Noida high-rises can be quake proof if designs are followed
Residents of Noida and Ghaziabad residing in high-rises need not fear for their safety if all buildings are engineered as per specifications under the building bye-laws.noida Updated: May 06, 2015 19:38 IST
Residents of Noida and Ghaziabad residing in high-rises need not fear for their safety if all buildings are engineered as per specifications under the building bye-laws.
Placing the recent earthquake that hit Nepal in context, structural engineer Dr Rajeev Dua said that the engineers and builders should learn from the damage incurred to structures in Nepal.
Dr Dua referred to Sanogaucharan in Kathmandu city, where the impact of the April 25 earthquake was maximum.
While most of the buildings in the surrounding area had collapsed completely or partially, one 16-storeyed structure - KL Residency (ground, two basements and 13 floors) had only experienced cracks on the boundary wall.
"Although the structures of all high-rise buildings are designed to sustain tremors as per the sensitivity of the earthquake zone, execution of the project is very important," said Dr Rajeev Gupta, structural engineer.
Dr Dua, who has designed a number of buildings in Delhi and NCR and also the KL Residency in Kathmandu, has a degree in engineering, a Masters and a doctorate in 'Response Control of Tall Buildings Subjected to High Intensity Earthquakes' from IIT-Delhi.
He said that the KL Residency was constructed by the KL Dugar Group about two years ago, and everything suggested by him, including the need for close monitoring of the project in the construction stage.
However, Dr Dua also said he was by no means saying that all tall buildings are safe from earthquakes. He referred to the heavy damage caused to high-rise buildings in Nepal that were now not fit for living.
"The use of steel is detrimental to the health of structures. One of the differences between KL Residency and other damaged buildings was the use of steel. Unlike the myth, there were almost half steel per square feet used in KL Residency in comparison to that of damaged high-rises. In addition, the builder of KL Residency monitored the project himself to execute the structural design," said Dr Dua, a topper throughout his academic career, including in the IIT joint entrance examination.
During his 30 years of professional practice, Dr Dua recalled the many instances when developers requested him to change the structural design to sell more space.
"Construction of earthquake-resistant buildings require more money. Although builders pay hefty sums to an architect, they are shy about consulting a structural engineer to save money, and thus, rely on the old practice of using more steel making them heavier," structural engineer said.
Unlike tall buildings, a majority of homes in the NCR (stilt + 4 storeys) are unengineered. The chances of these houses getting damaged are higher during earthquakes.
"The planning and architecture department of the Greater Noida authority is short staffed and has hardly four-five engineers to look after hundreds of residential and commercial projects. They cannot deal with thousands of files in details that come for their approval," said an official of Greater Noida authority requesting anonymity.
"These days, most of the real estate developers don't want a negative image. If you are not monitoring your project, you can be cheated any time. For example, I had been following a leading cement manufacturer, who supplied sub-standard cement. The cement failed the strength test. This was not possible if you are not monitoring the project keenly," said Nikhil Hawelia, the managing director of a real estate company.
Meanwhile, CONRWA has said that the provision of RCC shear wall should be included in the real estate regulatory bill as an anti-earthquake measure. "Since the earthquake forces are horizontal in nature and change their direction every second, the more effective method to resist them is to provide RCC shear wall right from the bottom to the top across the width of the building. RCC shear walls absorb the horizontal forces of the earthquake," said Col TP Tyagi, convener, CONRWA.