It’s hard to imagine urban development without construction projects, which include everything from blueprint planning to implementing geotechnical instrumentation. However, in the wake of such projects, pre-built structures, especially bridges, can very easily be subject to damage or destruction.
This is where a bridge monitoring system comes into the picture. Using modern technology, this system is utilized to gain critical information about a bridge’s structural health, before, during, and after a construction project. Consequently, any risk or hazard to the bridge is avoided, using analytical data to take measures beforehand. This not only helps to protect the structure but the vehicles and commuters using it as well.
Bridge Monitoring Systems – A Brief Overview epoxy-repaired
So, how exactly does bridge health monitoring work? As mentioned above, analytical data plays a major role here, allowing analysts and engineers to study a bridge’s structural integrity during construction. Having said that, this also involves numerous aspects that work together like a well-oiled machine for successful bridge monitoring. Apart from adequate manpower, these primarily include geotechnical instrumentation, monitoring solutions, and web management systems.
At Encardio Rite, here’s what we provide for expert-grade bridge monitoring: –
- Pressure cells, strain gauges, vibrating wire crack meters, and other vibrating wire instruments to measure strain and displacement
- Load cells to assess force
- Vibration monitoring for acceleration measurement
- Tiltmeters, inclinometers, beam sensors, and other MEMS technology-based sensors measure a bridge’s tilt or inclination.
Rite Geosystems Inc., the Encardio Rite counterpart in the USA, worked on five such bridge monitoring system projects. These included both pre-made and under-construction structures which required monitoring and instrumentation for seamless project completion. The monitoring solutions we equipped, helped in obtaining a 360-degree overview during each project, aiding in thorough monitoring.
| Also Read Structural Health Monitoring: Instrumentation & Monitoring During Construction |
Moreover, we’re especially proud of these projects as they involve the top 5 famous bridges in the USA, and it’s always good to see our contribution’s fruition in reality. Let’s take a look at a detailed account of each monitoring project and its key insights.
1. Harry W. Nice Memorial Bridge
Also known as the Potomac River Bridge, the Governor Harry W. Nice Memorial Bridge is located in Newburg, Maryland, USA. Spanning 10,050 ft across the Potomac River between Maryland, Newburg (Charles County), and Dahlgren (King George County), Virginia, the bridge had 59 lower approach bents, each spaced at 61.5ft. Plus, there were 19 raised piers and spans, spaced from 116 to 800ft.
Foundation Test Group, the project client, entrusted Rite Geosystems Inc. with providing a robust bridge monitoring system for the Potomac Bridge during pre-construction baseline monitoring and construction. Here’s what our scope of work was: –
- Supplying geotechnical instruments
- Compact dataloggers for automatic monitoring
- Robotic total stations for automatic survey
- Online WDMS (web-based data management system) with pre-set alarms
- Daily, weekly, and monthly reports (auto-generated)
Instrumentation
| For Existing Bridge Monitoring: |
| Strain gauges | Used on trusses and girders to measure strain |
| Tilt meters | Used on decks and trusses to measure rotation/tilt |
| Crack meters | Used on the epoxy-repaired piers and to monitor existing cracks, if any |
| Prism targets | Used on decking, girders, trusses, and piers, to monitor X-Y-Z movements |
| Dataloggers | Provided GSM/GPRS modem-equipped automatic compact dataloggers |
| ATS | Provided ATS (automated total station system), along with an in-house developed control box, equipped with GSM/GPRS, and other software for remote station control |
| For Monitoring Construction Works of the New Bridge |
| Piezometers | Used to monitor pore water pressure and groundwater level at the land-based foundation construction |
| Borehole extensometers | Used to monitor sub-surface settlement of underground structures and critical utilities near the construction site |
| In-place inclinometers | Used to monitor the lateral movement of adjacent structures, retaining walls, and embankments. This helped in verifying that movements were within the project’s design tolerances. |
| Settlement points | For the settlement monitoring of embankments and other adjacent structures to see if movements were within the project’s design tolerances |
Results
The monitoring was done using the above-mentioned instruments and Rite Geosystems Inc.’s online cloud-based monitoring system. The tiltmeters, strain gauges, and numerous other sensors were installed on the existing bridge. Real-time data from these were accessible to the contractor/consultant during construction. This paved the way for safe and secure construction work without any damage, failure, or delays.
2. I-78 Easton Road Bridge
The I-78 dual-road bridge, located on Interstate 78 near Bethlehem, Pennsylvania, USA, was in dire need of rehabilitation. Thorough inspections over the years indicated rotation and settlement of the MSE walls, and abutments to the bridge. Recent inspections also showed separations between the bridge and MSE walls.
Pennsylvania Department of Transportation, District 5, and the American Geotechnical and Environment Services Inc. (AGES) had entrusted Rite Geosystems, Inc., to monitor the rehabilitation work on the bridge’s issues and deficiencies. Plus, we were also responsible for investigating the movement pattern of the east and westbound bridge abutments. Here’s what the scope of work included: –
- Providing geotechnical instruments
- Installing geotechnical instruments
- Using compact dataloggers for automatic monitoring
- Providing online WDMS with pre-set alarms
Read more: Bridge Monitoring Sensors: Types and Applications
Instrumentation
| In-place inclinometers | To monitor sub-surface lateral movements, i.e., deviations from the vertical in two axes (bi-axial deformations) |
| Multi-point borehole extensometers | To monitor sub-surface deformations (heave or settlement) of rock/soil layers at varying depths within the rock/soil body |
| Dataloggers | GSM/GPRS modem-equipped compact wireless dataloggers (automatic) to transfer all record data to remote PCs/servers |
| Piezometers | To monitor groundwater levels and pore water pressure at the project location Multi-level vibrating wire piezometers were installed for monitoring pore water at various depths. |
Results
Using our completely online cloud-based data management solution and supplied instruments, AGES and the Pennsylvania Department of Transport were able to undertake their rehabilitation project. All the stakeholders were able to access data collected by the wireless dataloggers and sent to the remote PC/server, helping them with hassle-free bridge health monitoring.
3. BR 1-159 Bridge
Located in New Castle County, Delaware, USA, the existing BR 1-159 Bridge had compromised structural integrity, especially due to inoperable moving parts. Its steel superstructure also exhibited massive corrosion and section loss. Hence, the project stakeholders decided to conduct a replacement project to construct a new, 5-span, 393’-11 ⅞” bridge on James Street, right over Christina River.
At Rite Geosystems Inc., we were entrusted to monitor the sub-surface soil conditions surrounding the 72-inch CRFM (Christina River Force Main) concrete sewer pipe. The scope of work included the following: –
- Supplying geotechnical instruments
- Automatic monitoring with data loggers
Instrumentation
| In-place inclinometers | To monitor biaxial lateral soil movement and check if the movements surpass design tolerances |
| Data loggers | GSM/GPRS modem-equipped automatic data loggers |
| Piezometers | To monitor pore water pressure |
Results
Our instrumentation was installed successfully, allowing the project owners to monitor the structure whenever needed. This further helped them complete the bridge health monitoring system project, hassle-free.
4. East Midtown Greenway Project
Located in East Midtown, USA, the ambitious East Midtown Greenway Project is envisioned to complete the Manhattan Waterfront Greenway’s space, along the East River. The project is set to be completed by fall 2023 and includes the construction of the esplanade’s northern section, which connects 62nd Street’s Andrew Haswell Green Park.
The project will also include a pedestrian bridge towards East 54th Street, a bike path, a walkway, numerous light fixtures, watering stations, irrigation systems, and tub girders for soil installation. The E-54 bridge is going to be a concrete and steel pedestrian bridge, spanning from Sutton Place Park, over FDR, and onto the esplanade, via a pile-supported structure.
At Rite Geosystems Inc., we were entrusted to provide the required instrumentation to monitor changes in the existing tilt and cracks across the retaining wall, which occurred due to construction. The scope of work included the following: –
- Supplying geotechnical instruments
- Data loggers for automatic monitoring
Instrumentation
| Crack meters | To monitor existing cracks on FDR’s retaining wall and columns |
| Tiltmeters | To monitor the retaining walls’ angular distortion, along the Andrew Haswell Park, and/or the FDR columns |
| Data loggers | GSM/GPRS modem-equipped automatic data loggers to gather and transfer data to central servers |
Results
Upon installing our instruments, the client could access vital information to complete the project seamlessly. Moreover, we also provided the client with our tiltmeters to be used in the future. Hence, they can continue monitoring the angular distortions of the retaining walls, and/or the FDR columns.
5. Malcolm X Bridge
Maryland’s $5.6 billion dollar Purple Line Project is currently under construction, set to be substantially completed by 2022. While the project aims to connect numerous communities across Maryland, it has a minor hurdle to overcome. The Malcolm X Bridge, one of Maryland’s prominent overpass bridges, fell right into the potential influence zone of the construction.
Hence, Fugro USA Land Inc., the project client, and Maryland Transit Authority, the owner, entrusted Rite Geosystems Inc. to monitor the bridge during pile foundation construction. The scope of work was as follows: –
- Supplying geotechnical instruments
- Providing compact data loggers for automatic monitoring
- Online WDMS (web-based data management system) with pre-set alarms
Instrumentation
| Biaxial tiltmeters | Installed along the bridge to monitor any sort of deformation occurring due to construction activities |
| Data loggers | GSM/GPRS modem-equipped automatic data loggers to collect data from tiltmeters and send them over to the DRISHTI WDMS |
Results
The instruments provided helped in creating an all-around bridge monitoring system for the Malcolm X Bridge. We also provided our DRISHTI WDMS for over six months, providing the stakeholders with a transparent overview of the bridge’s conditions. All alarm notifications were sent via email and SMS.
| Also Read Instrumentation and Monitoring for Risk Assessment – Malcolm X Bridge Case Study |
In Conclusion
So, that’s all on our extensive work on the top 5 bridges across the USA. Using our best-of-breed instrumentation and monitoring solutions, we successfully maintained our benchmark in providing the top-most Geotech services.