GBJ 82-1985 Test methods for long-term performance and durability of ordinary concrete
Some standard content:
Engineering Construction Standard Full-text Information System
National Standard of the People's Republic of China
Test Method for Long-term Performance and Durability of Ordinary Concrete
GBJ82-85
1985 Beijing
Engineering Construction Standard Full-text Information System
W Engineering Construction Standard Full-text Information System
National Standard of the People's Republic of China
Concrete Long-term Performance
Ordinary Concrete
And Durability Test Method
GBJ82-85
Editor Department: Urban and Rural Construction Environmental Protection Ministry of Construction Approval department: State Planning Commission of the People's Republic of China Effective date: July 1, 1986
Engineering Construction Standards Full Text Information System
Engineering Construction Standards Full Text Information System
Notice on the release of three national standards including "Test Methods for Performance of Ordinary Concrete Mixtures"
According to the requirements of the former National Construction Commission (78) Jianfa Shezi No. 562, the three standards including "Test Methods for Performance of Ordinary Concrete Mixtures" jointly compiled by the China Academy of Building Research of the Ministry of Urban and Rural Construction and relevant units have been reviewed by relevant departments. The three standards including "Test Methods for Performance of Ordinary Concrete Mixtures" GBJ8085, "Test Methods for Mechanical Properties of Ordinary Concrete" GBJ81-85 and "Test Methods for Long-term Performance and Durability of Ordinary Concrete" GBJ82-85 are now approved as national standards and will be implemented on July 1, 1986.
The three standards are managed by the Ministry of Urban and Rural Construction, and the specific interpretation and other work is the responsibility of the China Academy of Building Research. The publication and distribution is organized by the Institute of Basic Construction Standards and Norms of our Commission.
National Planning Commission
November 25, 1985
Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Preparation Instructions
This standard is prepared by the China Academy of Building Research in conjunction with relevant units in accordance with the requirements of the Notice No. 562 of the former State Construction Commission (78) Jianfashe. During the preparation process, a large amount of investigation, research and experimental demonstration work was carried out, and international standards and other relevant domestic and foreign standards and specifications were collected and referenced. After repeated discussions and revisions, the standards were formed. During the preparation process, the opinions of relevant units across the country were solicited many times, and finally the draft was reviewed and finalized with relevant departments.
This standard is the test method for long-term performance and durability of the basic properties of ordinary concrete. The content includes nine methods, including frost resistance test (slow freezing method, fast freezing method), dynamic elastic modulus test, impermeability test, shrinkage test, creep test under pressure, carbonization test, steel corrosion test in concrete, and compressive fatigue strength test. Since the long-term performance and durability test of ordinary concrete involves a wide range, and will continue to develop with the improvement of instruments and equipment and the improvement of testing technology, it is hoped that all units will pay attention to accumulating information and summarizing experience in the process of implementing this standard. If any modification or supplement is found, please send your opinions and relevant information to the Concrete Research Institute of China Academy of Building Research for reference in future modifications. Ministry of Urban and Rural Construction and Environmental Protection
July 1985
Engineering Construction Standards Full Text Information System
W Engineering Construction Standards Full Text Information System
Chapter 1
General Principles·
Chapter 2 Preparation and Maintenance of Test Pieces…
Chapter 3 Antifreeze Performance Test
Section 1 Slow Freezing Method
Section 2 Quick Freezing Method
Chapter 4
Dynamic Elastic Modulus Test
Chapter 5
Chapter 6
Chapter 7
Chapter 8
Chapter 9
Chapter 10
Impenetration Performance Test
Shrinkage Test
Compression Creep Test|| tt||Carbonation test
Reinforcement corrosion test in concrete
Compressive fatigue strength test
Appendix Explanation of terms used in this specification
Additional explanation
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Engineering Construction Standard Full Text Information System
Chapter 1 General
Article 1.0.1 This standard is formulated to provide a unified test method for long-term performance and durability of concrete when determining the characteristic values of concrete properties and inspecting or controlling the quality of cast-in-place concrete projects or prefabricated components. Article 1.0.2
This standard applies to the basic performance tests of ordinary concrete used in industrial and civil buildings and general structures. Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Chapter 2 Preparation and Maintenance of Test Pieces
Article 2.0.1 The test pieces for long-term performance and durability tests specified in this test method standard shall be in groups of three, except for the permeability and fatigue tests. The mixture used to prepare each group of long-term performance and durability test pieces and their corresponding comparisons shall be taken out from the concrete mixed in the same pan or transported by the same vehicle according to different requirements, or mixed separately in the laboratory by machine or manually. The grouping and sampling principles of test pieces used to inspect the quality of cast-in-place concrete engineering or prefabricated components shall be implemented in accordance with the current "Specifications for Construction and Acceptance of Reinforced Concrete Engineering" and other relevant regulations. Article 2.0.2 When preparing test pieces by mixing concrete in the laboratory, the amount of materials used shall be measured by weight, and the weighing accuracy shall be: cement, water and admixtures are all ±0.5%; aggregate is ±1%.
Article 2.0.3 All test specimens shall be made immediately after mixing or sampling. When determining the design characteristic value and grade of concrete or conducting material performance research, the molding method of the test specimen shall be determined according to the consistency of the concrete. Concrete with a drop of no more than 70 mm should be compacted by a vibration table, and concrete with a drop of more than 70 mm should be compacted manually by a tamping rod. For concrete used to inspect the quality of cast-in-place concrete projects and prefabricated components, the molding method of the test specimen shall be the same as the method used in actual construction.
Prismatic test specimens should be molded horizontally. When pouring concrete and tamping test specimens with embedded steel bars, special attention should be paid to ensuring that the concrete between the steel bars and the test mold can be kept dense and well compacted.
For concrete molded by special methods such as centrifugal method, grouting method, vacuum operation method and spraying method, the production of the test specimens shall be carried out in accordance with the corresponding regulations. Article 2.0.4 The test mold used to make the test specimen shall be made of cast iron or steel, shall have sufficient rigidity and be easy to disassemble and assemble. The inner surface of the test mold should be machined, and its unevenness should not exceed 0.05 mm per 100 mm. The non-verticality of each adjacent surface after assembly should not exceed ±0.5 degrees.
The test mold should be cleaned before making the test piece and should be coated with a release agent. Article 2.0.5, when using a vibration table for molding, the concrete mixture should be loaded into the test mold at one time. When loading, a spatula should be used to slightly insert and tamp along the inner wall of the test mold and the concrete mixture should be higher than the upper mouth of the test mold. The test mold should be prevented from jumping freely on the vibration table during vibration. The vibration should continue until the concrete surface is slurried, and the excess concrete is scraped off and smoothed with a spatula. The vibration frequency of the laboratory vibration table should be 50 ± 3 Hz, and the amplitude should be 0.5 mm when unloaded.
Article 2.0.6, when tamping manually, the concrete mixture should be loaded into the test mold in two layers, and the loading thickness of each layer should be roughly equal. The steel tamping rod used for tamping should be: 600 mm long, 16 mm in diameter, and the end should be rounded. The tamping should be carried out evenly from the edge to the center in a spiral direction. When tamping the bottom layer, the tamping rod should reach the bottom surface of the test mold; when tamping the upper layer, the tamping rod should penetrate the lower layer to a depth of about 20 to 30 mm. When tamping, the tamping rod should be kept vertical and should not be tilted. Use a spatula to insert it several times along the inner wall of the test mold. The number of tamping times for each layer should be determined according to the cross-section of the test piece, generally not less than 12 times for every 100 square centimeters of cross-sectional area. After tamping, scrape off the excess concrete and smooth it with a spatula. Article 2.0.Article 7 According to the specific provisions of each test method, the specimens for long-term performance and durability tests have standard curing, curing under the same conditions and natural curing. After the specimens are formed, the surface should be covered to prevent water evaporation, and they should be left to stand for one to two nights at a room temperature of 20 5 ℃, and then numbered and demolded. After demolding, the specimens should be immediately cured in a standard curing room with a temperature of 20 3 ℃ and a humidity of more than 90%. In the standard curing room, the specimens should be placed on a rack with a spacing of 10 to 20 mm between each other, and water should be avoided to directly rinse the specimens. When there is no standard curing room, concrete specimens can be cured in non-flowing water at 20 3 ℃. The pH value of water should not be less than 7.
Test specimens that are cured under the same conditions as the structure or component should be covered immediately after forming. The demoulding time of the test specimen can be the same as the demoulding time of the actual component. After demoulding, the test specimen still needs to be cured under the same conditions.
Test specimens that need to be placed naturally and dried should be placed in a dry and ventilated room, with at least 10 to 20 mm of space between each specimen. ||tt| ... Article 3.1.2 The slow freezing method concrete antifreeze performance test shall use cubic specimens. The size of the specimen shall be selected according to the maximum diameter of the aggregate in the concrete in accordance with Table 3.1.2-1.
Selection table of specimen sizes used in the slow freezing method
Specimen size
Inch (mm)
100×100×100
150×150×150
200×200×200
Table 3.1.2-1
Maximum diameter of aggregate (mm)
The number of specimen groups required for each test shall comply with the provisions of Table 3.1.2-2, and each group of specimens shall consist of 3 pieces.
Number of test specimens required for slow freezing test
Design antifreeze grade
Number of freeze-thaw cycles when checking strength
Number of test specimens required for 28-day strength assessment
Number of freeze-thaw test specimens
Number of comparison test specimens
Total number of test specimens
Engineering Construction Standard Full-text Information System
Table 3.1.2-2
Engineering Construction Standard Full-text Information System
Article 3.1.3 The equipment used for slow freezing concrete antifreeze performance test shall comply with the following provisions:
1. The freezing box (room) can keep the temperature in the box (room) within the range of -15 to -20°C after the test specimen is installed.
2. The melting water tank can keep the water temperature within the range of 15 to 20° after the test specimen is installed.
2. The frame basket is welded with steel bars, and its size should be adapted to the specimens installed. 4. The table scale weighs 10 kg and has a sensitivity of 5 grams. 5. The accuracy of the pressure testing machine is at least ±2%, and its range should be able to make the expected failure load value of the specimen not less than 20% of the full range and not more than 80% of the full range. Steel pads can be placed between the upper and lower pressure plates of the testing machine and the specimens, and both pressure-bearing surfaces of the steel pads should be machined.
The size of the pressure plate or pad in contact with the specimen should be larger than the pressure-bearing surface of the specimen, and its unevenness should not exceed 0.02 mm per 100 mm. Article 3.1.4 The slow freezing method concrete antifreeze performance test shall be carried out in accordance with the following provisions:
1. If there are no special requirements, the specimens shall be subjected to freeze-thaw tests at the age of 28 days. Four days before the test, the freeze-thaw specimens should be taken out of the curing site for appearance inspection, and then immersed in 15-20℃ water. The water surface should be at least 20 mm higher than the top surface of the specimens during immersion. The freeze-thaw test should be carried out after the freeze-thaw test specimens are immersed for 4 days. The comparison specimens should be kept in the standard curing room until the freeze-thaw cycle is completed, and then the pressure test is carried out at the same time as the antifreeze specimens. After the immersion is completed, the specimens are taken out, the surface moisture is wiped with a wet cloth, weighed, and placed in the frame basket according to the number, and then placed in the freezer (room) to start the freeze-thaw test. In the box (room), the frame basket should be vacant, and the contact between the specimen and the frame basket should be padded with pads, and at least 20 mm of space should be left. There should be at least 50 mm of space between the specimens in the frame basket. 3. The temperature during freezing in the antifreeze test should be maintained at -15-20℃. The specimens are placed in the box when the temperature reaches -20℃. If the temperature rises significantly after the specimens are installed, the freezing time will be calculated when the temperature drops back to -15℃. Each time from the completion of the test piece to the time of cooling down to -15℃ should not exceed 2 hours. The temperature in the freezer (room) shall be based on the temperature at its center.
4. The freezing time of the test piece in each cycle shall be determined according to its size. The freezing time for the 100×100×100 mm and 150×150×150 mm test pieces shall not be less than 4 hours, and the freezing time for the 200×200×200 mm test piece shall not be less than 6 hours. If the freezing test of test pieces of different specifications and sizes is carried out in the freezer (room) at the same time, the freezing time shall be calculated according to the test piece of the largest size. 5. After the freezing test, the test piece can be taken out and should be immediately placed in a water tank that can keep the water temperature at 15-20℃ for melting. At this time, the water level in the tank should be at least 20 mm higher than the surface of the test piece, and the time for the test piece to melt in the water should not be less than 4 hours. The freeze-thaw cycle ends when the thawing is completed. The specimen is taken out and sent to the freezer (room) for the next cycle test.
Sixth, the freeze-thaw specimens should be inspected visually frequently. If serious damage is found, the specimens should be weighed. If the average weight loss rate of the specimens exceeds 5%, the freeze-thaw cycle test can be stopped.
Seventh, after the concrete specimens reach the number of freeze-thaw cycles specified in Table 3.1.2-2, the compressive strength test should be carried out.
Before the compressive test, the specimens should be weighed and inspected visually, and the surface damage, cracks and corner defects of the specimens should be recorded in detail.
If the surface of the specimen is severely damaged, the test should be carried out after the plaster is leveled. Eighth, during the freeze-thaw process, if the test needs to be interrupted for some reason, in order to avoid water loss and affect the strength, the freeze-thaw specimens should be moved to the standard curing room for storage until the freeze-thaw test is resumed. At this time, the cause of the failure and the suspension time should be noted in the test results. Article 3.1.5 After the freeze-thaw test of concrete, its strength loss rate shall be calculated according to the following formula.
fo-fax100
...... (3.1..51)
△fc-Concrete strength loss rate after N freeze-thaw cycles, calculated by the average value of the three specimens:
(%);
fco-The average compressive strength of the comparison specimens (MPa); Engineering Construction Standard Full Text Information System
W.bzsoso.cOm3. The equipment used for the slow freezing method concrete antifreeze performance test shall comply with the following provisions:
1. The freezing box (room) can keep the temperature in the box (room) within the range of -15 to -20°C after the test piece is installed.
2. The melting water tank can keep the water temperature within the range of 15 to 20° after the test piece is installed.
2. The frame basket is welded with steel bars, and its size should be adapted to the test piece installed. 4. The table scale weighs 10 kg and has a sensitivity of 5 grams. 5. The accuracy of the pressure testing machine is at least ±2%, and its range should be able to make the expected failure load value of the test piece not less than 20% of the full range and not more than 80% of the full range. Steel pads can be placed between the upper and lower pressure plates of the testing machine and the test piece, and both pressure-bearing surfaces of the steel pads should be machined.
The size of the pressure plate or pad in contact with the specimen should be larger than the pressure-bearing surface of the specimen, and its unevenness should not exceed 0.02 mm per 100 mm. Article 3.1.4 The slow freezing method concrete antifreeze performance test shall be carried out in accordance with the following provisions:
1. If there is no special requirement, the specimen shall be subjected to freeze-thaw test at the age of 28 days. The freeze-thaw specimen shall be taken out from the curing site 4 days before the test, and the appearance shall be inspected. Then, it shall be immersed in 15-20℃ water. During immersion, the water surface shall be at least 20 mm higher than the top surface of the specimen. The freeze-thaw test shall be carried out after the freeze-thaw specimen is immersed for 4 days. The comparison specimen shall be kept in the standard curing room until the freeze-thaw cycle is completed, and then the pressure test shall be carried out at the same time as the antifreeze specimen. After immersion, take out the specimen, wipe the surface moisture with a wet cloth, weigh it, put it into the frame basket according to the number, and then put it into the freezer (chamber) to start the freeze-thaw test. In the box (room), the frame basket should be suspended, and the contact between the test piece and the frame basket should be padded with pads, and at least 20 mm of space should be left. There should be at least 50 mm of space between each test piece in the frame basket. 3. The temperature should be kept at -15-20℃ during the antifreeze test. The test piece is put in when the temperature in the box reaches -20℃. If the temperature rises significantly after the test piece is installed, the freezing time is calculated when the temperature drops to -15℃ again. The time required from the completion of the test piece to the return to -15℃ should not exceed 2 hours each time. The temperature in the freezer (room) shall be based on the temperature at its center.
Fourth, the freezing time of the specimen in each cycle shall be determined according to its size. The freezing time for the 100×100×100 mm and 150×150×150 mm specimens shall not be less than 4 hours, and the freezing time for the 200×200×200 mm specimens shall not be less than 6 hours. If the freezing test of specimens of different specifications and sizes is carried out in the freezer (room) at the same time, the freezing time shall be calculated according to the specimen of the largest size. Five, after the freezing test is completed, the specimen can be taken out and immediately placed in a water tank that can keep the water temperature at 15-20°C for thawing. At this time, the water level in the tank should be at least 20 mm higher than the surface of the specimen, and the time for the specimen to melt in the water should not be less than 4 hours. The freezing and thawing cycle is over when the thawing is completed, and the specimen is taken out and sent to the freezer (room) for the next cycle test.
Six, the appearance of the frozen and thawed specimens should be checked frequently. If serious damage is found, it should be weighed. If the average weight loss rate of the specimen exceeds 5%, the freezing and thawing cycle test can be stopped.
VII. After the concrete specimen reaches the number of freeze-thaw cycles specified in Table 3.1.2-2, a compressive strength test should be carried out.
Before the compressive test, the specimen should be weighed and inspected for appearance, and detailed records should be kept of surface damage, cracks and corner defects of the specimen.
If the surface of the specimen is severely damaged, it should be leveled with gypsum before the pressure test. VIII. During the freeze-thaw process, if the test needs to be interrupted for some reason, in order to avoid water loss and affect the strength, the freeze-thaw specimen should be moved to a standard curing room for storage until the freeze-thaw test is resumed. At this time, the cause of the failure and the suspension time should be noted in the test results. Article 3.1.5 After the freeze-thaw test of concrete, its strength loss rate should be calculated according to the following formula.
fo-fax100
...... (3.1..51)
△fc-Concrete strength loss rate after N freeze-thaw cycles, calculated based on the average value of the three specimens:
(%);
fco-The average compressive strength of the comparison specimens (MPa); Engineering Construction Standard Full Text Information SystembzxZ.net
W.bzsoso.cOm3. The equipment used for the slow freezing method concrete antifreeze performance test shall comply with the following provisions:
1. The freezing box (room) can keep the temperature in the box (room) within the range of -15 to -20°C after the test piece is installed.
2. The melting water tank can keep the water temperature within the range of 15 to 20° after the test piece is installed.
2. The frame basket is welded with steel bars, and its size should be adapted to the test piece installed. 4. The table scale weighs 10 kg and has a sensitivity of 5 grams. 5. The accuracy of the pressure testing machine is at least ±2%, and its range should be able to make the expected failure load value of the test piece not less than 20% of the full range and not more than 80% of the full range. Steel pads can be placed between the upper and lower pressure plates of the testing machine and the test piece, and both pressure-bearing surfaces of the steel pads should be machined.
The size of the pressure plate or pad in contact with the specimen should be larger than the pressure-bearing surface of the specimen, and its unevenness should not exceed 0.02 mm per 100 mm. Article 3.1.4 The slow freezing method concrete antifreeze performance test shall be carried out in accordance with the following provisions:
1. If there is no special requirement, the specimen shall be subjected to freeze-thaw test at the age of 28 days. The freeze-thaw specimen shall be taken out from the curing site 4 days before the test, and the appearance shall be inspected. Then, it shall be immersed in 15-20℃ water. During immersion, the water surface shall be at least 20 mm higher than the top surface of the specimen. The freeze-thaw test shall be carried out after the freeze-thaw specimen is immersed for 4 days. The comparison specimen shall be kept in the standard curing room until the freeze-thaw cycle is completed, and then the pressure test shall be carried out at the same time as the antifreeze specimen. After immersion, take out the specimen, wipe the surface moisture with a wet cloth, weigh it, put it into the frame basket according to the number, and then put it into the freezer (chamber) to start the freeze-thaw test. In the box (room), the frame basket should be suspended, and the contact between the test piece and the frame basket should be padded with pads, and at least 20 mm of space should be left. There should be at least 50 mm of space between each test piece in the frame basket. 3. The temperature should be kept at -15-20℃ during the antifreeze test. The test piece is put in when the temperature in the box reaches -20℃. If the temperature rises significantly after the test piece is installed, the freezing time is calculated when the temperature drops to -15℃ again. The time required from the completion of the test piece to the return to -15℃ should not exceed 2 hours each time. The temperature in the freezer (room) shall be based on the temperature at its center.
Fourth, the freezing time of the specimen in each cycle shall be determined according to its size. The freezing time for the 100×100×100 mm and 150×150×150 mm specimens shall not be less than 4 hours, and the freezing time for the 200×200×200 mm specimens shall not be less than 6 hours. If the freezing test of specimens of different specifications and sizes is carried out in the freezer (room) at the same time, the freezing time shall be calculated according to the specimen of the largest size. Five, after the freezing test is completed, the specimen can be taken out and immediately placed in a water tank that can keep the water temperature at 15-20°C for thawing. At this time, the water level in the tank should be at least 20 mm higher than the surface of the specimen, and the time for the specimen to melt in the water should not be less than 4 hours. The freezing and thawing cycle is over when the thawing is completed, and the specimen is taken out and sent to the freezer (room) for the next cycle test.
Six, the appearance of the frozen and thawed specimens should be checked frequently. If serious damage is found, it should be weighed. If the average weight loss rate of the specimen exceeds 5%, the freezing and thawing cycle test can be stopped.
VII. After the concrete specimen reaches the number of freeze-thaw cycles specified in Table 3.1.2-2, a compressive strength test should be carried out.
Before the compressive test, the specimen should be weighed and inspected for appearance, and detailed records should be kept of surface damage, cracks and corner defects of the specimen.
If the surface of the specimen is severely damaged, it should be leveled with gypsum before the pressure test. VIII. During the freeze-thaw process, if the test needs to be interrupted for some reason, in order to avoid water loss and affect the strength, the freeze-thaw specimen should be moved to a standard curing room for storage until the freeze-thaw test is resumed. At this time, the cause of the failure and the suspension time should be noted in the test results. Article 3.1.5 After the freeze-thaw test of concrete, its strength loss rate should be calculated according to the following formula.
fo-fax100
...... (3.1..51)
△fc-Concrete strength loss rate after N freeze-thaw cycles, calculated based on the average value of the three specimens:
(%);
fco-The average compressive strength of the comparison specimens (MPa); Engineering Construction Standard Full Text Information System
W.bzsoso.cOm
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