Earthquake Resistant Architecture: Designing Safe and Resilient Structures
The after-shocks of the Kahramanmaras earthquake in Turkey and disasters closer to home, such as the Joshimath crisis, have made a global impact, compelling us to look closer into available engineering solutions for natural disasters and how to enforce them. Considering the current national and global events, safety concerns have driven architects to revisit earthquake-resistant designs. In India, earthquakes have been recorded throughout the nation’s history, ranging in intensity within different earthquake zones, from minor tremors to major ones of devastating magnitudes. The damage caused is not just by the motion of the ground causing vertical and horizontal movement, but also the after-effects such as landslides, floods, fires, and disruption to communication. Hence understanding the seismic history and threats of the locality and the ground you are building on is crucial for structural planning.
In highly seismic areas, construction entailing heavy debris such as masonry, particularly mud masonry and rubble masonry, should preferably be avoided since they factor into higher loss of life in the event of an earthquake. Besides general design considerations and codes, the NBC also specifies guidelines for specific structural members. Therefore, considering the vertical and horizontal loads during the earthquake and after-shocks entails minute technical guidelines that must be addressed.
The codes also regulate the requirements for detailing reinforcement in beams and columns, including joint faces, splices, and anchorage requirements. Provisions are also included for calculating design shear force and detailing transverse reinforcement in beams. This becomes essential considering how columns and beams form the core structural framework, and earthquake-related compressive and expansive forces can cause a myriad of damage, such as tears and cracks that jeopardise the entire building.
Earthquakes not only pose a threat to the users of a structure but also to the surrounding areas in case of a collapse. Deaths in the case of major earthquakes happen not due to the shaking of the ground directly but primarily due to debris and failing structures. This makes a compelling argument that architects and engineers have an irrefutable responsibility to create safer and stronger structures that can withstand earthquakes and other natural disasters while providing refuge during such perils, and the safest way to ensure structural stability and strength is by devotedly following building bylaws and codes to build resilient structures.