Reframing Colonial Technologies: Reinforced Brickwork in Early Twentieth-Century India
I had gone shopping in my home town of Jamshedpur in eastern India a few years ago when I first saw a reinforced brick slab. The shops are a series of single storied buildings that lined the main business and shopping street in the city. These, and most of the central parts of the city were built around the Tata Iron and Steel Company in the early decades of the twentieth century. Prior to this development, the region was a thickly forested area, home to scattered tribal communities. The factory was established in 1907 and within a decade, the site had grown into a small but bustling town.[1]
An enormous factory occupied the town center, and by the 1930s, neighborhoods with bungalows, “quarters” for lower-class workers, clubs, schools, and shops were built all around the factory. Much of the basic layout and buildings in this part of the city have remained unchanged, like the shop I was standing in. Waiting for the sales person to fetch the umbrellas we were looking for, I vaguely looked around the shop and noticed the ceiling which was missing a chunk of plaster. Exposed in the gap, were rows of brick courses, with rather corroded dark-colored bars visible along alternate joints (Figure 1). I had heard of reinforced brick slabs but had never seen one before This little peek was exciting because reinforced brick slabs seem almost magical. One wonders how the bricks seem to lie flat without anything supporting them from below!
Figure 1. Exposed section of reinforced brick slab. Photograph by Gauri Bharat.
Reinforced brickwork (RB) is a little-known technology that developed in the Indian sub-continent in the first decades of the twentieth century, around the same time as reinforced concrete (RC) began to be used around the world. Structurally, the two technologies are similar. RC combines stone, sand, or brick bats as aggregate, cement or lime as binder, and steel rods as reinforcement to produce a composite structural element that can withstand both compressive and tensile forces. In RB, on the other hand, the aggregate is replaced by bricks courses. The mortar binds the bricks and reinforcement bars to create a similar composite structural element. The slab is then covered with a rich layer of plaster, which creates an additional binding layer. So, what looks like bricks magically suspended between the reinforcement rods is in fact held together by the adhesive strength of the mortar.
The parallels in terms of structural-conceptual similarities between RB and RC suggest that they are concomitant developments within the trajectory of technological transformation in colonial India. The dominant view of colonial architectural history operates on the colonial and the Indian as mutually exclusive categories, where the former is imagined as the technologically modern, rationalizing force while the latter is the more tradition-bound indigenous counterpoint. RB, however, is best understood as a technology that emerged in the interplay of RC construction as an idea and the ecosystem of brickwork in the sub-continent. Not only does it defy categorization, it demonstrates the complex entanglements of colonial and Indian engineering in the late nineteenth and early twentieth centuries.
Anecdotal evidence of RB walls, parapets, slabs, and beams are found across the Indian subcontinent. These examples are similar in terms of the broad structural principles mentioned above, but present different details which suggest that the processes of construction varied. To illustrate this point, let me compare the Jamshedpur slabs with the more technologically sophisticated Kleine flooring system, which had been practiced in Germany since 1892 and was introduced to England in the first decade of the 1900s.[2] Over the next two decades, advertisements of Klein floors began to appear in trade magazines and engineering journals in the Indian subcontinent. According to one advertisement, the technique had been tested in India in 1912, and had been used in institutional buildings such as the Mercantile Bank Buildings in Madras, which was featured as an illustration.[3] By comparing the kind of reinforcement, placement of bricks, and specifications of stages of construction, we can deduce two very different contexts of architectural production.
The Klein floor, according to reports, followed a number of specifications (Figure 2). For a slab supported on steel girders, for instance, the first step was to place expanded steel or galvanized “netting” on the lower flange. Next, a platform was erected to temporarily support the slab while the mortar set and gained strength. The surface of the platform, the report advised, should ideally be at least one inch lower than the steel girder. Then the brick-laying would begin. The first course of bricks was placed in the span between the girders. The first brick would be supported on the flange while the subsequent bricks would be supported on the platform below. To ensure that they are at the same level, it was advised that the end of the first brick of each course be rebated. After the first course was laid, a steel strip was to be placed against the side. This was held in position by a 1-inch layer of mortar, which prevented the steel strip from settling on the platform. The next course of bricks was to be laid alongside the first one. The joints between the two were filled with mortar thus completely enclosing the steel strip. The report also suggested that every fourth pair of brick courses be laid on edge, which would serve to intermittently stiffen the slab. When the space was entirely covered with brick courses, then the platform would be eventually removed and the under surface covered in cement or lime plaster. An important goal of the design of the Klein floor was the issue of fire resistance. It was for this reason that the steel strips and girder were propped above the platform with the plaster forming a protective layer.
Figure 2. Detail of Klein flooring system. Based on report published in Builder, 3 September 1904.
The Jamshedpur slabs were constructed differently. Here, the steel girders were placed below and then the slabs were constructed over it. Also, the reinforcements used in Jamshedpur are round bars rather than steel strips. The sequence of construction is likely to have been as follows: With the steel girders in place, the workers would have constructed a platform. Starting from one end, they placed bricks such that the course extended from one girder to the other. They would then place the steel rod along the length of the course and start laying the next course. In packing mortar between the joint, the steel rod would get encased as well. They would then continue in this manner until the entire space was covered. Finally, the entire slab was covered in plaster from both above and below (Figure 3).
Figure 3. Detail of reinforced brick slab in Jamshedpur
Compared to the Kleine floor, the Jamshedpur slab has fewer detailed specifications. For instance, the end course bricks are not rebated nor are they placed on edge. Since the slab is constructed above the girder, the end conditions are simplified by using the whole brick. More importantly, the Jamshedpur slabs use rods rather than steel strips. What is interesting about this difference is that the use of flats would be structurally efficient. A steel flat bar when placed flushed against the surface of the brick course has two advantages. In terms of cross-section, a flat bar has more depth and a very narrow width. The placement of the bar ensures that the depth is optimally used to tackle the tensile forces of the slab, while the possibility of flexure along the other axis, where the bar is thin, is eliminated since it lies sandwiched between the brick courses. The rods used in the Jamshedpur slabs are comparatively inefficient. The round cross section results in a smaller depth making it more likely to bend. Also, its placement along the lower edge of the brick means that it is held in place only partially by the mortar and primarily by the final layer of plaster. In addition, when the strip is sandwiched between brick courses, it is less likely to be exposed to air even if the mortar is porous or poorly filled. This was important since exposure to air and humidity causes corrosion in the bars and leads to the eventual weakening of the slab. In comparison, the steel rods in the Jamshedpur slabs lie at the bottom of the slab and are minimally protected from exposure by the plaster layer alone. As Figure 1 shows, in many buildings today the plaster layer has fallen off revealing the corroded bars inside.
While it is tempting to dismiss the slabs in Jamshedpur as a simple case of poor or inadequate design, a different picture emerges when we triangulate structural efficiency and building performance with other factors, particularly the make-up of the construction labor force. Nearly every engineer in the late nineteenth and early twentieth-century India, be they from the ranks of the colonial public works or private building contractors, worked with a largely informal labor force which included large numbers of rural migrants who took to construction work as the first, and often only step into the wage labor. In Jamshedpur, much of labor force comprised Adivasis [Indigenous people] who had lived in and around the site where the city was being built.[4] While many of laborers may have been familiar with bricklaying, other aspects such as specific mortars or working with steel would have been new to the laborers.[5] Additionally, during these decades, while there were growing numbers of qualified engineers and technically trained supervisors, the pace of construction work across the country far outnumbered the available technical skill. Consequently, careful supervision was nearly always difficult. Such exigencies meant that the average construction project required a rationalized set of specifications, such that basic architectural, structural, and constructional goals could be achieved by the available skilled and unskilled labor force.
“If we frame the production of a building as an assemblage of materials, processes, people, and construction technologies ... categories such as colonial or local/ Indigenous ... are woefully inadequate to describe the complex overlaps in how buildings were made.”
Understood within this context, the design of the Jamshedpur slabs was clearly a response to the specific labor conditions of a very ambitious but unprecedented project in a relatively remote site. They had to be easy to assemble. In terms of instructions, the bricklayer only needed to be told that after every course (or every alternate course, depending on the size of the slab) they must place a rod along the joint and continue in this way. And once the basic slab was constructed, the lower surface, i.e. the ceiling, was to be plastered with a rich mixture. The supervisor needed to ensure that the specifications of the mortar mix, which required attention only at the time of mixing. Given the inherent strength of the materials such as brick and lime mortar, by following basic procedures, a structure of considerable strength could be achieved. In the Kleine floor, on the other hand, minor details such as the size of the rebate on each brick, the gap between the steel strip above the platform, and sequence of on-edge courses and regular courses all required extra instruction and adequate supervision to ensure that the process was correctly followed. These details would each contribute to greater efficiencies in structural performance but demanded greater precision in construction. It is not surprising then that the Klein floor as an idea and good practice circulated among the upper echelons of the colonial construction industry, i.e. as a patented technology and in professional publications which were patronized by trained engineers.
If we frame the production of a building as an assemblage of materials, processes, people, and construction technologies of the late nineteenth and early twentieth centuries appear as an incredibly diverse body of practices. This disaggregates categories such as colonial or local/ Indigenous, which are woefully inadequate to describe the complex overlaps in how buildings were made. Within the trajectory of the emergence of reinforcement concrete globally and in South Asia, reinforced brickwork breaks away as a localized tangent. And within the category of reinforced brickwork itself there are multiple threads from the precisely engineered Kleine floor to the largely improvised slabs in Jamshedpur. While the larger forces of technological change were shaping construction in the South Asian region, each instance of architectural production was situated within particular resource, labor, and knowledge networks. Decoding such details and tracing the actualization of an architectural work opens up new historiographic possibilities for colonial and South Asian architectural history.
Acknowledgements: I am grateful to my colleague Prof. Sankalpa for his inputs on the structural behavior of reinforced brickwork. I would also like to thank Mr. Swaminathan for providing access and information about the buildings of the Tinplate Company of India, Jamshedpur, and Mr. Swarup Sengupta from the Tata Steel Archives for allowing me to access their collections.
Notes
[1] Maya Dutta, “The Growth of the City: The First Phase 1909-1919,” in Jamshedpur: The Growth of the City and Its Regions (Calcutta: Asiatic Society, 1977), 9-17.
[2] “The Kleine Floor System,” in The Builder, 3 September 1904.
[3] Advertisement for “The Kleine Patent Flooring Company (India) Ltd.” in Times of India, 11 January 1924.
[4] Dutta, Jamshedpur, 11-12.
[5] For a detailed discussion on the Adivasi encounter with industrial and construction labor in Jamshedpur, see Mircea Raianu, Tata: The Global Corporation that Built Indian Capitalism (London: Harvard University Press, 2021), 68-76.
