery status.
2． Quantity of raw material samples (The number of specimens for rebar varies depending on the form of supply.) ）
1) Straight bar rebar: Each batch of straight bar rebar should do 2 tensile tests and 2 bending tests. Each batch of straight steel bars accepted with "Carbon Structural Steel" (GB/T 700-2006) should have 1 tensile test and 1 bending test.
2) Cold-rolled ribbed steel reinforcement: 1 tensile test per plate or bundle by bundle, 2 bending tests per batch of CRB550 grade, and 2 repeated bending tests per batch of CRB650 and above.
4) Section steel: Each batch of section steel should do 1 tensile test and 1 bending test. （GB/T 700-2006）
3． Sampling method
Specimens for tensile and bending tests can be cut from two bars per batch of material. Rebar specimens do not require any processing.
Note: The number and length of samples are detailed in Table 1
In addition: the raw material weight deviation sampling requirements are taken from different steel bars, the number is not less than 5, the length of each specimen is not less than 500mm, and the length should be measured branch by branch, accurate to 1mm. When measuring the total weight of the specimen, it should be accurate to no greater than 1% of the total weight.
Five. Specifications for sampling of reinforcement weldments
Cylindrical head welding nails for arc stud welding GB/T 10433-2002 (implemented on June 01, 2003, currently valid);
Reinforcement welding and acceptance procedures JGJ 18-2012 (implemented on August 1, 2012, currently in force);
Standard for test methods for welded joints in steel reinforcement JGJ/T 27-2014 (implemented on December 1, 2014, currently valid)
1) 1． Flash butt welding
2) When the mechanical properties are tested, 6 joints should be randomly cut from each batch of joints, of which 3 are used for tensile test and 3 are bent tests.
3) In the same class, 300 steel welding joints of the same level and diameter completed by the same welder should be used as a batch. When the number of welded joints in the same class is small, it can be cumulatively calculated within one week; the cumulative number of joints is still less than 300, which should be calculated as a batch.
4) Closed ring stirrup flash pair welding head, with 600 joints of the same grade and specifications as a batch, only for tensile testing
5) 2． arc welding
6) In the cast-in-place concrete structure, 300 steel bars of the same grade and the same type joint should be used as a batch; in the house structure, 300 steel bars of the same grade and the same type joint should be used as a batch in no more than two floors. Each batch of 3 joints was randomly cut for tensile testing.
7) In the prefabricated structure, simulated specimens can be made according to the production conditions, each batch of 3, and tensile tests can be done.
3． Electroslag pressure welding
In cast-in-place reinforced concrete structures, 300 rebar joints of the same grade should be used as a batch; in the structure of the house, 300 rebar joints of the same grade should be used as a batch on no more than two floors; when there are less than 300 joints, it should still be used as a batch. Each batch of 3 joints is randomly cut for tensile testing.
4． Embedded reinforcement T-joint
1) When the mechanical properties test is carried out, 300 embedded parts of the same type should be used as a batch. When welding continuously within one week, it can be calculated cumulatively. When there are less than 300 pieces, it is also calculated as a batch.
2) 3 joints should be randomly cut from each batch of embedded parts for tensile testing, the length of the steel bar of the specimen should be greater than or equal to 200mm (200mm on one side, 400mm on both sides), and the length and width of the steel plate should be greater than or equal to 60mm.
Sixth, mechanical connection joint sampling regulations
Technical Regulation for Mechanical Connection of Reinforcement JGJ 107-2016 (implemented on August 01, 2016, currently in force);
Sleeve for mechanical connection of rebar JG/T 163-2013 (implemented on October 1, 2013, currently valid)
1. The on-site sampling inspection of the joint should include the ultimate tensile strength test, processing and installation quality inspection. Sampling inspection should be carried out according to the inspection batch, the same steel production plant, the same strength grade, the same specification, the same type and the same type of joints should be 500 for one acceptance batch for inspection and acceptance, less than 500 should also be used as an inspection batch.
Under the same construction conditions, the same grade and same type of the same specification joints of the same material are used to inspect and accept 500 continuously produced as an inspection batch, and less than 500 are also calculated according to one inspection batch. Take 3 for tensile testing.
2. Continuous inspection of 10 inspection batches on the spot, when all its one-way stretching specimens are sampled at one time, the number of inspection batch joints can be expanded to 1000.
Note: When entrusting, it is necessary to provide the corresponding "Type Test Report" and indicate the joint level (see Table 1 for details of the specific sampling length)
7. Sampling regulations for ordinary concrete specimens
Ready-mixed concrete GB/T 14902-2012 (implemented on September 01, 2013, currently valid);
Ordinary concrete mixture performance test method standard GB/T 50080-2016 (2017.04.01 implementation, currently valid)
Concrete structure engineering construction quality acceptance specification GB50204-2015 (2015.09.01 implementation, currently valid)
Standard GB/T50082-2009 (implemented on 2010.07.01, currently valid)
Standard GB/T 50081-2002 (implemented on June 01, 2003, currently valid)
The following is excerpted from the concrete structure engineering construction quality acceptance code GB50204-2015
Ready-mixed (commodity) concrete
The following is an excerpt from GBT 14902-2012 ready-mixed concrete
Fly ash concrete
The quality of fly ash concrete should be tested by slump degree and compressive strength.
The inspection of the slump of fly ash concrete for on-site construction should be measured at least twice per shift, and the allowable deviation of the measured value is ±20mm.
For non-large volume fly ash concrete per mix of 100 m3, at least one set of test blocks is formed; for large volume fly ash concrete per mix of 500 m3, at least one set of test blocks is formed. When the number specified above is insufficient, at least one set of test blocks will be formed per shift.
VIII. Provisions on sampling of masonry materials
Light aggregate concrete small hollow block GB/T 15229-2011 (implemented on August 01, 2012, currently valid);
Autoclaved lime sand brick GB 11945-1999 (implemented on 2000.02.01, currently valid);
Ordinary concrete small hollow block GB/T 8239-2014 (implemented on December 1, 2014, currently valid);
Sintered porous bricks and porous blocks GB 13544-2011 (implemented on April 1, 2012, currently in force);
Sintered ordinary brick GB 5101-2003 (implemented on April 1, 2004, currently valid);
Test method for building wall tiles GB/T 2542-2012 (implemented on September 1, 2013, currently valid);
Concrete small hollow block test method GB/T4111-2013 (implemented on September 1, 2014, currently valid);
Autoclaved aerated concrete block GB11968-2006 (implemented on December 1, 2006, currently valid);
Sintered hollow bricks and hollow blocks GB 13545-2014 (implemented on 2015.02.01, currently valid)
1. Sintered hollow bricks and hollow blocks: 35,000-150,000 pieces are a batch, and less than 35,000 are counted as a batch.
Number of samples: intensity: 10 pieces; density: 5 pieces;
2. Autoclaved lime sand bricks: the same type of lime sand bricks are a batch for every 100,000 pieces, and less than 100,000 pieces are also a batch.
Number of samples: Strength: 10 pieces;
3. Small hollow block of light aggregate concrete: the block is accepted in batches according to the density and strength level. A batch of 10,000 blocks made of the same density, the same strength grade, quality grade and the same production process made of the same variety of light aggregates is a batch; the number of blocks produced per month is less than 10,000 blocks.
Number of samples: strength: 5 pieces; density, moisture content, water absorption and relative moisture content: 3 pieces; dry shrinkage rate: 3 pieces; frost resistance: 10 pieces;
4. Ordinary concrete small hollow block: batch acceptance according to appearance quality and strength level. A batch of 10,000 blocks produced with the same appearance quality grade, strength grade and the same process formulated from the same raw material is also a batch, and the number of blocks produced per month is less than 10,000 blocks.
Number of samples: strength level: 5 pieces; relative moisture content, impermeability, hollow rate: 3 pieces each; frost resistance: 10 pieces
5, fly ash bricks: every 100,000 pieces for a batch, less than 100,000 pieces are counted as a batch.
Sampling quantity: chromatic aberration: 36 pieces; strength grade: 10 pieces; frost resistance: 10 pieces; dry shrinkage: 3 pieces;
Carbonization performance: 15 pieces
6, concrete porous bricks: according to the appearance and quality and other grades and strength grades in batches of acceptance. 35,000-150,000 concrete porous bricks with the same appearance quality and strength level produced by the same raw materials and produced by the same process are counted as a batch, and less than 35,000 pieces are counted as a batch.
Number of samples: strength grade: 10 pieces; dry shrinkage, relative moisture content, impermeability, radioactivity: 3 pieces each; frost resistance: 10 pieces
7. Sintered porous bricks: 35,000-150,000 pieces for a batch, less than 35,000 pieces are counted as a batch.
Number of samples: strength level: 10 pieces; hole type porosity and hole arrangement, frost, lime bursting, water absorption and saturation coefficient, freeze-thaw: 5 pieces each
8. Sintered ordinary bricks: 35,000-150,000 pieces are a batch, and less than 35,000 pieces are counted as a batch.
Number of samples: intensity level: 10 pieces; frost, lime bursting, water absorption and saturation coefficient, freeze-thaw: 5 pieces each; radioactive: 4 pieces
9. Provisions on sampling of mortar test blocks
Standard JGJ 70-2009 (implemented on June 1, 2009, currently valid);
Cementitious grouting material JC/T986-2005 (implemented on August 1, 2005, currently valid)
1. Each inspection batch and not more than 250m3 of various types and strength levels of masonry mortar, each mixer at least once sampled, each group of 6 pieces.
2, the building ground engineering according to each floor should not be less than a group, when each floor of the building ground engineering area of more than 1000m2 to increase a group, less than 1000 m2, according to 1000 m2, when the mix ratio is not the same time should be corresponding to the production of different specimens.
Remarks: Mortar sampling should be representative and random, the maintenance methods are standard maintenance, and the number of specimen groups for an acceptance batch is not less than 3 groups in principle
10. Provisions on sampling of admixtures
Mineral admixture for high-strength and high-performance concrete GB/T 18736-2017 (implemented on 2018.02.01, currently valid);
Concrete admixture GB 8076-2008 (implemented on December 30, 2009, currently valid);
Concrete admixture homogeneousness test method GB/T 8077-2012 (implemented on August 1, 2013, currently valid);
Technical specification for the application of concrete admixtures GB 50119-2013 (implemented on 2014.03.01, currently valid);
Definition, classification, naming and terminology of concrete admixtures GB/T8075-2005 (implemented on August 01, 2005, currently valid);
Concrete expander GB23439-2009 (implemented on March 1, 2010, currently valid);
Concrete admixture term GB/T8075-2017 will be implemented on November 1, 2018.
Concrete expander GB23439-2017 will be implemented on November 1, 2018.
Mortar and concrete waterproofing agent JC 474-2008 (implemented on December 1, 2008, currently valid)
1, the same manufacturer, the same variety of a supply of 50t for a batch, less than 50t according to a batch, take no less than 0.2t cement required for the additional dose, the same batch number of products must be mixed evenly.
2, waterproof agent, pumping agent The same manufacturer, the same variety of a supply of 10t for a batch, less than 10t according to a batch, take no less than 0.2t cement required for the additional dose, the same batch number of products must be mixed evenly.
3, water reducer, early strength agent, retarder, inhalant The same manufacturer, the same variety of a supply of 10t for a batch, less than 10t according to a batch, not less than 0.2t cement required for the additional dose, the same batch number of products must be mixed evenly.
Note: When entrusting the admixture, the factory certificate of conformity must be attached
11. Provisions on fly ash sampling
Fly ash for cement and concrete GB/T 1596-2005 (implemented on August 01, 2005, currently in force)
Fly ash is supplied continuously in the same grade of 200t as a batch of 8 kg per sample. A factory certificate of conformity is required.
Bean Ding Construction Note: Fly ash FOR cement and concrete GB/T 1596-2017, to be implemented on June 1, 2018.
XII. Provisions on sampling of waterproof materials
Asphalt waterproofing membrane test method GB/T328-2007 (2007.10.01 implementation, currently valid)
Waterproofing membrane The coil of the same variety, grade and specification grade of the product, the sampling quantity is greater than 1000 rolls to extract 5 volumes, 500 to 1000 rolls to extract 4 volumes, 100 to 499 volumes to extract 3 volumes, less than 100 volumes to extract 2 volumes Each batch of sampling volumes takes 1m long as a sample
Waterproof coatings The same specification, the same variety, the same manufacturer for every 10T for a batch, less than 10T also according to a batch to take 2kg, internal and external wall aqueous solution coatings the same manufacturer, the same variety, the same batch to take 2kg.