Experts from IIT-Madras who inspected the two churches that developed cracks due to Metro Rail work said the cracks would not pose any serious threat to the buildings.
Two heritage structures, 152-year-old CSI Tamil Wesley Aalayam and 121-year-old Arcot Lutheran Church, developed cracks a week ago, when tunnelling work for Metro Rail was being carried out underneath the churches on the Mannady-Madras High Court stretch.
Prof. S.R. Gandhi, head of department of civil engineering, IIT-M, who inspected both the churches said, “In CSI Tamil Wesley Aalayam, there are cracks as wide as 10 mm only in one or two locations. The rest of the cracks are about 2-3 mm wide. In Arcot Lutheran Church, there are minor cracks.”
The experts have recommended further examination of the foundation of both churches and tests to see if the ground under both buildings can receive the cement grout.
“If the ground receives grout, it will become hard and not permit further settlement of the building, and ensure the building is safe. The buildings will be constantly monitored till the tunnelling work is complete,” he said.
The buildings were surveyed before the tunnelling began, Mr. Gandhi said. However, when there is major construction activity, slight disturbances may occur in ancient buildings. But the cracks that developed on the two churches were not serious and would not affect the stability of the buildings, he said.
“The tests proposed by IIT-M may be carried out in a few weeks after strengthening measures on the churches are over. But the foundations will be studied before the second tunnel boring machine (TBM) begins work,” Mr. Gandhi said.
Meanwhile, the authorities of CSI Tamil Wesley Aalayam said they proposed to approach structural engineering experts from Anna University to inspect the church again. “We feel a second opinion is essential for the safety of the building,” said a church official.
CMRL officials said they may wait till they reach a consensus with the church authorities on the restoration work to be carried out.
“This problem may not arise when the second TBM drills through the area because it will be 15 metres away from the first TBM and by the time, the ground would have settled,” said the CMRL official.