General-purpose water absorption test device

Abstract

To provide a general-purpose water absorption test device capable of measuring the amount of water absorption of a concrete surface without being affected by the orientation of the concrete surface.SOLUTION: A general-purpose water absorption test device includes a water absorption cup 1 and energizing means for energizing an open surface of the water absorption cup 1 to a concrete surface. The inside of the water absorption cup 1 is partitioned by an elastic membrane 12 into a water chamber 2 on the side in contact with the concrete surface and an air chamber 3 on the opposite side. In a test, the water chamber 2 is filled with water, and the air pressure adjusted by air supply to the air chamber 3 is transmitted to the water in the water chamber 2 through the elastic membrane 12 to adjust the water pressure of the water chamber 2 in contact with the concrete surface.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a general-purpose water absorption tester capable of performing measurements regardless of the orientation of the concrete surface to be measured. [Background technology]

[0002] The Surface Water Absorption Test (SWAT) is known as one of the methods for evaluating the quality of concrete surfaces. As an example, Patent Document 1 discloses the following water absorption test device. A conventional water absorption test apparatus will be described with reference to FIG. 4. The conventional water absorption test apparatus is equipped with a short cylindrical water absorption cup a with one open surface, and a biasing means (not shown) consisting of a pair of negative pressure type suction cups and a fixed frame for attaching the water absorption cup a to a concrete surface c. The water absorption cup a has a water absorption chamber formed on its open side, and a thin tube-shaped cylinder b is erected on the top of the cup so as to communicate with the water absorption chamber. The open surface of the absorption chamber of the absorption cup a is brought into close contact with the surface of the concrete c to be measured, the inside of the absorption chamber is filled with water, and a predetermined water pressure based on the head difference of the cylinder b is applied to the concrete surface c. The method involves calculating and evaluating the rate at which water is absorbed into the concrete surface c by reading the changes in the water level in cylinder b from time to time from immediately after the test. The change in water level in cylinder b can be read visually, but it can also be detected by a water pressure sensor attached to cup a and the amount of change can be calculated. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5880981 Summary of the Invention [Problem to be solved by the invention]

[0004] The conventional water absorption tester shown in Patent Document 1 has the following problems. <1> As shown in Figure 4, measurements are possible when the concrete surface c to be measured is a floor or wall surface, but measurements are not possible when the object to be measured is an upward-facing structure such as a tunnel ceiling surface or the underside of a bridge deck. This is because in such a structure, cylinder b cannot be arranged vertically and the required head difference cannot be ensured. <2> Furthermore, when measuring a floor surface, cylinder b must be attached to the end face of cup a, and when measuring a wall surface, cylinder b must be attached to the side face of cup a, and cylinder b must be reattached every time a measurement is made.

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a water absorption test apparatus capable of solving the above problems. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention provides a water absorption test apparatus comprising a water absorption cup having a bottom and an open side which contacts the concrete surface, and a biasing means for biasing the open side of the water absorption cup against the concrete surface, the inside of the water absorption cup being partitioned by an elastic membrane arranged parallel to the concrete surface to be measured, dividing the inside of the water absorption cup into a water chamber on the side which contacts the concrete surface and an air chamber on the opposite side, a water-permeable plate is provided on the open side of the water chamber of the water absorption cup, and during testing, the water chamber is filled with water, and the air pressure adjusted by supplying air into the air chamber is transmitted to the water in the water chamber through the elastic membrane, making it possible to adjust the water pressure in the water chamber. In still another embodiment of the present invention, an air pressure sensor is disposed in the air chamber so that the air pressure in the air chamber can be detected by the air pressure sensor. In still another embodiment of the present invention, a water pressure sensor is disposed in the water chamber so that the water pressure in the water chamber can be detected by the water pressure sensor. In still another embodiment of the present invention, the water-permeable plate covering the open face of the water-absorbing cup is constructed by laminating a perforated plate arranged on the water chamber side and a water-permeable mesh arranged on the open face side. Effect of the Invention

[0007] The versatile water absorption tester of the present invention can provide the following effects. <1> It is possible to measure the amount of water absorbed by concrete surfaces such as ceilings and the undersides of bridges, and measurements can be made without being affected by the orientation of the concrete surface. <2> Since there is no need to stand a cylinder as in the past, there is no need to attach and detach a cylinder each time the amount of water absorption of the horizontal and vertical surfaces of the concrete is measured, making it possible to perform measurements quickly. <3> To easily and accurately control the water pressure in the water chamber of a water suction cup. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram of an embodiment of a general-purpose water absorption tester according to the present invention. [Diagram 2] An explanatory diagram of the main parts of Figure 1 [Diagram 3] Installation diagram [Figure 4] FIG. 1 is an explanatory diagram of an embodiment of a conventional water absorption test device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] BEST MODE FOR CARRYING OUT THE DISCLOSURE A preferred embodiment of a general-purpose water absorption tester according to the present invention will now be described in detail with reference to the drawings. EXAMPLES

[0010] <1> Overall configuration of a general-purpose water absorption test device. The general-purpose water absorption tester of the present invention comprises a cup 1, a biasing means for pressing the cup 1 against a target surface, a means for supplying water to the cup 1, and a means for supplying compressed air to the cup 1.

[0011] The biasing means for the water-suction cup 1 may be a known attachment mechanism such as a support frame attached to the water-suction cup 1 and a pair of suction cups for attaching the support frame to the concrete surface, or a separator remaining on the poured concrete surface.

[0012] <2> Water absorption cup. The water-absorbing cup 1 is a cylindrical body with a bottom and an open top, like a pot (for ease of understanding, the following description will refer to the top, bottom, sides, etc., assuming that the cup is fixed to a ceiling surface, but this does not limit the position of the cup when in use). The cup 1 has an annular seal 11 on its upper edge, i.e., on its open edge. The annular seal member 11 is made of a material that is elastically compressible and deformable. Therefore, when the cup 1 is pressed against an uneven concrete surface, the sealant 11 deforms to allow the cup 1 to adhere closely to the concrete surface.

[0013] <3> Partition between the water chamber and the air chamber. The internal space of the water-absorbing cup 1 has an elastic membrane 12 arranged horizontally in the middle, functioning as a partition plate, a water chamber 2 is formed on the open side of the elastic membrane 12 in contact with the concrete, and an air chamber 3 is formed on the opposite back side of the elastic membrane 12.

[0014] The elastic membrane 12 is made of a sheet material such as rubber that is waterproof, flexible, and freely deformable.

[0015] In order to maintain the position of the elastic membrane 12 as a partition plate, a perforated support plate 13 having holes is disposed on the lower surface of the elastic membrane 12 . The perforated support plate 13 can be made of, for example, an acrylic plate. The diameter and number of holes formed in the perforated support plate 13 can be appropriately selected. The perforated support plate 13 is not an essential member and may be omitted.

[0016] <4> Water chamber. The water chamber 2 disposed above the water suction cup 1 has its open upper surface closed by a laminate of a perforated plate 21 and a mesh 22 . The perforated plate 21 and mesh 22 arranged in a layered manner allow water to pass through. As the mesh 22, a known woven net made by crossing wires can be used.

[0017] The perforated plate 21 and mesh 22 are used in an overlapping manner so that they work together to cut the surface tension of the water, allowing the water to flow out quickly without leaving any air bubbles between the perforated support plate 13 and the concrete surface. The mesh 22 is a spacing member that forms a gap between the perforated support plate 13 and the concrete surface, and by allowing water to pass through this gap quickly, it is possible to effectively prevent air bubbles from remaining in the water chamber 2.

[0018] A water pressure sensor 23 is installed in the water chamber 2 so that the water pressure inside the water chamber 2 can be detected from the outside.

[0019] The pressurized water in the water chamber 2 permeates through the mesh 22 on the upper surface of the perforated plate 21 installed like a lid and into the surface of the concrete. However, it is necessary to prevent air from accumulating in the pressurized water for the following reasons.

[0020] <5> The reason why air bubbles are not generated in the water chamber. Without the perforated plate 21 and mesh 22 that serve as the lid of the water chamber 2, air bubbles would easily remain between the water chamber 2 and the concrete surface when the remaining water in the water chamber 2 is collected. If air bubbles remain in the water chamber 2, the air bubbles will accumulate on the surface of the concrete being measured, preventing water from spreading evenly and inhibiting the concrete from absorbing water in the areas where the air bubbles have accumulated. As a result, it is not possible to perform an accurate surface water absorption test. Therefore, in the present invention, a combination of a perforated plate 21 and a mesh 22 is adopted, so that air bubbles can be removed at the same time as water is collected.

[0021] <6> Water supply and drainage channels and means of water supply. To supply and drain water to the water chamber 2, a water supply passage P1 and a drain passage P2 are provided in the water chamber 2. The water chamber 2 and an external water supply tank T1 are connected by a water supply passage P1 with a valve, and the water chamber 2 and an external water recovery tank T2 are connected by a drain passage P2 with a valve, so that water supply and drainage can be performed from the water supply passage P1 to the drain passage P2.

[0022] In this example, a water supply means is shown in which compressed air from a pressure pump U is supplied to a water supply tank T1 to supply water to the water chamber 2, but a simple manual injection means such as a syringe can also be used, which is effective for use outdoors where there is no power source.

[0023] The water supply and drainage into the water chamber 2 may be configured to be conducted from the drainage passage P2 toward the water supply passage P1.

[0024] <7> Air chamber. As described above, the air chamber 3 is formed in the lower half of the water suction cup 1. An air pressure sensor 31 is disposed in the air chamber 3 .

[0025] <8> Air supply passage and compressed air supply means. Furthermore, an air supply passage P3 is connected to the air chamber 3. FIG. 1 shows a mode in which compressed air from a pressure pump U is supplied to an air chamber 3 through an air supply passage P3. In short, it is sufficient that the configuration can supply compressed air whose pressure has been adjusted via an external pressure pump U or a manual pump (not shown) or the like into the air chamber 3.

[0026] [Test Method] Next, a method for testing the water absorption of a concrete surface using a general-purpose water absorption test device will be described. In this example, the ceiling surface which could not be measured by the conventional water absorption tester will be described in particular. However, the present invention is not limited to the ceiling surface, and can also perform the water absorption test on floor surfaces, wall surfaces and inclined surfaces.

[0027] <1> Installing the water suction cup. In order to attach the above-mentioned water-absorbing cup 1 to the ceiling surface, for example, a long rod-shaped support frame 4 as shown in FIG. 3 is used. The support frame 4 is attached to the ceiling surface at two points on both ends as fixing points 41, and the water absorption cup 1 is set facing upward between the fixing points 41 so as to be in close contact with the concrete surface. If the fixing point 41 is axially slidable relative to the support frame 4, the position of the fixing point can be freely selected.

[0028] To fix the fixing point 41 to the concrete surface, known methods can be used, such as removing the mortar from the separator cone when pouring the concrete to expose the screw at the end of the separator, or fixing it by applying negative pressure to a cup-shaped suction cup, as described in Patent Document 1.

[0029] By pressing the cup 1 strongly against the concrete surface, the annular seal member 11 on the upper edge of the cup 1 is deformed to form a tight seal.

[0030] As described above, the surface on which the water suction cup 1 is attached may be any surface, such as upward, sideways, downward, or inclined, and the arrangement shown in the figure is merely an example.

[0031] <2> Supplying water to the water chamber. While draining the remaining water in the water chamber 2, the water supply passage P1 from the water supply tank T1 is simultaneously opened to fill the water chamber 2 with pressurized water until it is full. This brings the water in the water chamber 2 into contact with the concrete surface under pressure.

[0032] <3> Air supply to the air chamber. Next, pressurized air is supplied into the air chamber 3 through the air supply passage P3. Then, the pressure in the air chamber 3 increases, displacing the elastic membrane 12 towards the water chamber 2. As the elastic membrane 12 displaces, the water pressure in the water chamber 2 increases and the water permeates the concrete surface.

[0033] This change in water pressure in the water chamber 2 is detected by a water pressure sensor 23, and the air pressure is adjusted so that the water pressure reaches the correct initial water pressure (3 kPa). In this manner, the water pressure in the water chamber 2 can be accurately controlled through pressure control by supplying compressed air to the air chamber 3.

[0034] In particular, since water is an incompressible fluid, it is technically difficult to directly adjust and control the water pressure at low water pressure (3 kPa), but since air is a compressible fluid, it is easy to fine-tune and control the pressure.

[0035] <4> Measuring the amount of water absorbed by a concrete surface. The initial setting is made with the initially applied water pressure (3 kPa) as the zero point. In this state, the pressure change in the air chamber 3 for a predetermined test time is measured by either the air sensor 31 or the water pressure sensor 23 in the water chamber 2, or by both sensors.

[0036] It is also possible to omit the water pressure sensor 23 and perform measurement using only the air sensor 31. In this case, the change in water pressure in the water chamber 2 is perceived as a change in air pressure in the air chamber 3, and the change in water pressure in the water chamber 2 is measured indirectly through the air chamber 3. Moreover, the measurement data of the air sensor 31 may be collated with the measurement data of the water pressure sensor 23 and used in a complementary manner.

[0037] The measured data can also be transmitted to a smartphone or other device via Bluetooth (registered trademark) and displayed.

[0038] Incidentally, the present invention is directed to a general-purpose water supply test device for measuring the amount of water absorption of a concrete surface, and since the measuring method is widely known, a more detailed explanation will be omitted.

[0039] [Effects of the embodiment] <1> Since it does not use a cylinder as in conventional water absorption test devices, it is possible to measure the concrete surface not only downward and sideways but also upward. Therefore, it is now possible to conduct water absorption tests on upward facing surfaces such as the ceiling surface of a tunnel or the underside of a bridge deck, which was previously not possible. <2> Since this device does not use a cylinder as in conventional testing devices, it is possible to perform measurements quickly because there is no need to change the cylinder installation depending on whether the concrete measurement surface is horizontal or vertical. <3> It is technically difficult to directly adjust water pressure, but the present invention is configured to detect changes in water pressure as changes in air pressure, making it possible to accurately manage the pressure in the water chamber. Therefore, the amount of water absorbed into the concrete surface can be accurately determined. <4> By using a combination of a perforated plate and mesh, the surface tension of the water can be effectively cut at the start of measurement, allowing air bubbles to be quickly expelled to the outside. [Explanation of symbols]

[0040] 1: Water absorption cup 2: Water room 3: Air chamber 23: Water pressure sensor 31: Air pressure sensor

Claims

1. A general-purpose water absorption test apparatus comprising a water absorption cup having a bottom structure with an open side that contacts a concrete surface, and a biasing means for biasing the open surface of the water absorption cup against the concrete surface, The inside of the water suction cup is partitioned by an elastic membrane to separate a water chamber on the side in contact with the concrete surface and an air chamber on the opposite side, a water-permeable plate is provided on an open surface of the water chamber of the water suction cup; During the test, the water chamber is filled with water, The air pressure adjusted by supplying air to the air chamber is transmitted to the water in the water chamber through an elastic membrane, thereby enabling adjustment of the water pressure in the water chamber. General purpose water absorption testing device.

2. 2. The general-purpose water absorption testing apparatus according to claim 1, further comprising an air pressure sensor disposed in said air chamber so as to detect the air pressure in said air chamber.

3. 2. The versatile water absorption test apparatus according to claim 1, further comprising a water pressure sensor disposed in said water chamber so as to detect the water pressure in said water chamber.

4. 2. The versatile water absorption tester according to claim 1, characterized in that the water-permeable plate covering the open surface of said water absorption cup is constructed by laminating a perforated plate arranged on the water chamber side and a water-permeable mesh arranged on the open surface side.

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