Study on Measuring Method of Permeability Coefficient of Pervious Brick
Abstract: With the development of the economy and the process of urbanization, the surface of modern cities is gradually covered by reinforced concrete houses and impervious roads. But these impenetrable roads have brought many negative effects to the city's ecological environment. Concrete pavements lack the ability to breathe, absorb heat and penetrate rainwater compared to natural soils. A series of environmental problems have arisen: the rainwater that can penetrate the surface is significantly reduced, and the groundwater level in the city drops sharply; the impervious road surface is difficult to exchange heat and humidity with the air, resulting in a “heat island phenomenon”; short-term concentrated rainfall, A large amount of rainwater cannot penetrate into the surface in time, which is likely to cause social problems such as traffic flooding. The emergence of a new generation of green pavement permeable bricks can alleviate the above phenomenon to some extent. However, such products generally have problems such as low compressive strength, poor water permeability, and poor durability in practical applications. “Jianke” permeable bricks have changed the appearance of poor performance of permeable bricks in the past, and achieved breakthroughs in product performance, and gradually applied to municipal roads, garden landscapes and residential buildings. However, the permeability coefficient of permeable bricks affects the water permeability of permeable bricks. The determination method of water permeability coefficient is still a process of exploration. This paper makes a preliminary study on the method of measuring the permeability coefficient of permeable bricks.
Determination of water permeability coefficient of permeable bricks by measuring instrument Research status and measuring method of domestic measuring instrument
In order to cooperate with the implementation of this standard, the station will carry out subsequent improvement design based on the working principle of the permeable coefficient test device schematic provided in Article 6.6 of the standard JC/T945-2005, combined with the standard use requirements. A brick permeability coefficient tester was developed. This article describes the improvement points and use of the instrument.
1) Development of permeable coefficient tester for permeable bricks JC/T945-2005 "Water permeable bricks" provides a schematic diagram for the detection device of the permeable coefficient of permeable bricks (see Figure 1).
2) The use of water permeable brick permeability coefficient measuring instrument
1 Sample Preparation: JC/T945-2005 "Water-permeable brick" Article 6.6 Determination of water permeability coefficient The samples used were three cylinders of the same product thickness with a diameter of 75 mm on three products. The length of the permeable bricks commonly used in engineering mainly includes lOOmm, 150mm, 200mm, 250mm, 300mm, and the like. How to make samples on the cuboid or cube bricks, I started to think that it is enough to use the existing drilling machine to purchase a 75m inner diameter drill pipe. However, when the drill pipe is installed on the drilling machine, it is found that the drill is produced. The work of the specimen is far from being as simple as imagined. How to fix samples of different sizes and specifications becomes a problem, and the drilling machine itself must be fixed. I think a lot of ways, but the sample that is drilled is not a corner or a skew can not be used. After many attempts to realize a truth, there must be a device that can simultaneously lock the sample from four directions, and the samples of different sizes can be clamped, and then the drill is fixed on the device. . The sample, the device and the drilling machine are sturdy together, which is the sample preparation device. This station uses this device to easily produce a sample that conforms to the permeable instrument used in the sample preparation.
2 Vacuum device: standard requirements: the sealed and solidified sample is placed in a vacuum device and evacuated to 90 ± 10 kPa. After 30 minutes, while maintaining the vacuum, enough water is added to cover the sample and make it 10 cm higher than the sample. , stop vacuuming for 20min. The vacuum apparatus used herein utilizes existing equipment which is large in a sealed container and which is thick and expensive. If the vacuum device is only used as an accessory for permeable brick testing, the bulky sealed container can be completely reduced, and the wall thickness of the stainless steel container can be reduced, so that the cost of the device can be reduced. Only the vacuum pump used in the device can not be replaced at a low price. By testing several vacuum pumps commonly used in the market, the ultimate vacuum value does not meet the requirements stipulated by the standard. It is recommended to ensure the use of the vacuum device. The vacuum pump is still a professional manufacturer to produce a good quality product. After the sample was immersed in a vacuum apparatus for 20 minutes, it was taken out and installed on a water permeable apparatus to measure the water permeability coefficient.
3 permeable brick permeability coefficient measuring instrument operation
(1) The sample after the immersion is taken out from the vacuum device, and the end surface of the screw which is connected to the ring is connected and screwed to the water permeable cylinder of the water permeable device. Add some airless water to the permeable cylinder. Check that there is no water leakage around the sample and the connecting part. The water only seeps out from the upper and lower surfaces of the sample.
(2) Put the water-permeable cylinder with the sample connected into the water permeable instrument, put the water supply hose into the overflow water tank of the water permeable instrument, open the water supply valve, and the airless water flows into the overflow water tank through the hose. When the overflow hole flows out, the water supply hose is placed in the water-permeable cylinder, and the water supply volume is adjusted when the water level of the water-permeable cylinder rises to the overflow water of the overflow port.
(3) After the overflow of the overflow tank and the overflow port of the permeable tank are stabilized, one end of the steel ruler is placed on the horizontal drain of the overflow tank, and the side of the ruler is close to the glass tube level gauge. Read the reading level of the concave level and the ruler level of the liquid level gauge, measure the water level difference, and measure to the nearest 0.1cm. The amount of water is taken from the outlet of the overflow tank, and the amount of water (Q) flowing out in 5 minutes is recorded. Then, the permeable cylinder was taken out from the water permeable instrument, the sample was taken out, and another sample was replaced. The above steps were repeated for three times and averaged. (4) Calculate the results according to Article 6.6.4 of Standard JC/T945-2005. Explain that the permeable brick coefficient measuring instrument is used. As long as the two outlets stabilize the water, the water level in the overflow tank of the permeable meter and the water level difference in the permeable cylinder can be accurately stabilized at about 150 mm without any adjustment, because the permeable meter is permeable to water. The distance between the cylinder and the overflow sink is adjusted at the factory by the adjustment screw and can also be recalibrated by adjusting the screw. After the actual use of the water permeability meter, the operating performance fully meets the standard requirements. If the sample preparation device and the vacuum device developed in the above figure are matched, the measurement of the permeable brick coefficient is easy to complete.
Conclusion
The permeable brick permeability coefficient measuring instrument, sample preparation device and vacuum device are designed and developed for the implementation of "permeable brick" TC/T945-2005. The above figure shows that the permeable brick instrument coefficient measuring instrument is small in size, low in cost and convenient in operation. It has been used in the construction engineering testing center station of Fuzhou, and the effect is good. The product is suitable for the measurement of the permeability coefficient of the permeable bricks, and the product quality monitoring of the production enterprise and the inspection by the quality inspection department have the promotion significance.
Hangzhou Sansi Instrument Co., Ltd. Main Products:
Anchor dynamometer, geotechnical instrument, building test instrument, highway instrument, cement test instrument, asphalt instrument, analytical laboratory instrument, sputum test instrument, various analytical standard sieve, product warranty for one year, lifetime maintenance
Sales hotline: 0571-86688649
QQ: 2318806276
Determination of water permeability coefficient of permeable bricks by measuring instrument Research status and measuring method of domestic measuring instrument
In order to cooperate with the implementation of this standard, the station will carry out subsequent improvement design based on the working principle of the permeable coefficient test device schematic provided in Article 6.6 of the standard JC/T945-2005, combined with the standard use requirements. A brick permeability coefficient tester was developed. This article describes the improvement points and use of the instrument.
1) Development of permeable coefficient tester for permeable bricks JC/T945-2005 "Water permeable bricks" provides a schematic diagram for the detection device of the permeable coefficient of permeable bricks (see Figure 1).
2) The use of water permeable brick permeability coefficient measuring instrument
1 Sample Preparation: JC/T945-2005 "Water-permeable brick" Article 6.6 Determination of water permeability coefficient The samples used were three cylinders of the same product thickness with a diameter of 75 mm on three products. The length of the permeable bricks commonly used in engineering mainly includes lOOmm, 150mm, 200mm, 250mm, 300mm, and the like. How to make samples on the cuboid or cube bricks, I started to think that it is enough to use the existing drilling machine to purchase a 75m inner diameter drill pipe. However, when the drill pipe is installed on the drilling machine, it is found that the drill is produced. The work of the specimen is far from being as simple as imagined. How to fix samples of different sizes and specifications becomes a problem, and the drilling machine itself must be fixed. I think a lot of ways, but the sample that is drilled is not a corner or a skew can not be used. After many attempts to realize a truth, there must be a device that can simultaneously lock the sample from four directions, and the samples of different sizes can be clamped, and then the drill is fixed on the device. . The sample, the device and the drilling machine are sturdy together, which is the sample preparation device. This station uses this device to easily produce a sample that conforms to the permeable instrument used in the sample preparation.
2 Vacuum device: standard requirements: the sealed and solidified sample is placed in a vacuum device and evacuated to 90 ± 10 kPa. After 30 minutes, while maintaining the vacuum, enough water is added to cover the sample and make it 10 cm higher than the sample. , stop vacuuming for 20min. The vacuum apparatus used herein utilizes existing equipment which is large in a sealed container and which is thick and expensive. If the vacuum device is only used as an accessory for permeable brick testing, the bulky sealed container can be completely reduced, and the wall thickness of the stainless steel container can be reduced, so that the cost of the device can be reduced. Only the vacuum pump used in the device can not be replaced at a low price. By testing several vacuum pumps commonly used in the market, the ultimate vacuum value does not meet the requirements stipulated by the standard. It is recommended to ensure the use of the vacuum device. The vacuum pump is still a professional manufacturer to produce a good quality product. After the sample was immersed in a vacuum apparatus for 20 minutes, it was taken out and installed on a water permeable apparatus to measure the water permeability coefficient.
3 permeable brick permeability coefficient measuring instrument operation
(1) The sample after the immersion is taken out from the vacuum device, and the end surface of the screw which is connected to the ring is connected and screwed to the water permeable cylinder of the water permeable device. Add some airless water to the permeable cylinder. Check that there is no water leakage around the sample and the connecting part. The water only seeps out from the upper and lower surfaces of the sample.
(2) Put the water-permeable cylinder with the sample connected into the water permeable instrument, put the water supply hose into the overflow water tank of the water permeable instrument, open the water supply valve, and the airless water flows into the overflow water tank through the hose. When the overflow hole flows out, the water supply hose is placed in the water-permeable cylinder, and the water supply volume is adjusted when the water level of the water-permeable cylinder rises to the overflow water of the overflow port.
(3) After the overflow of the overflow tank and the overflow port of the permeable tank are stabilized, one end of the steel ruler is placed on the horizontal drain of the overflow tank, and the side of the ruler is close to the glass tube level gauge. Read the reading level of the concave level and the ruler level of the liquid level gauge, measure the water level difference, and measure to the nearest 0.1cm. The amount of water is taken from the outlet of the overflow tank, and the amount of water (Q) flowing out in 5 minutes is recorded. Then, the permeable cylinder was taken out from the water permeable instrument, the sample was taken out, and another sample was replaced. The above steps were repeated for three times and averaged. (4) Calculate the results according to Article 6.6.4 of Standard JC/T945-2005. Explain that the permeable brick coefficient measuring instrument is used. As long as the two outlets stabilize the water, the water level in the overflow tank of the permeable meter and the water level difference in the permeable cylinder can be accurately stabilized at about 150 mm without any adjustment, because the permeable meter is permeable to water. The distance between the cylinder and the overflow sink is adjusted at the factory by the adjustment screw and can also be recalibrated by adjusting the screw. After the actual use of the water permeability meter, the operating performance fully meets the standard requirements. If the sample preparation device and the vacuum device developed in the above figure are matched, the measurement of the permeable brick coefficient is easy to complete.
Conclusion
The permeable brick permeability coefficient measuring instrument, sample preparation device and vacuum device are designed and developed for the implementation of "permeable brick" TC/T945-2005. The above figure shows that the permeable brick instrument coefficient measuring instrument is small in size, low in cost and convenient in operation. It has been used in the construction engineering testing center station of Fuzhou, and the effect is good. The product is suitable for the measurement of the permeability coefficient of the permeable bricks, and the product quality monitoring of the production enterprise and the inspection by the quality inspection department have the promotion significance.
Hangzhou Sansi Instrument Co., Ltd. Main Products:
Anchor dynamometer, geotechnical instrument, building test instrument, highway instrument, cement test instrument, asphalt instrument, analytical laboratory instrument, sputum test instrument, various analytical standard sieve, product warranty for one year, lifetime maintenance
Sales hotline: 0571-86688649
QQ: 2318806276
Tel ：0571-86688649
Fax : 0571-86688346
Tel：13567560820 Manager Chen
13216192676 Manager Wang Lili
Rul：www.hzssyq.com
Mail： hzssyq@126.com
Add:No. 601, Jiangling Road, Binjiang District, Hangzhou
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