JP6440490B2 - Permeability measurement method and measuring device for drainage pavement - Google Patents

Description

  The present invention relates to a water permeability measurement method and a measurement apparatus for a drainage pavement.

  The drainage pavement allows water on the surface to rapidly permeate downward and guide it from a water-impervious layer of a certain depth to the side ditch of the road. This has the effect of reducing slip accidents on the surface and the hydroplaning phenomenon, reducing water splashing on pedestrians, and reducing noise, and has been widely used in recent years. It differs from the so-called permeable pavement that allows all rainwater to permeate downward depending on the presence or absence of a water shielding layer.

  Thus, in drainage pavements, the impervious layer plays an important role in preventing the water that has permeated from the surface of the pavement from penetrating into the layers below the base layer. The water function is lost, and various problems such as cracks and pumping occur due to water penetrating downward.

  Moreover, the water permeable layer which is a surface layer naturally has many voids due to its function, and therefore, the adhesive strength of the aggregate is weak. Therefore, the aggregate is apt to be scattered by the traffic of the car. Further, once the aggregate is scattered, the portion is more exposed and the scattering occurs at an accelerated rate.

  As a method for preventive repair of such drainage pavement, a method of spraying a liquid repair material such as asphalt emulsion from the road surface has been proposed. This method is advantageous in many respects, such as the formation of a water-blocking layer on the base layer and the suppression of aggregates on the pavement surface layer at a lower cost compared to general cutting overlays on the pavement surface layer. It is the method which has.

  At the time of construction, a liquid repair material such as asphalt emulsion is sprayed on the road surface with a spreader such as a distributor to penetrate into the voids in the surface layer. At that time, in order to form a water shielding layer between the surface layer and base layer of the drainage pavement, which is one of the purposes, it is necessary to spray the required amount of liquid repair material per unit area. Roads that have passed through the moon gradually become clogged and often do not maintain the porosity when paved. If the liquid repair material is sprayed on the drainage pavement surface clogged in this way, the liquid repair material does not permeate the inside of the space and stays on the road surface, and in some cases, flows out of the construction section along the road surface gradient.

  In order to prevent these problems, it is necessary to conduct a preliminary survey before actual construction, measure the water permeability of the surface layer portion, and investigate the degree of clogging of the gap.

  The conventional method for this investigation is to measure water permeability by a method using an on-site water permeability tester as shown in FIG. In this conventional method, the water stored in the container 1 flows down to the reverse funnel-shaped watering container 4 through the lower pipe 2 and the valve 3 provided therein, and is integrated with the water in the container 1. Infiltrate from the road surface that touches. Since the reverse funnel-shaped container 4 is a closed system, pressure (water head pressure) due to the water column of the container 1 is applied, and the conditions are different from the open atmosphere conditions where the liquid repair material or the like is actually sprayed. In other words, it is still unclear what kind of relationship is there between water permeability and this water head pressure and in what conversion it can be converted. In addition, the area of the road surface in contact with the inverted funnel-shaped container is small, and the measurement error due to the difference in measurement place is large.

  As another method, there is a method of estimating the water permeability by examining the porosity by sound reflection without actually infiltrating water, but it is an indirect method, and it is a direct correlation with respect to the water permeability to be obtained. Cannot be obtained.

  Therefore, a measurement method and a measurement apparatus that can easily measure the water permeability of a drainage pavement and that have a correlation with the case of asphalt emulsion spraying by an actual distributor or the like are provided.

In view of the situation as described above, the present inventor has completed the drainage pavement permeability measurement method and measurement device according to the present invention as a result of earnest research, and the feature thereof is the measurement method. In that case, on the drainage pavement surface, a certain area of the road surface is surrounded by a frame body under the open air condition, and at least 1.5 L / m ² or more of water is uniformly sprayed within 3 seconds, and the spraying is completed. From the point that water permeability is measured by measuring the time until almost all the spray water except the one adhering to the coarse aggregate surface is absorbed by the coarse aggregate voids observed on the pavement surface. Yes, in the measuring device, on the drainage pavement surface, under a condition of opening to the atmosphere, a certain area of the road surface is surrounded by a frame body, and at least 1.5 L / m ² or more of water is uniformly distributed within 3 seconds. Disperse and remove any deposits on the surface of the coarse aggregate from the completion of application. This is a device for measuring the time until almost all of the spray water is absorbed by the coarse aggregate voids observed on the pavement surface. The enclosure defines the area to be sprayed, and the sprinkled water is outside the enclosure. Side leakage prevention material that prevents leakage of water, a spreader box that serves as a water storage part and a water spout for spraying a certain amount of water, a water stop pad that serves as a closure for the water spout of the spreader box, and for movement of the spreader box It is in the point which has a guide rail.

First, the water permeability measurement method of claim 1 of the present invention will be described.
The open air condition means that the water to be sprinkled is open to the atmosphere and sealed and not pressurized. This eliminates the drawbacks of the conventional measurement described above.

The area to be measured is surrounded by a frame, and at least 1.5 L / m ² or more of water is sprayed in it within 3 seconds. If it is 1.5 L / m ² or less, the liquid level is too small to be easily understood. Although many may be sufficient, 5 L or less is preferable on measurement operation, More preferably, it is 3 L or less.

  Apply within 3 seconds. It is sufficient if it can be sprayed simultaneously in the area surrounded by the frame, but it is within 3 seconds because it is actually difficult. This is because if it takes 3 seconds or more, the first sprayed portion will penetrate and a measurement error will occur. Preferably it is 0.5 to 2 seconds.

  Uniform here means that the entire area surrounded by the frame is uniform, but it is not uniform in a mathematically exact sense, and there is no difference in spraying amount of more than 10% over any part. It means degree. If the amount is partially different, correct measurement cannot be performed.

  The coarse aggregate observed on the pavement surface is a coarse aggregate that can be seen from the surface, and is generally an aggregate that comes into contact with an automobile tire. In exceptional cases, there may be scattered surface aggregate and the underlying aggregate may be visible, but such lower aggregate is not included here.

  The time when the sprayed water is absorbed in the voids of the coarse aggregate observed on the pavement surface described above refers to the point in time when the sprayed water is absorbed by the spaces after the completion of the spraying and becomes invisible. However, adsorbed water adhering to the aggregate surface is excluded.

  The time from the completion of spraying to the above absorption is basically measured visually. It is easy to measure with a stopwatch. Alternatively, the clock may be automatically started from the time when watering is completed, and the clock may be stopped by pressing a button.

  Specimens for drainage pavement with different water permeability as a method for judging whether or not liquid repair materials such as asphalt emulsion will rapidly penetrate into the drainage pavement in the repair method where liquid repair material is sprayed and penetrated. To determine the correlation between the time required for the above water permeability and the permeability of the actual liquid repair material sprayed. In addition, after spraying a certain amount of liquid repair material, check the water penetration time in the specimen so that the liquid repair material does not penetrate quickly and stay on the road surface. It is also possible to judge that construction is possible if the water permeation time is short and impossible if it is long.

Next, an apparatus according to claim 2 will be described.
The apparatus of the present invention is for carrying out the method of claim 1 and includes an enclosure frame, a side leakage prevention material, a spreader box, a water stop pad, and a guide rail.

Here, the enclosure frame is a rectangular frame, and determines the watering range primarily. That is, it is placed on the pavement surface to be measured and surrounds the area where water is sprayed.
The size of the surrounding frame is about 20 to 50 cm in both vertical and horizontal directions, and preferably about 30 to 40 cm.

  The side leakage preventing material serves as a seal that prevents the sprayed water from leaking out from the range of the surrounding frame. It is fixed to the lower side or the side part of the side leakage preventing material, or is detached every time. In order to require hermeticity, it must be a flexible material. These are plastics such as rubber, soft plastic and clay.

  The spreader box is a tank for storing water to be sprinkled. From this tank, a certain amount of water can be sprayed as uniformly and rapidly as possible on the surface to be measured. For example, a long box having the same length as the horizontal width (or vertical width) of the inner surface of the surrounding frame and having a slit having the same length below is preferable. The shape of the slit is not limited, but a slit devised with a perforated plate, a partition plate or the like is preferable for uniform dispersion. Water falls when the slit part is separated from the water stop pad.

  The capacity of the spreader box is not limited, but is preferably about 300 mL to 1 L. The spreader box preferably has a width that narrows downward. And what has a slit in the front-end | tip part is good.

  The water stop pad closes the watering opening of the above-described spreader box, and includes a lid, a cover, padding, and the like. In short, it is usually only necessary to be able to open quickly when closing and measuring. When the opening is a slit, it may be a long lid or a rod made of a flexible material such as rubber. The opening method is such that the rod is removed or water is sprayed when the spreader box is moved from the closure.

  Further, the opening may be performed by opening a lid (water stop pad) at the same time as the spreader box is moved by a wire from a spreader box drive motor described later.

  A level can be attached to the spreader box to confirm the level. Furthermore, a mechanism that is always kept horizontal may be provided. For example, a mechanism that can rotate freely back and forth and left and right, and is always horizontal due to gravity.

  The spreader box may be moved by hand or may be moved by a motor. This is to keep the speed constant. If the speed of spraying is not constant, the spraying amount will vary depending on the location, resulting in a measurement error. The method of movement is free, such as pulling with a wire connected to the motor or moving by rotating the gear.

  The completion of watering is the time when watering is stopped. Stopping the watering may be performed by closing the opening of the watering when the above-described spreader box is stopped, or may be stopped when the spreader box is stopped by adding a predetermined amount of water from the beginning.

  The guide rail is an auxiliary tool for quickly moving the spreader box over the entire water spray area. The spreader box moves on this rail and sprinkles water. Therefore, the rail does not need to be special and may be a normal one.

The guide rail is preferably adjustable in angle.
The pavement surface that is the surface to be measured is not always horizontal. If there is an inclination and the water is disregarded, the spreader box is inclined and the water cannot be uniformly distributed. Therefore, if the angle of the guide rail can be adjusted, the advancing direction of the spreader box becomes horizontal. Moreover, what is necessary is just to adjust the angle of a spreader box for the direction at right angles to the advancing direction of a spreader box. With this, the angle can be adjusted with respect to all directions, and the pavement surface can be kept horizontal regardless of the direction of inclination.

The present invention has the following effects.
(1) Since the water is sprinkled in the open atmosphere, it is possible to measure the penetration rate close to actual.
(2) Since the water can be sprinkled quickly, the measurement is accurate.
(3) Since leveling can be secured, water can be sprayed more uniformly.

1 is a schematic plan view of an example of the water permeability measuring device 1 of the present invention. 1 is a schematic side view of an example of the water permeability measuring device 1 of the present invention. 1 is a schematic perspective view of an example of the water permeability measuring device 1 of the present invention. It is sectional drawing of a prior art example.

Hereinafter, the present invention will be described in more detail based on embodiments shown in the drawings.
FIG. 1 shows an example of the water permeability measuring device 1 of the present invention, and is a schematic plan view partially omitted. The enclosure 2 and the spreader box 3 are visible. The spreader box 3 sprays water while proceeding in the direction of arrow A. An area 4 surrounded by the watering surface surrounding frame 2 is a surface to be measured.

  FIG. 2 is a side sectional view of FIG. It can be seen that there is a side leakage prevention material 5 below the enclosure frame 2 and is placed on the pavement surface. In this figure, the spreader box 3 sprinkles water in the direction of arrow C while proceeding in the direction of arrow B. In this figure, the state in which water 6 entered after watering is shown. Thus, the time from when the constant water is sprayed (dispersion is completed) to when the sprayed water is absorbed into the voids of the coarse aggregate where the measurement area is observed is measured to obtain the permeation time.

  FIG. 3 is a specific diagram of an example of the present apparatus. A guide rail 7 is attached to the enclosure frame 2 so that the angle can be adjusted. The fixing lever 8 is loosened, the angle is adjusted, and the fixing lever 8 is tightened again. A wire 9 is attached to the spreader box 3 and pulled by a front motor 10.

  The spreader box 3 is supported by the frame 11 and can be adjusted in angle. A rotation angle adjusting device 12 is provided at the center. In addition, a level 13 is attached to the upper part. Below the spreader box 3, there is a slit (not shown) from which water is sprayed. This slit is located on the water stop pad for closing, and when the spreader box 3 moves, the water stop pad is removed from the slit and sprays water.

  Start the stopwatch as soon as the watering is completed, and stop the stopwatch when the water level is absorbed by the coarse aggregate voids on the surface of the measurement area and disappears. This completes the measurement.

DESCRIPTION OF SYMBOLS 1 Permeability measuring device 2 Enclosure frame 3 Spreader box 4 Enclosed area 5 Water stop pad 6 Water 7 Guide rail 8 Fixing lever 9 Wire 10 Motor 11 Frame body 12 Rotation angle adjustment device 13 Level

Claims (3)

On a drainage paved road surface, a certain area of the road surface is surrounded by a frame body under open air conditions, and is a long box with the same length as the horizontal width (or vertical width) in the frame, and the same length downward Spread at least 1.5 L / m ² or more of water from the spreader box with slits within 3 seconds within 3 seconds. A method for measuring water permeability of a drainage pavement characterized by measuring the water permeability by measuring the time until the spray water is absorbed by the coarse aggregate voids observed on the pavement surface. On a drainage paved road surface, a certain area of the road surface is surrounded by a frame body under open air conditions, and is a long box with the same length as the horizontal width (or vertical width) in the frame, and the same length downward Spread at least 1.5 L / m ² or more of water from the spreader box with slits within 3 seconds within 3 seconds. This is a device for measuring the time until the spray water is absorbed by the coarse aggregate voids observed on the pavement surface. The enclosure frame defines the area to be sprayed, and the sprayed water leaks outside the enclosure frame. Water-permeable permeability of a drainage pavement characterized by having a side leakage prevention material for preventing water, the spreader box, a water stop pad that is a stopper for a water spray port of the spreader box, and a guide rail for moving the spreader box measuring device.   The water permeability measuring device for a drainable pavement according to claim 2, wherein a level is attached to the spreader box, and the spreader box has a mechanism that keeps the spreader box always horizontal.

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