‘Stay safe, go in for seismic retrofit and upgrade’
Part-II of our safe building series focusses on assessment and awareness of the safety category of structures SAFETY FIRST
The earthquakes on April 25 and May 15, both above magnitude 7, and continuing aftershocks in Nepal, which were also felt in India, have intensified the debate on structural safety in the subcontinent. HT Estates, which has regularly reported on the state of buildings in India and the need to retrofit and reconstruct damaged or weak structures, once again underlines the importance of knowing more about earthquake resistance grades of buildings.
There are reasons for worry, says Sandeep Donald Shah, country head of, Miyamoto International, an earthquake and structural engineering firm, whose PIL last year led to the Supreme Court ordering the government to ensure that all real estate projects in the country clearly display their respective earthquake-resistant grade, along with clear meaning of the category as defined by the government. The Indian seismic code, which Nepal largely follows, covers only the last category of earthquake resistance, which is ‘collapse prevention.’ In India 100% of the buildings, including hospitals and highrises, are designed and built only to the collapse prevention standards. This level is for buildings, the contents and utilities of which, when shaken severely, suffer major damage. The building does not have any additional reserve capacity, is in the state of imminent collapse, and cannot be used after the earthquake.
As the buildings in Nepal too were designed and built to the collapse prevention standards these suffered extensive damage. “If you read the definition, the damage is said to be beyond repair,” Shah explains.
Important buildings and high-rises have to be built to
Important buildings and highrises have to be built to ‘immediate occupancy’ standards.
Difference of costs between ‘collapse prevention’ and ‘immediate occupancy’ is approximately ₹ 350 per sq ft
The buildings in Nepal were designed and built to the collapse prevention standards and suffered extensive damage
‘immediate occupancy’ standards. This is defined as a building, its contents and utilities, despite being shaken predominantly in their linear range of behaviour, sustain only minor damage. The use of prevailing functions of the building and facilities is not restricted after the earthquake so that its functioning can be resumed immediately after the earthquake.
Difference of costs between ‘collapse prevention’ and ‘immediate occupancy’ is approximately ₹ 350 per sq ft.
There are two main Indian seismic codes, of which IS-1893 has not been updated for 13 years and IS-13920 has not been updated for 22 years.
The first ( and top- rated) earthquake- resistant build- ings categories are, as per the Government of India document which is also in line with international definitions, is the ‘fully operational level’, when despite the building, its contents and utilities being shaken by an earthquake, no damage occurs; the function of the building is not disrupted due to the occurrence of the earthquake.
‘Life safety level’ of earthquake resistance is defined as the building, its contents and utilities being shaken severely in their nonlinear range of behaviour. Significant damage occurs in them, but the building remains within its reserve capacity and does not reach the state of imminent collapse. The use of the facility is restricted after the earthquake until detailed structural safety assessment is performed to ascertain the suitability of the building for retrofitting. If found suitable, the building may be retrofitted.
What is the way out for people living in high-rises in which no category has been specified? Shah says his advice to them would be to go in for seismic retrofit and seismic upgrade without waiting for another earthquake to strike. “It is also much less expensive and safe,” he adds. This fear loomed large in the minds of several political and market analysts since the time Modi came to power. The highly centralised appearance of the government has moderated in recent times with decentralisation of power to cabinet members and states’ chief ministers. “We agree that power should be further de-centralised to the grassroots level (ie district and panchayat level authorities) and this further downward percolation of power may take another year or two,” says the white paper.
Suspecting that the Noida Authority had allowed Jaypee or Mahagun to amend original layout plans, the Bhatlas then filed the writ petition in the Allahabad High Court, arguing that “before amending the original sanctioned plan, prior permission of the intending purchasers should have been taken as required under the UP Apartment (Promotion of Construction, Ownership and Maintenance) Act. So any alteration/amendment in the original plan is illegal.”
Much to the surprise of the As the definition of smart cities given in the note released by ministry of urban development is too broad, different agencies have had different interpretation of the concept. Even though the union cabinet has cleared the Smart Cities Mission and allocated ₹ 48,000 crore, there is petitioners, Noida Authority informed the court that it had neither revised nor amended nor sanctioned any fresh layout plan in the Jaypee Greens Group Housing Society. The petition had also made a plea to quash the amended plan but no argument over the matter took place as the Authority said in court that it had not amended the original plan. “Under the circumstances, the allegations made by the petitioner that the initial layout plan has been amended by bifurcation/division/alterna-
tion doesn’t stand. That be so, we don’t find any merit in this petition warranting interference in writ jurisdiction,” the court ordered.
The Kristal Court homebuyers are satisfied by the order, but the bigger question now is how the developer Mahagun advertised a layout plan not approved by the Noida Authority.
“I f we go by t he Noida Authority’s version, Mahagun Manorial is basically four towers of Krystal Court – two with G+20 and two others with G+26 floors. However Mahagun Manorial’s brochures showed six towers each with 45 storeys. There is a big film star promoting the project. What if someone buys an apartment there? Isn’t such an advertising misleading the homebuyer as he might lose his money investing in a project for which no Authority approvals have been acquired?” asks Aviral.
Homebuyers are also questioning why the Noida Authority has not taken any action against the developer. “When allottees of Kristal Court can notice the misleading advertisement, why can’t Noida Authority do so? Under section 4 (1) of the UP Apartment Act 2010, it’s an offence to launch any project without getting its layout plan approved,” he adds.
Efforts to get a reaction from Noida Authority proved futile.