JP4599519B2 - Concrete dry spraying system and concrete dry spraying method - Google Patents

Description

  The present invention relates to a concrete dry spraying system and a concrete dry spraying method in which a mixture obtained by mixing cement and aggregate is transported to a spray nozzle and water is supplied from the vicinity of the spray nozzle to spray the mixture onto a spray surface.

The dry spray method is used to cover tunnels and large cavity structures, and to prevent weathering, peeling, and peeling of slopes, slopes, and walls. In the dry spraying method, cement and aggregate are mixed with an empty mixer to make base concrete (mixture), and the base concrete is pumped from the material hose to the spray nozzle using the pumped air from the air compressor. A predetermined amount of quick setting agent and water are injected into a material hose extending in the vicinity of the spray nozzle, and base concrete containing the quick set agent and water is sprayed from the spray nozzle onto the spray surface. As an example of the dry spraying method, base concrete mixed with aggregate containing cement and rebound concrete and rapid setting agent is sent to the material hose, and a predetermined amount of water is injected into the material hose extending in the vicinity of the spray nozzle, and the spray nozzle Discloses a technique for spraying wet base concrete (see Patent Document 1). Here, the rebound concrete is concrete that rebounds from the spray surface during spraying and is not applied to the spray surface.
JP 2002-128556 A

  The dry-type spray method can be applied thinly over a wide range, and can be applied without installing a formwork on the slope or upper surface, and can also be applied to a complex-shaped spray surface. On the other hand, the amount of water supplied to the material hose must be determined on the basis of experience and sense while considering the moisture content contained in the aggregate. There is a drawback that the construction accuracy varies. The dry spraying method disclosed in the above publication uses aggregate containing rebound concrete for the base concrete sprayed on the spray surface, so that the rebound concrete can be reused. However, the moisture content of aggregates including rebound concrete cannot be determined uniformly, and the problem of having to rely on the experience and sense of the operator to determine the amount of water supplied to the material hose. It cannot be solved.

  The object of the present invention is to uniformly determine the surface water ratio of a mixture of cement and aggregate, and to regularly supply the amount of supplied water without depending on the experience and sense of the operator. It is to provide a concrete dry spraying system and a concrete dry spraying method that can be decided on.

  The first premise of the present invention for solving the above-mentioned problem is that the concrete is made by transporting a mixture of cement and aggregate to a spray nozzle, and spraying the mixture onto the spray surface while supplying water from the vicinity of the spray nozzle. It is a dry spray system.

  The first feature of the present invention in the first premise is that a concrete dry spraying system measures a first brightness of a mixture conveyed to a spray nozzle, and a plurality of preliminarily measured prototype mixtures. A surface water ratio calculation formula is determined from the correlation between the second luminance and a plurality of surface water ratios of the prototype mixture corresponding to the second luminance, and the first luminance of the mixture measured by the luminance measuring device is calculated as the surface water ratio. A control device that calculates the surface water content of the mixture by substituting into the equation, and the control device displays the calculated surface water content of the mixture.

  As an example of the present invention having the first feature, the brightness measuring device measures the first brightness of the mixture a plurality of times at a predetermined interval within a predetermined measurement time, and controls the measured first brightness. And the control device obtains a luminance average value and a standard deviation from the first group of the first luminances, and is within a reliability range determined from the luminance average value and the standard deviation from the first group. Two groups are extracted, and the surface brightness of the mixture is calculated by substituting the corrected luminance average value obtained from the second group into the surface water ratio calculation formula.

  As another example of the present invention having the first feature, in the concrete dry spraying system, the measurement time of the first luminance can be set in the range of 1 to 15 minutes, and the measurement interval of the first luminance is 2 to 2. It can be set in a range of 10 seconds, and the control device obtains the luminance average value and the standard deviation based on the first group of the first luminances measured within the measurement time.

  As another example of the present invention having the first feature, in the concrete dry spraying system, the reliability when extracting the second group having the first luminance can be set in the range of 68.26 to 99.73%. It is.

  As another example of the present invention having the first feature, the concrete dry spraying system includes an automatic water supply device that automatically supplies the amount of water supplied from the control device to the vicinity of the spray nozzle. The control device calculates the supply water amount by subtracting the water content from the preset water amount while calculating the water content of the aggregate from the surface water rate calculated based on the formula for calculating the surface water rate. The amount of water is output to the automatic water supply device.

  As another example of the present invention having the first feature, the luminance measuring device partially covers a mixture moving continuously in one direction to create a dark place, and a mixture moving in the dark place. And a luminance meter for measuring the first luminance of the mixture illuminated by the light emitted from the light source.

  The second premise of the present invention for solving the above problems is that of a concrete in which a mixture in which cement and aggregate are mixed is conveyed to a spray nozzle, and water is supplied from the vicinity of the spray nozzle while spraying the mixture onto the spray surface. This is a dry spray method.

  The second feature of the present invention according to the second premise is that the concrete dry spraying method includes a brightness measurement step of measuring the first brightness of the mixture conveyed to the spray nozzle, and a plurality of preliminarily measured prototype mixtures. A surface water ratio calculation formula is determined from the correlation between the second brightness and a plurality of surface water ratios of the prototype mixture corresponding to the second brightness, and the first brightness of the mixture measured in the brightness measurement step is determined as the surface water ratio. There is a surface water ratio calculating step of calculating the surface water ratio of the mixture by substituting into the calculation formula, and a surface water ratio display step of displaying the calculated surface water ratio of the mixture.

  As an example of the present invention having the second feature, in the luminance measurement step, the first luminance of the mixture is measured a plurality of times at a predetermined interval within a predetermined measurement time, and the measured first luminance is supplied to the control device. In the process of calculating the surface water ratio, the average brightness value and the standard deviation are obtained from the first group of the first brightness, and within the reliability range determined from the average brightness value and the standard deviation from the first group. The existing second group is extracted, and the corrected luminance average value obtained from the second group is substituted into the surface water ratio calculation formula to calculate the surface water ratio of the mixture.

  As another example of the present invention having the second feature, the concrete dry spraying method includes an automatic water supply step of automatically supplying water to the vicinity of the spray nozzle, While calculating the water content contained in the aggregate from the surface water rate calculated based on the water content calculation formula, the water content is calculated from the preset water content, and the water supply is calculated. The supply amount of water calculated in the water ratio calculation step is supplied.

  As another example of the present invention having the second feature, in the luminance measurement step, a dark area is created by partially covering the mixture moving continuously in one direction, and the mixture moving in the dark area is irradiated with light. However, the first brightness of the mixture illuminated by the irradiated light is measured.

  According to the concrete dry-spraying system of the present invention, the surface water ratio of the mixture is calculated by substituting the measured first luminance of the mixture into the surface water ratio calculation formula. Further, since the calculated surface water ratio is displayed, the amount of water supplied by the operator can be regularly determined based on the displayed surface water ratio. This dry spray system does not require workers on site to determine the amount of water supplied based on experience and sense, and can improve the workability and quality of dry spray regardless of the level of the worker's ability. In addition, the construction accuracy can be made uniform.

  A luminance average value and a standard deviation are obtained from the first group of the first luminance, a second group existing within a reliability range determined from the luminance average value and the standard deviation is extracted from the first group, and the second group is extracted. The concrete dry spraying system that calculates the surface water ratio of the mixture by substituting the corrected average brightness value obtained from the above into the surface water ratio calculation formula adopts the reliability in the probability distribution and is within the range of reliability. Since the corrected average brightness value obtained from the group is substituted into the surface water ratio calculation formula, a stable surface water ratio with little fluctuation can be obtained. This dry spray system can uniformly determine the stable surface water ratio of the mixture without depending on the experience and sense of the operator, regardless of the ability of the operator, Quality can be improved and construction accuracy can be made uniform.

  The measurement time of the first luminance can be set in the range of 1 to 15 minutes, and the measurement interval of the first luminance can be set in the range of 2 to 10 seconds, and the first luminance measured within the measurement time can be set. The concrete dry-type spraying system that calculates the average brightness value and the standard deviation based on the first group has the above-mentioned ranges of the first brightness measurement time and the measurement interval according to the spraying time of the mixture and the spraying amount per unit time of the mixture. And can set the optimal measurement time and measurement interval for each mixture, so that a stable surface water ratio with little fluctuation can be obtained, and the workability and quality of dry spraying are ensured. Can be improved.

  The concrete dry spray system that can set the reliability when extracting the second group of the first luminance in the range of 68.26 to 99.73% is suitable for the mixing ratio of the components of the mixture and the moisture content of the aggregate. At the same time, the reliability can be determined, and the surface water ratio of the mixture can be determined based on high reliability. Therefore, a stable surface water ratio with little fluctuation can be determined, and the workability and quality of dry spraying can be determined. Can be reliably improved.

  While calculating the water content of the aggregate from the surface water ratio calculated based on the formula for calculating the surface water ratio, subtract the water content from the preset water volume to calculate the supply water volume and spray the calculated supply water volume. The concrete dry spraying system that automatically supplies the vicinity of the nozzle automatically supplies the amount of water supplied, so there is no need to estimate the amount of water supplied by the operator from the surface water ratio of the mixture. The operator does not need to manually adjust the amount of water supplied. This dry spraying system can uniformly calculate the amount of water supplied considering the moisture content of the aggregate with high accuracy, and automatically calculates the supplied amount of water without the operator's work. Since it can supply, the workability and quality of dry-type spraying can be improved reliably.

  A concrete in which a luminance measuring device is formed of a covering member that creates a dark place, a light source that irradiates light to the mixture that moves in the dark place, and a luminance meter that measures the first luminance of the mixture illuminated by the light emitted from the light source The dry spray system of this system places the mixture in a dark place when measuring the brightness to prevent the mixture from being exposed to excessive light, and further irradiates the mixture located in the dark place from a predetermined light source. Thus, since the mixture is irradiated with only a certain amount of light, the first luminance of the mixture can always be measured under a certain condition. This dry spraying system can accurately measure the first luminance of the mixture under a certain condition, and can uniformly determine the surface water content of the mixture based on the first luminance. The workability and quality can be improved reliably, and the work accuracy can be made uniform.

  According to the concrete dry spraying method according to the present invention, the surface water ratio of the mixture is calculated by substituting the measured first luminance of the mixture into the surface water ratio calculation formula. Further, since the calculated surface water ratio is displayed, the amount of water supplied by the operator can be regularly determined based on the displayed surface water ratio. This dry spraying method does not require workers on site to rely on experience and sense to determine the amount of water supplied, and can improve the workability and quality of dry spraying regardless of the level of the worker's ability. In addition, the construction accuracy can be made uniform.

  A luminance average value and a standard deviation are obtained from the first group of the first luminance, a second group existing within a reliability range determined from the luminance average value and the standard deviation is extracted from the first group, and the second group is extracted. The concrete dry spraying method, which calculates the surface water ratio of the mixture by substituting the corrected average brightness value obtained from the above into the formula for calculating the surface water ratio, employs the reliability in the probability distribution and is within the reliability range. Since the corrected average brightness value obtained from the group is substituted into the surface water ratio calculation formula, a stable surface water ratio with little fluctuation can be obtained. This dry spraying method can uniformly determine the stable surface water ratio of the mixture without depending on the experience and sense of the operator, regardless of the ability of the operator, Quality can be improved and construction accuracy can be made uniform.

  While calculating the water content of the aggregate from the surface water ratio calculated based on the formula for calculating the surface water ratio, subtract the water content from the preset water volume to calculate the supply water volume and spray the calculated supply water volume. In the concrete dry spraying method, which is automatically supplied to the vicinity of the nozzle, the amount of water supplied is automatically supplied, so there is no need to estimate the amount of water supplied by the operator from the surface water ratio of the mixture. The operator does not need to manually adjust the amount of water supplied. This dry spraying method can uniformly calculate the amount of water supply considering the moisture content of the aggregate with high accuracy, and automatically calculates the water supply amount calculated without any operator work. Since it can supply, the workability and quality of dry-type spraying can be improved reliably.

  In the luminance measurement process, the first brightness of the mixture illuminated by the irradiated light is created by partially covering the mixture moving continuously in one direction to create a dark place and irradiating the mixture moving in the dark place with light. The dry spray method for measuring concrete is to place the mixture in a dark place in the luminance measurement process, thereby preventing the mixture from being exposed to extra light, and further irradiating the mixture located in the dark place with light. Thus, since the mixture is irradiated with only a certain amount of light, the first luminance of the mixture can always be measured under a certain condition. This dry spraying method can accurately measure the first luminance of the mixture under a certain condition, and can uniformly determine the surface water content of the mixture based on the first luminance. The workability and quality can be improved reliably, and the work accuracy can be made uniform.

  The details of the concrete dry spraying system and concrete dry spraying method according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a configuration diagram of a dry spray system shown as an example, and FIG. 2 is a perspective view of a luminance measuring device 11 shown as an example. FIG. 3 is a diagram showing an example of the correlation between the brightness of the prototype base concrete and the surface water percentage. In FIG. 1, the illustration of the unit 23 forming the luminance measuring device 11 is omitted. In FIG. 2, the vertical direction is indicated by an arrow A, the horizontal direction is indicated by an arrow B, and the front-rear direction is indicated by an arrow C. The dry spray system includes a luminance measuring device 11 that measures the luminance of the base concrete 10 (dry mix mixture), a control device 12, a concrete conveying device 14 that supplies the base concrete 10 to the material hose 13, and a material hose 13. An air compressor 16 for supplying concrete pumped air from the end 15, a quick setting agent supply device 17 (within a two-dot chain line) for supplying a quick setting agent toward the material hose 13, and water for the material hose 13 It is formed of an automatic water supply device 18 (inside the alternate long and short dash line) that automatically supplies and a spray nozzle 20 attached to the tip 19 of the material hose 13. Predetermined electric power is supplied to the luminance measuring device 11, the control device 12, the concrete conveying device 14, the air compressor 16, the quick setting agent supplying device 17, and the automatic water supplying device 18 through wiring (not shown). .

  The base concrete 10 is made by kneading cement and aggregate with an empty kneading mixer (not shown). The base concrete 10 moves from the empty kneading mixer to the belt conveyor 21, moves in one direction on the belt conveyor 21 as shown by arrows L <b> 1 in FIGS. There is no particular limitation on the type of cement to be used, and any of premix cement, Portland cement, blast furnace cement, fly ash cement, silica cement, etc., or a mixture of these in a predetermined ratio may be used. it can. These cements are in a dry state. As the aggregate, coarse aggregate and fine aggregate are used. The coarse aggregate includes gravel, crushed stone, crushed sand, blast furnace slag aggregate, ferronickel slag aggregate, copper slag aggregate, artificial lightweight aggregate, or an aggregate obtained by mixing them at a predetermined ratio Can be used. For fine aggregate, use one of sand, blast furnace slag aggregate, ferronickel slag aggregate, copper slag aggregate, artificial lightweight aggregate, or an aggregate obtained by mixing them at a predetermined ratio. Can do. Coarse aggregates and fine aggregates contain a predetermined amount of moisture.

  The luminance measuring device 11 is installed approximately in the middle of the belt conveyor 21. As shown in FIG. 2, the luminance measuring device 11 includes a unit 23 (covering member) that partially covers the base concrete 10 moving on the belt conveyor 21 to create a dark place 22, and base concrete that moves in the dark place 22. The LED 24 (light source) that irradiates the light 10 and the luminance meter 25 that measures the luminance of the base concrete 10 illuminated by the light emitted from the LED 24 are formed. The LED 24 and the luminance meter 25 are connected to the control device 12 via an interface 26 (wired or wireless). The unit 23 is a rectangular parallelepiped that is long above the belt conveyor 21 in the front-rear direction. The unit 23 is formed of a top wall 27 and four side walls 28 extending downward from the top wall 27. Four legs 30 extending downward are attached to the corners 29 where the side walls 28 intersect. On the side wall 28, an openable / closable window 31 for looking into the dark place 22 is formed. Each wall 27, 28 and leg 30 are made of metal or plastic. Each of the walls 27 and 28 blocks light incident from the outside.

  The LED 24 is fixed to the top wall 27 of the unit 23 via fixing means (not shown). The light irradiation part 31 of the LED 24 is directed downward from an opening 32 formed substantially at the center of the top wall 27 and faces the belt conveyor 21. Light from the light irradiation unit 31 is irradiated from above the base concrete 10 moving in the dark place 22, and is evenly applied to substantially the entire area of the base concrete 10 located in the dark place 22. In addition to the LED 24, other light sources such as an incandescent bulb and a fluorescent lamp can be used. The luminance meter 25 is fixed to the top wall 27 of the unit 23 through fixing means (not shown). The luminance light receiving portion 33 of the luminance meter 25 faces downward from the opening 32 of the top wall 27 and faces the belt conveyor 21. The height and the mounting position of the luminance meter 25 are determined so that the luminance of the entire area of the base concrete 10 located in the dark place 22 can be measured.

  The luminance measuring device 11 measures the luminance of the base concrete 10 located in the dark place 22 a plurality of times in a time series at predetermined intervals within a predetermined measurement time (luminance measuring step), and the measured luminance is transmitted to the control device 12. Output sequentially. The luminance measurement time and measurement interval in the luminance measurement device 11 are set by the control device 12. The luminance measurement time can be set in the range of 1 to 15 minutes, and the luminance measurement interval can be set in the range of 2 to 10 seconds. In this system, the brightness measurement time and the measurement interval can be adjusted in the above range according to the spraying time of the base concrete 10 and the amount of spraying of the base concrete 10 per unit time. Time and measurement interval can be set.

  The control device 12 is a computer having a central processing unit (CPU or MPU) and a large capacity hard disk (memory), and is equipped with a keyboard 34 and a display 35. The hard disk of the control device 12 stores application programs for causing the control device 12 to execute various means. The central processing unit of the control device 12 activates an application program from the memory based on control by the operating system, and executes the following means according to the activated application program.

  The central processing unit of the control device 12 includes a plurality of brightnesses (second brightness) of the prototype base concrete (prototype dry mix mixture) (not shown) measured in advance and a plurality of surface waters of the prototype base concrete corresponding to these brightnesses. Correlation specifying means for specifying the correlation with the rate is executed, and correlation storing means for storing the specified correlation in the hard disk is executed. The central processing unit executes calculation formula determining means for determining the surface water ratio calculation formula of the prototype base concrete from the stored correlation, and executes calculation formula storage means for storing the determined surface water ratio calculation formula in the hard disk. The central processing unit substitutes the corrected luminance average value of the base concrete 10 output from the luminance measuring device 11 into the surface water ratio calculating formula, and calculates the surface water ratio calculating means (surface water) for calculating the surface water ratio of the base concrete 10. The surface water ratio display means (surface water ratio display process) for displaying the calculated surface water ratio of the base concrete 10 on the display 35 is executed. The central processing unit executes a moisture content calculating means for calculating the moisture content of the aggregate contained in the base concrete 10 from the surface moisture rate of the base concrete 10 calculated based on the formula for calculating the surface moisture rate, and is set in advance. Supply water amount calculation means for subtracting the water content from the set water amount and calculating the supply water amount to be supplied is executed. Further, a supply water amount output means for outputting the calculated supply water amount to the automatic water supply device 18 is executed, and a supply water amount display means for displaying the water supply water amount on the display 35 is executed.

  An example of specifying the correlation between the luminance of the prototype base concrete and the surface water ratio and an example of determining the surface water ratio calculation formula from the specified correlation are as follows. For example, ordinary Portland cement in a dry state is prepared, and gravel (coarse aggregate) or sand (fine aggregate) having an average particle diameter in a predetermined range and having a predetermined moisture content is facilitated. Prototype base concrete is made by mixing ordinary Portland cement, gravel and sand with a mixer. A predetermined amount of moisture is contained in the prototype base concrete because the moisture of the aggregate is dispersed. Repeat this procedure to make multiple prototype base concretes with different surface water ratios. After preparing these prototype base concretes, the brightness (second brightness) of each prototype base concrete is measured, the surface water ratio of each prototype base concrete is measured, and the measured brightness and surface moisture ratio are measured via the keyboard 34. To the control device 12. The central processing unit of the control device 12 inputs the luminance (%) and the surface water ratio (indicated by the luminance-surface water ratio correlation table (see FIG. 3) where the vertical axis represents the luminance and the horizontal axis represents the surface water ratio. %) (Black point in FIG. 3) is displayed, and the correlation between the luminance and the surface water ratio is specified (correlation specifying means). Next, a line segment having a predetermined inclination is connected by connecting these intersections, and a function (y = −ax + b) of the line segment is used as a surface water ratio calculation formula (calculation formula determination means). The central processing unit stores the specified luminance-surface water rate correlation table in the hard disk (correlation storage unit), and stores the determined surface water rate calculation formula in the hard disk (calculation formula storage unit). As is apparent from FIG. 3, the surface water ratio increases as the luminance decreases.

  The central processing unit of the control device 12 corrects the luminance (first luminance) of the base concrete 10 output from the luminance measuring device 11 based on a predetermined reliability in the probability distribution, and calculates a corrected luminance average value of the corrected luminance. Substitute in the formula for calculating the surface water ratio. Specifically, it is as follows. The central processing unit integrates a plurality of luminances (first group) output from the luminance measuring device 11 to calculate a luminance first integrated value, and divides the luminance first integrated value by the number of measurements to obtain the luminance average value. Calculate the standard deviation. Next, among a plurality of luminances (first group) output from the luminance measuring device 11, a plurality of luminances (seconds) existing within a reliability range (confidence interval) determined from the luminance average value and the standard deviation. (Group) is extracted, a plurality of luminance values existing within the reliability range are integrated to calculate a luminance second integrated value, and the luminance second integrated value is measured the number of times (excluding the number of luminance measurements outside the reliability range). ) To calculate a corrected luminance average value. The central processing unit sequentially calculates the corrected luminance average value for each set measurement time, and sequentially calculates the surface water rate of the moving base concrete 10 by substituting the corrected luminance average value into the surface water rate calculating formula. (Surface water ratio calculating means), the water content of the aggregate contained in the base concrete 10 is sequentially calculated (water content calculating means), and the supplied water amount of the supplied water is sequentially calculated (supplied water amount calculating means). The central processing unit sequentially outputs the supply water amount to the automatic water supply device 18 (supply water amount output unit), and sequentially displays the surface water rate and the supply water amount on the display 35 (surface water rate display unit, supply water amount display unit). .

  In the system, the reliability when the control device 12 calculates the corrected brightness average value is μ (average value) ± 1σ (one standard deviation), μ (average value) ± 2σ (twice standard deviation), μ (Average value) ± 3σ (three times the standard deviation) can be set. In μ ± 1σ, the reliability is 68.26%, and in μ ± 2σ, the reliability is 95.44%. In μ ± 3σ, the reliability is 99.73%. The system can determine the reliability in accordance with the mixing ratio of the constituent materials of the base concrete 10 and the moisture content of the aggregate contained in the base concrete 10, and the surface water ratio of the base concrete 10 is determined based on the high reliability. Can be sought.

  The concrete conveying device 14 is formed of a hopper 36 that receives the base concrete 10 carried by the belt conveyor 21 and a concrete pump (not shown) that pumps the base concrete 10 toward the concrete hose 37. The concrete hose 37 is connected to the material hose 13 via the Y-shaped pipe 38. The air compressor 16 sends the concrete compressed air to the material hose 13 via the air hose 39. The air hose 39 is connected to the material hose 13 through the Y-shaped tube 38. A flow control valve 40 and a flow meter 41 are attached to the air hose 39. The amount of concrete compressed air flowing through the air hose 39 is adjusted by a valve 40.

  The quick setting agent supply device 17 is formed of an air compressor 42 that forcibly conveys a powder quick setting agent by compressed air, and a quick setting agent supply unit 43 that supplies a set amount of the quick setting agent. The compressor 42 is connected to the supply unit 43 via a quick setting agent supply hose 44. The supply hose 44 is connected to the intermediate portion 46 of the material hose 13 via the Y-shaped tube 45. A slurrying nozzle 47 is attached to the supply hose 44. The quick setting agent accommodated in the supply unit 43 is supplied toward the material hose 13 by the quick setting agent compressed air supplied from the air compressor 42. The supply unit 43 adjusts the amount of the rapid setting agent to be supplied by controlling the flow rate and pressure of the compressed air supplied from the air compressor 42.

  The automatic water supply device 18 includes a tank 48 that contains water, a pump 49 that forcibly supplies water in the tank 48 toward the slurry nozzle 47, a flow meter 50 that measures the flow rate of water, and a pump 49. And a control panel 51 that adjusts the flow rate of water by controlling the output of. The control panel 51 is connected to the control device 12 via the interface 52. The tank 48 and the pump 49 are connected to each other via a water hose 53. The water hose 53 is connected to the slurrying nozzle 47. The flow meter 50 is attached to a water hose 53 that extends downstream from the pump 49. The automatic water supply device 13 automatically supplies water in the amount of supply water (discharge amount from the nozzle 20 per unit time (liter / minute)) output from the control device 12 (automatic water supply step). Note that the amount of water supplied per unit time can be freely changed by the operator manually operating a water amount adjusting unit (not shown) of the control panel 51.

  In this concrete dry spray system, the base concrete 10 is conveyed from the material hose 13 to the spray nozzle 20 using compressed air, and a slurry quick-setting agent is injected into the material hose 13 extending in the vicinity of the spray nozzle 20, The base concrete 10 containing the quick setting agent is sprayed from the nozzle 20 onto the spray surface. In this system, water is continuously mixed into the powder quick-setting agent using the slurrying nozzle 47, the powder quick-setting agent is made into a slurry, and the slurry quick-setting agent is mixed into the base concrete 10. . By using the slurry quick setting agent, the mixing property with the base concrete 10 is improved, and the generation of dust during spraying can be prevented. As the powder setting agent, calcium aluminate, calcium sulfoaluminate, calcium sodium aluminate, or alumina can be used. Water can be water, tap water, river water, lake water, or the like.

  FIG. 4 is a diagram illustrating an example of the luminance measurement time and the measurement interval, and FIG. 5 is a flowchart illustrating an example of the calculation of the surface water ratio and the supply water amount performed by the control device 12. In FIG. 4, the passage of time is indicated by an arrow L2. In FIG. 4, the surface water ratio and the supply water amount calculated by the control device 12 are displayed on the display 35. As a step before starting the system, the same material as that of the prototype base concrete used for specifying the correlation stored in the hard disk of the control device 12 is prepared. For example, if the prototype base concrete used to identify the correlation is made of ordinary Portland cement and gravel (coarse aggregate) and sand (fine aggregate) with an average particle size in the specified range, they are the same Prepare normal Portland cement, gravel and sand. In addition, if the prototype base concrete is made of fly ash cement, crushed stone (coarse aggregate) with an average particle size within a predetermined range, and blast furnace slag aggregate (fine aggregate), the same fly ash cement and Prepare crushed stone and blast furnace slag aggregate.

  Next, the system is started and various conditions are input to the control device 12. The conditions include luminance measurement time and measurement interval, reliability, supply amount of powder quick setting agent, output of air compressors 16 and 42, output of pump 49, and the like. 4 and 5, one unit of measurement of luminance measurement time is 3 minutes, and the measurement interval is 5 seconds. Therefore, the brightness measuring device 11 measures the brightness of the base concrete 10 every 5 seconds. However, the measurement time and the measurement interval are not limited thereto, and as described above, the measurement time can be set in the range of 1 to 15 minutes, and the measurement interval can be set in the range of 2 to 10 seconds. . The reliability is assumed to be set to μ (average value) ± 1σ (one time of standard deviation). However, the reliability is not limited thereto, and as described above, the reliability can be any of μ (average value) ± 2σ (twice the standard deviation) and μ (average value) ± 3σ (three times the standard deviation). It can also be set.

  When the system is activated, the LED 24 of the luminance measuring device 11 is turned on to illuminate the dark place 22, and the luminance meter 25 can measure the luminance of the base concrete 10 moving in the dark place 22. The operator puts the same cement and aggregate as the prototype base concrete into an empty kneading mixer. For example, ordinary Portland cement, gravel and sand are put into a mixer. Alternatively, fly ash cement, crushed stone, and blast furnace slag aggregate are put into a mixer. In the mixer, these materials are kneaded to form the base concrete 10. Water contained in the aggregate is dispersed in the base concrete 10. Therefore, the base concrete 10 contains a predetermined amount of moisture. The base concrete 10 moves from the mixer onto the belt conveyor 21. The luminance measuring device 11 measures the luminance of the base concrete 10 moving in the dark place 22 every 5 seconds (S-1). The luminance measuring device 11 sequentially outputs the measured luminance to the control device 12.

  The control device 12 counts 3 minutes as one measurement unit, and counts 6 minutes as a reliability determination unit. The central processing unit of the control device 12 divides the luminance measured by the luminance measuring device 11 into 6 minutes, and integrates 72 pieces of luminance data (first group) of 72 measurement times for 6 minutes to obtain the luminance first integration. The value is calculated, the luminance first integrated value is divided by 72, the luminance average value is calculated, and the standard deviation is calculated. Next, the central processing unit identifies non-accepted data out of the range of reliability (μ ± 1σ) determined from the luminance average value and standard deviation (outside the confidence interval) out of 72 luminance data (first group). (S-2). Here, the non-accepted data is data that is further on the minus side from the point moved by α to the minus side from the luminance average value (less than −α), and is further on the plus side from the point that is moved from the luminance average value to the plus side by α. Data (exceeding + α).

  The central processing unit of the control device 12 excludes non-employed data from 36 pieces of luminance data for the latter half of the 72 pieces of luminance data (first group) (S-3). The remaining luminance data (second group) existing within the reliability range is extracted. The central processing unit calculates the luminance second integrated value by integrating the remaining luminance data, and calculates the corrected luminance average value by dividing the luminance second integrated value by 36 minus the number of measurements of non-accepted data. (S-4). The central processing unit substitutes the corrected luminance average value into the surface water ratio calculation formula, calculates the surface water ratio of the base concrete 10 (S-5), and displays the calculated surface water ratio on the display 35 (S-6). ). Specifically, when the surface water ratio calculation formula is (y) = − 1.5004 (x) +14.599 and the corrected luminance average value (x) is 6.39 (%), the surface water ratio ( y) =-1.5004 × 6.39 + 14.599 = 5.0 (%), and the surface water content of 5.0 (%) is displayed on the display 35.

  Next, the central processing unit of the control device 12 calculates the water content of the aggregate contained in the base concrete 10 from the surface water rate calculated based on the surface water rate calculation formula, and includes the water content from the preset set water amount. The amount of supplied water is calculated by subtracting the amount of water (S-7), the calculated amount of supplied water is displayed on the display 35, and the amount of supplied water is output to the automatic water supply device 18 (S-8). Specifically, the amount of water supplied per minute is (a), the set amount of water per minute is (b), the water content is (c), the weight of the aggregate contained in the base concrete 10 is (d), the surface Assuming that the water content is (y), supply water amount (a) = set water content (b) −water content (b), water content (b) = weight of aggregate (d) × surface water content (y) . When the set amount of water per minute (b) is 20 (liters / minute), the aggregate weight (d) is 100 (kg / minute), and the surface water ratio is (y) 5.0 (%) The amount of water (b) = 100 × 0.05 = 5 (liter / minute), the amount of supplied water (a) = 20−5 = 15 (liter / minute), and the amount of supplied water 15 (liter / minute) is displayed on the display 35. At the same time, it is output to the automatic water supply device 18.

  The operator selects continuous operation or stop of the system (S-9). When the operator selects to stop the system, the operation of the system is stopped. When the operator selects the continuous operation of the system, the central processing unit of the control device 12 returns to Step 2 (S-2) and repeats the processes after Step 2. As shown in FIG. 4, the central processing unit sequentially calculates the surface water ratio and the amount of supplied water by moving average. Specifically, out of the 72 measurement times, 36 of the first half are excluded, and 36 times measured for 3 minutes are added to 36 times of the second half to obtain 72 measurement times. While adopting, the corrected luminance average value is calculated from the added luminance data of 36 times, the surface water ratio of the base concrete 10 is calculated from the corrected luminance average value, the moisture content of the aggregate is calculated, and the supplied water Calculate the amount of water supply. The central processing unit displays the surface water ratio and the supply water amount sequentially calculated by the moving average on the display 35 and outputs the sequentially calculated supply water amount to the automatic water supply device 18. In the automatic water supply device 18, the control panel 51 adjusts the output of the pump 49 according to the supply water amount (liters / minute) output from the control device 12, and automatically supplies the supply water amount (liters). / Min) of water is supplied to the slurrying nozzle 47.

  This dry spray system and dry spray method calculates the surface water ratio of the base concrete 10 by substituting the measured corrected average brightness value of the base concrete 10 into the surface water ratio calculation formula, and further uses the surface water ratio. Therefore, the surface water rate of the base concrete 10 and the water supply amount can be determined uniformly. In the dry spray system and the dry spray method, the calculated supply water amount is output to the automatic water supply device 18, and the water of the supply water amount is automatically supplied from the device 18, so that the operator can rely on experience and sense to It is not necessary to determine the amount of water supplied, and it is not necessary to manually adjust the amount of water supplied by the operator based on the surface water ratio of the base concrete 10. The dry spray system and the dry spray method can uniformly calculate the amount of water supplied in consideration of the moisture content of the aggregate contained in the base concrete 10 with high accuracy. Therefore, regardless of the level of the operator's ability, the workability and quality of dry spraying can be reliably improved, and the work accuracy can be made uniform. Can be planned.

  In the dry spray system and the dry spray method, a brightness average value and a standard deviation are obtained from a measured brightness (first brightness) group (first group), and a group (within the reliability range) from the first group ( Since the surface water ratio of the base concrete 10 is calculated by extracting the second group) and substituting the corrected luminance average value obtained from the group into the surface water ratio calculation formula, obtaining a stable surface water ratio with little fluctuation Can do. In the dry spray system and the dry spray method, the brightness measuring device 11 irradiates light to the unit 23 that creates the dark place 22 and the base concrete 10 that moves in the dark place 22, and the base concrete illuminated by the light emitted from the LED 24. Since the base concrete 10 is positioned in the dark place 22 when measuring the brightness, it is possible to prevent the base concrete 10 from being irradiated with extra light. it can. In the dry spraying system and the dry spraying method, the base concrete 10 located in the dark place 22 is irradiated with light from the LED 24, so that the base concrete 10 is irradiated with only a certain amount of light. Therefore, the brightness of the base concrete 10 is always measured. This can be performed under certain conditions, and the brightness of the base concrete 10 can be accurately measured under certain conditions.

  In the dry spray system and the dry spray method, the supply water amount is output to the automatic water supply device 18, and the control panel 51 adjusts the output of the pump 49 to automatically supply the supply water amount. For example, the operator may manually adjust the 49 output or a valve mechanism (not shown) to supply a supply amount of water. In this case, the supply water amount calculated by the control device 12 is not output to the supply device 18, the supply water amount is displayed on the display 35, and the water supplied from the supply device 18 while the operator visually observes the displayed supply water amount. Adjust the amount. Further, in the dry spray system and the dry spray method, the surface brightness of the base concrete 10 is calculated by substituting the corrected luminance average value into the formula for calculating the surface water ratio, but the base concrete 10 measured by the measuring device 11 is calculated. The average value of the luminance (first luminance) may be substituted into the surface water ratio calculation formula to calculate the surface water ratio of the base concrete 10, and the luminance of the base concrete 10 measured by the measuring device 11 (first luminance). May be directly substituted into the surface water ratio calculation formula to calculate the surface water ratio of the base concrete 10.

The block diagram of the dry-type spray system shown as an example. The perspective view of the brightness | luminance measuring apparatus shown as an example. The figure which shows an example of the correlation of the brightness | luminance and surface water rate of trial manufacture base concrete. The figure which shows an example of the measurement time and measurement interval of a brightness | luminance. The flowchart which shows an example of calculation of the surface water rate and supply water amount performed by a control apparatus.

Explanation of symbols

10 Base concrete (mixture)
DESCRIPTION OF SYMBOLS 11 Brightness measuring apparatus 12 Control apparatus 17 Quick setting agent supply apparatus 18 Water automatic supply apparatus 20 Spray nozzle 21 Belt conveyor 22 Dark place 23 Unit (coating member)
24 LED (light source)
25 Luminance meter 35 Display 51 Control panel

Claims (10)

In a concrete dry spraying system in which a mixture in which cement and aggregate are mixed is conveyed to a spray nozzle and water is supplied from the vicinity of the spray nozzle while spraying the mixture onto a spray surface.
The dry spray system includes a brightness measuring device for measuring a first brightness of the mixture conveyed to the spray nozzle, a plurality of second brightnesses of the prototype mixture measured in advance, and the prototype mixture corresponding to the second brightness. A surface water ratio calculation formula is determined from a correlation with a plurality of surface water ratios, and the surface water ratio of the mixture is calculated by substituting the first luminance of the mixture measured by the luminance measuring device into the surface water ratio calculation formula. The dry spraying system, wherein the control device displays the calculated surface water content of the mixture.   The luminance measuring device outputs the first luminance of the mixture to the control device while measuring the first luminance of the mixture a plurality of times at predetermined intervals within a predetermined measurement time, and the control device A luminance average value and a standard deviation are obtained from a first group of one luminance, and a second group existing within a reliability range determined from the luminance average value and the standard deviation is extracted from the first group, The dry spraying system for concrete according to claim 1, wherein the surface water content of the mixture is calculated by substituting the corrected luminance average value obtained from the second group into the surface water content calculation formula.   In the system, the measurement time of the first luminance can be set in a range of 1 to 15 minutes, and the measurement interval of the first luminance can be set in a range of 2 to 10 seconds. The concrete dry spraying system according to claim 2, wherein the luminance average value and the standard deviation are obtained based on a first group of the first luminances measured in time.   4. The concrete dry spraying system according to claim 2, wherein in the system, the reliability when the second group having the first luminance is extracted can be set in a range of 68.26 to 99.73%. 5. .   The dry spray system includes an automatic water supply device that automatically supplies the amount of water supplied from the control device to the vicinity of the spray nozzle, and the control device is based on the surface water ratio calculation formula. While calculating the water content of the aggregate from the calculated surface water content, subtracting the water content from a preset set water amount to calculate the supply water amount, and outputting the calculated supply water amount to the automatic water supply device The dry spraying system for concrete according to any one of claims 1 to 4.   The brightness measuring device partially covers the mixture moving continuously in one direction to create a dark place, a light source for irradiating light to the mixture moving in the dark place, and a light source irradiated from the light source. A dry spraying system for concrete according to any one of claims 1 to 5, wherein the system is composed of a luminance meter for measuring the first luminance of the mixture illuminated by light. In a concrete dry spraying method of transporting a mixture of cement and aggregate to a spray nozzle, and spraying the mixture onto a spray surface while supplying water from the vicinity of the spray nozzle,
The dry spraying method includes a brightness measurement step of measuring a first brightness of the mixture conveyed to the spray nozzle, a plurality of second brightnesses of the prototype mixture measured in advance, and the prototype mixture corresponding to the second brightness A surface water ratio calculation formula is determined from a correlation with a plurality of surface water ratios, and the first luminance of the mixture measured in the luminance measurement step is substituted into the surface water ratio calculation formula to determine the surface water ratio of the mixture. The said dry-type spraying method characterized by having the surface water rate calculation process to calculate, and the surface water rate display process which displays the calculated surface water rate of the said mixture.   In the luminance measurement step, the first luminance of the mixture is measured a plurality of times at predetermined intervals within a predetermined measurement time, and the measured first luminance is output to the control device. In the surface water content calculation step, Then, a luminance average value and a standard deviation are obtained from the first group of the first luminances, and a second group existing within a reliability range determined from the luminance average value and the standard deviation is extracted from the first group. The dry spraying method for concrete according to claim 7, wherein the surface water ratio of the mixture is calculated by substituting the corrected average brightness value obtained from the second group into the surface water ratio calculation formula.   The dry spray method includes a water automatic supply step of automatically supplying water in the vicinity of the spray nozzle, and in the surface water rate calculation step, the surface water rate is calculated from the surface water rate calculated based on the surface water rate calculation formula. While calculating the water content contained in the aggregate, the water content is calculated by subtracting the water content from a preset water content set in advance, and in the water automatic supply step, the water content calculated in the surface water content calculation step is calculated. The concrete dry-type spraying method according to claim 7 or 8, wherein a water supply amount of water is supplied.   In the luminance measurement step, the mixture moving continuously in one direction is partially covered to create a dark place, and the mixture moving in the dark place is irradiated with light, and the mixture illuminated by the irradiated light. The dry spraying method for concrete according to any one of claims 7 to 9, wherein the first luminance is measured.

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