Orange barrels on a highway


Minnesota's Cold Weather Road Research Facility

Home | Test Cells | Data & Instrumentation | Projects | Reports | About Us | Contact Us

Sensor Data

Pavement or surface layer sensors are installed on, embedded within, or placed immediately under the hot-mix asphalt or concrete layer of a pavement structure. The sensors are linked by fiber optics to MnROAD's computerized data collection system and the data is stored in a database at MnDOT Materials Research and Engineering Laboratory in Maplewood.


There are two categories of pavement sensor:


Traffic load response: Sensors that measure the response resulting from dynamic forces applied by traffic.

Environmental: Sensors that measure the response of slower changing forces like temperature, moisture and frost depth, material expansion/contraction, shrinkage and creep.


All sensors are designated by a two-letter code. Specification and performance history for an individual sensor type is available upon request.



Environmental Effect Sensors

Dynamic Load Sensor

Displacent of Layered Surface

    • DT - Linear Variable Differential Transducer
    • PA - Piezzo-Accelerometer


Displacement [soil]


Pressure in Soil

    • PG - Dynamic Soil Pressure Cell
    • PK - Dynamic Soil Pressure Cell


Dynamic Pore Water Pressure

    • DW - Dynamic Pore Water Pressure Cell


Strain [dowel bar]

    • SS - Steel Strain Gage


Strain [asphalt]

    • AE
    • BS (BL/BT) - Biaxial Strain Gage
    • LE/TE - Bituminous Longitudinal Embedment


Strain [composite/overal]


Strain [concrete]

    • CD - Concrete Embedment Strain Gage
    • CE - Concrete Embedment Strain Gage
    • CS
    • GD - Geokon Dynamic Strain Gage
    • MM - Concrete Embedment Strain Gage


Concrete Maturity:


Crack Detection:



    • FP - Reference Point
    • HC - Horizontal Clip
    • TT/TL - Tiltmeter


Drainage Volume

    • FL
    • TB - Tipping Bucket


Electrical Conductivity [soil]


Elevation Reference

    • IV - Reference Rods


Frost Depth

    • RP - Resistivity Probe


Moisture [concrete]

    • MH - Concrete Moisture
    • MP
    • MR


Moisture [soil]

    • EW
    • HD
    • NP - Access Tube
    • RE
    • TD - Time Domain Reflectometer
    • WM - Moisture Block


Pressure [soil]

    • PL/PT - State Soil Pressure Cell


Environmental Concrete Strain

    • KB/XB - Concrete Strain Transducer
    • VM/XM - Concrete Vibrating Wire Strain Gage [low modulus]
    • VG/XG - Concrete Vibrating Wire Strain Gage [strain gage strength]
    • VW/XV - Concrete Vibrating Wire Strain Gage [low modulus]



    • ET
    • RT
    • TC - Thermocouple
    • TH
    • XB
    • XD - Thermistor in Dynamic Pore Water Pressure Cell
    • XG
    • XH
    • XL - Thermistor in Lateral Pressure Cell
    • XM
    • XS - Thermistor in State Pore Water Presure Cell
    • XT - Thermistor in Soil Pressure
    • XV


Water Table Level

    • OC
    • OS - Open Stand Pipe