DMTY Miniature Earth Pressure Cell

Product Introduction

The DMTY Miniature Earth Pressure Cell is a compact strain-type sensor designed to measure internal stress in soil, sand, mud, and model piles during geotechnical model tests. It can be embedded in or around soil bodies and structural models to monitor pressure distribution and contact stress.

The sensor uses a high-precision full-bridge strain gauge circuit to convert pressure-induced deformation into an electrical signal. Its full-bridge configuration helps compensate for the influence of temperature changes, improving measurement stability during testing.

Available in multiple compact diameters from 12 mm to 80 mm, the DMTY series supports different installation conditions and measurement requirements. Smaller customized sizes, including a diameter of 10 mm, are also available. Side-outlet and bottom-outlet configurations provide flexible cable routing for model test installations.

Suitable for both static and dynamic measurements, the DMTY miniature earth pressure cell can be connected to compatible strain acquisition instruments for geotechnical research and engineering experiments.

Performance Features

•  Miniature dimensions: Available in diameters from 12 mm to 80 mm, with customized sizes as small as 10 mm.

•  Strain-type measurement: Uses a high-precision full-bridge strain gauge to detect pressure-induced deformation.

•   Temperature compensation: The full-bridge circuit helps reduce the influence of temperature changes on measurement results.

•  Customizable measurement range: Standard range of 0.05–10 MPa, with customized ranges available.

•    High measurement accuracy: Specified accuracy of ≤0.5% F.S.

•   Static and dynamic testing: Suitable for measuring steady and changing soil pressure.

•  Flexible cable outlet: Available with side-outlet and bottom-outlet configurations.

• Multiple size options: Different diameters and thicknesses accommodate various model test environments.

•  Data acquisition compatibility: Works with the DMYB series dynamic and static strain acquisition instrument.

• Reusable test sensor: Compact construction supports repeated use in laboratory model testing.

Working Principle

The DMTY miniature earth pressure cell operates using a full-bridge strain measurement principle.

A high-precision full-bridge strain gauge is bonded to the inside of the sensor's sensing membrane. When external pressure acts on the smooth sensing surface, the membrane deforms slightly. This deformation is transferred to the strain gauge, producing a corresponding change in electrical resistance.

The full-bridge circuit converts this resistance change into an electrical signal. A compatible strain acquisition instrument collects and processes the signal to calculate the applied pressure.

The sensor consists of a support plate, sensing plate, observation cable, strain gauge, and related structural components. The smooth surface is the pressure-receiving surface, while the opposite side serves as the support surface.

The full-bridge configuration also helps compensate for temperature-related effects, supporting more stable pressure measurements during model tests.

Technical Parameters

F.S. refers to full scale. Full-scale output is expressed in microstrain (με). The available dimensions and corresponding thicknesses are listed in the order supplied.

Application Scenarios

The DMTY miniature earth pressure cell is designed for geotechnical and structural model testing, including:

•  Soil Mechanics Research: Measuring internal stress distribution in soil samples and soil bodies.

• Sand Model Tests: Monitoring pressure changes within sand masses and granular materials.

•   Mud and Soft Soil Testing: Measuring contact stress in mud and other soft soil media.

•  Model Pile Experiments: Monitoring stress around model piles and pile-soil interaction zones.

•  Foundation Model Testing: Measuring pressure distribution within simulated foundation structures.

•   Geotechnical Engineering Research: Collecting static and dynamic pressure data in laboratory experiments.

•  Underground Structure Models: Monitoring contact pressure in small-scale underground engineering models.

Product Comparison

The DMTY miniature earth pressure cell is designed for small-scale embedded pressure measurement, while larger earth pressure sensors are generally used for broader contact stress measurement.

Selection Guide: Choose the DMTY miniature earth pressure cell for confined installation spaces and small-scale soil or model pile experiments. The larger DMTY earth pressure sensor is more suitable for applications requiring a larger sensing surface and a measurement range up to 20 MPa.

Frequently Asked Questions (FAQ)

1. What is the DMTY miniature earth pressure cell used for?

It measures stress and pressure distribution in soil, sand, mud, and around model piles during geotechnical model tests.

2. What sizes are available?

Standard diameters are 12, 16, 20, 28, 40, 48, and 80 mm, with corresponding thicknesses from 4.2 to 25 mm. Customized sizes as small as 10 mm in diameter are available.

3. What is the measurement range of the DMTY miniature earth pressure cell?

The standard measurement range is 0.05–10 MPa. Customized ranges can be provided according to the test requirements.

4. How does the sensor measure earth pressure?

External pressure deforms the sensing membrane, causing a change in the resistance of the internal full-bridge strain gauge. A compatible strain acquisition instrument processes this signal to calculate the applied pressure.

5. Does the full-bridge circuit provide temperature compensation?

The full-bridge configuration helps reduce the influence of temperature changes on the measurement signal, improving stability during testing.

6. Can the sensor measure both static and dynamic pressure?

Yes. The DMTY miniature earth pressure cell supports both static and dynamic measurements when connected to compatible acquisition equipment.

7. Which cable outlet configurations are available?

Both side-outlet and bottom-outlet configurations are available to accommodate different installation and cable-routing requirements.

8. Which data acquisition instrument is compatible with this sensor?

The sensor can be used with the DMYB series dynamic and static strain acquisition instrument.

9. Can the sensor dimensions and measurement range be customized?

Yes. Both sensor size and measurement range can be customized to suit specific geotechnical model testing requirements.