JP7437702B2 - wall soil pressure gauge - Google Patents

Description

The present invention relates to a wall earth pressure gauge that is installed on a wall to detect earth pressure, and particularly to a wall earth pressure gauge that can simultaneously detect vertical earth pressure and horizontal shear force.

The wall soil pressure gauge described in Patent Document 1 was developed by the applicant.
This sensor has a parallel shear beam as a detection beam and a bent beam orthogonal to the parallel shear beam in the sensitive part of the soil pressure gauge, and detects the friction force in the direction orthogonal to the friction force detected by the parallel shear beam. It is.
In the wall soil pressure meter described in Patent Document 1, the detection beams are arranged in a cross shape, and the pressure receiving plate fixing part and the bearing plate fixing part are arranged independently at the ends of the detection beams symmetrically about the x-axis and the y-axis, respectively. (Refer to Cited Document 1: Figure 6).
Furthermore, a configuration is also described in which a ring-shaped disk is provided on the outer periphery, and a pressure receiving plate fixing portion and a pressure bearing plate fixing portion are provided above and below the disk (refer to Cited Document 1: FIG. 7).

Utility model registration No. 3208784

The surface of the pressure receiving plate and the pressure bearing plate fixing portion have a certain distance. Therefore, when a load is applied to the pressure plate, a rotational moment acts on the detection beam, which causes shearing force to act on each fixed part, and the rotational moment and shearing force interfere with the detection of wall earth pressure and frictional force. This happened (Figure 7).
Further, when a ring-shaped disk is provided on the outer periphery, the width of the ring portion in the radial direction is thicker than the plate thickness of the detection beam, which may impede detection by the detection beam.

An object of the present invention is to provide a wall soil pressure gauge with higher accuracy.

The present invention, which has been made to achieve the above object, includes a pressure receiving plate disposed on a wall that receives earth pressure, a sensitive part that detects the earth pressure acting on the pressure receiving plate, and a sensitive part that detects the earth pressure acting on the pressure receiving plate through the sensitive part. The sensitive part has a supporting pressure plate that supports the sensing beam connecting part provided at the center, and the sensing beam connecting part is viewed from above, and the center is the intersection of the x-axis and the y-axis. a plate-shaped detection beam extending in a cross shape parallel to the axis; a pressure plate fixing part provided at an end of the detection beam parallel to the x-axis and fixed to the pressure plate ; and the detection beam parallel to the y-axis. and a plate-shaped outer peripheral beam that connects the pressure receiving plate fixing part and the pressure plate fixing part at the outer periphery, and the pressure plate fixing part is provided at the end of the plate and is fixed to the pressure plate, and the plate-shaped outer peripheral beam connects the pressure plate fixing part and the pressure plate fixing part at the outer periphery. To provide a wall soil pressure gauge that can simultaneously detect the shear force of
A plate thickness of the outer peripheral beam in a plane direction defined by the x-axis and the y-axis may be thinner than a plate thickness of the detection beam in a plane direction defined by the x-axis and the y-axis.
The outer peripheral beam may have a circular shape in plan view.
The outer peripheral beam may have a rectangular shape in plan view.
The outer peripheral beam may linearly connect the pressure receiving plate fixing part and the bearing pressure plate fixing part.

The present invention can obtain at least one of the following effects by means for solving the above problems.
(1) The outer peripheral beam acts as a reinforcing material, resists various external forces, and suppresses excessive deformation of the detection beam due to external forces.
(2) By making the outer peripheral beam thinner than the detection beam, the outer peripheral beam does not interfere with strain detection by the detection beam.

An explanatory diagram of the wall soil pressure gauge of the present invention An explanatory diagram of the sensitivity section of the wall soil pressure meter of the present invention Explanatory diagram of bridge circuit Explanatory diagram of the sensitive part when subjected to load (1) Explanatory diagram of the sensitive part when subjected to load (2) An explanatory diagram of the sensitivity section of the wall soil pressure meter of the present invention according to other embodiments Illustration of a conventional wall soil pressure gauge

Hereinafter, the wall soil pressure gauge of the present invention will be explained in detail with reference to the drawings.

[Example 1]
(1) Wall Earth Pressure Gauge The wall earth pressure gauge of the present invention is installed on a wall to detect earth pressure acting on the wall.
The wall soil pressure gauge of the present invention includes a pressure receiving plate 1 disposed on a wall that receives earth pressure, a sensitive part 2 that detects the earth pressure acting on the pressure receiving plate 1, and a bearing plate 3 that supports the pressure receiving plate 1 and the sensitive part 2. It consists of (Figure 1).
The bearing plate 3 is fixed within the wall.
The pressure-bearing plate 3 has an airtight peripheral wall 31 formed around it, and an airtight material such as an O-ring is disposed between it and the pressure-receiving plate 1 .
A strain gauge 4 is attached to the detection beam 23 of the sensitive section 2, and the strain gauge 4 detects shear strain and bending strain of the sensitive section 2, and measures earth pressure.

(2) Sensitivity part The sensitivity part 2 has a detection beam connection part 24 of a substantially square shape, a center of the detection beam connection part 24 as the intersection of the x-axis and the y-axis, and a pressure-receiving plate fixing part 21 symmetrically with respect to the x-axis. The fixed part 22 is divided into two parts symmetrically about the y-axis, and two parallel plate-shaped detection beams 23 are arranged symmetrically about the x-axis and the y-axis (FIG. 2).
The pressure receiving plate fixing portion 21 is fixed to the pressure receiving plate 1. Further, the bearing pressure plate fixing portion 22 is fixed to the bearing pressure plate 3.
The outer peripheries of the pressure receiving plate fixing part 21 and the bearing pressure plate fixing part 22 are integrally formed by a plate-shaped outer circumferential beam 25 having a circular shape in plan view.
The detection beam 23 and the outer peripheral beam 25 are arranged with the height direction of the sensitive part 2 (the direction of the pressure receiving plate 1 to the pressure plate 3 of the wall soil pressure gauge) as the plate width direction. The thickness of the outer peripheral beam 25 in the plane direction defined by the x-axis and the y-axis is made thinner than the plate thickness of the detection beam 23 in the plane direction defined by the x-axis and the y-axis.

(3) Measuring frictional force and earth pressure Frictional force in the X direction can be measured at four locations inside x1 to x4 of the detection beam 23, and frictional force in the Y direction can be measured at four locations inside y1 to y4 of the detection beam 23. Earth pressure (Z-direction vertical force) is measured using strain gauges 4 attached to four locations inside 23 of the detection beams z1 to z4 (one of each).
These strain gauges 4 are connected to the bridge circuits shown in FIGS. 3(a), (b), and (c), respectively, and include a bridge circuit 51 for measuring frictional force in the X direction, a bridge circuit 52 for measuring frictional force in the Y direction, A bridge circuit 53 for earth pressure measurement is configured, and input lines and output lines of each bridge circuit 51, 52, and 53 are connected to the measurement cable 6 and led out to the outside.

(4) Effect of outer peripheral beam The pressure receiving plate fixing part 21 and the bearing pressure plate fixing part 22 are integrally formed by the outer peripheral beam 25 which has a circular shape in plan view.
Therefore, the outer peripheral beam 25 serves as a reinforcing member, resists various external forces, and suppresses excessive deformation of the detection beam 23 due to external force. At this time, since the outer peripheral beam 25 is thinner than the detection beam 23, it does not interfere with the detection of strain by the detection beam 23.

That is, when a lateral load acts on the pressure receiving plate 1, if the outer peripheral beam 25 is not present, only the detection beam 23 (in the X-axis direction in FIG. Although the rotational movement of the pressure receiving plate 1 cannot be suppressed, the load is also distributed to the pressure plate fixing part 22 by the outer peripheral beam 25, the rotational movement of the pressure receiving plate 1 in the lateral load direction is suppressed, and highly accurate measurement can be performed (Fig. 4 ).

In addition, when a vertical load is applied to the pressure receiving plate 1, the rotational moment acting on the detection beam 23 is suppressed by the outer peripheral beam 25, suppressing the generation of shear force in each fixed part 21 and 22, and ensuring highly accurate measurement. (Figure 5).

[Other Examples]
In the above embodiment, the outer peripheral beam 25 has a circular shape in plan view, but may connect the pressure receiving plate fixing part 21 and the bearing plate fixing part 22 in a straight line (FIG. 6(a)), or may have a rectangular shape in plan view. It may be configured to do so (FIG. 6(b)).
Moreover, although the detection beam 23 is a parallel beam, it may be constructed of a single flat plate.

1 Pressure receiving plate 2 Sensitive part 21 Pressure receiving plate fixing part 22 Bearing pressure plate fixing part 23 Detection beam 24 Detection beam connecting part 25 Peripheral beam 3 Bearing plate 31 Airtight peripheral wall part 4 Strain gauge 51 Bridge circuit for measuring X-direction friction force 52 Y-direction friction Bridge circuit for force measurement 53 Bridge circuit for earth pressure measurement 6 Measurement cable

Claims (5)

A pressure receiving plate placed on a wall that receives earth pressure;
a sensitive section that detects earth pressure acting on the pressure receiving plate;
a bearing plate that supports the pressure receiving plate via the sensitive part,
The sensitive section includes a detection beam connecting section provided at the center;
A plate-shaped detection beam that extends in a cross shape parallel to the x-axis and the y-axis with the center thereof as the intersection of the x-axis and the y-axis when the detection beam connection portion is viewed from above;
a pressure plate fixing part provided at an end of the detection beam parallel to the x-axis and fixed to the pressure plate ;
a bearing plate fixing part provided at an end of the detection beam parallel to the y-axis and fixed to the bearing plate ;
a plate-shaped outer peripheral beam connecting the pressure receiving plate fixing part and the bearing pressure plate fixing part at the outer periphery;
A wall soil pressure meter that can simultaneously detect vertical soil pressure and horizontal shear force. A thickness of the outer peripheral beam in a plane direction defined by the x-axis and the y-axis is thinner than a plate thickness of the detection beam in the plane direction defined by the x-axis and the y-axis. , The wall soil pressure gauge according to claim 1. The wall soil pressure gauge according to claim 1 or 2, wherein the outer peripheral beam has a circular shape in plan view. The wall soil pressure gauge according to claim 1 or 2, wherein the outer peripheral beam has a rectangular shape in plan view. The wall earth pressure gauge according to claim 1 or 2, wherein the outer peripheral beam connects the pressure receiving plate fixing part and the bearing pressure plate fixing part on a straight line.

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