CN206479268U - For loess and the forced three-dimensional soil pressure sensor of weak soil - Google Patents

Abstract

The utility model discloses a press-in type three-way earth pressure sensor for loess and soft soil, which comprises a probe shell, the probe shell includes the upper part of the probe shell and the press-in part of the probe shell; the upper part of the side wall of the press-in part of the probe shell It is a cylindrical surface, and the lower part of the side wall is surrounded by three planes with an angle of 60° to each other. There is a circular card slot in the middle of each plane, and a rigid piece is covered and fixed in the circular card slot. The rigid piece The center of the sensor is fixed with a resistance strain gauge attached to it; the resistance strain gauge is connected to the strain acquisition module inside the probe shell through the signal lead wire, and is connected to the host computer signal through the lead wire; the sensor lead wire is fixed horizontally inside the probe shell The electronic compass module connected with the host computer signal. The utility model can realize the measurement of the three-phase earth pressure of loess, soft soil and strata below the groundwater level. Compared with the previous earth pressure measurement scheme, the utility model is easy to install, saves cost and construction period, and has high measurement accuracy.

Description

Press-in three-way earth pressure sensor for loess and soft soil

technical field

The utility model relates to the field of earth pressure detection, in particular to a press-in type three-way earth pressure sensor for loess and soft soil.

Background technique

Earth pressure measurement in rock and soil medium is an important content in soil mechanics theory and geotechnical engineering experimental research. The solution to a large number of geotechnical engineering theory and practical problems often depends on the direct measurement results of on-site models or model tests. At present, soil measurement The basic method is to bury the earth pressure sensor in the soil or on the surface of the structure in the soil, and then directly measure the earth pressure. Because the conditions are easier to achieve than other measurement methods, the earth pressure sensor is still the basic tool for soil medium experimental research in countries all over the world.

In the actual application process, the traditional disc structure earth pressure sensor has the following problems when measuring the pressure of loess and soft soil:

(1) Exploratory well installation is mostly used, which has a long construction period, great difficulty and high cost, especially when it is installed in soft rock and soil or underwater, the construction is difficult and the risk of hole collapse is relatively high;

(2) The installation process requires a large working face, which causes the disturbance of the rock and soil around the sensor, changes the original stress field, and makes the actual pressure measured by the sensor have an error with the real pressure;

(3) A sensor can only measure the earth pressure in one direction; the sensor is placed in a deep place, and the sensor itself cannot detect the position change. In the monitoring of landslides, the position or angle of the sensor changes, which seriously affects the measurement results;

Utility model content

The purpose of the utility model is to overcome the problems existing in the above-mentioned prior art, provide a press-in type three-way earth pressure sensor for loess and soft soil, simplify the measurement of the earth pressure of loess and soft soil, and improve the measurement accuracy.

The technical scheme of the utility model is: a press-in type three-way earth pressure sensor for loess and soft soil, including a probe housing, the probe housing includes a buckle part of the probe housing for connecting the probe rod and a joint with the probe housing. The upper part of the probe housing connected by the buckle part is located below the buckle part of the probe housing; the lower part of the side wall of the upper part of the probe housing is surrounded by three planes at an angle of 60° to each other, and the three planes at an angle of 60° to each other The three intersecting lines between the planes are not parallel at the same time; a circular card slot is opened in the middle of each plane, and a rigid sheet is covered and fixed in the circular card slot, and the center of the rigid sheet is fixed with a The resistance strain gauge on it; the resistance strain gauge is connected with the field bus type acquisition module signal located inside the probe shell through the signal lead wire, and the field bus type acquisition module is connected with the upper computer signal through the sensor lead wire; the probe shell There is also an electronic compass fixed horizontally inside, and the electronic compass is connected with the signal of the upper computer through the electronic compass lead wire.

Preferably, the diameter of the circular card slot is 30 mm; the rigid sheet is a steel sheet with a diameter of 29 mm and a thickness of 1 mm; the steel sheet is fixed in the circular card slot.

Preferably, the side wall of the upper part of the probe housing is a cylindrical surface, and the diameter of the cylindrical surface is 48mm.

Preferably, the middle part of the upper part of the probe housing is provided with through holes for leading out sensor leads and electronic compass leads.

Preferably, after the signal output of the field bus type acquisition module, the signal output of the sensor leads and the output signal of the electronic compass lead, the output signal of the electronic compass lead is directly transferred to the host computer for data analysis and processing after A/D conversion.

Preferably, the connection between the upper part of the probe housing and the buckle part of the probe housing is a buckle connection; the buckle part of the probe housing is threadedly connected to the probe rod.

Preferably, the fieldbus type acquisition module adopts the acquisition module of the model DAQM-4202 produced by Zhouzheng Technology Company.

Beneficial effects of the utility model: In the embodiment of the utility model, a press-in three-way earth pressure sensor for loess and soft soil is provided. Compared with the prior art, the utility model has the following technical advantages:

1. The utility model adopts a self-pressing structure. When testing the earth pressure in loess and soft soil areas, no backfilling is required, and the installation is quick and cost-saving.

2. The utility model adopts a combination of a three-phase pressure sensor and an electronic compass, which can realize precise positioning of the sensor position and more accurate measurement of the pressure.

3. The utility model is suitable for testing the soil pressure of the soil layer below the groundwater level, and solves the problems of difficulty in forming holes and high cost.

4. The measurement data of strain gauges and electronic compass are collected through the field bus type acquisition module, and the direct amplification and transmission reduce signal attenuation, so that the signal is not disturbed and the measurement accuracy is improved.

The sensor of the utility model has the advantages of small volume, low energy consumption, simple structure and greatly reduced cost compared with the prior art.

Description of drawings

Fig. 1 is the overall structure schematic diagram of the utility model sensor;

Fig. 2 is the internal connection schematic diagram of the utility model sensor;

Fig. 3 is a working principle diagram of the loading process using the sensor of the utility model.

Explanation of reference signs:

1. Sensor lead wire; 2. Through hole; 3. The buckle part of the probe shell; 4. The upper part of the probe shell; 5. Fieldbus type acquisition module; 6. Electronic compass; 7. Rigid sheet; 8. Resistance strain gauge; 9. Touching frame; 10. Touching rod.

detailed description

A specific embodiment of the present invention will be described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific embodiment.

The embodiment of the utility model provides a press-in type three-way earth pressure sensor for loess and soft soil, the earth pressure sensor includes a probe shell, and the probe shell includes a probe shell buckle for connecting the probe rod 10 Part 3 and the probe housing upper part 4 connected with the probe housing buckling part 3 and located below the probe housing buckling part 3; , and the three intersecting lines between the three planes with an angle of 60° are not parallel at the same time; that is, the pressed part of the probe shell is a triangular pyramid obtained by cutting the cylinder by three planes with an angle of 60° shape, which is convenient for press-in operation; a circular card slot is opened in the middle of each plane, and a rigid piece 7 is covered and fixed in the circular card slot, and the center of the rigid piece 7 is fixed with a The resistance strain gauge 8; The resistance strain gauge 8 is connected with the field bus type acquisition module 5 signals that are located inside the probe shell through the signal lead wire, and the field bus type acquisition module 5 is connected with the host computer signal through the sensor lead wire 1; The leads of the above-mentioned resistance strain gauges 8 are directly connected to the field bus type acquisition module 5, and the field bus type acquisition module 5 leads four wires of positive power, negative power, A, B. The fieldbus type acquisition module specifically adopts the acquisition module (8-way modulus isolation analog input of RS485 bus line) of the model DAQM-4202 produced by Zhouzheng Technology Company; The electronic compass lead wire is connected with the signal of the host computer, which is convenient for locating the detection position of the three-way earth pressure sensor and improving the measurement accuracy.

As shown in Fig. 1 and Fig. 2, three resistance strain gauges 8 are respectively fixed at the centers of three rigid plates 7, and the three rigid plates 7 are correspondingly fixed on the three upwards (that is, three slopes) of the pressed-in part of the probe shell, and the resistance The lead wires of the strain gauge 8 lead out to the fieldbus type acquisition module 5, and the four lead wires of the fieldbus type acquisition module 5 lead out to the probe; The positive and negative power wires drawn from the compass 6 are connected to the positive and negative power wires of the fieldbus type acquisition module 5 through the 12V-5V step-down module, and connected to the 12V power supply; the final output four sensor lead wires 1 are connected from the through hole 2, which can be connected to to the PC side.

Further, the diameter of the circular card slot is 30 mm; the rigid sheet 7 is a steel sheet with a diameter of 29 mm and a thickness of 1 mm; the steel sheet is fixed in the circular card slot.

Further, the side wall of the probe housing top 4 is a cylindrical surface, and the cylinder diameter of this cylindrical surface is 48mm. The pressing part of the probe (diameter 50mm) is slightly larger than the upper part. When pressing, the whole probe directly contacts the soil layer with small area and small friction, which is convenient for pressing operation. When pressing in, the upper layer of hard soil can be processed by drilling holes. For loess and soft soil, the three-way earth pressure sensor can be assembled and the lead wires can be passed through the pressing pipe. By external pressure, cooperate with the electronic compass 6 to obtain Press the three-way earth pressure sensor to the predetermined position for measurement.

Further, the middle part of the upper part 4 of the probe housing is provided with a through hole 2 for leading out the lead wire 1 of the sensor and the lead wire of the electronic compass.

Further, after the output signal of the sensor lead 1 of the signal output of the fieldbus type acquisition module 5 and the electronic compass lead of the signal output of the electronic compass 6 is converted by A/D, the data is directly transferred to the host computer for data analysis and analysis. deal with. In the data analysis part, the electronic compass 6 can measure the angle between the position of the probe and the Y three-axis as γ, and the three measured data are recorded as F1, F2, and F3. Then, the measured angle in the X-axis direction is earth pressure Earth pressure in the Y-axis direction Earth pressure in the direction of the Z axis

Further, the connection mode between the upper part 4 of the probe housing and the buckle part 3 of the probe housing is a buckle connection; the buckle part 3 of the probe housing is screwed to the probe rod 10 .

A method for measuring a press-in type three-way earth pressure sensor for loess and soft soil, comprising the following steps:

The first step is to level the site first, lay it flat and press it into the host, so that the probe shell is vertically perpendicular to the ground, and place the ground anchor so that it can be fixed and pressed into the host;

In the second step, a plurality of steel pipes that can be connected in sequence are used as the probe rod 10, the power supply cable, the sensor lead wire 1 and the electronic compass lead wire are penetrated into the probe rod 10, and the probe rod 10 is connected with the earth pressure sensor. Connect the circuit and adjust the instrument;

The third step is to drive the earth pressure sensor and the steel pipe as the probe rod 10 into the ground under the action of the pressure machine. During this process, the probe of the earth pressure sensor should be kept vertically pressed into the soil at a uniform speed; The probe frame 9 is supported.

The fourth step is to connect the sensor lead wire 1 and the electronic compass lead wire to the host computer, judge the press-in position and angle according to the feedback signal, adjust to meet the expectation, stop the mechanical action of the pressure, and take out the steel pipe and the buckle part of the probe shell 3.

Fig. 3 is a working principle diagram of the loading process using the sensor of the utility model.

In summary, the embodiment of the utility model provides a press-in three-way earth pressure sensor for loess and soft soil. The earth pressure sensor includes a probe shell, a steel sheet, a resistance strain gauge, an electronic compass, and a field bus Type acquisition module and sensor leads, wherein, the pressed-in part of the probe shell is a cylinder with a diameter of 50mm, which is cut by three planes at 60° to each other, and a circular card slot with a diameter of 30mm is opened in the center of the three planes, with a diameter of 29mm The center of the steel sheet with a thickness of 1mm is pasted with a resistance strain gauge and fixed in the center of the circular card slot; the lead wire of the resistance strain gauge is directly connected to the fieldbus type acquisition module and the data can be directly transmitted to the host computer through the sensor lead wire; the electronic compass is fixed horizontally on the probe Internally, the data is transmitted through the sensor leads; it is convenient to locate the detection position of the three-way earth pressure sensor and improve the measurement accuracy. Many sensor leads drawn from the probe can be converted through the step-down module and converter, and finally output 4 lines, and the leads can directly transmit data to PCs and other equipment for data analysis and processing, which is easy to operate. The diameter of the pressed-in part of the probe shell is 50mm, and the diameter of the other parts is 48mm. The pressed-in part of the probe shell is slightly larger. The earth pressure sensor of the utility model is a press-in type earth pressure sensor, which is suitable for various earth pressure measurements, especially the earth pressure measurement of loess and soft soil where the sensor is not suitable to be drilled into the sensor. The probe can be directly inserted into the soil for measurement. Pressure measurement, compared with other current soft soil pressure measurement methods, is simpler, easier to operate and cheaper. The earth pressure sensor of the utility model can measure the earth pressure in three directions, and calculate the earth pressure of the position through the position sensor and the direction measurement module, avoiding the earth pressure sensor tilting or failing to reach due to other installation methods The earth pressure measurement error caused by the predetermined position, compared with the single-phase sensor, has higher accuracy.

Compared with the prior art, the utility model has the following technical advantages:

1. The utility model adopts a self-pressing structure. When testing the earth pressure in loess and soft soil areas, no backfilling is required, and the installation is quick and cost-saving.

2. The utility model adopts a combination of a three-phase pressure sensor and an electronic compass, which can realize precise positioning of the sensor position and more accurate measurement of the pressure.

3. The utility model is suitable for testing the soil pressure of the soil layer below the groundwater level, and solves the problems of difficulty in forming holes and high cost.

4. The measurement data of strain gauges and electronic compass are collected through the field bus type acquisition module, and the direct amplification and transmission reduce signal attenuation, so that the signal is not disturbed and the measurement accuracy is improved.

The sensor of the utility model has the advantages of small volume, low energy consumption, simple structure and greatly reduced cost compared with the prior art.

The above disclosures are only a few specific embodiments of the present invention, but the embodiments of the present invention are not limited thereto, and any changes conceivable by those skilled in the art should fall within the scope of protection of the present invention.

Claims (7)

1. for loess and the forced three-dimensional soil pressure sensor of weak soil, including probing shell, it is characterised in that the probe Shell includes the probing shell buckle part (3) for connecting sounding rod (10) and connected with the probing shell buckle part (3) The probing shell top (4) being located at below probing shell buckle part (3) connect；The side wall of the probing shell top (4) Bottom is surrounded by the plane of three 60 ° of angles each other, and three three intersecting lenses each other between the plane of 60 ° of angles it is different when It is parallel；It is provided with the medium position of each plane and rigid disk (7), institute is covered and be fixed with circular neck, the circular neck The center for stating rigid disk (7) is fixed with resistance strain gage (8) attached to it；The resistance strain gage (8) is drawn by signal Line is connected with on-site bus type acquisition module (5) signal inside probing shell, the on-site bus type acquisition module (5) It is connected by sensor lead (1) with host computer signal；Electronic compass (6) is also horizontally fixed with inside the probing shell, electricity Sub- compass (6) is connected by electronic compass lead with host computer signal.

2. as claimed in claim 1 for loess and the forced three-dimensional soil pressure sensor of weak soil, it is characterised in that described A diameter of 30mm of circular neck；The rigid disk (7) be steel disc, a diameter of 29mm of steel disc, thickness is 1mm；The steel disc It is fixed in the circular neck.

3. as claimed in claim 1 for loess and the forced three-dimensional soil pressure sensor of weak soil, it is characterised in that described The side wall on probing shell top (4) is the face of cylinder, and the body diameter on the face of cylinder is 48mm.

4. as claimed in claim 1 for loess and the forced three-dimensional soil pressure sensor of weak soil, it is characterised in that described The through hole (2) for drawing sensor lead (1) and electronic compass lead is provided with the middle part of probing shell top (4).

5. as claimed in claim 1 for loess and the forced three-dimensional soil pressure sensor of weak soil, it is characterised in that described Sensor lead (1), electronics sieve of the signal output of electronic compass (6) of the signal output of on-site bus type acquisition module (5) After the output signal of disk lead is changed by A/D, the incoming host computer of data is directly subjected to data analysis and process.

6. as claimed in claim 1 for loess and the forced three-dimensional soil pressure sensor of weak soil, it is characterised in that described Connected mode between probing shell top (4) and probing shell buckle part (3) is to snap connection；Probing shell buckle part (3) it is threadedly coupled with sounding rod (10).

7. as claimed in claim 1 for loess and the forced three-dimensional soil pressure sensor of weak soil, it is characterised in that described The acquisition module for the model DAQM-4202 that on-site bus type acquisition module (5) is produced using Zhou Zheng scientific ＆ technical corporation.