Some standard content:
Part 1 Testing methods for main building materials Standards are allocated to each item.
B6 According to the sampling quantity of 5, re-sample from 50 brick samples. According to the provisions of Table 5, 8 different random numbers are randomly determined from the range of 1 to 10. If the number is 3, 8, 10, 4, 2, 7, 5, 6, then 5 brick samples numbered 3, 13, 23, 33, 43 and 5 brick samples numbered 8, 18, 28, 38, 48 are used for strength grade inspection. 5 brick samples numbered 10, 20, 30, 40, 50 and 5 brick samples numbered 6, 16, 26, 36, 46 are used for freeze-thaw test. 5 brick samples numbered 4, 14, 24, 34, 44 are used for water absorption test. 5 brick samples numbered 2, 12, 22, 32, 42 are used for lime burst test. 5 bricks of 7, 17, 27, 37, 47 are used for frost test, and 5 bricks of 5, 15, 25, 35, 45 are used as spare brick samples. Among them, the 20 brick samples of strength grade and frost resistance performance should be tested for size deviation before testing. Additional remarks:
This standard was drafted by Northwest University of Architecture and Engineering and the Standardization Institute of the State Administration of Building Materials Industry. The main drafters of this standard are Chen Jianguang, Liu Dianwen, Zhao Qiuhui, and Chen Weiliang. 3. "Test Methods for Small Concrete Hollow Masonry Blocks" GB/T4111-19971 Scope
This standard specifies the test methods for the size, appearance, compressive strength, flexural strength, block density, hollow ratio, moisture content, water absorption, relative moisture content, drying shrinkage, softening coefficient, carbonization coefficient, frost resistance and impermeability of small concrete hollow masonry blocks.
This standard applies to small hollow masonry blocks made of various concretes for wall (hereinafter referred to as masonry blocks). 2 Dimension measurement and appearance quality inspection
2.1 Measuring tools
2.1.1 Steel ruler or steel tape measure: graduation value 1mm. 2.2 Dimension measurement
2.2.1 Length is measured in the middle of the strip surface, width is measured in the middle of the top surface, and height is measured in the middle of the top surface. Each item is measured once on the corresponding two surfaces, accurate to 1mm.
2.2.2 Wall and rib thickness are measured at the smallest part, and each two places are measured once, accurate to 1mm. 2.3 Appearance quality inspection
Figure 1 Bending measurement method
2.3.1 Bending measurement: Place the ruler against the mortar surface, mortar surface and strip surface, and measure the maximum distance between the ruler and the test piece (see Figure 1), accurate to 1mm.
2.3.2 Check for missing edges and corners: Place a ruler against the edge and measure the projection dimensions of the missing edges and corners in the length, width and height directions (see Figure 2), accurate to 1 mmo
2.3.3 Check for cracks: Use a steel ruler to measure the maximum projection dimension of the crack on the surface where it is located (such as L2 or h3 in Figure 3). If the crack extends from one surface to another, the cumulative projection dimension (such as bi+hi in Figure 3) is calculated, accurate to 1 mmo
Figure 2 Method for measuring the size of missing edges and corners
L a-The projection dimension of the missing edges and corners in the length direction; b-The projection dimension of the missing edges and corners in the width direction; h-The projection dimension of the missing edges and corners in the height direction 2.4 Measurement results
IV. Bricks and blocks
Figure 3 Crack length measurement method
L The projection dimension of the crack in the length direction;
6-The projection dimension of the crack in the width direction; h-The projection dimension of the crack in the height direction
2.4.1 The dimensional deviation of the specimen is expressed as the difference between the actual measured length, width and height and the specified dimensions. 2.4.2 The measurement results of bending, missing edges and corners and crack length are expressed as the maximum measured value. 3 Compressive strength test
3.1 Equipment
3.1.1 Material testing machine: The indication error should not be greater than 2%, and the range selection should be able to make the expected failure load of the specimen fall within 20%~~80% of the full range.
3.1.2 Steel plate: thickness not less than 10mm, plane size should be greater than 440mm×240mm. One side of the steel plate needs to be flat, and the accuracy requirement is that the flatness within the length direction is not greater than 0.1mm. 3.1.3 Glass plate: thickness not less than 6mm, plane size is the same as that of steel plate. 3.1.4 Level ruler.
3.2 Test piece
3.2.1 The number of test pieces is five blocks.
3.2.2 Treat the mortar seating surface and mortar laying surface of the test piece to make them parallel to each other. Place the steel plate on a stable base with the flat surface facing up and adjust it to level with a level ruler. First, apply a thin layer of engine oil or a layer of wet paper on the steel plate, and then apply a layer of mortar made of 1 part by weight of ordinary Portland cement above No. 325 and 2 parts of fine sand, add an appropriate amount of water, wet the mortar surface of the specimen and steadily press it into the mortar layer, so that the mortar layer is as uniform as possible, with a thickness of 3 to 5 mm. Scrape off the excess mortar along the edges of the specimen, let it stand for 24 hours, and then treat the mortar surface of the specimen according to the above method. In order to make the two surfaces parallel to each other, when treating the mortar surface, a level ruler should be placed on the mortar surface that is now facing upward and adjusted to a horizontal level. After curing for 3 days in an unventilated room with a temperature above 10°C, perform a compressive strength test. 3.2.3 To shorten the time, after the mortar layer on the mortar surface is treated, the mortar layer can be immediately laid on the upward mortar surface without standing, and a glass plate coated with oil in advance can be pressed on it. The mortar layer can be observed while pressing to eliminate all bubbles, and the level ruler can be used to adjust it to a level until the mortar layer is flat and even, with a thickness of 3 to 5 mm. 3.3 Test steps
3.3.1 Measure the length and width of each specimen according to the method in 2.2.1, and calculate the average value in each direction, accurate to 1 mm.
Part I Test Method Standard for Main Building Materials 3.3.2 Place the specimen on the pressure plate of the testing machine, so that the axis of the specimen coincides with the pressure center of the pressure plate of the testing machine, and load it at a speed of 10 to 30 kN/s until the specimen is destroyed. Record the maximum failure load P. If the pressure plate of the testing machine is not enough to cover the pressure surface of the specimen, auxiliary steel pressure plates can be added to the upper and lower pressure surfaces of the specimen. The surface finish of the auxiliary steel platen should be the same as that of the original platen of the test machine, and its thickness should be at least one-third of the distance from the edge of the original platen to the farthest corner of the auxiliary steel platen.
3.4 Calculation and evaluation of results
3.4.1 The compressive strength of each specimen is calculated according to formula (1), accurate to 0.1MPa. P
Wherein R—-compressive strength of specimen (MPa); failure load (N);
-length of the pressure surface (mm);
width of the pressure surface (mm).
3.4.2 The test results are expressed as the arithmetic mean of the compressive strength of five specimens and the minimum value of a single piece, accurate to 0.1MPa. Flexural strength test
4.1 Equipment
4.1.1 The technical requirements of the material testing machine are the same as 3.1.1. 4.1.2 Steel bars: diameter 35~40mm, length 210mm, number of three.
1/2 rib thickness
1/2 rib thickness
Figure 4 Schematic diagram of flexural strength
1—Steel rod; 2—Test specimen; 3—Flexural support
Flexural support: It is composed of two steel rods placed on the bottom plate, at least one of which can roll freely (see Figure 4). 4.2 Test specimen
4.2.1 The number of test specimens is five blocks.
4.2.2 Measure the height and width of each test specimen according to the method in 2.2.1, and calculate the average value in each direction. 4.2.3 The surface treatment of the test specimen shall be carried out in accordance with the provisions of 3.2.2 and 3.2.3. After the surface treatment, the mortar layer at the holes of the test specimen shall be removed.
4.3 Test steps
4.3.1 Place the flexural support on the pressure plate of the material testing machine, adjust the distance between the steel rod axes to make it equal to the length of the specimen minus the rib thickness at the slurry surface, and then make the center line of the flexural support coincide with the pressure center of the test machine pressure plate. 4.3.2 Place the slurry surface of the specimen on the flexural support. 4.3.3 Place a steel rod at the upper half of the length of the specimen (see Figure 4). 4.3.4 Apply load at a speed of 250N/s until the specimen is destroyed. Record the maximum failure load P. 4.4 Result calculation and evaluation
4.4.1 The flexural strength of each specimen is calculated according to formula (2) with an accuracy of 0.1MPa. 3PL
Where R is the flexural strength of the specimen (MPa); (2)
P---destructive load (N);
Axial distance between two steel bars on the flexural support (mm); Width of specimen (mm);
Height of specimen (mm).
IV. Bricks and blocks
4.4.2 The test results are expressed as the arithmetic mean of the flexural strength of five specimens and the minimum value of a single block, accurate to 0.1MPa. 5 Block density and hollow ratio test
5.1 Equipment
5.1.1 Scale: maximum weighing 50kg, sensitivity 0.05kg. 5.1.2 Pool or water tank.
5.1.3 Bucket: The size should be able to suspend and immerse a block of the main specification. 5.1.4 Hanger: See Figure 5.
5.1.5 Electric heating blast drying oven.
5.2 Number of test pieces
The number of test pieces is three blocks.
5.3 Test steps
5.3.1 Measure the length, width and height of the test piece according to the method in 2.2.1, calculate the average value in each direction, and calculate the volume V of each test piece, accurate to 0.001m2.
Figure 5 Hanger Unit: mm
1~ Angle steel (30mm×30mm); 2- Tie rod; 3- Hook (equal distance from the two tie rods)
5.3.2 Place the test piece in the electric heating blast drying oven and dry it at (105±5)℃ for at least 24h, then weigh it every 2h until the difference between the two weighings does not exceed 0.2% of the latter weighing. 5.3.3 After the test piece has cooled to a temperature no less than 20°C above room temperature in the electric blast drying oven, take it out and immediately weigh its absolute dry mass m to an accuracy of 0.05 kg.
5.3.4 Immerse the specimen in water at room temperature of 1525℃. The water surface should be more than 20mm above the specimen. After 24 hours, move them to buckets and weigh the suspended mass of the specimen (mi, accurate to 0.05kg. 5.3.5 The method for weighing the suspended mass is as follows: Place the scale on a stable support and place a bucket below the support at the point where it coincides with the center line of the scale. Place a hanger on the chassis of the scale and hang the specimen on the hanger with wire. At this time, the specimen should leave the bottom of the bucket and be completely immersed in water. Subtract the mass of the hanger and wire from the scale reading to get the suspended mass. 5.3.6 Take the specimen out of the water and place it on a wire mesh rack to drip water for 1 minute. Then wipe off the water on the inner and outer surfaces with a wrung-out wet cloth. , immediately weigh its mass in dry and wet state m2, accurate to 0.05kg. 5.4 Calculation and evaluation of results
5.4.1 The block density of each specimen is calculated according to formula (3), accurate to 10kg/m2: =mwww.bzxz.net
Where -——block density of specimen (kg/m2);absolute dry mass of specimen (kg);
V-—volume of specimen (m3).
The block density is expressed as the arithmetic mean of the block densities of three specimens. Accurate to 10kg/m3.5.4.2 The hollow ratio of each specimen is calculated according to formula (4), accurate to 1%: (3)
Where K
Part 1 Standard test methods for main building materials m2 -m1-
hollow ratio of the specimen (%);
suspended mass of the specimen (kg);
- mass of the specimen surface in dry and wet state (kg); m2-
V- — volume of the specimen (m);
d~ density of water, 1000kg/m3. The hollow ratio of the
block is expressed as the arithmetic mean of the hollow ratios of the three specimens. Accurate to 1%. 6 Water content, water absorption and relative moisture content test 6.1 Equipment
6.1.1 Electric heating forced air drying oven.
6.1.2 Scale: maximum weighing 50kg, sensitivity 0.05kg. 6.1.3 Pool or water tank.
6.2 Number of test pieces
The number of test pieces is three blocks. If the test pieces need to be transported to a place far away from the sampling location for testing, they should be packed and sealed in plastic bags immediately after sampling. | |tt||6.3 Test steps
6.3.1 Weigh the mass of the specimen mo immediately after sampling. If the specimen is transported in a sealed plastic bag, weigh the specimen together with the packaging bag before unpacking, and then subtract the mass of the packaging bag (there are water droplets precipitated from the specimen in the bag, which should be wiped dry) to obtain the mass of the specimen at the time of sampling, accurate to 0.05kg. 6.3.2 Dry the specimen to constant weight according to the methods of 5.3.2 and 5.3.3, and weigh its absolute dry mass m. 6.3.3 Immerse the specimen in water at room temperature of 15 to 25℃, and the water surface should be more than 20mm above the specimen. Take it out after 24 hours, and weigh the mass of the specimen in dry and wet state m2 according to the provisions of 5.3.6, accurate to 0.05kg. 6.4 Result calculation and evaluation
6.4.1 The moisture content of each specimen is calculated according to formula (5), accurate to 0:1%. W.-
Wherein Wi
The moisture content of the specimen (%);
-The mass of the specimen at the time of sampling (kg);
-The absolute dry mass of the specimen (kg). The moisture content of the block is expressed as the arithmetic mean of the moisture content of the three specimens. Accurate to 0.1%. 6.4.2 The water absorption of each specimen is calculated according to formula (6), accurate to 0.1%: m2-m×100
Wherein W2————The water absorption of the specimen (%); m2-
The mass of the specimen surface in dry and wet state (kg);
-The absolute dry mass of the specimen (kg).
IV. The water absorption of bricks, blocks, and
blocks is expressed as the arithmetic mean of the water absorption of the three specimens. Accurate to 0.1%. 6.4.3 The relative moisture content of the block is calculated according to formula (7), accurate to 0.1%: W1×100
W1-relative moisture content of the block (%);
W,——moisture content of the block when it leaves the factory (%); Wz-water absorption rate of the block (%).
7 Drying shrinkage test
7.1 Equipment and instruments
7.1.1 Hand-held strain gauge, gauge length 250mm. 7.1.2 Electric heating blast drying oven.
7.1.3 Pool or water tank.
Figure 66 Length measuring head
7.1.4 Length measuring head: Made of stainless steel or brass, see Figure 6.311
7.1.5 Cooling and drying box: It can be welded with iron sheets, and the size should be 650mm×600mm×220mm (length×width×height), and the lid should be tightly closed.
7.2 Test pieces
7.2.1 Each test piece consists of three blocks.
7.2.2 Use silicate cement; cement-water glass slurry or epoxy resin to glue two length measuring heads horizontally at the half-height of any side of each test piece. The spacing is 250mm. 7.3 Test steps
7.3.1 Immerse the test piece with the length measuring head firmly bonded in water at room temperature of 15-25℃, with the water surface at least 20mm above the test piece, and soak for 4d. However, the water temperature should be maintained at (20±3)℃ for 4 hours before the test. 7.3.2 Take the specimen out of the water, place it on a wire mesh rack and drip water for 1 minute, then wipe the water on the inner and outer surfaces with a wrung wet cloth, and immediately use a handheld strain gauge to measure the initial length L between the two length measuring heads, accurate to 0.001mm. The handheld strain gauge needs to be adjusted or calibrated with a standard rod before measuring the length, and each group of specimens is required to be measured within 15 minutes. 7.3.3 Place the specimen in a room and place it in an electric blast drying oven at a temperature of (50±3)℃ after 2 days. The humidity is controlled by a supersaturated solution of calcium chloride placed in a shallow dish. When the capacity of the electric blast drying oven is 1m3, the solution exposure area should be no less than 0.3m2, and the calcium chloride solid should always be exposed to the liquid surface. 7.3.4 After drying the specimen in the electric blast drying oven for 3 days, take it out and put it in a cooling drying oven at room temperature of (20±3)℃. After cooling for 3 hours, measure the length once with a handheld strain gauge. 7.3.5 Put the specimen back into the electric blast drying oven for the second cycle of drying. The drying time of the second cycle and subsequent cycles is 2 days. After drying, cool and measure the length according to the provisions of 7.3.4. To ensure uniform drying, the position of the specimen should be changed when it is placed in the electric blast drying oven after cooling and measuring the length. Repeat drying and measuring the length until the length of the specimen reaches stability. Stable length means that after the specimen is dried for three consecutive cycles under the above temperature and humidity conditions, the average length change of the three specimens does not exceed 0.005mm. The length at this time is the length after drying Lo.
7.4 Calculation and evaluation of results
7.4.1 The drying shrinkage value of each specimen shall be calculated according to formula (8), accurate to 0.01mm/m. 312
Part I
Testing method standards for major building materials
L-Lo×1000
Wherein, S is the drying shrinkage value of the specimen (mm/m); L is the initial length of the specimen (mm);
Lo is the length of the specimen after drying (mm).
7.4.2 The drying shrinkage value of the block shall be expressed as the arithmetic mean of the drying shrinkage values of the three specimens, accurate to 0.01mm/m8 Softening coefficient test
8.1 Equipment
8.1.1. The compressive strength test equipment is the same as 3.1. 8.1.2 Pool or water tank.
8.2 Test pieces
8.2.1 The number of test pieces is two groups of ten blocks. 8.2.2 The surface treatment of the test pieces shall be carried out in accordance with the provisions of 3.2.2 and 3.2.3. 8.3 Test steps
8.3.1 From the two groups of test pieces that have been surface treated and left to stand for 24 hours, randomly select a group of five test pieces and immerse them in water at room temperature of 15-25℃, with the water surface at least 20mm above the test pieces. After immersion for 4 days, take them out and drip water on a wire mesh rack for 1 minute. Then wipe the water on the inner and outer surfaces with a wrung wet cloth.
8.3.2 Perform compressive strength tests on the five saturated surface-dried test pieces and the other five air-dried comparison test pieces according to the provisions of 3.3.
8.4 Calculation and evaluation of results
8.4.1 The softening coefficient of the block is calculated according to formula (9) with an accuracy of 0.01: Rt
Softening coefficient of the block;
Where K—
R—Average compressive strength of the five saturated surface-dried test pieces (MPa); R—Average compressive strength of the five air-dried comparison test pieces (MPa). 9 Carbonation coefficient test
9.1 Equipment, instruments and reagents
9.1.1 Carbon dioxide cylinder.
9.1.2 Carbonation box: It can be made of iron plate. The size should be able to accommodate seven test pieces in two layers. The lid should be tight. 9.1.3 Carbon dioxide gas analyzer.
9.1.4 1% phenol ethanol solution: Prepared with 70% ethanol. The compressive strength test equipment is the same as 3.1.
The connection of the carbonization device is shown in Figure 7.
9.2 Test pieces
9.2.1 The number of test pieces is two groups of 12 blocks. One group of five blocks is the comparison test piece, and one group of seven blocks is the carbonization test piece, of which two blocks are used to test the carbonization condition.
IV. Bricks and blocks
Figure 7 Schematic diagram of carbonization device
Carbon dioxide cylinder; 2-ventilation rubber hose; 3-carbonization box; 4-box cover; 5-air inlet; 6-connection to gas analyzer 313
9.2.2 The surface treatment of the test piece shall be carried out in accordance with the provisions of 3.2.2 and 3.2.3. After the surface treatment, the mortar layer at the holes of the test piece shall be removed.
9.3 Test steps
9.3.1 Place seven carbonization test pieces in the carbonization box, and the distance between the test pieces shall not be less than 20mm. 9.3.2 Pass carbon dioxide gas into the carbonization box, and use the gas analyzer to control the carbon dioxide concentration in the box to (20±3)%. If the humidity in the box is too high during the carbonization process, dehumidification measures should be taken. 9.3.3 After 7 days of carbonization, split the same specimen partly every day and check the carbonization depth with 1% phenolic acid ethanol solution. When the center of the specimen does not show red, it is considered that all specimens in the box are completely carbonized. 9.3.4 Perform compressive strength test on the five completely carbonized specimens and five comparison specimens according to the provisions of 3.3. 9.4 Result calculation and evaluation
9.4.1 The carbonization coefficient of the block is calculated according to formula (10) with an accuracy of 0.01. K
Where K. Carbonization coefficient of the block;
R. — Average compressive strength of the five carbonized specimens (MPa); R—— Average compressive strength of the five comparison specimens (MPa). 10 Frost resistance test
10.1 Equipment
10.1.1 Freezer or low-temperature refrigerator: the lowest temperature can reach -20℃. 10.1.2 Pool or water tank.
10.1.3 The compressive strength test equipment is the same as 3.1. 10.2 Test pieces
The number of test pieces is two groups of ten blocks.
10.3 Test steps
10.3.1 Check the outer surfaces of the ten test pieces respectively, paint the defects, mark the numbers, and let them stand to dry. 10.3.2 Immerse a group of five freeze-thaw test pieces in a 1020℃ pool or water tank. The water surface should be 20mm higher than the test pieces. 314
Part I Test Methods for Major Building Materials Standards, the distance between test pieces shall not be less than 20mm. Another group of five test pieces is tested for comparison. 10.3.3 After immersion for 4 days, take out the test piece from the water, drip water on the bracket for 1 minute, and then wipe the water on the inner and outer surfaces with a wrung wet cloth, and immediately weigh the mass m3 of the saturated surface dry state of the test piece, accurate to 0.05kg. 10.3.4 Place five freeze-thaw specimens in a freezer or low-temperature refrigerator that has been cooled to -15°C in advance. The specimens should be placed on a grid made of wooden strips with a cross-section of 20mm×20mm, with the holes facing upward and the spacing not less than 20mm. Start timing when the temperature drops to 15°C again. Take out the specimens after freezing for 4 hours and thaw them in a pool or water tank with a water temperature of 10-20°C for 2 hours. Such a freezing and thawing process is a freeze-thaw cycle. 10.3.5 After every 5 freeze-thaw cycles, check the damage of the specimens, such as cracking, missing edges, falling corners, peeling, etc., and make a record.
After completing the specified number of freeze-thaw cycles, take the specimen out of the water and weigh the mass of the saturated surface of the specimen in a dry state after freezing and thawing according to the method in 10.3.3. 10.3.6
The mass of the saturated surface of the specimen in a dry state after freezing and thawing m40
10.3.7After the freeze-thaw specimen is left to stand for 24 hours, it shall be surface treated together with the comparative specimen according to the methods in 3.2.2 and 3.2.3. After 24 hours of surface treatment, it shall be subjected to water immersion and compressive strength tests according to the methods in 10.3.2, 10.3.3 and 3.3. 10.4 Calculation and evaluation of results
10.4.1 Report the appearance inspection results of the five freeze-thaw specimens. 10.4.2The compressive strength loss rate of the block shall be calculated according to formula (11) with an accuracy of 1%. KR=R=R×100
Loss rate of compressive strength of masonry blocks (%);
Wherein KR—
—Average compressive strength of five unfrozen and thawed specimens (MPa); RR—Average compressive strength of five frozen and thawed specimens (MPa). 10.4.3The mass loss rate of each specimen after freezing and thawing is calculated according to formula (12), accurate to 0.1%. Km=m3=m4×100
Wherein Km——mass loss rate of specimen (%); m3
—mass of specimen before freezing and thawing (kg);
—mass of specimen after freezing and thawing (kg). The mass loss rate of masonry blocks is expressed as the arithmetic mean of the mass loss rates of five frozen and thawed specimens, accurate to 0.1%. 10.4.4Frost resistance is expressed as the compressive strength loss rate, mass loss rate and appearance inspection results of the frozen and thawed specimens. 11 Impermeability test
11.1 Equipment
11.1.1 See Figure 8 for the impermeability device.
11.1.2 Pool or water tank.
11.2 Test pieces
11.2.1 The number of test pieces is three blocks.
11.2.2 Immerse the test piece in water at room temperature of 15 to 25°C. The water surface should be more than 20 mm above the test piece. After 2 hours, take the test piece out of the water and place it on a wire rack to drip water for 1 minute. Then wipe off the water on the inner and outer surfaces with a wrung wet cloth. 11.3 Test steps
Inner diameter 60
Figure 8 Schematic diagram of anti-seepage device
IV. Bricks and blocks
—Upper cover; 2—Lower support; 3—Test piece; 4—Fixing bolts; 5 Glass tube with scale; 6—Rubber sponge or foam rubber strip, 100mm thick and 20mm wide; 7—20mm periphery coated with butter or other sealing materials 315
11.3.1 Place the test piece in the anti-seepage device so that the hole is horizontal (see Figure 8). Apply butter or other sealing materials at a width of 20mm around the test piece, then lay rubber strips, tighten the fixing bolts, press the upper cover plate against the test piece, and make the periphery watertight.
11.3.2 Add water to the glass tube within 30s so that the water level is 200mm higher than the upper surface of the test piece. 11.3.3 Measure the height of the water level in the glass tube after 2 hours from the time of water addition. 11.4 Result evaluation
11.4.1Evaluate according to the maximum height of the water level drop in the glass cylinder on the three test pieces. Test report
The test report should include:
a) The inspected unit;
6) The name, number, quantity and specifications of the sample;c) The date of sample delivery (drawing);
d) Inspection items;
e) The basis standard;
f) Inspection category;
g) Test results and evaluation;
h) Report number and report date;
i) Signatures and seals of the inspection unit, the test reviewer and the technical person in charge of the unit. 316
Part I Test method standards for major building materials (II) Bricks, blocks (products) Standard name code and main technical performance of commonly used bricks and blocks (products) Excerpt 1. Brick and block (product) standard names and codes (1) "Sintered ordinary brick" (GB5101-98) (2) "Autoclaved lime sand brick" (GB11945-89) (3) "Sintered porous brick" (GB13544-92) (4) "Sintered hollow brick and hollow block" (GB13545-92) (5) "Non-sintered ordinary clay brick" (JC422-91 (96)) (6) "Fly ash brick" (JC23991 (96)) (7) "Acid-resistant brick" (GB8488-87) (8) "Autoclaved aerated concrete block" (GB1196897) (9) "Ordinary concrete small hollow block" (GB8239 -97) (10) "Medium hollow blocks" (JC71696) (11) "Fly ash blocks" (JC238-91 (96)) (12) "Autoclaved lime sand hollow bricks" (JC/T637-96) (13) "Decorative concrete blocks" (JC/T641-96) (14) "Light aggregate concrete small hollow blocks" (GB15229-94) 2. Excerpts of main technical properties of commonly used bricks and blocks (products) (1) Sintered ordinary bricks (GB5101-98) 1) Product classification and marking
Sintered ordinary bricks are divided into clay bricks (N), shale bricks (Y), coal ash bricks (M) and fly ash bricks (F) according to the main raw materials. According to the compressive strength, they are divided into five strength grades: MU30, MU25, MU20, MU15 and MU10. Bricks with qualified strength and weathering resistance are divided into three quality grades: superior (A), first-class (B), and qualified (C) according to size deviation, appearance quality, blooming and lime bursting. Superior products are suitable for clear water walls and wall decoration, and first-class and qualified products can be used for mixed water walls. Bricks with medium blooming cannot be used in wet areas. Brick product markings are written in the order of product name, specification, variety, strength grade, quality grade and standard number.
Marking example: Specification 240mm×115mm×53mm, strength grade MU15, first-class clay brick, its mark is sintered ordinary brick NMU15BGB/T5101
2) Technical requirements
① Size allowable deviation
Brick size allowable deviation shall comply with the provisions of Table 4-1. Nominal size
Sample average deviation
② Appearance quality
Sample extreme
Brick appearance quality shall comply with the provisions of Table 4-2. Item
Difference in height between two surfaces
Protruding height of impurities
Three failure dimensions of missing edges and corners
Crack length
Average deviation of samples
Range of samples
Superior products
“Not greater than
Not greater than
Not greater than
Not greater than
A: The length in the width direction of the large surface and its extension to the strip surface 6. The length direction and The length of the strip extending to the top surface or the length of the horizontal crack on the strip top surface
The complete surface shall not be less than
1. Color difference, concave and convex patterns, roughness, embossing, etc. applied for decoration shall not be considered as defects. 2. Any surface with any of the following defects shall not be called a complete surface; 2
A strip surface and a top surface
are basically the same
α) The size of the damaged surface caused by the defect on the strip surface or the top surface is greater than 10mm×10mm at the same time. 6) The width of the crack on the strip surface or the top surface is greater than 1m m, its length exceeds 30mm. IV. Bricks and blocks
Sample average deviation
Table 4-1
Sample range
(mm)Table 4-2
One side and one top side
c) Depression, sticking to the bottom, scorching The depression or protrusion on the strip side or top side exceeds 2mm, and the area size is greater than 10mm×10mm. ③ Strength grade
The strength grade of bricks shall comply with the provisions of Table 4-3. ④ Weathering resistance||tt ||Qualified products
Bricks in areas 1, 2, 3.4, and 5 of the severe weathering zone must undergo freeze-thaw tests. Bricks in other areas do not need to undergo freeze-thaw tests if their weathering resistance meets the requirements of Table 4-4. Otherwise, freeze-thaw tests must be conducted. After the freeze-thaw test, each brick sample is not allowed to have cracks, delamination, peeling, missing edges, corners, and other frost damage phenomena; the quality loss shall not exceed 2%.
③ Frosting and lime bursting
Frosting each brick sample:
Superior products: no frost.Bricks from other regions do not need to undergo freeze-thaw tests if their weathering resistance meets the requirements of Table 4-4. Otherwise, freeze-thaw tests must be conducted. After the freeze-thaw test, each brick sample is not allowed to have cracks, delamination, peeling, missing edges, corners, and other frost damage; the quality loss shall not exceed 2%.
③ Frosting and lime bursting
Frosting Each brick sample:
Superior: No frost.Bricks from other regions do not need to undergo freeze-thaw tests if their weathering resistance meets the requirements of Table 4-4. Otherwise, freeze-thaw tests must be conducted. After the freeze-thaw test, each brick sample is not allowed to have cracks, delamination, peeling, missing edges, corners, and other frost damage; the quality loss shall not exceed 2%.
③ Frosting and lime bursting
Frosting Each brick sample:
Superior: No frost.
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