O’Shell

Introduction:

“The ‘Form’ of an object is the ‘Diagram of Forces’…”
– D’Arcy Thompson

O’Shell is an attempt to design and build a structure using an interactive approach towards form-finding and analog computation, targeted at fostering an understanding of the relationship between form and force, in tension based curved surface structures, in an intuitive and playful way. The project investigated physical parameters as effective constraints in the process of design development. O’Shell is an experimental, cross-pollinated project between practice, research and academics enabling meaningful collaborations within them.

Background:

CARE Group of institutions, the client, had commissioned a structure which was to act as a hub or a node for student interaction and grow to accommodate various other student related activities within its perimeters in future. The structure was to be situated in the CARE Square, adjacent to the precinct of the student accommodation blocks. The project was met out as a consultancy to the Design cell, the research and innovation division of the CARE School of Architecture, one of the constituent schools of the group. The project was envisioned by Ar.Vijaykumar Sengottuvelan, Director of the School of Architecture and mentored by Ar.Balaji Rajasekaran, faculty at the school and Principal Architect of dMac group, young and experimental practice. The team included student architects and faculty from the school of architecture besides professionals from the dMac group.

Precedents:

The Pioneering works of legends like Antonio Gaudi, Frei Otto, Isler, Nervi, Dieste and Candela were a major source of inspiration in the conceptualization of ‘O’Shell and the confidence to adopt an interactive and instinctive approach to the project.

Techniques adopted:

O’Shell utilizes the tensile property of steel to arrive at a Non-Standard/Non-linear process with On-site active bending as a design driver without any form-work or shuttering either to hold the concrete or guide the geometry. The base framework was derived on site using site parameters as generators which was followed by weaving and bending of steel on site based on our understanding of stress line methods to inform conceptual structural design.

Principal Stress Lines, which are pairs of Orthogonal curves that indicate trajectories of internal forces and therefore, idealized paths of material continuity, naturally encode the optimal topology for any structure for a given set of boundary conditions [Tam+Mueller 2015]¹.

In general, for a ferrocement structure, a standard of 150mm spacing throughout between reinforcements is a thumb rule. In the case of O’Shell, We have managed to go up-to 750mm in the top portion of the structure by simply utilizing the understanding of force lines. The intensity of reinforcement was predominantly on the lower side (leg) of the structure.

The beauty of O’shell lies in its simplicity of execution devoid of any high-tech production systems but instead relies on the idea of human robots (hands of our students and unskilled labourers). The project was completed within 20 working days right from conceptualization of design, construction of the structure and finish.

References:
1. ACADIA 2105: Computational Ecologies: Design in the Anthropocene [Proceedings of the 35th Annual Conference of the Association for Computer Aided Design in Architecture (ACADIA) ISBN 978-0-692-53726-8] Cincinnati 19-25 October, 2015), pp. 95 109 http://papers.cumincad.org/cgi-bin/works/Show?acadia15_095