JPS63138243A - Automatic measuring system for clamping degree of bulk substance by electromagnetic wave - Google Patents

Abstract

PURPOSE:To satisfactorily execute a clamping work by moving a measuring instrument provided with an electromagnetic wave emitter and a receiver, emitting an electromagnetic wave into a bulk substance, receiving a reflected wave from a boundary surface to a substrate, and measuring the variation of electric characteristics caused by ground clamping of the bulk substance. CONSTITUTION:By a movable measuring instrument which is provided with an electromagnetic wave transmitter 6 and a receiver 7, a measurement for the clamping degree of the bulk substance is executed. An electromagnetic wave W from this transmitter 6 is emitted to soil 2 from a transmitting antenna 4, and a reflected wave from the boundary to the substrate 1 is received by a receiving antenna 5 and led to the receiver 7. A signal received by this receiver 7 is sent to an analyzer 8, in which electric characteristics (for instance, the velocity of propagation, dielectric constant, attenuation factor, etc.) of the soil 2 by the electromagnetic wave W are calculated. From these electric characteristics, the clamping state of the soil 2 is detected, and displayed on an indicator 9. Accordingly, by measuring continuously and automatically the variation of the characteristic value, a soil structure which is clamped uniformly can be constructed.

Description

[Detailed Description of the Invention] [Fields of Application in Industry] The present invention uses electromagnetic waves to measure the degree of compaction of loose materials such as roadbed materials, lma materials, asphalt paving materials, and crushed stone materials. The present invention relates to a system for automatically measuring using

[Prior Art and Its Problems] Generally, compaction is carried out to reduce voids in embankments, prevent harmful subsidence, increase the bearing capacity of embankments, and stabilize the sloping surface.

Conventionally, to compact an embankment, each layer is spread in a thin uniform layer and compacted a predetermined number of times to obtain the required degree of compaction, using a compaction method suitable for the selected embankment material. That's what I do.

By the way, compaction cannot be determined just by looking at it, so
Strict control must be exercised during construction, and it must be checked whether the required degree of compaction is achieved.

Conventional compaction tests include the sand displacement method, the RTR (radioisotope) method, and the CBR (cal iro
The r++ia bearing ratio) method is mainly adopted.

The sand replacement method is a method in which the volume of a hole drilled in the ground is replaced with sand, and the volume of the soil is indirectly measured to measure the density of the ground. However, this method not only takes a long time to measure, making it impossible to measure a large number of measurement points, but also has problems such as destroying the finished ground surface.

The RI method is a measurement method that utilizes the principle that the rate at which gamma rays are absorbed into soil particles when they pass through the soil has a constant relationship with the density of the soil. however,
Radiation such as gamma rays has problems such as radiation damage,
Not only was radiation management difficult, but there were also problems such as measurement being time consuming.

Furthermore, in the above CBR method, a penetrating rod with a diameter of 5 cI11 is
．． This method measures the degree of soil compaction by dividing the load when penetrating 25 cm by 1.370 kg and expressing it as a percentage. However, this method also has problems in that it requires extensive preparation and is easily influenced by the strength of the surface.

In any of the above methods, measurement is discontinuous, so not only cannot the whole be measured evenly and in real time, but also cannot be accurately grasped.

Therefore, there are problems in that it cannot be used for compaction construction management that produces an even and homogeneous finish.

1.0 points of the invention 1. The present invention was made in order to solve the above-mentioned conventional problems, and its zero point is that the same point can be repeatedly measured without contact or non-destructively. The compaction of loose materials using electromagnetic waves allows for extremely short measurement times and enables real-time measurements, allows measurements to be taken at multiple locations in a short time, and enables the construction of high-quality, uniformly compacted earth structures. The purpose of the present invention is to provide an automatic degree measurement system.

[Structure 1 of the Invention The system for automatically measuring the degree of compaction of loose materials using electromagnetic waves according to the present invention moves a measuring device comprising electromagnetic wave emitting means, electromagnetic wave receiving means, etc. over loose materials that have been spread and compacted on a base. While emitting electromagnetic waves into the loose material, reflecting them at the interface with the substrate, and receiving the reflected electromagnetic waves,
This device is characterized by continuously measuring changes in electrical properties due to compaction of bulk materials, and is also characterized by displaying or recording the distribution of the degree of compaction based on the measured values. be.

In addition, the above-mentioned foundation must be a layer such as a lower embankment, a concrete layer, an asphalt layer, etc., and must have a clear interface with the compacted layer above it and a surface that can reflect electromagnetic waves. No.

In addition, the above-mentioned bulk materials include embankment materials, roadbed materials, roadbed materials, AS7A M covering materials, crushed stone materials, and the like.

Further, as a means for moving the measuring device, it is mounted on a trolley, a self-propelled compaction rock, or the like.

[Embodiment 1] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In the figure, reference numeral 1 denotes a base, on which soil 2 as a material to be compacted is leveled and compacted by rolling with rollers or the like.

A cart 3 is adapted to move on the surface of the soil 2. A transmitting antenna 4 and a receiving antenna 5 are placed on the trolley 3 at predetermined intervals.

The transmitting antenna t transmits an electromagnetic wave W generated by the transmitter 6.
Fire into the soil 2 above.

The electromagnetic wave W emitted from the transmitting antenna 4 passes diagonally downward through the soil 2, is reflected at the boundary between the base 1 and the soil 2, and travels toward the diagonally upper blade, and then passes through the soil 2 to the receiving antenna 5. received by. Emitted from the transmitting antenna 4,
The electromagnetic waves ~V transmitted through the soil 2 before being received by the receiving antenna 5 have their speed reduced or energy deposited due to particles and moisture in the soil 2 along the way.

The reflected electromagnetic wave W received by the multi-layer receiving antenna 5 is sent to the receiver 7.

Further, the transmitter 6 and the receiver 7 are sequentially connected to an analyzer 8, a display 5), and the like.

Next, measurement operations using the apparatus of the embodiment described in -I- will be explained.

First, a table 1113 with a measuring device mounted on the compacted soil 2
While running, an electromagnetic wave W with a frequency that is most strongly affected by compaction is transmitted from the transmitter 3 6, and the electromagnetic wave ~■ reflected from the boundary between the foundations 1 and -12 is received by the receiver 44 antenna 5. It is sent to receiver 7.

The signal of the received electromagnetic wave W is sent to the analyzer 8, where the electrical characteristics of the soil 2 due to the electromagnetic wave W (for example, propagation velocity ν, relative dielectric constant ε, mounting ratio, etc.) are calculated. These electrical properties (velocity of propagation ν, relative dielectric constant ε, attenuation rate, etc.) are
The degree of compaction of the soil 2 can be determined by reading such electrical characteristics.

The electrical characteristics measured and analyzed as described above are displayed on the display 9.
In addition to displaying graphs in real time and allowing immediate visual inspection, the measurement results can be stored (recorded, memorized, etc.) as a distribution of the degree of compaction in the entire measurement area, and can be compared relatively. ing.

Therefore, the compaction manager must set a certain value (preset W management standard) based on the record of the distribution of the degree of compaction.
The compaction work is repeated while checking with the measuring device mentioned above until the compaction is reached.

Note that the measuring devices such as the transmitting antenna 4 and the receiving antenna 5 are moved by a compaction device such as a road roller instead of being moved by the trolley 3. It may also be moved by ramming.

[Effects of the Invention 1 (1) The system of the present invention emits electromagnetic waves into the bulk material while moving a measuring device consisting of an electromagnetic wave emitting means, an electromagnetic wave receiving means, etc. on the bulk material that has been spread and compacted on a base. The electromagnetic waves are reflected at the interface with the base, and the reflected electromagnetic waves are received to continuously measure the changes in electrical properties due to the compaction of loose materials.・Since it can be measured non-destructively and the measurement time is extremely short, it is possible to measure not only in many places but also continuously, and to construct high-quality and uniformly compacted earth structures. It becomes possible.

(2) Since the distribution of the degree of compaction is displayed or recorded based on the measured values, it becomes extremely easy to manage the overall degree of compaction.

[Brief explanation of the drawing]

The figure is a conceptual diagram of an apparatus implementing the measurement system of the present invention. 1... Base, 2... Soil, 3... Trolley, 4... Transmitting antenna, 5... Receiving antenna, 6... Transmitter,
7...Receiver, 8...Analyzer, 9...Display device, W
...Electromagnetic waves.

Claims (2)

[Claims] (1) Electromagnetic waves are emitted into the bulk material while moving a measuring device consisting of an electromagnetic wave emitting means, an electromagnetic wave receiving means, etc. over the bulk material that has been spread and compacted on the substrate, and 1. An automatic measuring system for measuring the degree of compaction of loose materials using electromagnetic waves, characterized by reflecting electromagnetic waves, receiving the reflected electromagnetic waves, and continuously measuring changes in electrical properties due to compaction of loose materials. (2) The first aspect of claim 1 is characterized in that the distribution of the degree of compaction is displayed or recorded based on the measured values.
An automatic measuring system for the degree of compaction of bulk materials using electromagnetic waves as described in 2.