Analysis of the Dome of India’s Presidential Residence

The Rashtrapati Bhavan or the Presidential Residence on Raisina Hill in New Delhi is an iconic structure designed by Sir Edwin Lutyens in the Indo-Saracenic style and completed in 1929. The structure is made of brick masonry, sandstone cladding, lime and reinforced cement concrete. This paper gives an insight into the investigative process that was followed to determine the causative mechanism of the observed structural distress in the inner dome of the central double-dome of the Rashtrapati Bhavan. During the visual scrutiny of the building, a crack of significant dimension in the north-eastern niche of the domed hall and a small crack in the diametrically opposite niche were detected. In order to evaluate the severity of the observed cracks, a systematic and holistic approach that comprised of historical and geometric surveys, assessment of the sub-structure morphology and the use of relevant non-destructive and minor destructive tests on the superstructure was adopted. The findings from the above-mentioned sources, served as valuable input for the finite element model of the structure, that was developed using DIANA. The non-linear gravity and pushover analyses conducted on the model confirmed the speculation made on the basis of the visual and geometrical assessment, that the opening of the stairwell in the vicinity of the affected niche presents an inherent weakness at the drum of the dome. The paper describes the in-situ tests, relevant structural features for the numerical analysis, modelling aspects and the results from the analysis.