About The Bridge
The Brooklyn Bridge was built in the late 1800’s and was engineered by John A. Roebling, Washington A. Roebling, and Emily Warren Roebling. It is the first bridge to use pneumatic caissons and the first steel cable suspension bridge. The famous bridge is located in Manhattan, New York known around the world needing no introduction
Brooklyn Bridge 20 year Rehabilitation Plan
The goal of the project was long-term monitoring of the structural Health of the old masonry building on the Manhattan side of the Brooklyn Bridge approaches consisting of large masonry buildings for Roadway approach support. "Block A" and "Block B" main foundation are made of granite, concrete, stone and building walls are masonry with 3 story wood floors unique in design. These buildings are more than 125 years old and are beginning to show cracks from stress due to contouring and settling of the changing ground movements and load bearing walls. ChM4 is privileged to be a part of this 20 rehabilitation program, from the crack, acceleration, tilts and movement of vertical walls using optical sensors to assist in evaluation of new interior engineering design. The long term monitoring efforts for the approach spans where new modern piers and supports are built on the interior of these buildings support structure. By taking this approach the exterior of the building brick fa-sod stay intact as originally designed maintaining the historic bridges look. ChM4 is planning additional monitoring of approaches and suspension cable monitoring in the near future.
Block A and B Projects
The customer, NYCDOT and the University of Illinois at Chicago (UIC) using newly developed optical sensors chose ChM4 Inc. as the system integrator for "Block A" with assistance of UIC students to install the system. The project was completed in two phases to monitor cracks and settlement of "Block A" approach roadways using optical sensors. "Block A" was directly associated with the main Brooklyn Bridge suspension cables mechanical ground anchoring that could effect the building structure was also studied. With the success of the previous project a Phase 3 contract effort to monitor "Block B" was implemented to use Cleveland Electric Labs new optical displacement sensors to monitor cracks and building settlement. A Continuous 24/7 long term monitoring system contract was awarded to ChM4 to use our IntelliOptics® monitoring software implemented with virtual hosting using Azure cloud services.
Block B Approach Rehabilitation Program
ChM4 and Cleveland Electric Labs accomplished the Block B project jointly to Install and monitor critical spans in an effort to assist consultant design build engineers and State of New York Dept. of Transportation in determining the overall health and provide remote monitoring of the structure for future modifications. This information is used by engineering consultants to determine, prevent, and predict possible problem areas that need repairs through evaluation for placement of modern pier supports built inside the original structure. The overall enhancements will help demonstrate the capabilities of optical gauges to monitor accurate expansion of cracks that develop over time to determine the long-term rehabilitation efforts.
Model of Block B Brooklyn Bridge
The monitoring system has only one data acquisition instrument using the newest optical sensors available. The Model shown was used to determine displacement sensors and wall tiltmeter locations for the rehabilitation program in progress.
Sensor System Example Locations
Video of sensors locations in approach "Block B" and mounting examples. These are all passive optical sensors for tilts, crack displacement and temperatures.
IntelliOptics® structural health monitoring software, developed by ChM4 is a powerful, user-friendly interface that collects data from multiple sensor types and displays status information via one centralized program. Please Click on each page for a closer view. Also see our software section for more information and our Intelli-Insight® predictive analysis module for maintenance of critical structures.
Sensor System Design Drawings for Block B
ChM4 Design drawings of "Block B" sensor locations and mounting procedure for installation of optical sensors. The system included: (1) LUNA interrogator, (1) sm0416 multiplexer, (5) os4350 absolute temperature sensors for environmental reasons, (2) Fiber sensing tiltmeters, (2) FBG Korea Tiltmeters and (22) Cleveland Electric Labs short displacement sensors.
Sensor System Design Drawings for Block A
ChM4 Installation drawings of "Block A" sensors locations and mounting procedure of optical sensors. The system included: (1) LUNA interrogator, (1) sm0416 multiplexer, (5) os4350 absolute temperature sensors for environmental reasons, (5) Fiber sensing tiltmeters (22) UIC short displacement sensors and (5) UIC accelerometers.