SURROGATE BRIDGE FREEZING SENSORS

1,18

MB

137

stron

5035

ID

Oklahoma State University

2000

rok

TABLE OF CONTENTS

I. INTRODUCTION 1

1.1. Background 1

1.2. Literature Survey 4

1.2.1. Aircraft Ice Sensors 5

1.2.1.1. Pruzan (1993) 5

1.2.1.2. Feely (1994) 7

1.2.1.3. Ringer and Stallabrass (1993) . 8

1.2.2. Pavement and Road Surface Ice Detection Sensors. 8

1.2.2.1. Finkele (1997) . 8

1.2.2.2. Ciamberlini, at al. (1994) 9

1.2.2.3. Besant, at al. (1994). 12

1.2.2.4. Ciemochowski (1969) . 12

1.2.2.5. Mawhinney and McCone (1974) 15

1.3. Research Objectives . 17

II. OPTICAL SENSOR. 19

2.1. Measurements With Infrared Sensor under Laboratory Conditions 20

2.1.1. Moisture Detection Experiments 21

2.1.2. Ice Detection Experiments . 23

2.1.3. Frost Detection Experiments 25

2.2. In-Situ Measurements With Infrared Sensor 28

2.3. Operating Experience. 31

2.4. Conclusions 32

III. HEATED RESISTANCE/TEMPERATURE SENSOR 33

3.1. Theory of Operation . 33

3.2. System Design: Surface Condition Detection. 34

3.2.1. Instrumented Concrete Slab . 35

3.2.1.1. Heater Design 36

3.2.2. Data Acquisition. 41

3.2.3. Thermocouples . 43

3.2.4. Control Units for the On/Off Heater Operation . 44

3.3. System design: Photovoltaic Power Supply 47

3.3.1. Power Supply Battery Pack 47

3.3.2. Photovoltaic System. 49

3.3.3. Charge Controller for Solar Modules. 50

3.4. System Configuration for In-Situ Measurements. 51

3.5. Field Deployment. 55

IV. EXPERIMENTAL RESULTS. 57

4.1. Laboratory Test Results . 57

4.1.1. Moisture and Ice Detection Experiments . 58

4.1.2. Reaction of the Sensor to the Frost Formation. 61

4.1.3. Snow Detection Experiments . 62

4.1.4. Conclusion 65

4.2. Field Test Results . 65

4.2.1. Behavior of the System 66

4.2.2. Presence of Moisture 70

4.2.3. Snow Accumulation Detection. 75

4.2.3.1. Snow Precipitation at Stillwater

Experimental Site 77

4.2.3.2. Snow Precipitation at Burbank Experimental Site 85

4.2.3.3. Snow Precipitation at Buffalo Experimental Site 87

4.2.4. Reaction of the Sensor to the Ice Formation 87

4.2.5. Frost Indication 89

4.3 Analysis Based on Experimental Results. 91

4.3.1. Sample Readings and Surface Conditions

Determined by the Program . 97

4.4. Field Operating Experience 101

V. SUMMARY, CONCLUSIONS AND RECOMMENDATIONS 105

5.1. Summary 105

5.1.1. Optical Sensors. 105

5.1.2. Heated Resistance/Temperature Sensors . 106

5.1.2.1. System Reliability . 106

5.1.2.2. System Accuracy. 107

5.2. Conclusions 108

5.3. Recommendations 109

REFERENCES 110

APPENDIX A SPECIFICATIONS. 112

A.1. Control Circuit Components 112

A.2. Temperature Controller Control Setup. 115

A.3. Control Circuit Modification 116

APPENDIX B COMPUTER PROGRAM 117

B.1. Program Source Code. 118