IIT-Mandi develops method to assess quake-prone buildings

Mandi, November 25

Researchers at the Indian Institute of Technology (IIT)-Mandi have developed a method to assess the ability of buildings in the Himalayan region to withstand earthquakes. The method is simple and allows decision-makers to prioritize any strengthening and repair work that must be undertaken to enhance a building’s resistance to earthquakes.

Will minimise bias

The computation process is designed so that it minimizes the possibility of human bias or subjectivity of the assessor in scoring a building. Sandip Kumar Saha, Assistant Professor, IIT-Mandi

Sandip Kumar Saha, Assistant Professor, School of Civil and Environmental Engineering, IIT-Mandi, has led the research while Ph.D student Yati Aggarwal has co-authored it.

Saha says, “The Himalayas are among the most earthquake-prone regions in the world because of an ongoing collision between the Indian and Eurasian plates. There have been periodic earthquakes that have been devastating for these regions in terms of both lif77e and property loss. The Great Kashmir Earthquake of 2005 killed over 1,350 on the Indian side, injured at least one lakh people, ruined tens of thousands of houses and buildings, and rendered millions of people homeless.

He says, “Earthquakes cannot be prevented but damage can certainly be prevented through the design of buildings and other infrastructures that can withstand seismic events. The first step for ensuring safety of existing structures from earthquakes is to assess their current vulnerabilities and strengths. Rapid visual screening (RVS) of buildings is often performed to assess the vulnerabilities of buildings at a large scale. The RVS uses visual information to decide if a building is safe to occupy, or requires immediate engineering work for enhancing earthquake safety.”

Saha says, “We have devised an effective method to screen reinforced concrete (RC) buildings in the Indian Himalayan region so that repair work may be prioritized according to the condition of the buildings and the risk from impending earthquakes can be minimized.”

He says, “Through extensive field surveys, researchers have collected a large amount of data on the types of buildings present in the Mandi region of the Himalayas and typical attributes present in these buildings that are connected to their earthquake vulnerability. A numerical study was also carried out to establish guidelines for counting the number of stories in hilly buildings for their RVS. Further, based on the vulnerable characteristics present in the buildings, an improved RVS method was proposed.”

He says, “The methodology developed for screening buildings is a simple single-page RVS form that does not require much expertise to fill. It takes into account various vulnerability attributes that are unique to buildings in the case study region.”

“Calculations made using these observations produce a seismic vulnerability score for buildings, which differentiates vulnerable buildings from the more robust ones, and allows better decision-making for maintenance and repair. The computation process is designed so that it minimizes the possibility of human bias or subjectivity of the assessor in scoring a building,” added Saha.