Salt Pans - “Flat expanses of ground covered with salt and other minerals, usually shining white under the Sun and found in deserts.” - Wikipedia. The Sambhar lake is the largest inland salt lake in India and have been gradually shrinking in size leaving behind a white terrain.
A unique landscape in itself, minimal as white and with plenitude of energy. A natural system like this provides resources which could be manipulated to produce new composite materials. This comes as a response to create new material out of sand and salt in this kind of landscape for people thriving and facing various issues while reducing the dependence on other non-linear materials and creating a circular economy and reducing the energy consumption. The structure designed takes the basis of properties of new material and ends up as a ruin value*.
The intangible issues(like water) take tangible form, inspired by traditional Indian architecture and binds the newly formed community. The architectural form is also a manifestation of age old Rajasthani architecture, incorporating features in a contemporary manner. New typologies evolve catering to the challenges presented by the site.
This thesis wouldn't have been possible without my past experiences during Summer School at TU Delft. Some of the past researchers done around salt as a building material by Emerging Objects, USA also helped me in finding a new direction.
The world map below displays the major salt pans / salt desert.
Why do this?
There have been issues that salt workers as a community face in India. The nature of their migration for jobs at salt pans changes the complete scenario. A typical solution would be to realize a permanent project using local resources to solve those issues. But what if we realize this project to also look at a bigger problem of circular economy, non permanence and sustainability, ending with a model for new infrastructure and breaking away from take, make and waste.
On a larger scale the 20th century saw the sudden boom in use of concrete, after its invention. Alternative materials were definitely found but it was hard to make way in the circular economy system because of its linear approach. The resources used to make concrete will deplete but not the urge. The natural systems around us provide materials which could be manipulated to make new composite materials and hence new structures.
Hence, this thesis tried to create a new system of self sustaining community by initiating tourism and tackling issues of salt workers.
Photo-documentation of salt pans and salt workers from various sources (swipe right to see more)
Site Analysis and Paleo-geography
Sambhar lake falls in the Arid Zone and is the largest playa(dry lake) within the Thar desert of western India (R. Sinha, B.C. Raymahashay, 2003). The lake is slowly reducing in size with time and will ultimately leave a salt flat.
Binder-jet 3D printing: This method involves using a powder supply of sand, salt and corn starch. The idea to use corn starch was inspired by Yask Kulshreshtha's (TU Delft) paper on Corncrete. Water is used as a binder, and when comes in contact with starch it binds sand and salt.This 3D printing technology has been used famously by Enrico Dini to create large scale sand structures. The final product if baked, like bricks, further increases the compressive strength of the resultant composite material. This method is comparatively easier as compared to sintering 3D printing. Also adding sand, increases the strength of the material substantially.
Sintering 3D printng: This method involves a powder supply of sand and salt only. It is binded together using high temperature called sintering process. In the above case a laser beam generates a high temperature to bind sand and salt. But in the desert, sun could be used to do the same. Inspired by Markus Kayser's 3D printing machine, which uses a fresnel lens to concentrate the Sun's heat to a point it can bind sand and salt. Both Sand and Salt have two different melting points. Sand has a higher melting point of 1600 degree celsius as compared to salt which has a melting point of 800 degree celsius. When salt starts melting it binds sand particles with itself and creates a really hard composite material.
Various material samples with different proportions of sand, salt and starch. For most of the samples their compressive strength was between 22-25 MPa but is significantly weaker in tensile strength
Since the material is weak in tensile strength, forms like arch, dome and vault are preferrable
The three structures: a bath house, a museumhaus(museum+housing) and an observatory provide the much needed upliftment. Rather than using a sand and salt brick, a gyroid brick is much efficient and is stronger. The complexity of gyroid brick can be easily handled by a 3D printer. The interstitial spaces in gyroid brick help in providing the services
Journey 1.0 -Observatory: is a bridge between heaven and earth. Dutch astronomer Kaiser said, “A good observatory must have a proper building, good instruments and competent observers.”What better way to combine Palladio’s Room Theory and astronomy, both based on Mathematics. The observatory is based on crowd science or democratic science involving the participation of both scientists and the public. The vaulted grid is used to make multiple levels like a labyrinth with an aim to explore the building. Few of these levels act as a deck for bird observatory.
Validating the use of external buffer/pavilion not only for aesthetic but also for climatic purpose
(Grid based “solar radiation exposure” performed on DIVA in Grasshopper)
Natural daylighting visualization of the observatory
Journey 2.0 -Museumhaus: is a mixed typology for a low tech museum and a housing community, developed around a stepwell. Envisioning this typology as a city without interferring with the privacy. The zone between the museum and housing acts as a buffer zone for the visitors to see the stepwell, which also acts as an exhibit for the visitors. Remembering the once forgotten stepwells, it serves as a source of water for the building complex. The capacity of the stepwell is 3000 m3 based on 75 lpcd for 30 salt workers and other areas. The dew in the desert is captured by the Tensile Structure hanging over the stepwell.
Natural daylighting visualization of the museumhaus