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The Smart Monitoring System (SMS) was developed by the Bridge Research Center at the University
of Illinois for IDOT under the title Development and Installation of a Permanent Health Monitoring
Station for the South-Bound Kishwaukee Bridge. This paper describes the following aspects of the
monitoring system that were developed as a part of this project: capabilities, sensors and locations, and
analysis. The analysis of data obtained from the installed system reveals the health condition of the
bridge between December 2001 to March 2002. The system consists of a rack-mount UNIX-based PC
(top rack) which controls a multi-function data acquisition card and modem. Signal conditioning
modules and anti-aliasing filters are contained in a separate enclosure (lower rack). The diagram of
SMS was shown in Figure 1.
Bridge Computer Station
Software Functions
1 Process
J Diagnostic
Algorithms
Hardware Functions
, Acquisition
•decimated data stream
updated hourly
•inferred bridge status
updated daily
UIC Computer Station
Hardware Functions
Software Functions
temperature
iocal strains
crack displacements
acceleration (freq.)
video snapshots
IDOT
Computer
Station
• system status
• video frames
• daily monitoring status
• low-bandwidth data
available in spreadsheet
format
Wired
Ethernet
Standard
Windows
PC
Fig. 1 Schematic Diagram of Smart Monitoring System
The objectives of Smart Monitoring System (SMS) are to monitor and evaluate the structural health
status for Kishwaukee River Bridge, and to provide information for facilitating the inspection and
maintenance activities. The SMS can collect and preprocess the raw data of structural responses such
as strain, crack opening displacement and acceleration, in order to:
1) Characterize the temperature influence on strain, crack opening displacement, and acceleration.
2) Characterize the traffic-related inputs and responses.
3) Establish the global frequencies of the structure.
4) Provide the information on presence and extent of crack growth and state of shear reinforcement in
the web.
5) Provide the global information useful for FEM model updating (important for damage sensitivity).
6) Locate regions that require more in-depth scrutiny through diagnostic tests and determine
additional locations that require continuous monitoring.
7) Provide information that will aid the owner and maintenance authority to make rational decisions
when assigning the maintenance and repair budget.
2 DESCRIPTION OF THE BRIDGE AND SENSOR LOCATIONS