Autonomous Crack Comparometer
Damian Siebert
Advisor: Prof. Charles Dowding

Presentation Outline
Background
Current Research, Phase I
Future Work, Phase II & III

Problem
Need a new approach in vibration monitoring
Current practice
Measure ground motion and compare with house damage from past studies
People see cracks in there houses
Don’t understand ground motion
Despite past evidence difficult to convince

Solution
Create a system that will:
Measure change in crack width due to both long term and dynamic effects
Compare changes in crack width with temperature, humidity, and dynamic excitation
Comparison should be
Accessible easily to general public
Regenerated often
Graphically presented

Factors Influencing Crack Movement

Factors Influencing Crack Movement

Crack Width Change

Current Research, Phase I
Hardware
Automation of System
Test House Data
Web Site

Hardware

Sensor Employed
LVDT’s

Sensor Problems
Electronic Drift
Thermally Induced Hysteresis

Sensor Problems

Sensor Correction
Null Sensor
Near-by but not Across the Crack

Sensor Correction

Sensor Correction

Slide 16

Test House

Sensor Locations

Results

Results

Results

Results

Web Design Requirements
Graphical Interface Easily Understood by the Lay Public
Quick Loading
No Scrolling
Consistent Feel
Viewable on any browser
Compatible with older computers
Easily Extensible
New Pages will be added in the Future

Web Display Components
Background Information About Crack Movement
Location
Sensors in House
House in Neighborhood
Weather Information
Temperature
Humidity
Crack Displacement Information vs.
Weather
Vibration

Conclusions
Crack Width Changes are Effected
Most by Weather
Humidity
Temperature
Moderately by Habitation Vibrations
Near by – walking down stairs
Far away – slamming a door across the room
Least by Construction Vibration
Blasting
Pile Driving
Etc.
System that Works!!
Autonomously Records, Analyzes, and Displays Data

Future Work, Phase II Hardware Changes

Future Work, Phase III Hardware Changes

Future Work
Sensors
More Research Into Better Sensors
Web Improvement
Security
Web Interactive Components
Graphical Tutorials
Self Guided Tours of Background Information
Addition of Blast Induced Vibration
Transducers
Additional Programming
Give out URL to a Community
Feed Back