GB/T 50266: Evolution and historical versions
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| GB/T 50266-2013 | English | RFQ |
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7 days [Need to translate]
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Standard for test methods of engineering rock mass
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GB/T 50266-2013
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| GB/T 50266-1999 | English | RFQ |
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14 days [Need to translate]
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Standard for tests method of engineering rock massas
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GB/T 50266-1999
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PDF similar to GB/T 50266-2013
Basic data | Standard ID | GB/T 50266-2013 (GB/T50266-2013) | | Description (Translated English) | Standard for test methods of engineering rock mass | | Sector / Industry | National Standard (Recommended) | | Classification of Chinese Standard | P13 | | Classification of International Standard | 93.020 | | Word Count Estimation | 129,141 | | Older Standard (superseded by this standard) | GB/T 50266-1999 | | Quoted Standard | GB/T 50123 | | Regulation (derived from) | Announcement of the Ministry of Housing and Urban No. 1633 | | Issuing agency(ies) | Ministry of Housing and Urban-Rural Development of the People's Republic of China; General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China | | Summary | This standard applies to: foundations, rock, slope and filling materials rock engineering test. | GB/T 50266-2013: Standard for test methods of engineering rock mass---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
1 General
1.0.1 This standard is formulated for the purpose of unifying engineering rock test methods, improving the quality of test results, and enhancing the comparability of test results.
1.0.2 This standard applies to engineering rock mass tests for foundations, surrounding rock, slopes and filling materials.
1.0.3 The engineering rock test object should be geologically representative. The test content, test methods, technical conditions, etc. shall comply with the basic requirements and characteristics of engineering construction survey, design, construction, and quality inspection.
1.0.4 In addition to conforming to this standard, the engineering rock mass test shall conform to the current relevant national standards.
2 Rock test
2.1 Moisture content test
2.1.1 All kinds of rock moisture content tests shall adopt the drying method.
2.1.2 Rock specimens shall meet the following requirements.
1 The samples with natural moisture content shall be taken on site, and the blasting method shall not be used. During the process of collection, transportation, storage and preparation of test specimens, the samples should be kept in a natural water state. When the water content needs to be measured in other tests, the test pieces after the test can be used for preparation.
2 The minimum size of the test piece should be greater than 10 times the diameter of the largest mineral particle of the constituent rock, the mass of each test piece should be 40g~200g, and the number of test pieces in each group should be 5.
3 When measuring the moisture content of the structural surface filling, it should comply with the relevant provisions of the current national standard "Standards for Geotechnical Test Methods" GB/T 50123.
2.1.3 The description of the test piece should include the following contents.
1 Rock name, color, mineral composition, structure, structure, degree of weathering, properties of cement, etc.
2 Measures taken to maintain the hydrated state.
2.1.4 It should include the following main instruments and equipment.
1 Oven and dryer.
2 scales.
2.1.5 The test should be carried out according to the following steps.
1 The mass of the test piece before drying shall be weighed.
2 The test piece should be placed in an oven and baked at a temperature of 105°C to 110°C for 24 hours.
3 Take the test piece out of the oven, put it in a desiccator to cool down to room temperature, and weigh the mass of the test piece after drying.
4 Weighing should be accurate to 0.01g.
2.1.6 The arrangement of test results shall meet the following requirements.
1 The water content of rock shall be calculated according to the following formula.
In the formula.
w—rock water content (%);
mo - the mass of the test piece before drying (g);
ms—the mass of the sample after drying (g).
2 Calculated values should be accurate to 0.01.
2.1.7 The rock water content test records shall include the name of the project, the number of the test piece, the description of the test piece, and the quality of the test piece before and after drying.
2.2 Particle density test
2.2.1 The density test of rock particles shall adopt the pycnometer method or the weighing method in water. The pycnometer method can be used for all kinds of rocks, and the underwater weighing method should comply with the provisions of Section 2.4 of this standard.
2.2.2 The fabrication of rock specimens shall meet the following requirements.
1 The rock should be crushed into rock powder with a crusher, so that all of it passes through the 0.25mm sieve, and the iron filings should be absorbed by a magnet.
2 For rocks containing magnetic minerals, they should be crushed with a porcelain mortar or agate mortar so that all of them pass through a 0.25mm sieve.
2.2.3 The description of the test piece should include the following contents.
1 The name, color, mineral composition, structure, structure, degree of weathering, properties of cement, etc. of the rock before crushing.
2 methods of crushing rocks.
2.2.4 The following main instruments and equipment should be included.
1 Pulverizer, porcelain mortar or agate mortar, magnet block and sieve with an aperture of 0.25mm.
2 scales.
3 Ovens and dryers.
4 Boiling equipment and vacuum extraction equipment.
5 constant temperature water tank.
6 Short neck pycnometer. volume 100mL.
7 Thermometer. range 0℃～50℃, minimum scale value 0.5℃.
2.2.5 The test should be carried out according to the following steps.
1 The prepared rock powder should be dried at a temperature of 105°C to 110°C, and the drying time should not be less than 6 hours, and then placed in a desiccator to cool to room temperature.
2 Use the quartering method to take two parts of rock powder, and the quality of each part of rock powder should be 15g.
3 The rock powder should be put into the dry pycnometer, and the test solution (distilled water or kerosene) should be injected to half the volume of the pycnometer. For rocks containing water-soluble minerals, kerosene should be used as the test solution.
4 When distilled water is used as the test solution, the gas can be removed by boiling or vacuum pumping. When kerosene is used as the test solution, the gas should be removed by vacuum pumping method.
5 When using the boiling method to remove gas, the boiling time should not be less than 1 hour after heating and boiling.
6 When the vacuum pumping method is used to remove gas, the reading of the vacuum pressure gauge should be the local atmospheric pressure. When pumping until no bubbles escape, the pumping time should not be less than 1h.
7.The test solution that has been degassed should be injected into the pycnometer until it is nearly full, and then placed in a constant temperature water tank. The temperature in the bottle should be kept constant and the upper suspension should be clarified.
8.The cork should be put on the bottle so that the excess test solution overflows from the capillary pores of the cork, and the outside of the bottle should be wiped dry. The total mass of the bottle, test solution and rock powder should be weighed, and the temperature of the test solution in the bottle should be measured.
9 The pycnometer should be cleaned, and the test solution that has been degassed and at the same temperature as the test should be injected into the pycnometer, and the quality of the bottle and the test solution should be weighed according to the steps in paragraphs 7 and 8 of this article.
10 Weighing should be accurate to 0.001g, and temperature should be accurate to 0.5°C.
2.2.6 The arrangement of test results shall meet the following requirements.
1 The rock particle density shall be calculated according to the following formula.
In the formula.
ρs—rock particle density (g/cm3);
ms—mass of dried rock powder (g);
m1——the total mass of bottle and test solution (g);
m2——the total mass of bottle, test solution and rock powder (g);
ρwt—the density of the test solution at the same temperature as the test temperature (g/cm3).
2 Calculated values should be accurate to 0.01.
3 The particle density test should be measured twice in parallel, the difference between the two measurements should not be greater than 0.02, and the particle density should be the average value of the two measurements.
2.2.7 The rock particle density test records shall include project name, test piece number, test piece description, pycnometer number, test solution temperature, test solution density, dry rock powder mass, total mass of bottle and test solution, and bottle, test solution and the total mass of rock dust.
2.3 Block density test
2.3.1 The volumetric method, weighing method in water or wax sealing method may be used for the density test of rock blocks, and shall meet the following requirements.
1 For all kinds of rocks that can be prepared into regular specimens, the volumetric method should be adopted.
2 Except for rocks that disintegrate, dissolve, shrink and swell when exposed to water, the weighing method in water can be used. The water weighing method test shall comply with the provisions of Section 2.4 of this standard.
3 For rocks that cannot be measured by the volumetric method or weighing method in water, the wax sealing method should be used.
4 The water used in this standard is clean water, and the density of water is taken as 1g/cm3.
2.3.2 Rock specimens by volumetric method shall meet the following requirements.
1 The size of the specimen should be greater than 10 times the diameter of the largest mineral particle in the rock, and the minimum size should not be less than 50mm.
2 The test piece can be cylinder, square cylinder or cube.
3 The error along the height, diameter or side length of the test piece should not be greater than 0.3mm.
4 The non-parallelism error of both ends of the test piece should not be greater than 0.05mm.
5 The end face of the test piece should be perpendicular to the axis of the test piece, and the maximum deviation should not be greater than 0.25°.
6 Adjacent sides of a square column or cube should be perpendicular to each other, and the maximum deviation should not be greater than 0.25°.
2.3.3 The wax-sealing test piece should be a round rock block with a side length of 40mm to 60mm.
2.3.4 The number of test specimens in each group should be 5 for wet density and 3 for dry density.
2.3.5 The description of the test piece should include the following.
1 Rock name, color, mineral composition, structure, structure, degree of weathering, properties of cement, etc.
2.Development degree and distribution of joint fissures.
3 The shape of the test piece.
2.3.6 It should include the following main instruments and equipment.
1 Diamond machines, stone cutters, stone grinders and grinders, etc.
2 Ovens and dryers.
3 scales.
4 Measuring platform.
5 Wax melting equipment.
6 Weighing device in water.
7 Vernier calipers.
2.3.7 The volumetric test should be carried out according to the following steps.
1 The two diameters or side lengths perpendicular to each other on the two ends and the middle three sections of the test piece shall be measured, and the cross-sectional area shall be calculated according to the average value.
2 The heights of the four symmetrical points around the two ends and the five heights of the central point shall be measured, and the average height shall be calculated.
3 The test piece should be placed in an oven, baked at a temperature of 105°C to 110°C for 24 hours, taken out and placed in a desiccator to cool to room temperature, and the mass of the dried test piece should be weighed.
4 The length measurement should be accurate to 0.02mm, and the weighing should be accurate to 0.01g.
2.3.8 The wax seal method test should be carried out according to the following steps.
1 When measuring the wet density, a representative rock should be taken to prepare a test piece and weighed; when measuring the dry density, the test piece should be baked at a temperature of 105°C to 110°C for 24 hours, taken out and placed in a desiccator to cool to room temperature. The mass of the dried specimen.
2 The test piece should be tied with a thin thread, and placed in molten wax at a temperature of about 60°C for about 1s to 2s, so that the surface of the test piece is evenly coated with a layer of wax film, and its thickness is about 1mm. When there are bubbles in the wax film on the test piece, pierce it with a hot needle and spread it flat with wax liquid. After cooling, it should be called the quality of the wax-sealed test piece.
3 The wax-sealed specimen should be weighed in water.
4 Take out the test piece and weigh it again after wiping off the moisture on the surface. When the weight of the wax-sealed specimen increases after immersion in water, the test should be repeated.
5 After peeling off the sealing wax film of the wet density test piece, the water content of the rock should be measured according to the steps in Article 2.1.5 of this standard.
6 Weighing should be accurate to 0.01g.
2.3.9 The arrangement of test results shall meet the following requirements.
1 Using the volumetric method, the dry density of the rock block should be calculated according to the following formula.
In the formula.
ρd——rock block dry density (g/cm3);
ms—mass of dried test piece (g);
A - cross-sectional area of the test piece (cm2);
H - the height of the specimen (cm).
2 Using the wax sealing method, the dry density and wet density of the rock block shall be calculated according to the following formulas.
In the formula.
ρ—wet density of rock mass (g/cm3);
m - mass of wet test piece (g);
m1 - the mass of the wax-sealed specimen (g);
m2 - the weight of the wax-sealed specimen in water (g);
ρw - the density of water (g/cm3);
ρp - the density of wax (g/cm3);
w—rock water content (%).
3 When the wet density of rock block is converted into dry density of rock block, it shall be calculated according to the following formula.
4 Calculated values should be accurate to 0.01.
2.3.10 The rock density test records shall include project name, specimen number, specimen description, test method, specimen mass, specimen weighing in water, specimen size, water density, and wax density.
2.4 Water absorption test
2.4.1 Rock water absorption test shall include rock water absorption test and rock saturated water absorption test, and shall meet the following requirements.
1 The water absorption of rock shall be measured by the free immersion method.
2.Rock saturated water absorption should be measured after forced saturation by boiling method or vacuum pumping method. Rock saturated water absorption should be carried out after rock water absorption is measured.
3 While measuring the water absorption rate and saturated water absorption rate of rocks, it is advisable to use the water weighing method to measure the dry density of rock blocks and the density of rock particles.
4 This standard can be used for rocks that do not disintegrate, dissolve or shrink when exposed to water.
5 The test water should be clean water, and the density of the water should be 1g/cm3.
2.4.2 Rock specimens shall meet the following requirements.
1 Rule The test piece should meet the requirements of Article 2.3.2 of this standard.
2 Irregular specimens should be round rock blocks with a side length of 40mm to 60mm.
3 The number of test specimens in each group should be 3.
2.4.3 The description of the test piece shall comply with the provisions of Article 2.3.5 of this standard.
2.4.4 The following main instruments and equipment should be included.
1 Diamond machines, stone cutters, stone grinders and grinders, etc.
2 Ovens and dryers.
3 scales.
4 sinks.
5 Vacuum extraction equipment and boiling equipment.
6 Weighing device in water.
2.4.5 The test should be carried out according to the following steps.
1 The test piece should be placed in an oven, baked at 105°C to 110°C for 24 hours, taken out and placed in a desiccator to cool to room temperature and then weighed.
2 When the free immersion method is used, the test piece should be placed in the water tank, and water should be injected to 1/4 of the height of the test piece first, and then water should be injected to 1/2 and 3/4 of the height of the test piece every 2 hours. Fully immerse the specimen. The test piece should be taken out after freely absorbing water in water for 48 hours, and weighed after the surface moisture has been wiped off.
3 When using the boiling method to saturate the test piece, the water level in the boiling vessel should always be higher than the test piece, and the boiling time should not be less than 6 hours. The boiled test piece should be placed in the original container and cooled to room temperature, taken out and weighed after removing the surface moisture.
4 When using the vacuum pumping method to saturate the test piece, the water level in the saturation container should be higher than the test piece, and the reading of the vacuum pressure gauge should be the local atmospheric pressure value. Pump until no bubbles escape, but the pumping time should not be less than 4h. The test piece that has been vacuum pumped should be placed in the original container, let it stand for 4 hours under atmospheric pressure, take it out and remove the surface moisture, then weigh it.
5 Place the boiled or vacuum saturated test piece on the weighing device in water, and weigh it in water.
6 Weighing should be accurate to 0.01g.
2.4.6 The arrangement of test results shall meet the following requirements.
1 Rock water absorption, saturated water absorption, block dry density and particle density shall be calculated according to the following formulas.
In the formula.
ωa—rock water absorption (%);
ωsa—rock saturated water absorption (%);
mo——the mass (g) of the specimen after soaking in water for 48 hours;
ms—mass of dried test piece (g);
mp——the mass of the specimen after forced saturation (g);
mw - the weight of the forced saturation test piece in water (g);
ρw—the density of water (g/cm3).
2 Calculated values should be accurate to 0.01.
2.4.7 The rock water absorption test records shall include project name, specimen number, specimen description, test method, mass of dried specimen, mass after immersion in water, mass after forced saturation, weighing of forced saturated specimen in water, water density.
2.5 Expansion test
2.5.1 The rock expansion test shall include the rock free expansion rate test, the rock lateral restraint expansion rate test and the expansion pressure test under the condition of constant rock volume, and shall meet the following requirements.
1 The rock free expansion rate test can be used for rocks that are not easily disintegrated when exposed to water, and the free rock expansion rate test should not be used for rocks that are easily disintegrated when exposed to water.
2 For all kinds of rocks, the rock lateral restraint expansion rate test and the expansion pressure test under the condition of constant rock volume can be used.
2.5.2 Samples should be taken on site, and should be kept in a natural water state, and sampling by blasting is not allowed.
2.5.3 Rock specimens shall meet the following requirements.
1 The test piece shall be processed by dry method.
2 The diameter of the test piece for the free expansion rate test of a cylinder should be 48mm~65mm, the height of the test piece should be equal to the diameter, and the two ends should be parallel; should be parallel. The number of test specimens in each group should be 3.
3 The height of the specimen for the lateral restraint expansion rate test and the expansion pressure test under the condition of keeping the volume constant shall not be less than 20mm, or shall not be greater than 10 times the diameter of the largest mineral particle of the constituent rock, and the two ends shall be parallel. The diameter of the test piece should be 50mm ~ 65mm, and the diameter of the test piece should be 0.0mm ~ 0.1mm smaller than the diameter of the metal collar. The number of test specimens in each group for the same expansion direction shall be 3.
2.5.4 The description of the test piece should include the following contents.
1 Rock name, color, mineral composition, structure, structure, degree of weathering, properties of cement, etc.
2 The relationship between expansion deformation and loading direction and bedding, schistosity and joint fissure respectively.
3 Processing method of test piece.
2.5.5 The following main instruments and equipment should be included.
1 Diamond machine, stone cutter, stone grinder, etc.
2 Measuring platform.
3 Free expansion rate tester.
4 Lateral Constraint Expansion Rate Tester.
5 Expansion pressure tester.
6 Thermometer.
2.5.6 The free expansion rate test shall be carried out according to the following steps.
1.The test piece should be placed in the free expansion rate tester, and a water-permeable plate should be placed on the upper and lower ends of the test piece, and a metal plate should be placed on the top.
2 Dial gauges should be installed on the upper part of the test piece and the symmetrical center of the four sides to measure the axial deformation and radial deformation of the test piece respectively. A thin copper sheet should be placed where the dial indicators on the four sides are in contact with the test piece.
3 Record the readings of the dial indicator, and measure and read the deformation once every 10 minutes until the readings remain unchanged for 3 times.
4 Slowly pour distilled water into the water container until the upper permeable plate is submerged, and take a reading immediately.
5 The deformation should be measured and read once every 10 minutes within the first hour, and the deformation should be measured and read once every 1 hour thereafter until the difference between the three readings of all dial gauges is not greater than 0.001mm, but the test time after immersion in water must not be less at 48h.
6 After water is added to the test, the water level should be kept constant, and the change of water temperature should not exceed 2°C.
7 During the test and after the test, the disintegration, cracking, loss of blocks, surface muddying or softening of the test piece should be described in detail.
2.5.7 The lateral restraint expansion rate test is to be carried out according to the following steps.
1.The test piece should be put into a metal collar coated with Vaseline on the inner wall, and a thin filter paper and a water-permeable plate should be placed on the upper and lower ends of the test piece respectively.
2 A fixed metal load block should be placed on top and a vertical dial indicator should be installed. The quality of the metal load block should be able to produce a continuous pressure of 5kPa on the test piece.
3 The test and stability standards should comply with the steps in paragraphs 3 to 6 of Article 2.5.6 of this standard.
4 After the test, the muddying and softening phenomena of the test piece should be described.
2.5.8 The expansion pressure test under the condition of constant volume shall be carried out according to the following steps.
1.The test piece should be put into a metal collar coated with vatulin on the inner wall, and a thin filter paper and a metal permeable plate should be placed on the upper and lower ends of the test piece respectively.
2 According to the requirements of the expansion pressure tester, a pressurization system and a dial indicator for measuring the deformation of the test piece should be installed.
3 All parts of the instrument and the test piece should be on the same axis, and no eccentric load should appear.
4 A load of 10kPa pressure should be applied to the test piece, and the readings of the dial gauge and dynamometer should be recorded, and read once every 10 minutes until the readings remain unchanged for 3 times.
5 Slowly inject distilled water into the water container until the upper metal permeable plate is submerged, and observe the change of the dial indicator. When the deformation is greater than 0.001 mm, the applied load should be adjusted so that the expansion deformation of the test piece or the thickness of the test piece remains constant throughout the test process, and the readings of the dynamometer should be recorded.
6 At the beginning, it should be read once every 10 minutes. When the difference between the readings for 3 consecutive times is less than 0.001mm, it should be changed to reading once every 1h;. The total test time after immersion in water shall not be less than 48h.
7 After adding water for the test, keep the water level constant. The change in water temperature shall not exceed 2°C.
8 After the test, the muddying and softening phenomena of the test piece should be described.
2.5.9 The arrangement of test results shall meet the following requirements.
1 The axial free expansion rate, radial free expansion rate, lateral constraint expansion rate and expansion pressure under the condition of constant volume of rock shall be calculated respectively according to the following formulas.
In the formula.
VH——rock axial free expansion rate (%);
VD—rock radial free expansion rate (%);
VHP—rock lateral constraint expansion rate (%);
Pe—rock expansion pressure under the condition of constant volume (MPa)
△H——the axial deformation value of the specimen (mm);
H - the height of the test piece (mm);
△D——the radial average deformation value of the specimen (mm);
D——the diameter or side length of the test piece (mm);
△H1——the axial deformation value of the specimen with lateral restraint (mm);
F - axial load (N);
A - cross-sectional area of the specimen (mm2).
2 The calculated value should take 3 significant figures.
2.5.10 Rock expansion test records shall include project name, sampling location, specimen number, specimen description, specimen size, test method, temperature, test time, axial deformation, radial deformation and axial load.
2.6 Disintegration resistance test
2.6.1 The rock disintegration resistance test may be used for rocks that are easily disintegrated when exposed to water.
2.6.2 Rock specimens shall meet the following requirements.
1 The sample kept in the natural water-containing state shall be taken on site and sealed.
2 The test piece should be made into a round shape, and the mass of each piece should be 40g~60g.
3 The number of test specimens in each group should be 10.
2.6.3 The description of the test piece should include rock name, color, mineral composition, structure, structure, weathering degree, cement properties, etc.
2.6.4 The following main instruments and equipment should be included.
1 Oven and dryer.
2 scales.
3 Disintegration resistance tester (composed of a power unit, a cylindrical sieve cylinder and a water tank, wherein the cylindrical sieve cylinder is 100mm long, 140mm in diameter, and 2mm in diameter of the sieve hole).
4 thermometers.
2.6.5 The test should be carried out according to the following steps.
1 The test piece should be put into the cylindrical sieve cylinder of the disintegration resistance tester, baked at a temperature of 105°C to 110°C for 24 hours, and after taking it out, it should be put into a desiccator to cool to room temperature and weighed.
2 Put the sieve cylinder with the test piece into the water tank, pour distilled water into the water tank, and the water surface should be about 20mm below the rotating shaft. After the sieve cylinder rotates at a speed of 20r/min for 10min, the sieve cylinder containing the residual test piece should be dried at a temperature of 105°C to 110°C for 24h, cooled in a desiccator to room temperature and weighed.
3 Repeat the steps in item 2 of this article to obtain the mass of the sieve cylinder and residual test piece after the second cycle. 5 cycles can be performed as needed.
4 During the test, the water temperature should be kept within the range of 20°C±2°C.
5 After the test, the residual test piece, the color of the water and the sediment in the water should be described. As required, particle analysis, limit water content determination and clay mineral composition analysis should be carried out for the sediment in the water.
6 Weighing should be accurate to 0.01g.
2.6.6 The arrangement of test results shall meet the following requirements.
1 The disintegration resistance index of rock secondary cycle should be calculated according to the following formula.
In the formula.
Id2——rock secondary cycle disintegration resistance index (%);
ms——the drying mass of the original test piece (g);
mr—the drying mass of the residual test piece (g).
2 The calculated value should take 3 significant figures.
2.6.7 The rock disintegration resistance test records shall include project name, sampling location, test piece number, test piece description, water temperature, cycle times, and drying quality of the test piece before and after the test.
2.7 Uniaxial compressive strength test
2.7.1 All kinds of rocks that can be made into cylindrical specimens can be tested for rock uniaxial compressive strength.
2.7.2 The test piece can be prepared by drilling core or rock block. Cracks should be avoided during sample collection, transportation and preparation.
2.7.3 The size of the test piece should meet the following requirements.
1 The diameter of the cylindrical test piece should be 48mm~54mm.
2 The diameter of the test piece should be larger than the diameter of the largest particle in the rock...
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