English | Français


Near Kingston, ON Canada

The Thousand Islands Bridge  is one of the larger bridges crossing the border between Ontario and New York state in the United-States. Built in 1937, this bridge sees over 2 million commuters each year travelling through the Lansdowne border station.

The entire bridge spans 13.7km and is a hybrid-suspension bridge featuring very active expansion joints. Due to the large amount of traffic and its structural tendency to move, Transport Canada alongside the Federal Bridge Corporation LTD. approached Sensequake to test the bridge.

The 500m section we evaluated proved to be a challenged due to its long structural shape. Our 3 day sensing test was therefore designed specifically with its span in mind and long data collection times were used to achieved relevant results. This test included:

  - Defining a baseline for the bridge

  - A global test of the bridge

  - Sectional tests between the side and central spans

  - Joint tests at the compression joints throughout the bridge

All modal properties were examined through the post-processing of the data. These include the natural frequencies, the damping rations and the mode shapes of the entire bridge.

Additionally, the reactions between the compression joints were examined separately to identify the interaction between the sections. While the finger joints exist between the main and side spans of the bridge, they are attached by the steel cables. Sensequake therefore had to create a specialized test to take this into account and properly examine the behaviour of between the side and mid spans of this bridge.


Copyright © 2020