Structural steel is adaptable to different contexts and designs
While the material is often applauded for its flexibility and versatility, the fact that it can deliver a clean, systematic construction process has also augmented its popularity.
Whether it is the trend for sleek designs or the constant drive to create the most experimental forms, structural steel is making a wide range of creative – and pragmatic – expressions possible. Most projects also no longer hide the metal structure but display it proudly, either finished in a choice of colour or by retaining its industrial simplicity. As a prefabricated element, structural steel brings in a certain level of convenience and sophistication to the construction process too – improving the time frame in which the project can be delivered. “For constructions that require large spans, flexible curves and/or heavy industrial or commercial uses, steel is highly efficient,” point out Gayathri Shetty and Namith Varma, principals, Gayathri & Namith Architects (GNA). The ability to cater to some of the most challenging projects, either in form or design brief, has made steel a go-to construction material for highly conceptual outputs. The application of this sturdy material has gone beyond engineering marvels like bridges, and has made way for futuristic, architectural feats that would have been otherwise improbable.
While the material is often applauded for its flexibility and versatility, the fact that it can deliver a clean, systematic construction process has also augmented its popularity. “A shift from the concrete-based conventional method of constructing buildings to steel structures, will halve the completion time to two years,” highlights Akshay Sekhri, marketing head, Pomegranate Design.
In an industry where time is money, this advantage cannot be stressed enough. Precision-based construction methods create less room for error or surprises – especially when executed with the right skill and knowledge. In a developing nation like ours, the many advantages of structural steel are still to be explored and practically deployed in various construction sectors. “In India, we have been hesitant to use steel for structural systems, primarily due to cost constraints. Lack of familiarity and use has led to lack of proficiency in the design of steel structural systems, limited steel fabrication capabilities and limited market support,” says Nirmal Mangal, director and country head – India, M Moser Associates.
Few projects, both within the country and outside, are breaking this cycle of ignorance and apprehension. It’s not just larger-than-life designs that are successfully resulting in steel structures. We chronicle four distinct projects, set in unique contextual environments, that use structural steel to deliver appropriate, workable designs.
MEDITATION IN STEEL
To be completed later this year, GNA’s upcoming project relies extensively on structural steel for its organic form. The Brahmrishi Ashram Meditation Centre in Tirupati is inspired by the shanka (or the conch shell). Along with the principles of Vastu Shastra, the building’s form is derived from thecharacteristics and geometry of the shanka. The conceptual design is an interpretation of the theme – ‘unshackle your thoughts and set them free’.
“Conch shells have a significant place in Indian mythology. It’s believed that, if held near the ear, the sound of the ocean humming gently resonates from within. We wanted this experience to resonate within the built space of the meditation hall, and achieved it by first identifying the geometry from its natural form and then transforming it into an integrated shell structure with progressive cut portions that would aim at heightening one’s senses during a meditation seminar – just like the experience in a place of worship,” share the architects. Creating such an uninhibited structure was possible with a steel framework that spans a wide radius, with absolutely no vertical columns within the main internal space.
The meditation centre occupies a good 1.3 acres in the 17.2-acre site, making it a fairly large structure. The shelled roof has slits at different levels for natural light to stream in and add to the serene atmosphere. “We oriented the structure in the cardinal directions, auspicious to that of a typical Hindu temple plan. The entrance vestibule to the east and the Gurusthana or Stage to the west allow the circulation pathways to move from the east to the west just like in Hindu temple architecture,” the architects add.
STEEL IN URBAN ART
Commissioned by Jindal Steel, Vibhor Sogani’s steel sculpture sits on an expansive six acres of greens between the flyovers at AIIMS crossing, Delhi. The 40ft-high creation in steel, called Sprouts, was initiated by the Delhi Government towards the beautification ofthe city. Sogani recalls sowing seeds when he was called by the government to create something that reflected the global appeal of India, announcing that we have arrived. The idea behind the installation was then to compare sprouting seeds to the nation’s growth and transformation since Independence. Steel, as a material, points to the advancements made and the promising future that lies ahead. The artist notes that the approach towards this project was different from what one tends to see in public spaces in the country. Despite the initial hurdles, Sprouts is now one of the most visible public art installations in the country.
Commissioned to M Moser Associates, a new campus in Indore for a global software company is envisioned as a sustainable integrated pedestrian-oriented environment, connecting a mix of commercial, hotel, retail and recreational space. The project is divided into four phases: headquarters building, central landscape and shared amenities phase one); commercial office and data centre (phase two); commercial office (phase three); and hotel and retail program (phase four).
with photovoltaic transparent glass façade facing south and two façades of fritted glass facing east and west with clear glazing facing north, to the lake. The interior floor plates, adding up to 15,100sq-m, revolve around an internal atrium connected by a central core and monumental stairs. Due to its challenging geometrical form, multiple structural systems were explored for the headquarters building during the concept design phase. “The studies indicated that, because of varying floor plate sizes and configurations, it would be difficult and expensive to build the project in reinforced concrete system. The studies also indicated that a steel moment frame system with composite metal deck would be the most cost-effective and constructional structural system,” architects at M Moser explain. The lateral bracing for the structure would be accomplished using reinforced concrete shear walls at the core. Additional benefit of using steel structural system would be the speed of construction and much higher level of construction tolerance and quality.
Seven years after a series of quakes affected Christchurch (New Zealand), locals have adopted a new approach to construction. A 170-page report – Reconstructing Christchurch: A Seismic Shift in Building Structural System – by co-authors Michel Bruneau from the University of Buffalo, and Greg MacRae, a professor at the University of Canterbury in Christchurch, details how the previously “concrete city” is now adopting steel construction to create stable buildings. Preventing loss of life is no longer the only objective, as the rebuilding project is carried on by locals to also prevent loss of buildings and ensure minimum structural damage. The search for cost-effective, easy-to-repair buildings, is leading local engineers and architects to create steel braced structures despite the comparatively high cost.
Similarly, a team of researchers at the University of Arizona along with few partnering universities is looking at steel collectors as a key feature that will prevent a building from collapse, even if it’s a major earthquake like the recent 7.1-magnitude quake in central Mexico and 7.3-magnitude quake that hit the Iran-Iraq border. Through the various design iterations, the research team is studying horizontal transfer of forces as opposed to vertical. The steel reinforcements fitted either in the concrete floor slabs or in beams below, will transfer earthquake forces horizontally. Computer simulations and Big Shake tests are being employed to determine the effectiveness of these engineering strategies.
STEEL IN A RURAL PROJECT
Further away in rural Africa, steel was cleverly juxtaposed with local building techniques to create a community space. Designed by Johannesburg-based Architecture For A Change (A4AC) and and executed along with the locals, the new community church in Chimphamba village, Mijinji District, Malawi, replaced the old, small dilapidated building. Along with the chiefs of the village, Youth of Malawi (a not-for-profit corporation) approached A4AC to design and manage the build of the new church/community hall.
In rural communities, these buildings also function as gathering areas to discuss important matters such as food security, community challenges, etc. Additionally, A4AC wanted to devise a building solution that could be easily built by the community builders themselves.”Through our analysis of geometric shapes in the community, it became evident that cylindrical forms resonate with safety and protection,” the architects note. From chicken coups and protection walls around small trees to maize storage structures, the widely visible circular form in the village life became a starting point for the structure’s design. “Essentially the building is a round cylinder, with three boxes that have been inserted into it. The boxes are constructed from local brick, to match the existing structures in the village. The first box serves as a foyer into the building,and the second taller box serves as a ventilation tower,” explain the architects. The central circular hall built in local burnt red bricks is supported by a lightweight steel roof with IBR sheeting (IBR sheets have become a household name in the South African building industry as side cladding or roofing material in commercial, industrial and residential buildings. With the name abbreviated from ‘inverted box rib’ owing to their square fluted profile, the sheets are made from a variety of materials). The long steel members allow for a large gathering space without any obtrusive columns getting in the way.
The circular shape of the building also helps with acoustical quality of the building. “The ventilation tower generates natural ventilation through the concept of a heat stack. The tower is heated by the sun. This leads to hot air rising towards the top of the tower. In return, this creates a suction at the bottom, drawing fresh air from the exterior,” add the architects. The climate in Chimphamba allows for the walls to remain breathable throughout the year, which, in turn, promotes enhanced natural ventilation. The light openings inside the wall were inspired by the previous church. The structure had many small holes in the decaying roof. Although this was not created intentionally, it resulted in small beams of light entering the space. This memory was replicated in the new church.
In one of their most recent projects, located in the northern part of Bengaluru, Designhaaus used structural steel to meet the client’s brief. “Our client being a man of vast experience wanted his house to reflect his philosophy that ‘simplicity is the ultimate sophistication’. Part of his initial brief was to have an organised approach devoid of all clutter that is associated with a conventional construction methodology,” share Gourav Das and Rajeev Kumar Sharma, directors, Designhaaus.
After a lot of deliberation, it was decided to build the house predominantly with structural steel. “Being a part of the petroleum and gas industry, the client had prior experience in building steel structures and was fully aware of the advantages associated with it. This nascent idea was to be extended and adapted to develop a construction methodology fulfilling the requirement of a full-fledged residence. From there on, the approach was to think beyond the obvious and explore new possibilities,” the duo add. The five-bedroom house was built on a structural system of RCC footings with ISMC (Indian Standard Medium Channel) columns, ISMB (Indian Standard Medium Beam) with steel decking sheet, finished with 50mm-thick RCC having minimal reinforcement bars. The beams are castellated allowing service lines to pass through them. The bottom surface was finished with gypsum false ceiling in the interior, while waterproof fibre cement boards were used for external application.