CHENNAI: In an attempt to ensure safety of motorists travelling on bridges across rivers, the State highways department is to install sensors to monitor deterioration level and stability of bridges on real time basis.
The sensor-based structural health monitoring system is to be fitted first on the bridge on Adyar river at Ekkatuthangal in Jawaharlal Nehru road by January. The bridge was built in 1993.
According to official sources, the quality assurance and research wing of State highways is to collect data on the stability of the bridge, under Tamil Nadu Innovation Initiative (TANII) scheme.
“The sensor-based structural health monitoring system will provide data on deterioration level of a bridge. Thus, we can assess the possible damage the bridge will suffer in the next few years and accordingly plan for strengthening it and other retrofitting measures,” V Geetha, Chief Engineer, Quality assurance and Research, State highways told Express.
Presently, State highways identify damages in bridges through visual and physical inspection. Signs of deterioration in bridges surface as they progress.
However, highways is unable to detect the defects in the structure since all critical locations cannot be accessed. As a result, the strength of the bridges cannot be assessed quantitatively.
Official sources said as part of the project, highways will install five different types of sensors at critical locations on the bridge.
“The GPS enabled electronic device will observe the thickness of the structure, physical damage and other vital measurements which indicate deterioration level of structure and transmit data through a communication network. By analysing the data through a software platform, the location and severity of deterioration and damage can automatically be assessed on a real-time basis,” explained a senior highways official.
According to highways policy note, the State has 8639 major and minor bridges. Bridges having a length of above 60 metres are classified as major. While building a new bridge, though its lifespan is not predetermined, highways sources said the lifespan of major bridges is 70 to 100 years depending on various factors.
“The bridges will deteriorate with time due to ageing of materials, unfavourable environmental conditions and sudden increase in the volume of vehicles. All the river bridges are likely to be covered under this programme,” sources said.
Fact file:
Sensors to be installed at critical locations of a bridge.
Sensors will observe thickness of structure and physical damage, transmit data.
Data will help plan strengthening and other retrofitting measures.
Presently, damage in bridges is identified through visual and physical inspection.
Bridge across Adyar river at Ekkatuthungal on Jawaharhlal Nehru Road built in 1993.
Project to be taken up under Tamil Nadu Innovation Initiative (TANII) scheme.
State has 8,639 major & minor bridges.
Bridges above 60 metres length are major bridges, built mostly across rivers.
Bridges with six to 60 metres length categorised as minor.