Kochi: As the demolition day of the four apartment complexes at Maradu in Kerala's Ernakulam district is fast approaching, fear is at large that the large scale demolition will adversely affect the neighbouring homes. According to Dr Anil Joseph, member of the expert technical committee overseeing the process, the buildings would collapse at an angle of 37 degrees.
Meanwhile, a team from the Indian Institute of Technology (IIT) Madras would study the effect of the vibrations caused by the demolition on the neighbouring houses. The study will conducted in a radius of 200 m. The IIT team would be present at the spot during each demolition to record the magnitude of the vibrations using special computers.
The impact of the demolition on neighbouring houses will depend on the magnitude of this vibration. The movement caused to the earth during the demolition is termed ‘peak particle velocity’ which is measured as millimetres (mm) per second. Vibrations up to 25 mm per second would not affect neighbouring houses. However, if the level reaches 50 mm, the houses may feel the impact. In case the level is above 100 mm, the buildings have a good chance to suffer severe damage. The advice of the experts from IIT would be sought to minimize this damage.
The distance of the houses from the demolition spot would be the key factor deciding the impact on them, said Anil. Measures like digging moats or pits would be adopted to prevent the vibrations from spreading with the same force, he added.
An apartment building weighing over 20,000 tonnes will not be brought down at one stretch but in several stages through controlled explosion. As a result, only materials weighing 1,000-1,500 tonnes would fall to the ground each time, thereby minimizing the impact.
All the apartment buildings would be demolished using the same method and the angle of debris collapse is expected to be 37 degrees, informed Anil. The twin towers of Alfa Serene apartments would collapse in the space between them and H2O in the direction of the Kundannoor-Thevara bridge.
“After the topmost floor crumbles to the ground, the pile of debris would be only 18 m high. This would neither affect the nearby houses or the bridge. However, all precautions are being taken as such a demolition is being carried out for the first time in Kerala, “ said Anil.
Worried neighbours
On the sidelines, authorities are conducting inspections at the nearby independent houses to assess the cracks reported. A report in this regard would be ready soon, said Anil.
While the authorities are engaged in hectic preparations for razing the apartments, residents of nearby independent houses are panic-stricken. Many have shifted from the locality. Most of the remaining residents say that they are struggling to find rented houses. Steep rent demanded is another hurdle, according to them.
CPI district secretary P Raju visited the area and demanded compensation for the damage to the houses. This amount should be collected from the builders and the court has to issue a directive to the Justice Balakrishnan Commission in this regard, Raju added.
“The apartment located in a thinly-populated area should be demolished first,” he suggested.
The Supreme Court had earlier this year ordered for the demolition of the apartment complexes, which were built by violating the Coastal Regulation Zone (CRZ) norms. Though the flat owners filed petitions against the SC order, the top court did not entertain these. The apartment complexes would be demolished on January 11 and 12, 2020.
