JP2023031572A - Method for predicting use amount of self-leveling material - Google Patents

Abstract

To provide a method for predicting a use amount of a self-leveling material prior to finishing work to correct the unevenness of an underfloor surface using the self-leveling material.SOLUTION: A method for predicting a use amount of a self-leveling material to be constructed on a base surface 10, comprises: a marker installation step of installing at least three markers 20 at the same height on or around the base surface so as not to be aligned in a straight line; a three-dimensional measurement step of acquiring a three-dimensional shape of the base surface and three-dimensional coordinates of the marker; a step of setting a planned finished surface parallel to a horizontal surface above the base surface based on the three-dimensional coordinates of the marker; and a step of calculating a predicted use amount of the self-leveling material based on the planned finished surface and the three-dimensional shape of the base surface.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for predicting the amount of self-leveling material used to level a floor subfloor.

Since the surface of a floor slab or the like has unevenness such as unevenness and slopes to some extent, it is finished to a horizontal surface by applying a surface conditioning material such as mortar on the surface.

In Patent Document 1, a reference board with a known surface height is installed around a floor made of a structure such as a concrete slab, and the three-dimensional shape data of the surface of the reference board and the surface of the structure are obtained as a plurality of data. A method for measuring the uneven shape of the floor surface is described by acquiring measurement points and measuring the height of the surface of the structure with reference to a virtual plane including the surface of the reference board. Then, it is described that the shape of the surface of the concrete structure is corrected based on the measurement results.

In Patent Document 2, a plurality of reference points with known separation distances are set around the upper surface of an area where concrete is to be placed, and the reference points are captured in images taken from two different positions. Identify each shooting position from the position of the point, pour concrete and level the top surface, shoot the top surface of the poured concrete from two different positions, calculate the height of the top surface from the image and plan A method for contrasting finished height is described. Further, it is described that the efficiency and accuracy of the finishing work are improved by displaying the height of the upper surface relative to the planned finish height in a recognizable manner.

On the other hand, in recent years, substrate conditioning materials with excellent self-leveling properties called levelers, leveling materials, self-leveling materials, etc. (in the present invention, these are collectively referred to as "self-leveling materials" and hereinafter abbreviated as "SL materials"). is sometimes used. The SL material is highly fluid, and has the advantage of forming a smooth horizontal surface by simply pouring the slurry onto the underlying surface and leveling it with a dragonfly or the like. In addition, the SL material has a short drying time and can walk on the construction surface after curing for several hours, so it has the advantage of shortening the construction period.

JP 2021-060317 A JP 2016-151113 A

Although the SL material has the above-described features, it is expensive, so it is desirable to avoid wasting the excess slurry prepared by kneading the raw material powder with water as much as possible. On the contrary, if the amount of slurry is insufficient, it is not easy to prepare additional slurry and apply it to the construction surface because of the short drying time. For this reason, in finishing work using SL materials, it is required to predict the amount required for the work as accurately as possible before construction.

Patent Documents 1 and 2 describe a method for 3-dimensionally measuring the uneven shape of the base surface to visualize unevenness and improve the efficiency of finishing work on a horizontal surface. No method for estimating usage is provided.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for estimating the amount of SL material to be used prior to finishing work for correcting unevenness of the underfloor surface using SL material. do.

A self-leveling material usage prediction method of the present invention is a method for predicting the usage of a self-leveling material to be applied to a base surface, wherein at least three markers are placed at the same height on or around the base surface. a step of placing markers so as not to line up in a straight line; a step of three-dimensional measurement of obtaining a three-dimensional shape of the base surface and three-dimensional coordinates of the markers; and a step of three-dimensional measurement of the base surface based on the three-dimensional coordinates of the markers setting a planned finished surface parallel to the horizontal plane above the , and calculating a predicted usage amount of the self-leveling material based on the three-dimensional shapes of the planned finished surface and the base surface.

Here, that the height of the marker is the same means that the position in the vertical direction in the world coordinate system is the same, not the height from the base surface. A horizontal plane is a plane perpendicular to the direction of gravity.

Another self-leveling material usage prediction method of the present invention is a method of estimating the usage amount of a self-leveling material to be applied to a base surface, using a three-dimensional measuring instrument capable of detecting the inclination from the horizontal, A three-dimensional measurement step of obtaining a three-dimensional shape of the base surface and setting a reference horizontal plane; a step of setting a planned finish surface above the base surface parallel to the reference horizontal surface; and calculating a predicted usage of the self-leveling material based on the three-dimensional shape of the ground.

By using any of the self-leveling material usage prediction methods of the present invention, the predicted usage amount of the self-leveling material can be calculated prior to the construction work of the self-leveling material, so construction can be performed with the minimum necessary materials. , the material cost can be reduced. In addition, the height of the finished surface can be made uniform with respect to a plurality of base surfaces.

It is a figure which shows the structure of the apparatus for enforcing the usage-amount prediction method of the self-leveling material of 1st Embodiment. FIG. 2 is a process flow diagram of a self-leveling material usage amount prediction method according to the first embodiment. A and B: Examples of markers used in the self-leveling material usage prediction method of the first embodiment. It is a figure for demonstrating the relationship between a base surface, a reference horizontal surface, a planned finish surface, and interior reference height in the usage-amount prediction method of the self-leveling material of 1st Embodiment. FIG. 7 is a process flow diagram of a self-leveling material usage amount prediction method according to the second embodiment. FIG. 10 is a diagram for explaining a three-dimensional measurement process by a fixed three-dimensional measuring device in the self-leveling material usage amount prediction method of the second embodiment. 8A and 8B are diagrams for explaining a three-dimensional measurement process by a portable three-dimensional measuring device in the self-leveling material usage amount prediction method of the second embodiment; FIG.

A first embodiment of the self-leveling material (SL material) usage prediction method of the present invention will be described with reference to FIGS. 1 to 4. FIG. In this embodiment, a marker is placed on or around the underlying surface to be constructed.

Referring to FIG. 1, the base surface 10 is, for example, cast concrete or a floor slab. The method of this embodiment is performed using the marker 20 and the three-dimensional measuring device 40. FIG. A laser marking device 30 is used for height adjustment of the marker 20 . The calculation unit 43 uses the measurement result of the three-dimensional measuring device 40 to perform various calculations such as setting of a reference horizontal plane, setting of a planned finish plane, and calculation of predicted usage. A recording unit 44 records various data. The details of each device will be described in the description of each step below.

The SL material usage amount prediction method of the present embodiment will be described along the process flow shown in FIG.

(S1) A marker 20 is installed. The marker 20 will be used in later steps to set a virtual reference horizontal plane based on its three-dimensional coordinates. Therefore, the markers 20 are placed on or around the base surface 10, at least three at the same height and not all aligned. Here, that the height of the marker is the same means that the position of the marker in the vertical direction in the world coordinate system is the same, not the height from the base surface of the marker. Similarly, simply referring to "height" in this specification refers to height based on the world coordinate system.

Various arithmetic operations using the three-dimensional coordinates of the marker 20 are actually performed by selecting one point included in the marker as a representative point of the marker and using the three-dimensional coordinates of that representative point. Hereinafter, in this specification, simply referring to the three-dimensional coordinates and height of a marker means the three-dimensional coordinates and height of a representative point of the marker.

Although the shape of the marker 20 is not particularly limited, it preferably has a flat upper surface. By adjusting the plane horizontally using one point on the plane as a representative point, it is possible to reduce the error in the height direction that accompanies the measurement of the three-dimensional coordinates of the marker. Moreover, the shape of the marker 20 is more preferably a flat surface with a square, rectangular, rhombic or circular top surface. If the center of this plane is the representative point of the marker, the representative point can be easily and accurately recognized by taking the intersection of two diagonal lines or the midpoint of the major axis of the observed ellipse during three-dimensional measurement. be able to. FIG. 3A shows a preferred example in which the marker 20 is disc-shaped and the center of the circle on the top surface is the representative point 20C.

Referring to FIG. 3A, marker 20 is supported by base 21 . It is preferable to use a base 21 whose horizontal and height can be adjusted, and for example, a tripod can be used. Referring to FIG. 3B, marker 20 may be placed while floating on the surface of liquid 25 held in transparent container 24 . Thereby, the upper surface of the marker 20 can always be kept horizontal regardless of the inclination of the base surface 10 and without adjusting the horizontality of the base 22 .

Returning to FIG. 1, the heights of the markers 20 are adjusted to be the same. The height of the marker is adjusted so that the vertical position in the world coordinate system becomes the same as described above. It is not necessary to align the heights of the markers 20 to a specific value, and as long as the heights of the multiple markers 20 are the same, the heights may be arbitrary. Adjustment of the height of the marker 20 can be performed by a known method using a known device such as a transit or a theodolite. Preferably, the laser marker 30 is used to adjust the height of all markers 20 to be the same. The use of the laser marking device 30 makes it possible to irradiate a horizontal line in the entire circumferential direction of the device, thus facilitating the work of aligning the heights of the plurality of markers 20 .

As described above, the number of markers 20 should be three or more. When the base surface 10 to be constructed is wide, it is preferable to install more markers so that the markers 20 are scattered over the entire base surface. This is because the displacement of the base surface 10 from the horizontal plane is obtained by comparison with the three-dimensional coordinates of the marker 20, so that the closer the distance to the marker in the base surface, the smaller the measurement error.

(S2) Using the three-dimensional measuring device 40, the three-dimensional shape of the base surface 10 and the three-dimensional coordinates of the markers 20 are acquired. When a display such as a marking line indicating the interior reference height 13, which will be described later, is drawn on the surrounding walls or pillars, the three-dimensional shape of the display is also obtained at the same time.

The method of expressing the three-dimensional shape is not particularly limited as long as it can be processed by a computer. Preferably, a set of three-dimensional coordinates (point cloud data) is used. Since the measurement result by the three-dimensional measuring instrument 40 is obtained as a set of three-dimensional coordinates of a plurality of points on the base surface 10 according to the resolution of the measuring instrument 40, etc., this point cloud data can be used as it is to obtain the three-dimensional coordinates of the base surface. It can be used as a shape.

The format of the three-dimensional measuring instrument 40 is not particularly limited, and various devices such as LiDAR system and stereo system can be used. If a stereo system is employed, preferably an active stereo system device is used. In the active stereo system, one of the two cameras in a normal stereo camera (passive stereo system) is replaced with a projector. A pattern of straight lines or geometric figures is projected from the projector onto the target surface and captured by the camera. In this method, the distance to each measurement point on the pattern is obtained by the principle of triangulation. The active stereo three-dimensional measuring instrument 40 shown in FIG. to find the distance to the measurement point. By scanning the base surface 10 with a laser in the LiDAR method, and by projecting a pattern onto the base surface 10 in the active stereo method, highly accurate three-dimensional measurement is possible even if the base surface 10 does not have a characteristic pattern. becomes.

The three-dimensional measuring instrument 40 may be a fixed type that is fixed in one place in the work place and measures the entire base surface, or it is possible to measure while moving the measuring instrument by holding it by hand. It may be portable. An example of a fixed type is the FARO Technologies, Inc., which is equipped with a LiDAR rangefinder and has a horizontal reference. and laser scanners manufactured by Examples of the portable type include the F6 series manufactured by MantisVision, which employs an active stereo system.

As the three-dimensional measuring instrument 40, a portable type that is easy to handle is preferably used. The portable three-dimensional measuring instrument is moved along the base surface while maintaining an appropriate distance from the base surface 10, performs three-dimensional measurement for each portion of the base surface, and combines the obtained three-dimensional shapes. By doing so, the three-dimensional shape of the entire base surface 10 is obtained. With a fixed 3D measuring instrument, the accuracy of measurement in an area far from the 3D measuring instrument fixed in one place decreases, whereas with a portable 3D measuring instrument, the distance between the measuring instrument and the measurement area decreases. Since it does not change greatly, the entire area of the underlying surface can be measured with a certain degree of accuracy. When the base surface 10 is wide, it is particularly preferable to use a portable three-dimensional measuring device because the overall inclination of the base surface greatly affects the amount of SL material used. When using a portable three-dimensional measuring device, it is preferable to arrange the markers so that one or more markers 20 are always included in the "field of view" of the measuring device, which is a measurable area.

(S3) Referring to FIG. 4, the reference horizontal plane 11 is set based on the three-dimensional coordinates of the marker 20. FIG. Since all markers 20 have the same height, the plane passing through all markers is horizontal. The reference horizontal plane can be set to a horizontal plane passing through the marker or a horizontal plane at an arbitrary height parallel to the horizontal plane. Even if only the three-dimensional shape of the base surface 10 is acquired, the relative positional relationship between the base surface and the horizontal plane cannot be known, and for example, the inclination of the three-dimensional shape of the base surface from the horizontal cannot be known. However, in this embodiment, since the three-dimensional shape of the base surface 10 and the three-dimensional coordinates of the markers 20 are simultaneously obtained in the previous three-dimensional measurement step (S2), the three-dimensional shape of the base surface 10 and the reference It is possible to know the relative positional relationship with the horizontal plane.

(S4) A planned finish plane 12 is set parallel to the reference horizontal plane 11. FIG. The planned finished surface 12 is the finished surface after the SL material is applied. In some cases, the planned finish surface must be set to a predetermined height in relation to the interior finish later, and in other cases, it can be set to a height that is not particularly limited.

In construction work, it is often the case that the height of the floor surface after finishing the interior is determined as several millimeters from the upper surface of the slab in the blueprint. In that case, it is necessary to set the planned finished surface 12 of the SL material to a predetermined height accordingly. In other words, the origin of the world coordinate system should be taken at the slab top surface of the design drawing, and the height of the planned finished surface should be adjusted to a predetermined value in that coordinate system. The absolute value of the height of the reference horizontal plane 11 in world coordinates is unknown. However, if the distance from the slab, etc. on the blueprint is specified for the interior finish, the standard interior height 13, such as the marking line on the wall or pillar, should be 1 m above the top surface of the slab on the blueprint. , the planned finish surface 12 can be set as a surface having a predetermined height difference L from the interior reference height 13 .

On the other hand, if the planned finished surface 12 can be set freely without any particular restrictions, the planned finished surface can be set so as to reduce the amount of SL material used. The standard coating thickness of the SL material is about 10 mm, but the recommended range of coating thickness for each SL material product is defined as, for example, 5 to 20 mm. The planned finished surface 12 can be set so that the distance t1 from the highest peak of the base surface 10 to the planned finished surface 12 is the minimum recommended coating thickness. Since the height of the unevenness of the base surface 10 is usually smaller than the recommended range of the coating thickness, this causes the distance t2 from the lowest valley of the base surface to the planned finished surface to exceed the maximum value of the recommended coating thickness. It is extremely rare. If the distance t2 from the lowest valley of the base surface 10 to the planned finish surface 12 exceeds the maximum value of the recommended coating thickness, it is not preferable to apply the SL material directly to the base surface. The unevenness of the ground is corrected to be small, and the SL material is applied thereon.

(S5) Calculate the estimated amount of SL material to be used from the three-dimensional shapes of the planned finished surface 12 and the base surface 10 . Specifically, the calculating unit 43 calculates the predicted usage amount of the SL material by accumulating the distance t between the planned finished surface 12 and the base surface 10 over the entire base surface 10 . When the three-dimensional shape of the base surface 10 is represented by point cloud data, the density of the point cloud (the area of the area covered by one point) is considered, and the distance from each point to the planned finished surface 12 is integrated. Thus, the predicted amount of SL material to be used can be calculated. Alternatively, the average value (average thickness) of the distance t over the entire base surface 10 may be obtained, and the predicted usage amount of the SL material may be calculated by multiplying this average thickness by the area of the base surface.

Through the steps S1 to S5 described above, the SL material usage prediction method of the present embodiment is completed.

(S6) SL material is prepared and constructed. The type of SL material is not particularly limited, and may be, for example, cement-based or gypsum-based. The quality of the SL material complies with the quality standards for self-leveling materials (JASS15M-103) of the Architectural Institute of Japan.

When the marker 20 is placed on the base surface 10 in the marker placement step (S1), the marker is removed at some stage after the end of the three-dimensional measurement (S2) and before this step. Preparation and coating of the SL material are performed by known methods. For example, the base surface 10 is cleaned, a primer is applied as necessary, raw material powder of the SL material is kneaded with water to prepare a slurry of an expected amount to be used, and the slurry is pumped with a hose to the base surface. Pour into and cure by simply leveling with a dragonfly or the like. When it becomes possible to walk lightly on the SL material, inspect the finished surface for defects.

(S7) Record various data. For example, the recording unit 44 records the measurement result of the three-dimensional shape of the base surface 10, the prediction result of the amount of SL material used, the amount of SL material actually used, and the like. The structure and installation location of the recording unit 44 are not particularly limited, and the recording unit 44 may be, for example, a secondary storage device such as a hard disk device connected to the calculation unit 43, or may be connected to the calculation unit 43 by wire or wirelessly. It may be a server on the Internet that is The recorded data can be used for quality assurance of finishing work using SL materials. For example, construction managers can check whether the required amount of expensive SL materials is properly used.

Next, a second embodiment of the SL material usage prediction method of the present invention will be described with reference to FIGS. 5 to 7. FIG. This embodiment uses a three-dimensional measuring instrument capable of simultaneously detecting the distance and direction to the measurement point, and is implemented without installing markers of uniform height. Note that the same reference numerals are used for the same elements as in the first embodiment, and the description thereof is omitted.

FIG. 5 shows a process flow of the SL material usage amount prediction method of the present embodiment. The marker placement step (S1 in FIG. 2) in the first embodiment is not performed.

(S2A) A three-dimensional shape of the base surface 10 and the position of the reference horizontal plane 11 are acquired using a three-dimensional measuring instrument capable of simultaneously measuring the distance and direction to the measurement point. The three-dimensional measuring instrument may be fixed or portable.

Referring to FIG. 6, as the fixed three-dimensional measuring device 45, for example, a total station equipped with a horizontal reference and a ranging function such as LiDAR can be used. A fixed three-dimensional measuring device 45 is installed horizontally around the base surface 10 . Since the three-dimensional measuring instrument 45 can simultaneously measure the distance d and the direction (θ, φ) to the measuring point T, the three-dimensional coordinates (x, y, z) can be obtained, and the three-dimensional shape of the underlying surface can be obtained by scanning the entire underlying surface 10 . Further, by setting a horizontal plane passing through the three-dimensional measuring device 45 as the reference horizontal plane 11, it is possible to know the relative positional relationship between the three-dimensional shape of the base surface 10 and the reference horizontal plane.

Referring to FIG. 7, when using a portable three-dimensional measuring instrument 46, while maintaining an appropriate distance from the underlying surface 10, the measuring instrument 46 is moved along the underlying surface, and each portion of the underlying surface is measured. , and by connecting the obtained three-dimensional shapes, the three-dimensional shape of the entire base surface 10 is acquired. Since the three-dimensional measurement is performed while moving the three-dimensional measuring device 46, the relative positional relationship with the horizontal cannot be known only by acquiring the three-dimensional shape of the base surface 10. FIG. Therefore, the portable three-dimensional measuring instrument 46 of this embodiment needs to have a function capable of detecting the orientation of the measuring instrument itself. As such a three-dimensional measuring instrument 46, for example, a portable terminal equipped with a gyro sensor and a LiDAR function, an active stereo measuring instrument equipped with a gyro sensor, or the like can be used.

Referring to FIG. 7A, when the distance and direction from position M1 where three-dimensional measuring instrument 46 is located to measurement point T1 are measured, the measurement result is obtained based on position M1 and the attitude of measuring instrument 46 at that time. . Specifically, the distance is the distance d between M1 and T1, and the direction is the angle of displacement from the reference direction Z of the measuring instrument 46 . Similarly, when the three-dimensional measuring device 46 measures the distance d and the direction from another position M2 to the measuring point T2, the measurement result is obtained based on the position M2 and the attitude of the measuring device 46 at that time. If the movement path from the position M1 to M2 and the change in attitude of the measuring instrument 46 are obtained by a gyro sensor or the like incorporated in the three-dimensional measuring instrument 46, the measurement results from the positions M1 and M2 are obtained by the measuring instrument 46 at the position M1. Alternatively, it can be converted to data based on when it is in M2. By setting a horizontal plane whose height is equal to M1 or M2 as the reference horizontal plane 11, the relative positional relationship between the three-dimensional shape of the base plane 10 and the reference horizontal plane 11 can be obtained.

Alternatively, referring to FIG. 7B, if the movement path and attitude of the three-dimensional measuring device 46 cannot be directly obtained, the measurement results from different positions for the same measurement point can be used to determine the movement of the measuring device 46. Changes in path and pose can be determined. By tracing the direction and distance d of the measurement result obtained by measuring a plurality of measurement points T1 and T2 from the position M1 by the three-dimensional measurement device 46 in the opposite direction from each measurement point, the position M1 of the measurement device 46 and the posture at the time of measurement are obtained. (Orientation of reference direction Z) can be obtained. Similarly, the position M2 of the measuring device 46 and the attitude at the time of measurement can be obtained from the measurement results obtained by measuring the same plurality of measurement points T1 and T2 from the position M2 by the three-dimensional measuring device 46 . This determines the change in position and orientation when the measuring instrument 46 was at M1 and M2. By setting a horizontal plane whose height is equal to M1 or M2 as the reference horizontal plane 11, the relative positional relationship between the three-dimensional shape of the base plane 10 and the reference horizontal plane 11 can be obtained. Marking lines such as crosses may be drawn on the base surface 10 as marks of the measurement points T1 and T2 used for calculation.

Steps S4 to S7 are the same as in the first embodiment.

The present invention is not limited to the above-described embodiments, and various other modifications are possible within the scope of the technical idea of the invention.

10 base surface 11 reference horizontal surface 12 plan finish surface 13 interior reference height 20 marker 20C representative point of marker 21, 22 base 24 transparent container 25 liquid 30 laser marking device 40 three-dimensional measuring instrument 41 projector (projection part)
42 camera (imaging unit)
43 Calculation unit 44 Recording unit 45, 46 Three-dimensional measuring instrument d Distance from the three-dimensional measuring instrument to the measuring point L Height difference between interior reference height and planned finished surface M1, M2 Position of three-dimensional measuring instrument 46 t, t1, t2 Coating thickness of self-leveling material T1, T2 Measuring point θ, φ Direction from three-dimensional measuring device to measuring point Z Reference direction of three-dimensional measuring device 46

Claims (8)

A method for predicting the amount of self-leveling material to be used on a subfloor, comprising:
a marker placement step of placing at least three markers at the same height on or around the base surface so as not to be aligned in a straight line;
a three-dimensional measurement step of acquiring the three-dimensional shape of the base surface and the three-dimensional coordinates of the marker;
setting a planned finished surface parallel to a horizontal surface above the base surface based on the three-dimensional coordinates of the marker;
calculating a predicted usage amount of the self-leveling material based on the three-dimensional shape of the planned finished surface and the base surface;
A method for predicting the amount of self-leveling material used. In the marker placement step, the marker is placed on or around the base surface and then adjusted to the same height using a laser marking machine.
The method for estimating the usage amount of the self-leveling material according to claim 1. The marker is placed in a floating state on the surface of a liquid contained in a transparent container.
The method for predicting the usage amount of the self-leveling material according to claim 1 or 2. The three-dimensional measurement step further acquires the three-dimensional coordinates of the display of the interior reference height that serves as the reference for interior finishing,
The planned finish surface is set as a surface having a predetermined height difference from the interior reference height,
The method for predicting the usage amount of the self-leveling material according to any one of claims 1 to 3. The three-dimensional measurement step uses a portable three-dimensional measuring device to obtain a three-dimensional shape of the entire base surface by combining three-dimensional shapes of each portion of the base surface.
The method for predicting the usage amount of the self-leveling material according to any one of claims 1 to 4. A method for predicting the amount of self-leveling material to be used on a subfloor, comprising:
A three-dimensional measurement step of acquiring the three-dimensional shape of the base surface and setting a reference horizontal plane using a three-dimensional measuring instrument capable of detecting inclination from the horizontal;
setting a planned finish plane above the base plane parallel to the reference horizontal plane;
calculating a predicted usage amount of the self-leveling material based on the three-dimensional shape of the planned finished surface and the base surface;
A method for predicting the amount of self-leveling material used. The three-dimensional measurement step further acquires the three-dimensional coordinates of the display of the interior reference height that serves as the reference for interior finishing,
The planned finish surface is set as a surface having a predetermined height difference from the interior reference height,
The method for estimating the usage amount of the self-leveling material according to claim 6. The three-dimensional measuring instrument is a portable three-dimensional measuring instrument capable of detecting inclination from horizontal,
The three-dimensional measurement step acquires the three-dimensional coordinates of the entire base surface by combining the three-dimensional shape of each portion of the base surface.
The method for predicting the usage amount of the self-leveling material according to claim 6 or 7.

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