JPH06249724A - Geostatic gauge - Google Patents

Abstract

PURPOSE:To allow highly reliable geostatic measurement of curved surface or sandy ground by arranging a plurality of load gauges oppositely to the plane of a pressure receiving beam touching a part to be measured. CONSTITUTION:Since the pressure receiving beam 4 of a geostatic gauge 1 is a long rigid body, geostatic pressure is received accurately by the pressure receiving beam 4 regardless of the properties of the ground, e.g. the grain size of soil. Furthermore, since the pressure receiving plane 4a is curved, geostatic pressure of curved surface is received accurately. Since a long pressure receiving beam 4 and two load gauges 3 are used, any one part of the pressure receiving beam 4 is subjected to maximum geostatic pressure even if the geostatic pressure is different at respective parts within a ground to be measured, and an average geostatic pressure acting on the pressure receiving plane can be measured. Furthermore, since the geostatic pressure is measured while holding the pressure receiving beam 4 and the load gauge 3 in a groove 5 of a rod 2, measuring work is facilitated while suppressing measurement error.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth pressure gauge used for a ground behavior test or the like during an earthquake, for example.

[0002]

2. Description of the Related Art Generally, when building a large-scale building such as a high-rise building, it is necessary to confirm the properties of the ground by experiments in order to know the properties of the ground on which the building is constructed during an earthquake. ing. As such a ground property test, for example, a method is known in which a centrifugal force is applied to a model containing the experimental ground and a load is applied to the ground by the centrifugal force to measure the earth pressure. As a load meter used when performing such an experiment, an earth pressure gauge in which the earth pressure directly acts on a sensor portion for measuring the earth pressure is often used. In the conventional art, for example, an earth pressure gauge as shown in FIG. 4 is used. Are known. The earth pressure gauge shown in FIG. 4 is a diaphragm type load meter in which a diaphragm is provided on a ring, and this diaphragm type load meter measures the earth pressure based on the displacement of the diaphragm by directly acting the earth pressure on the diaphragm. .

[0003]

When the earth pressure is measured by a conventional earth pressure gauge, the ordinary measurement is possible when the soil particles in the measurement ground are fine, but when the soil particles are coarse, Since the pressure receiving surface is small, there is an inconvenience that an error occurs in the measured value. Further, since the displacement of the diaphragm is measured at one measurement point, the reliability of the measured earth pressure is low, and the stress is concentrated on the diaphragm ring due to the earth pressure, so that the measurement by the diaphragm becomes inaccurate. .
In addition, since the pressure receiving surface of the diaphragm is flat, there is a problem that curved surface earth pressure cannot be measured. Is not added, there is a problem that measurement cannot be actually performed. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an earth pressure gauge that can perform measurement on a curved surface earth pressure and sand ground and has a small measurement error and high reliability. To do.

[0004]

An earth pressure gauge according to claim 1 for solving the above-mentioned problems is an elongated pressure-bearing beam which comes into contact with a measured portion of the ground to receive the earth pressure of the measured portion. And a plurality of load cells arranged on the surface opposite to the surface of the pressure receiving beam that contacts the portion to be measured so as to contact the pressure receiving beam at a certain distance in the longitudinal direction of the pressure receiving beam. . The earth pressure gauge according to claim 2 is the earth pressure gauge according to claim 1, wherein the earth pressure gauge includes a rod having a groove in a longitudinal direction and a load meter mounting hole at a bottom surface of the groove, and the rod is provided in the load meter mounting hole. The load meter is arranged, and the pressure receiving beam is arranged in the groove. An earth pressure gauge according to a third aspect of the present invention is the earth pressure gauge according to the first aspect or the second aspect, wherein a surface of the pressure receiving beam that abuts against the measured portion is a curved surface.

[0005]

The earth pressure gauge according to claim 1 comprises a long pressure receiving beam for receiving the earth pressure, and a plurality of load gauges arranged on the surface opposite to the surface of the pressure receiving beam which abuts against the measured portion. It has. Therefore, the earth pressure of the ground acts on the long pressure receiving beam, and the displacement of the pressure receiving beam caused by this is detected by the load meter as the earth pressure. The earth pressure gauge according to claim 2 is provided with a rod having a groove in the length direction and a load meter mounting hole on the bottom surface of the groove, the load meter is arranged in the load meter mounting hole, and the pressure receiving beam is arranged in the groove. ing. Therefore, since the pressure receiving beam and the load meter are housed in the groove of the rod, it is possible to perform the measurement with the pressure receiving beam and the load meter held in the fixed positions. In the earth pressure gauge according to claim 3, since the surface of the pressure receiving beam that abuts against the measured portion is a curved surface,
If the pressure receiving surface is formed by matching the curvature of the curved surface of the pressure receiving beam with the curvature of the curved surface of the ground, the curved surface earth pressure can be accurately transmitted to the pressure receiving beam for measurement.

[0006]

EXAMPLES Examples according to the present invention will be described below. FIG. 1 shows an embodiment of the earth pressure gauge of the present invention, and FIG. 2 shows the earth pressure measurement in a centrifugal model experiment using this earth pressure gauge. In FIG. 1, reference numeral 1 indicates an earth pressure gauge, and the earth pressure gauge 1 includes a rod 2, load meters 3 and 3 attached to the rod 2, and pressure receiving beams arranged on the load meters 3 and 3. 4 and 4. Rod 2
Is an aluminum rod with a circular cross section,
Grooves 5 are formed in the length direction. On the bottom surface of the groove 5, a narrow groove 6 having a smaller width dimension cut further downward than the groove 5 is formed, and load meter arrangement holes 7, 7 are formed at regular intervals in the length direction. ing. The load cells 3 and 3 are inserted and arranged in the load cell placement holes 7 and 7, and the lead wires 8 and 8 for taking out the output of the load cells 3 and 3 are pulled out to the outside of the rod 2 through the narrow groove 6, Line 8,
Reference numeral 8 is connected to a control unit (not shown).

A pressure receiving beam 4 is arranged in the groove 5 of the rod 2, and the pressure receiving beam 4 is formed of a long aluminum rod having a substantially rectangular cross section. The pressure receiving surface 4a of the pressure receiving beam 4 is provided with the groove 5
The pressure receiving surface 4a is a curved surface curved in the direction along the outer peripheral surface 2a of the rod 2.

Next, a procedure for measuring earth pressure in a centrifugal model test using the earth pressure gauge 1 will be described.
In FIG. 2, reference numeral 9 is the ground, reference numeral 10 is a structure buried in the ground, and the earth pressure gauge 1 is arranged in the structure 10. In this case, the pressure receiving surface 4a of the pressure receiving beam 4 of the earth pressure gauge 1
Are arranged so as to be in contact with the ground 9a along the structure 10. In this state, when a centrifugal force is applied to the ground 9 to change the earth pressure, the earth pressure acts on the pressure receiving surface 4a of the pressure receiving beam 4, and this displacement is transmitted to the load cells 3 and 3. The outputs of the load cells 3 and 3 are sent to the control unit through the lead wires 8 and 8 to measure the earth pressure.

FIG. 3 shows the measurement results of the earth pressure actually measured in the centrifugal model experiment using the earth pressure gauge 1. The horizontal axis shows the acceleration given to the ground, and the vertical axis shows the earth pressure measured at the acceleration in units of 5 ksc (5 kg / cm ² ). As a comparative experiment, the results of actual measurement of earth pressure with a conventional diaphragm-type earth pressure gauge were shown in the same manner as the theoretical earth pressure. As shown in FIG. 3, it is understood that the pressure-bearing beam type earth pressure gauge of the present invention has a considerably smaller error from the theoretical earth pressure than the diaphragm type earth pressure gauge.

When the earth pressure is measured by the earth pressure gauge 1 described above, since the pressure receiving beam 4 is long and is a rigid body, the earth pressure is not applied to the pressure receiving beam 4 regardless of the characteristics of the ground such as the size of soil particles. Since the pressure is accurately received and the pressure receiving surface 4a is formed on the curved surface, the curved surface earth pressure can be accurately received. Also, the pressure receiving beam 4
Is long and has two load cells 3 and 3, even if there is a difference in the earth pressure of each part in the ground that is the part to be measured, any part of the pressure receiving beam 4 will produce the maximum earth pressure. The average earth pressure acting on the pressure receiving surface can be measured. Further, since the pressure receiving beam 4 and the load cells 3 and 3 can be held in the groove 5 of the rod 2 to measure the earth pressure, the measurement work is easy.

Although the pressure receiving surface 4a of the pressure receiving beam 4 is a curved surface, the curvature of the pressure receiving surface 4a is formed according to the curvature of the ground to be measured, and when the measured portion of the ground is a flat surface,
The pressure receiving surface 4a of the pressure receiving beam 4 is a flat surface.

[0012]

According to the earth pressure gauge of the first aspect of the present invention, the long pressure receiving beam for receiving the earth pressure and the plurality of load cells arranged on the surface opposite to the surface of the pressure receiving beam that abuts against the measured portion. It has and. Therefore, since the pressure receiving beam for receiving the earth pressure of the ground is a rigid body and has a large pressure receiving surface, the earth pressure can be measured regardless of the nature of the ground and an error does not easily occur in the measured value. In addition, the pressure beam is long and there are multiple load cells,
Therefore, the displacement due to earth pressure can be measured at multiple measurement points, so the reliability of the measured earth pressure is high. The earth pressure gauge according to claim 2 is the earth pressure gauge according to claim 1, further comprising a rod having a groove in a length direction and a load meter mounting hole at a bottom surface of the groove, and the load meter is disposed in the load meter mounting hole. A pressure beam is arranged in the groove. Therefore, the pressure-bearing beam and the load meter can be held in a fixed position for measurement, and thus the measurement work is easy and an error in the measured value hardly occurs. An earth pressure gauge according to a third aspect of the present invention is the earth pressure gauge according to the first aspect or the second aspect, wherein a surface of the pressure receiving beam that abuts against the measured portion is a curved surface. Therefore, even if the measured portion of the ground is a curved surface, the curved surface earth pressure can be accurately measured.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an earth pressure gauge of the present invention.

FIG. 2 is a cross-sectional view showing a state in which earth pressure is measured by the earth pressure gauge.

FIG. 3 is a graph showing measured earth pressure and theoretical earth pressure measured by the earth pressure gauge and the diaphragm-type earth pressure gauge.

FIG. 4 is a perspective view showing a state of measuring earth pressure with a conventional earth pressure gauge.

[Explanation of symbols]

 1 Earth pressure meter 2 Rod 3 Load meter 4 Pressure receiving beam 4a Pressure receiving surface 5 Groove 7 Load meter placement hole 9 Ground

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Tatsuya Moro 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Yoshihisa Yamazaki 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd.

Claims (3)

[Claims] 1. A long pressure-bearing beam that abuts against a measured portion of the ground to receive the earth pressure of the measured portion, and a surface of the pressure-receiving beam opposite to a surface that abuts against the measured portion. An earth pressure gauge, comprising: a plurality of load cells arranged so as to come into contact with each other in the longitudinal direction of the pressure receiving beam with a certain distance therebetween. 2. The earth pressure gauge according to claim 1, further comprising a rod having a groove in a length direction and a load meter mounting hole provided on a bottom surface of the groove, wherein the load meter is provided in the load meter mounting hole. An earth pressure gauge, wherein the earth pressure gauge is arranged, and the pressure receiving beam is arranged in the groove. 3. The earth pressure gauge according to claim 1 or 2, wherein a surface of the pressure receiving beam that abuts against the measured portion is a curved surface.