Metro to monitor vibration levels at 80 spots on Yellow, Violet lines
The Delhi Metro Rail Corporation (DMRC) will soon start monitoring the vibration levels at 80 locations in the Capital to ensure that they stay within permissible limits in the underground sections of the network, said DMRC officials.
The monitoring of vibration levels will be done on two corridors: Yellow Line (Huda City Centre to Samaypur Badli) and Violet Line (Kashmere Gate –Raja Nahar Singh).
“This type of vibration monitoring helps in ensuring that track and rolling stock systems are performing within the defined parameters. The samples will be randomly collected from different locations to assess whether the vibration levels are within acceptable limits. If any variation is reported, then accordingly necessary steps are taken to mitigate the same,” said a DMRC official.
With the expansion of its network in the Capital, the agency has in the past received complaints from residents that they feel the vibration every time a train passes in the tunnel. In the past, residents of Saket, Hauz Khas, Begumpur, Shahbad Mohammadpur, Sarvpriya Vihar have raised the issue. Vibration is caused due to the interaction between the wheel and the rail track in underground stations.
According to Dr Nasim Akhtar, principal scientist at transportation planning and environment division, CSIR-Central Road Research Institute (CRRI) vibration above 72VdB (vibration decibel) can cause some discomfort to people. Akhtar said vibration on underground tracks is usually between 70-80 VdB, but on a soil base it gets killed. The vibration is amplified where the track has been laid on a rocky surface.
Akhtar said, “It is good that they are checking the vibrations at different locations. It is needed, especially in old systems, to identify areas on tracks or wheels, which require repair. The vibration levels are high in underground tracks near the curves. If the tracks are on rocky surface, then it will amplify the vibration level.”
DMRC officials said that the Metro has been regularly monitoring vibration levels.
“In the past, such monitoring has been carried out at locations such as Saket, Malaviya Nagar, Begumpur, Hauz Khas, Khan Market, Golf Links, Azadpur, Palam, Dashrathpuri, etc. DMRC since its beginning has taken adequate care to ensure that vibration levels in its underground section remain within permissible limits.”
DMRC officials said efforts have been taken to reduce vibration in the underground network constructed in Phase-I and II.
Anuj Udhrain, secretary of Hauz Khas Central RWA, said, “There are around 60 houses in the area which are affected by the vibration caused due to trains passing underground. The problem has aggravated over the past two years.”