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Proceedings of the International Conference on
Advances and New Challenges in Earthquake 603
Engineering Research, Hong Kong Volume
SMART HEALTH MONITORING SYSTEM
OF A PRESTRESSED BOX GIRDER BRIDGE
Xuan Wang,
Ming L. Wang
Dept. of Civil and Material Engineering
University of Illinois at Chicago, 842 W. Taylor St
Chicago, Illinois 60607, USA
ABSTRACT
With increasing technology, many non-destructive testing methods have been developed for the health
assessment of bridges. These methods range from the simplest ones that cover regular inspections and
visual controlling to highly sophisticated methods that require expensive equipment and highly skilled
personnel. This paper presents experiences gained from the health assessment of a pre-stressed boxgirder
bridge. Dynamic and static methods, including two load tests, were used in evaluating the
bridge's health. From these experiences, a new Smart Health Monitoring System was developed and
applied in the real-time health monitoring of the Box-girder Bridge. Because this new system can preprocess
all the raw data from each sensor, it improves largely the efficiency of data analysis. Also, it's
able to supply the real-time health status of the bridge and all the statistical data on-line.
1 INTRODUCTION
The rating of damage severity should be based on how much the damage influences safety of the
structure. Besides defects that directly threaten structural safety, there are damages that do not hinder
proper performance of the bridge under normal traffic conditions but they decrease its safety margin,
which means that the structure does not have required reliability. In such cases, possible overloading
like traffic congestion may lead to the collapse. There are also some damages associated with
durability that accelerate the deterioration processes in structural materials and finally may cause
serious failure. An example is cracking in prestressed concrete structures exposed to severe weather
conditions that may lead to the corrosion of prestressing reinforcement, reduction of steel area and
finally rupture, e.g. sudden collapse of Bickton Meadows footbridge in Hampshire, UK in 1967 caused
by corrosion of prestressing tendons. Traditional monitoring method is to measure the responses of a
bridge periodly. It can't find and respond to any emergency happened on the bridge. And the raw data
collected from various kinds of sensors is too much to be analyzed easily. Hence, engineers need a
kind of new smart health monitoring system that can show the real-time health status of bridges. Also,
the new system can preprocess all the raw data and calculate daily, weekly, monthly or annual
statistical data.