Excerpt from an interview with Ar. Raj Rewal, New Delhi, 27th October 2017

Q – Nirmal Kulkarni – What were the challenges presented in the design of building a space-frame in RCC, especially in view of the technological innovation which it sought to be?

A – Raj Rewal – This was an architectural competition and the client wanted a permanent exhibition complex. It had to be a unique design signifying the 25th year of our Independence and this was emphasized by Ms Pupul Jaykar and Mr. Ramadorai. In those days we had very limited means, nothing could be imported, so the design was envisaged within those constraints. So we thought that why not build an extremely large span structure, (the brief also required that even an Air force aircraft could be housed) which we can be proud of. The design of lattice structures or jalis and the triangular geometry has its base in ancient Indian past in the yantras, later on also explored by the Mughals, and we picked up that motif.

I had worked in Paris on steel space frame structures. I thought to myself as a young architect that since the Indian sun is so strong why not design a structure where the roof and wall is one seamless surface of sun-breakers. So the idea was that whole structure, because of its large span (256’X256’) had to be designed to be 16’ deep and that acted as a sun-breaker. In Chandigarh, Le Corbusier’s buildings have sun-breakers on the outside as a separate element, but here I integrated the structure and the function of the sun-breaker into one element. I think this was a major achievement which a French architect mentioned in his book.

In terms of materials, we began thinking about steel but since steel of that much quantity was not available in the country, I had to think of concrete. I had seen Nervi’s trusses which were built in concrete, so if that could be made in concrete, why not a space frame? The idea took roots. And we were very lucky to have Er. Mahendra Raj on board and him, along with Er. Dorairaj who was the head of the pre-fabrication factory, took on the challenge of engineering our design. So this was our team. But the real challenge was that the structure had to be put up in a period of 18 months flat, and we achieved it.

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Excerpt from an interview with Er. Mahendra Raj, New Delhi, 1st November 2017;

Q – Nirmal Kulkarni – What were the challenges presented in the design of building a space-frame in RCC, especially in view of the technological innovation which it sought to be?

A – Er Mahendra Raj – I had a previous experience of having worked on large span structures in a New York engineering firm. So the scheme of construction we worked out was basically a pyramid with a double layered space-frame. In this, every individual member had to be of the same size in terms of its geometry. So all four sides had to be the same in plan and the diagonals too, and this is possible only in a certain specific angle that gave us the shape. These pyramidal units which formed the module were then placed next to each other and the whole assembly multiplied to form the full structure. 

Regarding materials, since steel members were not available I designed the structure in pre-cast concrete members and it was put to tender. However no contractor was willing to undertake the project because pre-casting required a certain level of accuracy and precision which they were not capable of. So there was no choice but to go in for a cast-in-situ construction and the lowest tenderer Puri Construction was awarded the project. We had to then rework the entire design to suit concrete pouring with shuttering and bars already in place. The joints which were so elaborately worked out for pre-cast concrete also had to undergo a change and there were places where as many as 9 members met, so you can imagine the complexity and we had a very tough time handling these at all levels.

Sifting through the distant time-zone of the construction process of the Hall of Nations through the memories of the creators was exciting, informative and humbling at the same time. The layered nuances of design stage, the frightening challenges of the constrained resources of materials and time and the heroic abandon with which the two of them engaged with the making of history for the 25th year of the Independence of India was to me nationalism embodied.

In June 2017, I was invited to present a key-note lecture at Gwalior for the Zonal NASA. I took this as an opportunity to inform students through my lecture which revolved around the Hall of Nations and concentrated on several aspects of the conceptual design phases through to the building process to the demolition and invited the students to subject the building and the event to critical analysis. 

My consistent engagement with the event goaded me to understand more deeply the issues underlying such events through the insight of other fellow professionals which led me to organize a conference which I curated and moderated at Vagamon, Kerala, through NASA and is the first of such events which will hopefully find continuity in the future.

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